Publications

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2016
Osanjo GO, Oyugi JO, Kibwage I0, Mwanda WO, Ngugi EN, Otieno FC, Ndege W, Child M, Farquhar C, Penner J, Talibs Z, Kiarie JN. "Building capacity in implementation science research training at the University of Nairobi." Implementation Science. 2016;11(30). Abstractbuilding_capacity_in_implementation_science_research_training_at_the_university_of_nairobi.pdf

Background: Health care systems in sub-Saharan Africa, and globally, grapple with the problem of closing the gap
between evidence-based health interventions and actual practice in health service settings. It is essential for health
care systems, especially in low-resource settings, to increase capacity to implement evidence-based practices, by
training professionals in implementation science. With support from the Medical Education Partnership Initiative,
the University of Nairobi has developed a training program to build local capacity for implementation science.
Methods: This paper describes how the University of Nairobi leveraged resources from the Medical Education
Partnership to develop an institutional program that provides training and mentoring in implementation science,
builds relationships between researchers and implementers, and identifies local research priorities for
implementation science.
Results: The curriculum content includes core material in implemerjjation science theory, methods, and experiences.
The program adopts a team mentoring and supervision approach, in which fellows are matched with mentors at the
University of Nairobi and partnering institutions University of Washington, Seattle, and University of Maryland,
Baltimore. A survey of program participants showed a high degree satisfaction with most aspects of the program,
including the content, duration, and attachment sites. A key strength of the fellowship program is the partnership
approach, which leverages innovative use of information technology to offer diverse perspectives, and a team model
for mentorship and supervision.
Conclusions: As health care systems and training institutions seek new approaches to increase capacity in
implementation science, the University of Nairobi Implementation Science Fellowship program can be a model
for health educators and administrators who wish to develop their program and curricula.
Keywords: Implementation science, Training, Fellowship program

2015
Masika MM, Omondi GB, Natembeya DS, Mugane EM, Bosire KO, Kibwage IO. "Use of mobile learning technology among final year medical students in Kenya." Pan African Medical Journal. 2015;21(127). Abstractuse_of_mobile_learning_technology_among_final_year_medical_students_in_kenya.pdf

Introduction: Mobile phone penetration has increased exponentially over the last decade as has its application in nearly all spheres of life including health and medical education. This study aimed at assessing the use of mobile learning technology and its challenges among final year undergraduate students in the College of Health sciences, University of Nairobi.
Methods: This was a cross-sectional descriptive study conducted among final year undergraduate students at the University of Nairobi, College of Health Sciences. Self-administered, anonymous questionnaires were issued to all final year students in their lecture rooms after obtaining informed consent. Data on demographics, mobile device ownership and mobile learning technology use and its challenges was collected. Data entry and analysis was done using SPSS®. Chi-square and t-test were used for bivariate analysis.
Results: We had 292 respondents; 62% were medical students, 16% were nursing students, 13% were pharmacy students and 9% were dental surgery students. The majority were female (59%) and the average age was 24 years. Eighty eight percent (88%) of the respondents owned a smart device and nearly all of them used it for learning. 64% of the respondents used medical mobile applications. The main challenges were lack of a smart device, lack of technical know-how in accessing or using apps, sub-optimal internet access, cost of acquiring apps and limited device memory.
Conclusion: Mobile learning is increasingly popular among medical students and should be leveraged in promoting access and quality of medical education.

2014
Kibwage IO, Ndwigah SN, Amugune BK, Thoithi GN, Mwangi JW, Mugo HN. "Antibacterial and Antifungal Activity of Dombeya torrida (J.F. Gmel) and Hydnora abyssinica (A. Braun)." African Journal of Pharmacology and Therapeutics. 2014;3(2303-9841):14-18.abstract.pdf
Kibwage IO, francis njiiri, O'Malley G, Baird S, Ojoome V, Kiarie J, Davies LD. "Evolution of a Multiuniversity Monitoring and Evaluation Technical Working Group." Academic Medicine. 2014;89(8):110. Abstractevolution_of_a_multiuniversity_monitoring_and_evaluation_technical_working_group.pdf

Background: Monitoring and evaluation (M&E) of large-scale government and donor investments is essential for tracking quality improvement, documenting lessons learned, and measuring returns on investment. M&E becomes particularly salient when interventions are also large in scale and unproven, as is the case with the Medical Education Partnership Initiative (MEPI). Through the Principal Investigators' Council, MEPI institutions observed that many schools faced similar challenges in M&E and that there was a need for more collaboration across programs. In response, an M&E Technical Working Group (TWG) was established in 2012, more than two years after the onset of MEPI, to facilitate interaction across the 13 MEPI institutions. The TWG was composed of M&E leads from each school, with technical support from the MEPI Coordinating Center (George Washington University and the African Center for Global Health and Social Transformation), the University of Nairobi, and the University of Washington.

Kiarie JN, Farquhar C, Redfield R, Bosire K, R W Nduati, Mwanda W, M'imunya JM, Kibwage I. "Strengthening Health Systems by Integrating Health Care, Medical Education and Research: University of Nairobi Experience." Academic Medicine . 2014;89 (8)(August Supplement.):109-110.abstract.pdf
2013
Amugune BK, Thoiti GN, Mwangi JW, Omosa LK, Kibwage IO. "Antimicrobial Activity and Bioactive Constituents of Alectra sessiliflora (Vahl) Kuntze Methanol Extract." 3. 2013;16(1026-552X):61-68.alectra_sessiliflora.pdf
Ndwigah SN, Thoithi GN, J.W.Mwangi, B.K.Amugune, Mugo HN, Kibwage IO. "Phytosterols from Dombeya Torrida (J.G GMEL)." East Cent. Afr. J. Pharm. Sci.. 2013;16(2):1-9.abstract.pdf
K.O. ABUGA*, B.K. AMUGUNE NDWIGAHKAMAUTHOITHIOGETOOKARUNGUYOKING’ONDUMUGOSNFN. "Quality Performance of Drugs Analyzed in the Drug Analysis and Research Unit (DARU) during the Period 2006-2010." East Cent. Afr. J. Pharm. Sci. . 2013;Vol. 16(33). Abstractfull_paper.pdfWebsite

The quality of a drug product is determined by product design, manufacturing process as well as storage and distribution practices [1]. Effective quality control testing entails use of compendial or validated in-house methods [2]. The Frost and Sullivan report of 2008 revealed that 72% of the drug products in the Kenyan market were imported and majority (58.7%) of the drugs in circulation were generics [3]. The limited investment in the local pharmaceutical manufacturing industry is mainly attributable to the high cost of production which undermines competitiveness in the market [4].
Market authorization for pharmaceuticals in Kenya is granted by the national drug regulatory authority, the Pharmacy and Poisons Board after requisite evaluation of drug registration applications. The applicants are required to submit a certificate of analysis from a recognized independent laboratory operating within Kenya or the East African Community. The three Kenyan laboratories accredited to carry out pre-registration analysis for this purpose are the National Quality Control Laboratory (NQCL), Drug Analysis and Research Unit (DARU) and Mission for Essential Drugs and Supplies (MEDS) laboratory [5].
Drug quality control in DARU has been conducted since 1980 [6]. The laboratory has published periodic reports on the quality performance of drug samples analyzed therein. Previous reports have shown a continued improvement in the quality of products analyzed in DARU. In the 1980s the overall failure rate ranged from 21.6% to 31.4%, dropping to 17.6-21.1% in the 1990s and 6.1% in the years 2001-2005 [6-16]. The number of samples submitted to the DARU laboratory has gradually increased over the years due to enhanced consumption by the growing Kenyan population and drive for enhanced exports [17,18]. This paper reports on the quality performance of samples analyzed in DARU during the period 2006-2010.

2011
Dambolenaa JS;, Zuninoa MP;, Lópezb AG;, Rubinsteinc HR;, Zygadloa JA;, Mwangi JW;, Thoithi GN;, Kibwage IO;, Mwalukumbi JM;, Kariuki ST. "Innovative Food Science & Emerging Technologies.". 2011. Abstract

This work investigated the constituents and the efficacy against Fusarium verticillioides infection and fumonisin production of essential oils of Ocimum basilicum L. and Ocimum gratissimum L. from different locations in Kenya.The oil of leaves and flowering tops of O. basilicum from Sagana contained mainly linalool (95%). The flowering tops and leaves from Yatta contained mainly camphor (32.6 and 31.0%, respectively) and linalool (28.2 and 29.3, respectively). Eugenol was the main constituent in the oil of O. gratissimum leaves from both Sagana (95.5%) and Yatta (70.1%). The oil of the flowering tops had significantly less eugenol. The main component of the oil of flowering tops from Yatta was Z-β-ocimene (34.1%). Oil from both species had some antifungal activity. The oils of O. basilicum and O. gratissimum from different locations showed chemical variation, antifungal activity, free radical scavenging capacity and antimycotoxicogenic property. These properties are attributed to the phenolic compound eugenol.Industrial relevanceThis manuscript gives the chemical composition and some biological effects of essential oil of two Ocimum species in Kenya namely Ocimum basilicum L. and Ocimum gratissimum L. The work reveals that there are chemovarieties of these plants in different locations in the country. Of significance is the presence of very high amounts of linalool in one chemovariety of O. basilicum while geranial and neral are major in another. The third variety contains almost equal amounts of camphor and linalool. The first two containing high quantities of linalool, geranial and neral could be cultivated after agronomic studies to provide essential oils useful in perfumery, soap or food industry while that containing camphor and linalool may find use in medicine.Proper seed selection and good agricultural practice for O. gratissimum containing high amount of eugenol could serve as good substitute for cloves which grows best only in a few islands in East Africa. Clove oil due to its high eugenol content has many biological activities including those demonstrated in the present work, and many applications in medicine and commercial world.There is need for more research on these plants especially on cultivation and commercial exploitation of the herbs.

"P.M. NJOGUI, G.N. THOITHI, J.W. MWANGI, F.N KAMAU, I.0. KIBWAGE, S.T. KARlUKI, A. YENESEW, H.N. MUGOI AND J.M. MWALUKUMBI. Phytochemical and Antimicrobial Investigation of Girardinia diversifolia (Link) Friis (Urticaceae)." East and Central Journal of Pharmaceutical Sciences. 2011;14(3):89-94. Abstract

Root and stem extracts of Girardinia diversifolia exhibited varying degrees of activity
against Bacillus pumilus, Staphylococcus aureus, Escherichia coli, Aspergillus niger,
Candida albicans and Saccharomyces cerevisiae. Three compounds namely ~-sitosterol, 7bydroxysitosterol
and 3-bydroxystigmast-5-en-7-one, were isolated from the petroleum
ether root extract. The present study gives scientific credence to the traditional use of
Girardinia diversifolia in the management of microbial infections.

Kibwage IO, Okalebo FA, Guantai AN, Karume DW, K.Maloba, Maitai CK. "Pharmacological screening of extracts of Clematis brachiata THUNBERG (RANUNCULACEAE)." East Afric. J. Bot. 2(1): 279-289. 2011.
2010
"I.O. Kibwage.Essential oils Composition of Ocimum basilicum L. and Ocimum gratissimum L. from Kenya and their inhibitory effects on growth and fumonisin production by Fusarium verticilliodes. Innovative Food Sciences and Emerging Technologies. 11:410-414.". 2010. Abstract

This work investigated the constiw6nts and the efficacy against Fusarium verticillioides infection and fumonisin production of essential oils of Ocimum basilicum L. and Ocimum gratissimum L. from
different locations in Kenya.
The oil of leaves and flowering tops of 0. basilicum from Sagan a contained mainly Iinalool (95%). The flowering tops and leaves from Yatta contained mainly camphor (32.6 and 3 I.0%, respectively) and
linalool (28.2 and 29.3, respectively). Eugenol was the main constituent in the oil of O. gratissimum leaves from both Sagana (95.5%) and Yarta (70.1 %). The oil ofthe flowering tops had significantly less
eugenol. The main component of the oil of flowering tops from Yalta was Z-~-ocim~ne (34.1 %). Oil from both species had some antifungal activity. The oils of 0. basilicum and 0. gratissimum from
different locations showed chemical variation, antifungal activity, free radical scavenging capacity and antimycotoxicogenic property. These properties are attributed to the phenolic compound eugenol.

Amugune BK, Thoithi GN, Kibwage IO. "Liquid Chromatographic Separation of phenobarbitone, ethosuximide, phenytoin and carbamazepine on a polystyrene-divinyl benzene column." Journal of Pharmacy and Pharmacology. 2010;58 (S 105):A-39.abstract.pdf
2009
"D.S.B. Ongarora, G.N. Thoithi, F. N. Kamau, K.O. Abuga, J.W. Mwangi and I.O. Kibwage (2009). Triterpenoids from the Stem Bark if Blighia unijugata Bak (Sapindaceae)."; 2009. Abstract

Two pentacyclic triterpenoids were isolated, for the first time, from the stem bark of Bligtiia unijugat
The structures of the two compounds were elucidated 011 the basis of their spectral data as friedel

Essential Oil Bearing Plants from Kenya: Chemistry, Biological Activity and Applications. The American Chemical Society; 2009. Abstract

Essential oils are aromatic volatiles that are recovered from different plant tissues using a variety of distillation and extraction technologies. Kenya, being a country with diverse
plant genetic resources, is endowed with plant species containing essential oils, many of which have not been studied. A review of research on the chemical constituents and biological activities of Kenyan essential oil bearing plants is presented and shows that the use of these indigenous natural
resources are under-recognized and underutilized. Potential applications in cosmetic, food, agricultural and pharmaceuticalindustry, among others, are discussed.

"J.W. Mwangi, G. N. Thoithi, I.O. Kibwage on Essential oil bearing plants from Kenya: Chemistry, Biological activity and Applications. In H.Rodolfo Juliani, James E. Simon and Chi-Tang Ho (Eds). African Natural Products: New Discoveries and Challenges in C." American Chemical Society. Washington DC, USA, Chapter 27, pp 495-525.; 2009. Abstract

PIP: This research report studies several biochemical and histochemical aspects of cervical carcinoma and explores their use in follow-up of patients undergoing radiotherapy. Material came from 19 patients with invasive cervical carcinoma admitted to Kenyatta National Hospital. A control group consisted of 20 women matched for age who attended clinics at the hospital but were not suffering from any malignant disease; control tissue for histological examination was obtained from 3 women who had undergone hysterectomy for uterine fibroids. Biochemical assays for alkaline and acid phosphatases in patients with cervical carcinoma show an increase in alkaline phosphatase in carcinomatous tissue (35.7 umoles/hr/mg) as opposed to normal tissue (7.2). Acid phosphatase values were only moderately raised. Assays of the same enzymes in blood showed a less marked difference between patients and controls (ranges of 7.5-20.8 and 3-14, respectively). When examined histochemically, increased alkaline phosphatase activity was observed in connective tissue, epithelium of the glands and blood capillaries of tumor tissue. 1 section containing normal tissue bordering carcinomatous tissue demonstrated normal alkaline phosphatase activity in the normal tissue and increased activity in the tumor tissue. In summary, there is increased enzyme activity around the tumor areas, but values for serum levels show an overlap of normal and abnormal cases and are therefore not predictive. Results demonstrate a clear difference in activities of these enzymes in carcinomatous tissue and normal tissue, which may be of value in follow-up care.

2008
"A.O. MAIMA, G.N. THOITHI, S.N. NDWIGAH, F.N. KAMAUI ,O. KIBWAGE. Phytosterols from the stem bark of Combretum fragrans F. Hoffm.". 2008. Abstract

Two sterols, P-sitosterol and stigmasterol, were isolated from the stem bark of
Combretum fragrans,__The identity of these .compounds was established by-spectral
analysis.

and F. A. Okalebo, I. O. Kibwage MTGCKGAN. "Isolation of Quercetrin from Clematis brachiata Thunberg." East African Journal of Botany. 2008;1 (2) :179-181. Abstract

Quercetrin (3-0-beta-L-rbamnosyl 3', 4', 5, 7 tetra hydroxy flavone) was isolated from the
stem of Clematis brachiata Thunberg. The yield was 0.029 % w/w of dried stem powder.

"L.K. KETER, G.N. THOITHI, I.0. KIBWAGE. Development and Validation of a Liquid Chromatographic Method for the Simultaneous Analysis of Six Protease Inhibitors Using a Polymer Column.". 2008. Abstract

A liquid chromatographic method for the simultaneous determination of six human immunodeficiency virus (HI\!) protease inhibitors, indinavir, saquinavir, ritonavir, amprenavir, nelfinavir and lopinavir, VI as developed and validated. Optimal separation was achieved on a PLRP-S 100 A, 250'x 4.6 mm J.D. column maintained
at 60 °C, a mobile phase consisting of tetrahydrofuran-potassium phosphate buffer (O.lM, pH 5.0)-tetrabutylammonium hydrogen sulphate (0.11\1, pH 5.0)-water(35:30:10:25 %v/v) at a flow rate of 1.0 mllmin, with ultraviolet detection at 254 nm.
The method was found to be linear over the ranges investigated with r2 values of 0.9997-0.9915 for the six drugs. The limit of quantitation for the six drugs was 0.16 to 5.12 Ilg, while the limit of detection was 0.08 to 2.12 Ilg. The intra-day and interday precision was within the ranges of 0.39 to 1.14% and 0.55 to 1.46%,
respectively.

"OrwaJ. A.I, Keter . KI, Ouko S.P. A.,Rukunga G.M, I.O. Kibwage. Quality of some Pharmaceutical Products Manufactured in Kenya.". 2008. Abstract

Samples of pharmaceutical products were obtained from local industries and retail outlets and evaluated with respect to six quality-indicating parameters, namely content, uniformity of
weight, uniformity of diameter, friability, identity and dissolution. Out of 63 samples, compliance with quality
specifications for content, dissolution and uniformity of weight was 92%, 82% and 73% respectively. All 13 samples tested complied with the test for identification and all the antibiotic suspensions tested complied with pharmacopoeia specification for stability test. There were products with too much and with too little active content identified from among the samples that failed to comply with respective pharmacopoeia limits for chemical content. This may indicate that failure to comply with specification for active content was
probably not due to poor quality raw materials but rather to poor quality control during manufacturing process. Failure to comply with pharmacopoeia specification for dissolution and uniformity of weight may be attributed to problems in formulation procedures. Although most of the products examined showed general attributes of good quality,there are some cases where there is need for improved manufacturing
practices to achieve product quality.

2007
Kibwage IO, Mwangi JW, Thoithi GN. "Quality control of herbal medicines.". 2007. Abstract

The use of traditional and herbal medicines is gaining recognition globally. To safeguard the patient, there are legitimate demands that all medicines be safe, efficacious and of good quality. The required parameters for their quality evaluation include assessment for inorganic matter(dust),absence of adulteration microbial load, identification and profile of contents and where possible quantitation of the active compound or marker compounds. Also of importance are heavy metals, pesticides and product stability. The mixture of portions of herbs in traditional medicines complicates the quality control tests of these preparations. The content profile becomes difficult to replicate from batch to batch, while quantification of the active compound(s) in such multi-component products would require prior processing to isolate and identify the chemical compounds

2006
"B.K. Amugune, G.N. Thoithi, I.O. Kibwage. Chromatographic analysis of phenobarbitone, ethosuximide, phenytoin and carbamazepine on a polystyrene-divinyl benzene." East Cent. Afr. J.Pharm. Sci. 2006;9(1):19-25. Abstract

This research report studies several biochemical and histochemical aspects of cervical carcinoma and explores their use in follow-up of patients undergoing radiotherapy. Material came from 19 patients with invasive cervical carcinoma admitted to Kenyatta National Hospital. A control group consisted of 20 women matched for age who attended clinics at the hospital but were not suffering from any malignant disease; control tissue for histological examination was obtained from 3 women who had undergone hysterectomy for uterine fibroids. Biochemical assays for alkaline and acid phosphatases in patients with cervical carcinoma show an increase in alkaline phosphatase in carcinomatous tissue (35.7 umoles/hr/mg) as opposed to normal tissue (7.2). Acid phosphatase values were only moderately raised. Assays of the same enzymes in blood showed a less marked difference between patients and controls (ranges of 7.5-20.8 and 3-14, respectively). When examined histochemically, increased alkaline phosphatase activity was observed in connective tissue, epithelium of the glands and blood capillaries of tumor tissue. 1 section containing normal tissue bordering carcinomatous tissue demonstrated normal alkaline phosphatase activity in the normal tissue and increased activity in the tumor tissue. In summary, there is increased enzyme activity around the tumor areas, but values for serum levels show an overlap of normal and abnormal cases and are therefore not predictive. Results demonstrate a clear difference in activities of these enzymes in carcinomatous tissue and normal tissue, which may be of value in follow-up care

"B.K. AMUGUNE, G.N. THOITIDAND, I.0. KIBWAGE. Liquid chromatographic analysis of phenobarbitone, ethosuximide, phenytoin and carbamazepine on a polystyrene-divinyl benzene column.". 2006. Abstract

A liquid chromatographic method for the simultaneous assay of four anticonvulsant
drugs, phenobarbitone, ethosuximide, phenytoin and carbamazepine on a
polystyrene-divinyl benzene column is described. The method was developed by the
systematic study of different types of co-polymer materials, type and concentration
of organic modifiers, buffer pH and concentration and column temperature. A
PLRP-S 100A 8 11mcolumn maintained at 60°C and a mobile phase consisting of
acetonitrile-tert-butanol-phosphate buffer (pH 7.6, 0.2 M)-water (25:5:10:60, v/v)
were used. The flow rate was 1 ml/min with ultraviolet detection at 220 nm. The
method has been validated and used for the analysis of raw materials, finished
products and dissolution studies of the drugs.

"F.N. KAMAU, I.0. KIBWAGE,G. MURIUKI, A.N. GUANTAI, H. CHEPKWONY,J, J. HOOGMARTENS, E. ROETS, R. BUSSON. Steroidal Indoxyls: Evaluation of Pk, Values and Anti-inflammatory Activity.". 2006. Abstract

Three steroidal indoxyls, 3-oxo-16,17-seco-16-nor-l,4-androstadien-15-(7'methoxy-2-indoxyIiden)17-oic
acid, 1-(2' -indoxyJiden )-2-nor-l ,2-secocholestan-3oic
acid and 1-(5'- chloro-2-indoxyliden)-2-nor-l,2-secocholestan-3-oic acid were
synthesized and screened for anti-inflammatory activity. Their pK. values were
also determined using a solubility method. The first compound, 3-oxo-16,17seco-16-nor-l,4-androstadien-15-(7'-methoxy-2-indoxyliden)
17-oic acid, had an
EDso value of 15.3 mg/kg and a pK. of 7.09. The cholestane derivative, l-(rindoxyliden)-2-nor-l,2-secocholestan-3-oic
acid, and its chloro analogue 1-(5'chloro-2-indoxyliden)-2-nor-l,2-secocholestan-3-oic
acid had EDso values of 16.2
and 22.8 mgikg, while their pK. values were 6.56 and 7.07, respectively,
suggesting that these compounds are relatively weak acids.

"J.W. Mwangi, GN. Thoithi, I.0. Kibwage. Essential Oil of Cymhopogon winterianus Jowitt from Tanzania: Composition and Antimicrobial Activity.". 2006. Abstract

The hydro-distilled essential oil (1.6%) of fresh aerial parts of wild Cymbopogon
winterianus Jowitt was analyzed by GC-MS. Fifty compounds representing 96.5% of the oil were
identified. The main components of theoil were linalool (27.4%), citronellol (l 0.9%), geraniol (8.5%),
u-calacorene, cis-calamenene (4.3%), l3-elemene(3.9%) and longifolene (3.5%). The oil exhibited low
antimicrobial activity.

2005
"I.0. KIBW AGE, J.W. MWANGI, G.N. THOITHI. Quality Control of Herbal Medicines. .". 2005. Abstract

The use of traditional and herbal medicines is gaining recognition globally. To
safeguard the patient, there are legitimate demands that all medicines be safe,
efficacious and of good quality. The required parameters for their quality
- --evaluation-indude-assessment-for-inorganic matter-Idustj+absence of-adulterationmicrobial
load, identification and profile of contents and where possible
quantitation of the active compound or marker compounds. Also of importance are
heavy metals, pesticides and product stability. The mixture of portions of herbs in
traditional medicines complicates the quality control tests of these preparations.
The content profile becomes difficult to replicate from batch to batch, while
quantification of the active compound(s) in such multi-component products would
require prior processing to isolate and identify the chemical compounds.

"J.W. Mwangi,· G.N. Thoithi, I.0.Kibwage,M.S. Demo and M.M. Oliva,M.P.Zunino and J.A. Zygadlo. Essential Oil of Rynchosia minima DC. from Kenya: Composition and Antibacterial Properties.". 2005. Abstract

The hydrodistilled essential oil (yield, 0.1%) of semi-dried leaves of Rynchosia minima DC. was analyzed by GC and GC/MS. Twenty-four compounds representing 95.9% of the oil were identified. The major components were
found to be ~caryophyllene (30.4%), germacrene B (17.9%), camphor (7.8%), a-humulene (7.4%) and y-muurolene
(7.3%). The oil was found to exhibit antibacterial activity against Bacillus ceTUS,Staphylococcus aureus and Micrococcus luteus.

Mwangi JW, Mungai NN, Thoithi GN, Kibwage IO. "Traditional herbal medicine in national healthcare in Kenya.". 2005. Abstract

Herbal medicine is becoming increasingly popular all over the world. There are studies suggesting that herbal therapies can be effective in mating certain conditions. This has been confirmed by the classic randomized, placebo-controlled, double blind well-designed clinical trials. With reliable information on herbal medicine, it is easier to integrate these therapies with tbe mainstream medicine. It is, unlikely that patients will completely abandon use of era I medical interventions but rather in a more pragmatic manner will choose to integrate other interventions as a part of their overall armamentarium of medical interventions. Can herbal medicine be integrated with mainstream medicine in Kenya and what are the challenges? This paper discusses these and other questions in respect of herbal medicine.

2004
"J.A. Orwa, L.K. Keter, S.P.A. Ouko, I.O. Kibwage and G.M. Rukunga. Influence of Manufacturing Practices on Quality of Pharmaceutical products Manufactured in Kenya. ." E.Afr. Med. J. 2004;81(6):287-292. Abstract

Dombeya rotundifolia (Planch) belongs to the Sterculiaceae family and is wide spread in Kenya growing at an altitude of between 900 and 2250m [1]. It is used in traditional medicine in the treatment of rheumatism and diarrhea [2] syphilis [3], heart problems, hemorrhoids, dyspepsia, to regulate the menses and to hasten the onset of labor [4], to manage abdominal pains, intestinal ulceration, headache and haemorrhage, as a tonic and to cause abortion [5-6]
Some general phytochemical and pharmacological studies have been carried out on D. rotundifolia. It has notable anti-bacterial and anti infalammatory activity, and has been found to contain cardiac glycosides, saponins and tannins. It does not contain cyanogenic glycosides and alkaloids [6] the ethanol leaf extract are bacteriostatic against staphylococcus aureus. Ethanol and water extraxt and antibacterial activity against Bacillus subtilis and S. aureus [6-7]. There is no report on previous isolation of compounds from this plant

Ndwigah SN, Thoithi GN, Kibwage IO. "Phytochemical Investigation and Anthelmintic Activity of Dombeya rotundifolia, Hochst. M.Pharm.". 2004. Abstract

Dombeya rotundifolia (Hochst) is a shrub (or tree) and grows in woodland, wooded grassland and rocky mountain slopes from Ethiopia southwards to Kwazulu Natal, South Africa. It is widespread in Kenya and has many traditional uses. Roots are boiled and the soup used to treat rheumatism. Roots are pounded, soaked in water and the macerate given to children with diarrhea. Its stems and roots are used as an anthelmintic and to treat syphilis. It is also used to treat heart problems, nausea in pregnant women, headaches, haemorrhoids, dyspepsia, regulate the menses, to hasten the onset of labour and as an abortifacient. Dried entire plant is used in South Africa for treatment of diarrhea and in Tanzania for intestinal upset and to rid evil effects of witchcraft. It is also used to treat abdominal pains, intestinal ulceration, headaches, haemorrhage and as a tonic. Phytochemical studies were carried out on the methanol, chloroform, hot water and cold water extracts of Dombeya rotundifolia. All the extracts contained cardiac glycosides. The methanol, hot water and could water extracts contained saponins. None of the extracts contained alkaloids and anthraquinones. Fractionation of the chloroform extract yielded two compounds which were identified as lupeol and -sitosterol by spectroscopic methods. The extracts delayed the normal hatching of strongyle eggs while killing the eggs at high concentration. Many of the un-hatched eggs below the concentration of 5000 g/ml had developed and the larvae could be seen inside the shell but some were dead showing that the extracts retarded development of the eggs. The calculated LD50 for egg hatch assay was 2570 g/ml, 500.9 g/ml, 2709.4 g/ml and 1762.9 g/ml for the hot water, cold water, methanol and chloroform extracts, respectively. The calculated LD50 for the larvae mortality assay was 635.9 g/ml, 657.0 g/ml, 96.9 g/ml and 4195 g/ml for the hot water, cold water, methanol and chloroform extracts, respectively. The extracts killed the hatched larvae at high concentrations. The calculated LD50 for the larvae development assay was 1689.6 g/ml, 765.4 g/ml, 4909.8 g/ml and 3062 g/ml for the hot water, cold water, methanol and chloroform extracts, respectively. This showed that the extracts prevented the normal development of the larvae from Larvae1 to Larvae3 (adult stage). The most active extract in egg hatch and larvae development assay was the cold water extract, while methanol extract was the most active in larvae mortality assay. The hot water and could water extracts relaxed the isolated rabbit ileum, an effect similar to that of adrenaline, supporting the use of this plant to treat diarrhea. The methanol and chloroform extracts had no effects on the isolated rabbit ileum up to a dose of 40 mg (2 mg/ml). No extract had activity on guinea pig ileum. All the extracts had broncho-constrictive effect on guinea pig trachea. The chloroform extract had a marked negative chlorotropic and inotropic effects on the isolated rabbit heart. The methanol and the water extracts had no effects on the heart up to a dose of 20 mg. Starting with a tissue bath concentration of 0.5 mg/ml, both methanol and hot water extracts caused contraction of isolated rat uterus with activity at a concentration of 2 mg/ml being comparable to the effect of oxytocin 0.1 i.u/ml and acetylcholine 0.5 g/ml. Both chloroform and cold water extracts had no noticeable effect on the uterus upto a dose of 2 mg/ml. The oxytocin-like contractions of isolated rat uterus caused by methanol and hot water extracts supports the use of this plant decoction as an abortifacient. The extracts had high activity against Artemia salina showing they may have good pestcidal and cytotoxic activity. The LD50 of methanol, chloroform, hot water and cold water extracts were 470.7, 323.3, 30.2 and 38.5 g/ml, respectively. The LD50 of lupeol and -sitosterol was 116.2 and 95.9 g/ml, respectively. In this work, the isolation of any compound from Dombeya rotundifolia is reported for the first time. The compounds lupeol and -sitosterol were isolated from the stem bark. The present work shows there is a scientific basis for the traditional use of the plant Dombeya rotundifolia as anthelmintic, antidiarrhoeal and abortifacient.

2003
Gathumbi PK;, Thoithi GN;, Mwangi JW;, Kibwage IO;, Maingi N;, Maingi N;, Pelle R;, Wando J. "Evaluation Of Effects Of Plant Extracts On Trypanosomes."; 2003.
"F. N. Kamau, G. N. Thoithi, K. Ngugi, O. K. King'ondu and I. O. Kibwage. Quality of Amoxycillin Preparations on the Kenyan Market." East and Central African Journal of Pharmaceutical Sciences . 2003;6:57-60. Abstract

Amoxycillin products were evaluated for quality by liquid chromatography at
the Drug Analysis and Research Unit (DARU), University of Nairobi. Thirty
three of these were capsule formulations and 24 were dry suspensions. Three
capsule formulations failed the limits on content. The amoxyciIlin content in one
suspension product was below the limit, while in two other products it dropped
. below 80% on storage at 25°C for 7 days.

"F.N Kamau, I.O. Kibwage, A.N. Guantai, G. Muriuki and R. Munenge. (2003). Anti-Inflammatory and Anti-Diarrhoeal Activities of a Steroidal Indoxyl.". East Cent. Afr. J. Pharm. Sci. 8(2): 27-30; 2003. Abstract

Dombeya rotundifolia (Planch) belongs to the Sterculiaceae family and is wide spread in Kenya growing at an altitude of between 900 and 2250m [1]. It is used in traditional medicine in the treatment of rheumatism and diarrhea [2] syphilis [3], heart problems, hemorrhoids, dyspepsia, to regulate the menses and to hasten the onset of labor [4], to manage abdominal pains, intestinal ulceration, headache and haemorrhage, as a tonic and to cause abortion [5-6]
Some general phytochemical and pharmacological studies have been carried out on D. rotundifolia. It has notable anti-bacterial and anti infalammatory activity, and has been found to contain cardiac glycosides, saponins and tannins. It does not contain cyanogenic glycosides and alkaloids [6] the ethanol leaf extract are bacteriostatic against staphylococcus aureus. Ethanol and water extraxt and antibacterial activity against Bacillus subtilis and S. aureus [6-7]. There is no report on previous isolation of compounds from this plant

"K.O. Abuga, P.M. Mwagiru, G.N. Thoithi, J.M. Nguyo, J .K. Ngugi, O.K. King’ondu, H.N. Mugo and I.O. Kibwage. Quality of Antiretroviral Drugs Analyzed in the Drug Analysis and Research Unit during 2000-2003. ." East Cent. Afr. J. Pharm. Sci.. 2003;6(1):20-23. Abstract

Dombeya rotundifolia (Planch) belongs to the Sterculiaceae family and is wide spread in Kenya growing at an altitude of between 900 and 2250m [1]. It is used in traditional medicine in the treatment of rheumatism and diarrhea [2] syphilis [3], heart problems, hemorrhoids, dyspepsia, to regulate the menses and to hasten the onset of labor [4], to manage abdominal pains, intestinal ulceration, headache and haemorrhage, as a tonic and to cause abortion [5-6]
Some general phytochemical and pharmacological studies have been carried out on D. rotundifolia. It has notable anti-bacterial and anti infalammatory activity, and has been found to contain cardiac glycosides, saponins and tannins. It does not contain cyanogenic glycosides and alkaloids [6] the ethanol leaf extract are bacteriostatic against staphylococcus aureus. Ethanol and water extraxt and antibacterial activity against Bacillus subtilis and S. aureus [6-7]. There is no report on previous isolation of compounds from this plant

"M. M. OLIVA, M. S. DEMO,R. S. MALELE,C. K. MUTAYABARWA,J. W. MWANGI, G. N. THOlTHI, I. O. KIBWAGE, S. M. FAJLLACI. Essential Oil of Brachylaena huichinsii Hutch from Tanzania: Antimicrobial Activity and Composition." East and Central African Journal of Pharmaceutical Sciences . 2003;6:61-63. Abstract

The hydrodistilled essential oil of saw powder of Brachylaena hutchinsii Hutch
was analyzed by GC/MS. Twenty six compounds representing 94.7% of the oil
were identified. The main components of the oil were hydrocarbons
sesquiterpenes, caryophyllene (19.1010), f3-cubebene (15.5%), cls--calamenene
(10.5%) and o-copaene (9.0%). The oil exhibited antimicrobial activity, which
was comparable to that of gentamycin against Proteus mirabilis: It also showed
some activity against Bacillus cereus, Staphylococcus aureus, Staphylococcus
epidermidis, Micrococcus luteus and Enterococcus faecalis.

2002
"F.A. Okalebo, B.A. Rababha, A.N. Guantai, C.K. Maitai, I.O. Kibwage .W. Mwangi and W. Masengo. The Antimalarial and Antimicrobial Activity and Brine Shrimp Toxicity of Clematis Brachiata Extracts." East and Central African Journato(Phannaceutical Sciences. 2002;5:15-18. Abstract

The ill vitro antimalarial activity of the root extract in partly supports the
ethnobotanical use of the plant to manage malaria. Clematis brachiata Thunberg
(Ranunculaceae) is used in Kenya for the management of headaches, malaria and
other febrile illnesses, abdominal disorders, yaws and for skin disorders. Old stems
and leaves are chewed for the management of toothaches and sore throats. Extracts
of the plant were subjected to tests for antimalarial, antibacterial and antifungal
activity. The toxicity of the extracts was assessed using the brine shrimp lethality
bioassay. The root extract gave the highest ill vitro antimalarial activity against the
mulitidrug resistant strain, Plasmodium Jalciparum VIIS (ICso=39.24 ug/ml). The
stem and leaf extracts had insignificant antiplasmodial activity. The leaf, stem and
root extracts had no bacterial 01' fungal inhibitory effects even at very high
concentrations of 10 mg/ml. The LDso values of the stem and leaf methanol extracts
against the brine shrimp larvae was 365.60 and 66.5 Ilg/ml, respectively.

"F.N. Kamau, I.O Kibwage, G. Muriuki, A.N. Guantai, J. Hoorgmartens, E. Roets, C. Govaerts, H. Chepkwony and R. Busson. (2002). Estrogenic and Anti-Inflammatory Activities of a Steroidal Indoxyl. East Cent. Afr. J. Pharm. Sci.5(3):44-48."; 2002. Abstract

Dombeya rotundifolia (Planch) belongs to the Sterculiaceae family and is wide spread in Kenya growing at an altitude of between 900 and 2250m [1]. It is used in traditional medicine in the treatment of rheumatism and diarrhea [2] syphilis [3], heart problems, hemorrhoids, dyspepsia, to regulate the menses and to hasten the onset of labor [4], to manage abdominal pains, intestinal ulceration, headache and haemorrhage, as a tonic and to cause abortion [5-6]
Some general phytochemical and pharmacological studies have been carried out on D. rotundifolia. It has notable anti-bacterial and anti infalammatory activity, and has been found to contain cardiac glycosides, saponins and tannins. It does not contain cyanogenic glycosides and alkaloids [6] the ethanol leaf extract are bacteriostatic against staphylococcus aureus. Ethanol and water extraxt and antibacterial activity against Bacillus subtilis and S. aureus [6-7]. There is no report on previous isolation of compounds from this plant

"G. N. Thoithi , N. Maingi , D. Karume, P. K. Gathumbi , J. W. Mwangi And I.O. Kibwage. Anthelmintic and Other Pharmacological Activities of the Root Bark Extracts ofAtbizia anthelmintica Brongn." East and Central African Journal of Pharmaceutical Sciences. 2002;5 :60-66. Abstract

The anthelmintic activity of water, methanol and chloroform extracts of the root bark of
Albizia anthelmintica on strongyle-type sheep nematode eggs and larvae were examined in
vitro. In addition, pharmacological tests were carried out on the water extract to confirm
other ethnomedical uses of the plant. The water extract inhibited hatching of the nematode
eggs as well as development of larvae. It caused larval mortality at moderately high doses.
The methanol extract had no effect on the eggs and on the development of larvae, but had
high activity against survival of the larvae. The chloroform extract was the least active of
the three extracts and it had moderate effect on larval development and larval survival. In
addition, the water extract caused contraction of the smooth muscle of the guinea pig and
rabbit ileum and the rat uterus. The water extract had negative inotropic and chronotropic
effects and contractile effects on guinea pig trachea. The results support the ethnomedical
use of this plant as an anthelmintic and for prevention of hemorrhage after birth.

"G.N. Thoithi, J.M. Nguyo, K.O. Abuga, G. Mukindia, O. King'ondu,J.K Ngugi and I.O.Kibwage (2002) Drug Quality Control Work in Drug Analysis and Research Unit: Observation during 1996-2000.". 2002;5:28-32. Abstract

The Drug Analysis and Research Unit received and analyzed 26] drug samples over
a five-year period, 1996 to 2000, Samples were received from regulatory authol'ities,
local industry, non-governmental organizations, hospitals and private practitioners.
The samples analyzed constituted 59,8 (X> locally manufactured and 40,2 %
imported products. The overall rate of failure to comply with quality specifications
set out ill the respective monographs was 21.1 %, This represents 24.6 'x, and
16.2 'Yo of the 10C~11ly manufactured and imported drugs, respectively.

"G.N. Thoithli, I O. Kibwage, O. King'ondu and , Hoogmartens. Liquid Chromatographic Separation of Isoniazid, Pyrazinamide and Rifampicin on a Reversed Phase Silica Column." East and Central African Journal of Pharmaceutical Sciences. 2002;5:8-14. Abstract

A gradient liquid chromatographic method which can separate isoniazid,
pyrazinamide and rifampicin is described. A Hypersil CIS, 5 !lm, 250 mm x 4.6
mm internal diameter column was maintained at 40°C. The method was
developed by systematic evaluation of the influence of the buffer concentration,
column temperature and the mobile phase pH. The method proposed uses
isocratic elution with potassium phosphate buffer (pH 6.0; 0.05 M) for 10 min,
followed by linear gradient to potassium phosphate buffer (pH 6.0; 0.05 M)methanol
(40:60, v/v) in 5 min, isocratic elution at the same composition for a
further 15 min and then linear gradient back to potassium phosphate buffer (pH
6.0; 0.05 M) in 5 min. The flow-rate was 1 ml/min and UV detection was at 254
nm. The method was validated and it has been used for routine analysis of
tablets containing isoniazid, pyrazinamide and rifampicin. Analysis time is 35
minutes.

2001
"A. K. M. Kuria, S. De Coster, G. Muriuki, W. Maseng o, I.O. Kibwage , J. Hoogmartens, and G.M. Laekeman. Antimalarial activity of Ajuga remota Benth (Labiat ae) and Caesalpina volkensii in-vitro confirmation of e thnopharmacological use ." J. Ethnopharmacology . 2001;74:141-148. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles

"F.N. Kamau, G.N. Thoithi and I.O. Kibwage (2001). Quality of ampicillin preparations on the Kenyan market. ." East Cent Afr. J. Pharm. Sci.. 2001;4(1):25-29. Abstract

Ampicillin products, 20 capsules, 2 tablets and 23 dry suspensions were evaluated
for quality by liquid chromatography at the' Drug Analysis Research Unit
University of Nairobi. Four capsule fonnulations failed limits on content. The
Ampicillin content in 5 suspensions dropped below 80% on storage at 25°C for 7
days. The pH of most suspensions dropped on storage, but had no correlation to
decrease in chemical content.

"J.W. Mwangi, G.N. Thoithi, I.O. Kibwage , J.A. Zygadlo, M.L. Lopez, M.M. Olivia, M.S. Demo, M. Toyota and J.C. Chalchat. Constituents of the essential oil of Cymbopogon afronardus Stapf. ." East Cent. Afr. J. Pharm. Sci. 2001;4(2):43-47. Abstract

The pleasantly smelling light yellow essential oil isolated by hydrodistillation from
the leaves of Cymbopogon afronardus Stapf. (Graminea) (yield 0.4 01..) was analysed
by GC and GC-MS. Forty five compounds constituting about 95.9 'Yo of the oil were
identified. The major constituents were S-epiparadisol and intermedcol (40.9 %
together), 6S:7R bisabolone (39.5 %) and 6R:7R-bisabolone (4.4 %). The essential
oil of C afronardus was significantly different from that of C nardus (L.) Rendle.
The antimicrobial activity of the oil is also reported.

I.O.Kibwage. "K.A.M Kuria, M. De Proft, IJ. Hoogmartens and G.M. Laekeman. Cultivating the African plant Ajuga remota in Belgium and confirming it's biological activity against plasmodium falciparum. Zeitschrift fur Arzenei-& Gewurzpflanzen(Z.Arzn.Gew.Pfe.6:69-72."; 2001. Abstract

Ethnobotanical and ethnopharmacological investigations led to
identification of Ajuga remota Benth (Lamiaceae) as being frequently
used in herbal medicine treatment of malaria in Kenya. The
antimalarial activity of the plant has been confirmed by in vitro testing
against Plasmodium falciparum. In order to ensure a continuous
production of plant material we started local cultures in ieuven
(Belgium).
Micropropagation of Ajuga remota starting from seeds ona general
culture medium was not successful. Sowing the seeds in full soil in
the greenhouse resulted in a germination rate of more than 75 %.
Intensive watering was necessary to initiate germination. Within 4
months the plant could be harvested and decoctions were prepared
from the dried material. The antimalarial activity of Belgian Ajuga
remota decoctions in vitro expressed as ICso (mean ± SO) was
998 ± 168 uqirn'. This was comparable with the ICso of Kenyan
grown Ajuga remota: 974 ± 112 j.1g/ml. Greenhouse cultivation
seems to provide satisfying conditions to grow enough plants and
enabling further research into validating Kenyan herbal medicine
practice.

2000
"I.O. Kibwage and J.K. Ngugi. Sulphadoxine/Pyrimethamine tablet products on the Kenyan Market. Quality concerns . ." East Cent Afr. J.. 2000;3(1):14-19. Abstract

Sulfadoxine/Pyrimethamine tablets preparations were recently made the first line
antimalarial drug. In response to reports on falciparum malaria resistance to such
products, sulfadoxinelpyrimetbamine tablets in Kenya were evaluated for their invitro
performance using the parameters of content and dissolution test for the Active
Pharmaceutical Ingredient. One brand product had a content of both sulfadoxioe and
pyrimethamine well below allowed limits. Amongst the brands analysed only 44%
had batches that released more thanQ=60% of labelled dose in 30 minutes. Batches
of some brands bad wide variations in content with some failing the dissolution test.
Other brands released less than 60% in 60 minutes. Most brands failed the
dissolution test for pyrimethamine and 33% for both sulfadoxine and pyrimethamine.
Tbe quality of sulfadoxinelpyrimethamine products on the Kenyan market should be
a cause for concern to the drug regulatory autbority and the Malaria Control
Program.

"M.B. Jande, O. Ngassapa and I.O. Kibwage. Quality of Sulfadoxine/Pyrimethamine tablets marketed in Dar es Salaam. ." East Cent. Afr. J. Pharm. Sci.. 2000;3(1):20-34. Abstract

The quality of brands of Sulfadoxine/pvrirnethamine tablets, from nine different
manufacturers, was assessed, by determining the content of active ingredients and their
dissolution profile. All nine brands complied with the USP requirement for the content of
sulfadoxine and pyrimethamine. However, only four brands passed the dissolution test,
which according to the USP; requires that more "than 60% of each active ingredient should
be in solution in' 30 minutes. One brand failed the dissolution test, with respect to both
active ingredients, for which only 19.9°/i, and 56.9% of pyrimethamine and sulfadoxine,
respectively, were in solution, in 30 minutes. The remaining four brands, failed with
respect to pyrimethamine, for which less than 60% was in solution in 30 minutes. These
findings clearly indicate that, in addition to parasite resistance to sulfadoxine/
pyrimethamine, failure of this drug combination to cure malaria could also be due to the
sub-standard products available on the market. It is recommended that pharmaceutical
manufacturers should ensure that their products meet the required standards by
adherence to good manufacturing practice. Statutory drug control bodies should also
ensure that each product, imported or locally manufactured, meets the required
compendial standards before being permitted to be on the market.

1999
"I.O. Kibwage, J.K. Thuranira, Lily Gathu, I.M. Githiga, J.M. Nguyo, J.K. Ngugi and O. Kingo'ndu. (1999). Drug Quality Control Work in Drug Analysis and Research Unit. Observation during 1991-1995.East Cent Afr.J. Pharm.Sci. 2(2):32-36." East Cent Afr. J. Pharm. Sci. 3(1): 14-19.; 1999. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles.

"J.W. Mwangi, W. Masengo, G.N. Thoithi and I.O. Kibwage (1999) . Screening of some Kenyan Medicine Plants using the Brine Shrimp Lethality Test. ." East Cent. Afr. J. Pharm.Sci.. 1999;2(3):63-71. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles

1998
"C.K. Maitai, I.O. Kibwage, A. N. Guantai, J. N. Ombega and F.A. Ndemo (1998). A retrospective study of childhood poisoning in Kenya in 1991- 93.: East Cent. Afr.J.Pharm.Sci. 1(1):7-10." East Cent. Afr. J Pharm.Sci 2(3): 63-71; 1998. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles.

"I.O. Kibwage, C. K. Maitai and I.G. Mureithi. (1998). Alcohol content of traditional Brews and Miti ni Dawa in Kenya: East Cent. Afr. J Pharm. Sci. 1(3):54-57." East Cent. Afr. J Pharm.Sci 2(3): 63-71; 1998. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles.

"I.O. Kibwage, C. Ondari, I.G. Mureithi, J. Thuranira and J. Hoogmartens. (1998). Analysis of Co-trimoxazole products on the Kenyan market: East Cent. Afr. J Pharm.Sci. 1(2)34-38." East Cent. Afr. J Pharm.Sci 2(3): 63-71; 1998. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles.

"I.O. Kibwage, E. Ayiemba and C.O. Ondari (1998). Drug utilization and cost patterns in selected health care facilities in Kenya: East Cent. Afr.J Pharm.Sci. 1(1):11-14." East Cent. Afr. J Pharm.Sci 2(3): 63-71; 1998. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles.

"I.O. Kibwage. (1998). Quality of Pharmaceuticals in Kenya: An overview. East Cent Afr. J. Pharm. Sci. 1(3): 47- 49.". East Cent. Afr. J Pharm.Sci 2(3): 63-71; 1998. Abstract

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum. The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC(50) of the most active A. remota extract (ethanol macerate) was 55 and 57 microg/ml against FCA/20GHA and W2, respectively. For C. volkensii, it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC(50) of 404 microg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC(50) of 250 microg/ml. Further phytochemical work is being done in order to identify the active principles.

1997
"B.Hagos, I.O Kibwage, M. Mwongera, J.N. Muthotho, I.M. Githiga and G.G. Mukindia. (1997). The microbial and physical quality of recycled gloves.E.Afr.Med.J.74(4):224-226." East Cent. Afr. J Pharm.Sci 2(3): 63-71; 1997. Abstract

Plastic surgical gloves reprocessed at the Kenyatta National Hospital (KNH) were tested for microbiological and physical quality, using standard, disposable, factory sterilised surgical gloves as reference. The microbiological tests were carried out using slightly modified British Pharmacopoeia method. The tests to check on the physical integrity of the gloves were designed in our laboratories. A total of 48 pairs of each group were tested. 41.67% of the reprocessed gloves and 12.5% of the reference glove failed sterility test, whereas 47.9% of the former and 0% of the latter had physical defects. These results show significant difference in the microbiological and physical quality of the reprocessed and reference gloves. The reprocessing of plastic surgical gloves is therefore, potentially dangerous and it is strongly recommended that it is discontinued at all levels of health-care institutions.

"S. Vugigi, I.O. Kibwage , E.O. Ogaja, K.O. Mangera, H.K. Chepkwony, A.N. Mac hine and J. Kathanzu. Drug quality control work in DARU: Observations during 1991-1992." Pharm. J. of Kenya. 1997;8(2):23-25. Abstract

The Drug Analysis Research Unit
analysed 161 samples during the period
January 1991 and December 1992. Of the
samples ana lysed, 125 were locally manufactured
and 36 were imported. The
Central Medical Supplies Coordinating
Unit accounted for 100 samples while the
rest were from various hospitals and '
research institutions. 46 samples failed to
meet quality specifications. 37 of those
that failed were locally manufactured and
included two counterfeits, while 9 were
imported.

1996
"C.O. Ondari, L. Gathu, F.A. Ndemo and I.O. Kibwage (1996). Microbial contamination of oral dosage forms. NAJM, 1(2): 5-8.". East Cent. Afr. J Pharm.Sci 2(3): 63-71; 1996. Abstract

Plastic surgical gloves reprocessed at the Kenyatta National Hospital (KNH) were tested for microbiological and physical quality, using standard, disposable, factory sterilised surgical gloves as reference. The microbiological tests were carried out using slightly modified British Pharmacopoeia method. The tests to check on the physical integrity of the gloves were designed in our laboratories. A total of 48 pairs of each group were tested. 41.67% of the reprocessed gloves and 12.5% of the reference glove failed sterility test, whereas 47.9% of the former and 0% of the latter had physical defects. These results show significant difference in the microbiological and physical quality of the reprocessed and reference gloves. The reprocessing of plastic surgical gloves is therefore, potentially dangerous and it is strongly recommended that it is discontinued at all levels of health-care institutions.

"G.O. Kokwaro, T.O. Kwasa, A.A. Indalo and I.O. Kibwage (1996 ). Steady-state anti- convulsant drug levels in epileptic patients. ." E. Afr. Med. J.. 1996;73(10):679-682. Abstract

Steady state concentrations of three anticonvulsant drugs (phenobarbitone, phenytoin and
carbamazepine) were measured in plasma samples from fifteen patients (eight males and
seven females; ages: 13-49years; body weights: 44-70kg), attending the outpatient Neurology
Clinic at Kenyatta National Hospital. In addition, total protein and albumin levels were
measured in plasma from patients taking phenytoin. Total protein levels were normal
(range:6.3- 7.6g1dl) in all patients except in one patient (l0.7g1dl). Albumin levels were alsonormal
(range: 3.7-4.1g1dl)inallpatients except one (2.S4g1dl).One patient on phenobarbitone
and three patients on phenytoin had no detectable drug levels in their plasma. In the
remainder, phenobarbitone, phenytoin and carbarnazepine steady state concentrations
were 8.7-21.1mgIL (N=8), 9.3-27.3mgIL (N=6) and 10.19.7mgIL (N=S), respectively. The
unbound fraction of phenytoin in plasma (fu) was normal(approximately O.IJinsix patients,
but relatively high (0.2) in one patient. Most patients in the study complied with the
prescribed treatment and their epilepsy was controlled. Cases where drug levels were
undetectable probably arose from a lack of money to purchase all prescribed medicines
rather than deliberate non-compliance. Routine monitoring ef anticonvulsant drug levers
may improve management of epileptic patients.

"M.O. Oluka, E.S. Mi1ema, I.0. Kibwage, T.O. Kwasa , G. O. Kokwaro. A Comparative Bioavailability of four carbamazepine tablet formulations available in the kenyan market. .". 1996. Abstract

The relative bloavailabilities of three carbamazepine tablet formulations available in the
Kenyan market (Temporal", Taver" and Carbamazepine Lincoln) compared with the
innovator formulation (Tegretol") were evaluated in seven healthy African volunteers (5
males, two females; aged 22-36 years), according to a randomlsed fourway crossover study
design, following oral administration of single 200mg doses with a three week washout
period. I" vitro dissolution profiles of the tablets were also evaluated. Relative bioavailabilities
(Frel) of Temporal", TaverR and Carbamazepine Linocoln were 101.2%, 82.2% and 71.6%
respectively, compared with Tegretols, Percent drug content dissolved ill vitro after I hour
were 91.3%, 75.9% and 39.3% for Temporal's, Taverb and Carbamazepine Lincoln,
respectively. It was concluded that Temporal+ was bioequivalent to TegretolR while TaverR
and Carbamazepin Lincoln were bioinequivalent to Tegre~IR. Administration ofTaverR or
Carbamazepine Lincoln might lead to poor control of epileptic seizures.

1995
"I.O. Kibwage, A. Maina, B. Hagos and J. Hoogmartens (1995). The neutralizing capacity and sodium content of antacid brands on the Kenyan market.". E. Afr. Med. J. 72 (3): 194-197; 1995. Abstract

Seventeen brands of antacid products available on the Kenya market were investigated for their acid neutralising capacity and sodium content. Thirteen tablet products gave neutralising capacity per tablet of between 4.7 to 14.12 mMol hydrochloric acid. The neutralising capacities for the suspensions ranged between 11.97 to 34.32 mMol hydrochloric acid for 10ml suspension. The lowest neutralising capacities were obtained for products based on compound magnesium trisilicate and higher capacities for those containing magaldrate, or magnesium hydroxide or magnesium carbonate in combination with other ingredients. The fastest rate of neutralization was obtained with preparations containing carbonates and the lowest by compound magnesium trisilicate. The sodium content for the preparations was between < 0.001 mEq to 0.732 mEq sodium per minimum recommended dose. The study shows a high degree of variation in both the acid neutralising capacities and the sodium content of the different brands investigated.

"J. A. Alouch-Orwa, C.O. Ondari, I.O. Kibwage and J Hoogmartens (1995). Quality of intravenous infusion fluids manufactured in Kenya: E.Afr. Med. J. 72 (12) :800-804)." E. Afr. Med. J. 72 (3): 194-197; 1995. Abstract

The incidence and nature of microbial contamination of intravenous fluids prepared by four manufacturing establishments in Kenya was evaluated using the European Pharmacopoeia membrane filtration method for sterility testing. The percentage failures were 28.6% for source D, 18.8% for source A, 12.5% for source B and 10.5% for source C. The major contaminant was aspergillus which was isolated from samples from three sources. Candida and Staphylococcus accounted for the contamination of samples from two sources. Failure rates due to the chemical composition of the products was 66.7% for Source A, 60.0% for D, 41.7% for C and 13.3% for B. The experience of the manufacturing sites appeared to correlate with the quality of the products, with the older manufacturing establishments showing lower percentage failures.

1994
"J.W. Muritu, I.O. Kibwage, C.K. Maitai and J. Hoogmartens. Evaluation of tetracycline raw materials and finished products found on the Kenyan market. J. Pharm. Biomed. Anal. 12(12):1483-8." J Pharm Biomed Anal. 1994 Dec;12(12):1483-8.; 1994. Abstract

Contents of tetracycline, its degradation products (epitetracycline, epianhydrotetracycline, anhydrotetracycline) and a fermentation impurity (2-acetyl-2-decarboxamidotetracycline) were determined in four raw materials, 12 batches of six ointment products, four eye ointment products and nine batches of five capsule products, all sampled from the Kenyan market. The analytical method was liquid chromatography on a column packed with a poly(styrenedivinyl-benzene) material (8-microns PLRP-S 100 A). All raw materials and finished products had tetracycline contents and impurity levels within the prescribed compendial limits.

1993
"I.O. Kibwage and J.M. Nguyo (1993). In vitro evaluation of carbamazepine 200 mg tablets.". J Pharm Biomed Anal. 1994 Dec;12(12):1483-8.; 1993. Abstract

A comparative in-vitro performance of carbamazepine 200mg tablet products available on the Kenyan market was evaluated. The products which include the innovator product, Tegretol, have similar quality consonant with pharmacopoeial specifications. A batch of one of the products had a carbamazepine content of 106.6% label claim which was outside the upper limits of 105%. One product packaged in multiple-unit containers of a 1000, had an unacceptable high friability of 6.82% loss in weight. All products had good dissolution profiles and released at least 70% of the dose within 45 minutes. Drug dissolution from tablets was found to vary between batches for one product. At each sampling time, most generics had wide variations in amount of dissolved drug. The effect of such variations on tablet efficacy cannot be ascertained in the absence of bioavailability data.

"K.A. Patel and I.O. Kibwage. (1993). The community Pharmacist.". Pharm. J. of Kenya. 5(1): 10 - 11.; 1993. Abstract

A comparative in-vitro performance of carbamazepine 200mg tablet products available on the Kenyan market was evaluated. The products which include the innovator product, Tegretol, have similar quality consonant with pharmacopoeial specifications. A batch of one of the products had a carbamazepine content of 106.6% label claim which was outside the upper limits of 105%. One product packaged in multiple-unit containers of a 1000, had an unacceptable high friability of 6.82% loss in weight. All products had good dissolution profiles and released at least 70% of the dose within 45 minutes. Drug dissolution from tablets was found to vary between batches for one product. At each sampling time, most generics had wide variations in amount of dissolved drug. The effect of such variations on tablet efficacy cannot be ascertained in the absence of bioavailability data.

1992
"I.O. Kibwage (1992). An overview of quality control in the pharmaceutical industry in Kenya. 4(3): 55-57." . Pharm. J. of Kenya. 4(3): 55 ; 1992. Abstract

During a 4 year period (January 1983 to December 1986), 418 requests for drug analysis were received in the Drug Analysis and Research Unit, Department of Pharmacy, University of Nairobi. Of these requests, 212 were from Medical Supplies Coordination Unit, 190 from Government hospitals and health research institutions, 11 from the Ministry of Health Headquarters (Director of Medical Services and Chief Pharmacist) and 5 came from local pharmaceutical manufacturers. Of the samples analysed, 70.8% were from local manufacturers, 26.1% were imported and 3.1% were from undeclared sources. Failure to comply with test for quality, as set out in official compendia (B.P. Eur. ph. Ip, etc.) were observed at 45.8% for locally manufactured drugs and 31.4% for imported drug products.

"I.O. Kibwage (1992). Quality of penicillin products in the Drug Analysis and Research Unit during 1983-1990. Pharmacother.". Bull. 2(1): 16- 17.; 1992. Abstract

During a 4 year period (January 1983 to December 1986), 418 requests for drug analysis were received in the Drug Analysis and Research Unit, Department of Pharmacy, University of Nairobi. Of these requests, 212 were from Medical Supplies Coordination Unit, 190 from Government hospitals and health research institutions, 11 from the Ministry of Health Headquarters (Director of Medical Services and Chief Pharmacist) and 5 came from local pharmaceutical manufacturers. Of the samples analysed, 70.8% were from local manufacturers, 26.1% were imported and 3.1% were from undeclared sources. Failure to comply with test for quality, as set out in official compendia (B.P. Eur. ph. Ip, etc.) were observed at 45.8% for locally manufactured drugs and 31.4% for imported drug products.

"I.O. Kibwage, J.O. Ogeto, C.K. Maitai, G. Rutere, J.K. Thuranira and J. Ochieng (1992). Drug Quality Control Work in DARU. Observations during 1983-1986. E. Afr. J. 69(10): 577-580." Pharm. J. of Kenya. 5(1): 10 - 11.; 1992. Abstract

During a 4 year period (January 1983 to December 1986), 418 requests for drug analysis were received in the Drug Analysis and Research Unit, Department of Pharmacy, University of Nairobi. Of these requests, 212 were from Medical Supplies Coordination Unit, 190 from Government hospitals and health research institutions, 11 from the Ministry of Health Headquarters (Director of Medical Services and Chief Pharmacist) and 5 came from local pharmaceutical manufacturers. Of the samples analysed, 70.8% were from local manufacturers, 26.1% were imported and 3.1% were from undeclared sources. Failure to comply with test for quality, as set out in official compendia (B.P. Eur. ph. Ip, etc.) were observed at 45.8% for locally manufactured drugs and 31.4% for imported drug products.

"K.O. Mang'era, G.K. Rutere, J.K. Thuranira, R. Mithamo, A. Ochieng, S. Vugigi, E. Ogaja, J.O. Kibwage. Drug Quality Control Work at Drug Analysis Research Unit: Observations During 1987 - 1990.". 1992. Abstract

During the period 1987 to 1990, the Drug Analysis and Research Una received and analysed 130 samples, 70
samples were of local origin while 60 were imports. A total of 103 samples satisfied requirements for quality. AU
samples of methylated spirit and absorbent gauze received were of unsatisfactory quality.

1991
"I.O. Kibwage and S. Vugigi (1991). Quality of Phenoxymethylpenicillin dry suspensions.". Pharmacother. Bull. 1(1): 6 - 7.; 1991. Abstract

During a 4 year period (January 1983 to December 1986), 418 requests for drug analysis were received in the Drug Analysis and Research Unit, Department of Pharmacy, University of Nairobi. Of these requests, 212 were from Medical Supplies Coordination Unit, 190 from Government hospitals and health research institutions, 11 from the Ministry of Health Headquarters (Director of Medical Services and Chief Pharmacist) and 5 came from local pharmaceutical manufacturers. Of the samples analysed, 70.8% were from local manufacturers, 26.1% were imported and 3.1% were from undeclared sources. Failure to comply with test for quality, as set out in official compendia (B.P. Eur. ph. Ip, etc.) were observed at 45.8% for locally manufactured drugs and 31.4% for imported drug products.

"I.O. Kibwage, J. Thuranira and D. Migosi (1991). Quality performance of metronidazole tablet products on the Kenyan market.". In: E. Afr. Med. J. 68(5): 365-371. Pharmacother. Bull. 1(1): 6 - 7.; 1991. Abstract

The in vitro performance of metronidazole tablet products by different manufacturers available on the Kenyan market was evaluated. It was found that a number of generic metronidazole tablet products have quality performance equal to that of Flagyl–the innovator product. All products confirmed to pharmacopoeial specifications. Three products with percent weight loss of 1.4, 11.08 and 14.93 failed the crucial friability test, for multidose packs. Two products failed the dissolution test releasing 46.8% and 45.8% of drug in 40 minutes. Drug release from tablet was found to vary between batches for one product. Ageing appears to decrease amount of drug released from tablets but longer storage periods and more samples are required before definite conclusions are drawn.

"I.O. Kibwage. (1991). Specialization in Pharmacy Practice: An Overview. Abstract.". In: Pharm. J. of Kenya. 3(1): 107 - 108. . Pharm. J. of Kenya. 4(3): 55 ; 1991. Abstract

During a 4 year period (January 1983 to December 1986), 418 requests for drug analysis were received in the Drug Analysis and Research Unit, Department of Pharmacy, University of Nairobi. Of these requests, 212 were from Medical Supplies Coordination Unit, 190 from Government hospitals and health research institutions, 11 from the Ministry of Health Headquarters (Director of Medical Services and Chief Pharmacist) and 5 came from local pharmaceutical manufacturers. Of the samples analysed, 70.8% were from local manufacturers, 26.1% were imported and 3.1% were from undeclared sources. Failure to comply with test for quality, as set out in official compendia (B.P. Eur. ph. Ip, etc.) were observed at 45.8% for locally manufactured drugs and 31.4% for imported drug products.

1989
"C.O. Ondari, I.O. Kibwage, F.A. Ndemo and S.O. Mcligeyo (1989). Comparative bioavailability of two brands of Chlorpropamide tablets on the Kenyan market. .". In: E. Afr. Med. J. 66(10): 368-663. Pharmacother. Bull. 1(1): 6 - 7.; 1989. Abstract

The relative bioavailability of two brands of chlorpropamide, Dibonis, and Diabinese has been evaluated in four healthy male volunteers in a randomized, balanced, cross-over study. No statistically significant differences were observed in the absorption rate constant, ka, time to reach peak serum concentration, tp, maximum serum concentration, Cmax, the overall elimination rate constant, kel, and the area under the curve, AUC, at 95% confidence level.

"I.O. Kibwage and J.N. Ombega (1989). Pharmacy practice: Past present and future.". In: Pharm J. of Kenya. 2(3): 75 & 89. Pharmacother. Bull. 1(1): 6 - 7.; 1989. Abstract

The relative bioavailability of two brands of chlorpropamide, Dibonis, and Diabinese has been evaluated in four healthy male volunteers in a randomized, balanced, cross-over study. No statistically significant differences were observed in the absorption rate constant, ka, time to reach peak serum concentration, tp, maximum serum concentration, Cmax, the overall elimination rate constant, kel, and the area under the curve, AUC, at 95% confidence level.

"I.O. Kibwage, M. Michiels, R. Hendiricks,Cachet, A. Verbruggen, J. Hoogmartens and H. Vanderhaeghe.Tissue distribution and excretion of radioactivity in the Wistar rat after administration of (N-methyl-14c) erythromycin A.Eur.J.Drug Metab Pharm 14(1):7-14." Pharmacother. Bull. 1(1): 6 - 7.; 1989. Abstract

Tissue distribution and excretion of radioactively labelled compounds was studied in the Wistar rat after i.v. administration of [N-methyl-14C]-erythromycin A. Whole-body autoradiography and liquid scintillation counting was used to investigate the tissue localization of radioactivity in pregnant and non-pregnant rats. Tissue levels were maximal within 20 min, except for lachrymal glands, thymus and brain. Large amounts of radioactively labelled compounds, partly originating from active secretion, were present in the small intestine and caecum. Marked concentration of radioactively labelled compounds was also observed in the liver, spleen, lachrymal and salivary glands, lymph nodes, mammary glands, skin, bone marrow, and, to a lesser extent, in the lung, kidney and skeletal muscle. During six hours of experimental follow-up, plasma levels remained lower than corresponding tissue levels. At 1 h the radioactivity in fetuses was about three times lower than that in maternal blood. Within 48 h, more than 90% of the administered radioactivity was excreted. The amounts of radioactivity recovered in urine, faeces and expired air were about 19%, 48% and 24% respectively. After 48 h, 8% of the administered radioactivity was found in the carcass.

"J.N. Ombega and I.O. Kibwage (1989). Curriculum Development: What considerations. Abstract.". In: Pharm. J. of Kenya. 2(3): 87 - 89. Pharmacother. Bull. 1(1): 6 - 7.; 1989. Abstract

The relative bioavailability of two brands of chlorpropamide, Dibonis, and Diabinese has been evaluated in four healthy male volunteers in a randomized, balanced, cross-over study. No statistically significant differences were observed in the absorption rate constant, ka, time to reach peak serum concentration, tp, maximum serum concentration, Cmax, the overall elimination rate constant, kel, and the area under the curve, AUC, at 95% confidence level.

1988
"I.O. Kibwage , E. Roets, A. Verbruggen, J. Hoogmartens and H. Va nderhaeghe. Thin layer chromatographic study of the metabolites of erythromycins in the wistar rat. J.Chromatogr (Biochemical applications).". 1988;(434):177-186. Abstract

The metabolites of erythromycin A, anhydroerythromycin A, Nedemethylervthromycin A and
erythromycin B in the Wister rat were studied by thin-layer chromatography. In some experiments
germ-free rats, rats with a cannulated bile duct and a gastrectomized rat were used. The erythromycins
examined were shown to undergo two principal changes, N-demethylation and acid-catalysed
degradation. It was demonstrated that the stomach and the liver are not the solesites of acid degradation
and demethylation oferythromycins, respectively. Erythromycin A gives three principal metabolites,
anhydroerythromycin A,anhydro-N-demethylerythromycin Aand N-demethylerythromycin
A,and erythromycin A enol ether and N-demethylerythromycin A enol ether are present to a minor
extent. 5-0-Desosaminyleryt.ironolide A was also identified, suggesting the presence of an erythromycin
glycosidase.

"I.O. Kibwage and C.O. Ondari (1988). Quality control of Aspirin tablet products on the Kenyan market." Pharm. J. of Kenya. 1988;1(3):80. Abstract

A comparatlve evaluation of •••
alpirln tablets products on the Kenyan
rmlrket found that three of the products
failed to meet compendlal requlntfTMtnts.
A fourth had poor friability. The only
Imported product among' those
evaluated failed weight unlformlry test.
One local product failed In diameter
requirement while another had an
aspirin content of 111'10 of the lable
claim.

"O. Kibwage , C.O. Ondari and F.A. Ndemo (1988). In equivalence of some pharmaceuticals on the Kenyan market. ." Pharm. J. of Kenya.. 1988;1(2):43. Abstract

An In vitro assessmentof two types of
products showed major deficiencies In
formulation' and manufacture. Some
antlasthmatlc syrups containing
ephedrine, phenobarbitone and
theophylline had evidence of
precipitation of phenobarbitone and
theophylline. Other Investigations
shoWedthat products aremarketedwith
declared active moiety different from
that used in the manufacture. Properly
conducted product development and
adequately trained quality assurance
personnel would alleviate such
problems

1987
"I.O. Kibwage , G. Janssen, R. Busson, L. Verbist, H. Vanderhaegh e (1987) . Identification of Novel erythromycin derivatives in mother liquor concentrates of Streptomyces erythreus. ." J. Antibiot. 1987;40:1-6. Abstract

The identification of five novel compounds, pseudo-erythromycin A-6,9-hemiketal, 8,9anhydro-pseudo-erythromycin
A-6,9-hemiketal, 8,9-anhydro-pseudo-N-demethylerythromycin
A-6,9-hemiketal, 5-0-,B-D-desosaminylerythronolide A and 15-nor-erythromycin C, in mother
liquor concentrates of Streptomyces erythraeus is described. The pseudo-erythromycin
derivatives are characterized by a 12-membered macrocyclic ring as a result of CW->Cll
trans-Iactonization. The five compounds have very little antimicrobial activity.
In a study" dealing with the isolation and the identification of compounds present in the mother
liquor concentrates from commercial crystallization of erythromycin, a number of compounds were
obtained. Some of these compounds were identified as erythromycins A, B, C and D, erythromycin
A enol ether, anhydroerythromycin A, anhydroerythrornycin C and anhydro-N-demethylerythromycin
A. Five other compounds denoted Ml to M5 were not identified. The determination of the structure
of the latter group of compounds is the subject of this paper.

"I.O. Kibwage , R. Busson, G. Janssen, J. Hoogmartens, H. Vanderh aeghe and J. Brake. Translactonization in erythromycins. ." J. Org. Chem.. 1987;52(6):990-996. Abstract

When erythromycin A is heated in diethylamine-acetic acid, an erythromycin hemiketal is obtained, which
can be further transformed into a new enol ether and spiroketal. The new enol ether is also obtained in equilibrium
with the normal one on heating erythromycin A or B in pyridine-acetic acid. The novel compounds, which will
be called pseudoerythromycin derivatives, are characterized by a translactonization between the Cwhydroxyl
and the lactone group. Their structure was proved by mass and IHand 13CNMR spectrometry, by acetylation
experiments, and by degradation with lead tetraacetate.

"T. Cachet, I.O. Kibwage , E. Roets, J. Hoogmartens and H. Vanderhaeghe (1987). Optimisation of the separation of Erythromycin and related substances by high liquid chromatography . J. Chromatogr. 409 : 91 – 100. .". 1987. Abstract

An improved high-performance liquid chromatographic method for analysis
of erythromycin is described. The separation can be performed under mild conditions
of pH (6.5) and temperature (3SOC) on C, and CJ a silica-based reversed-phase materials
of different origins. The mobile phase, with a flow-rate of 1.5 ml/rnin, contained
various amounts of acetonitrile (25-40%, v/v), 5% (vi v) 0.2 M ammonium
phosphate buffer pH 6.5, 20% (v/v) 0.2 M tetramethylammonium phosphate and
water. UV detection at 215 nm allows quantitation of erythromycins A, Band C,
N-demethylerythromycin A, erythromycin A enol ether and anhydroerythromycin
A. The column history plays a major role, older columns often giving better separations

1985
I.O. Kibwage (1985). A study on new metabolites of streptomyces erythreus and on the metabolism of erythromycin. Doctor of Pharmaceutical Sciences Thesis, Katholieke Universiteit Leuven, Belgium..; 1985. Abstract

The identification of five novel compounds, pseudo-erythromycin A-6,9-hemiketal, 8,9-anhydro-pseudo-erythromycin A-6,9-hemiketal, 8,9-anhydro-pseudo-N-demethylerythromycin A-6,9-hemiketal, 5-O-beta-D-desosaminylerythronolide A and 15-nor-erythromycin C, in mother liquor concentrates of Streptomyces erythraeus is described. The pseudo-erythromycin derivatives are characterized by a 12-membered macrocyclic ring as a result of C13––C11 trans-lactonization. The five compounds have very little antimicrobial activity.

"I.O. Kibwage , G. Janssen, E. Roets, J. Hoogmartens and H. Vand erhaeghe. Isolation of erythromycins and related substances f rom fermentation residues of Streptomyces erythreus by high performance liquid chromatography on silica gel. ." J. Chromatogr. . 1985;346:309-319. Abstract

Preparative high-performance liquid chromatography on silica gel allows the
isolation of erythromycins and related substances from mother-liquor concentrates.
Three mobile phases were used consecutively: A. ethyl acetate-methanol-25% ammonia
(100:8: I, v v); B. diethyl ether-methanol-25% ammonia (100:7: I. vjv) and C.
dichloromethane-methanol-25% ammonia (100:5:0.5. v v), The separation and purification
was confirmed by thin-layer chromatography. Thirteen pure substances were
isolated among which are erythromycins A. S, C and D. 8,9-anhydroerythromycin
A-6.9-hemiketal. erythromycins A and C-6.9;6.12-spiroketals and N-demethylerythromycin
A-6.9:9,12-spiroketaL

"I.O. Kibwage , J. Hoogmartens, E. Roets, H. Vanderhaeghe, L. Ver bist, M. Dubost, C. Pascal, P. Petitjean and G. Levol. Antibacterial activity of erythromycins A,B,C and D and some of their derivatives. J. Antimicrob. Agents Chemother. 28(5) : 630 - 633.". 1985. Abstract

The MICs of erythromycins A, B, C, and D and some of their derivatives wcrc determined against 21
gram-positive and 15 gram-negative microorganisms. Antibacterial activity was conlined 10 gram-positive and
very few gram-ncgative bacteria. Erythromycin It was somewhat less active than crythromycin A, and
erythromycin C and D showed about half Ihal activity or even less. Most olher derivatives had negligible
activity. Determination of potency by diffusion and turbidimetric assays were in line with MICs. The
cxuminauon of Ihe results of these assays, however, revealed that Ihere are differences between thc data of
dittcrent laboratories, depending on the microorganisms and conditions used,

Kibwage IO, Roets E, Hoogmartens J, Vanderhaeghe H. "Separation of erythromycin and related substances by high-performance liquid chromatography on poly (styrene-divinylbenzene) packing materials.". 1985. Abstract

A comparative evaluation of three brands of polyrstyrene-divinylbenzene) co¬polymers, Hamilton PRP-I (10 ,um), Rogel (8 ,um) and TSK-Gel (10 Jim), as column packing materials for high-performance liquid chromatographic separation of eryth¬romycins is presented. Erythromycins A, Band C, anhydroerythrornycin A, eryth¬rornycin A enol ether, Nvdcmcthylerythromycin A, anhydro Nvdemethylerythro¬myci n A and Nvdemethylerythromycin A enol ether were chromatographed. The effects of column temperature, concentration of organic modifier in the mobile phase, concentration of phosphate buffer, the addition of quaternary ammonium salts and pH are described. The best separations were obtained on TSK-Gel with the mobile phase acetonunle-methanot-uz M tetramethylammonium hydroxide pH 8.0-0.2 M phosphate buffer pH 8.0-water (30:15:25:5:25). PRP-l and Rogel gave equally good separations but with higher retention volumes .

1984
Kibwage IO, Janssen G, Busson R, Roets E, Hoogmartens J, Vanderhaeghe H. "Preparative high performance liquid chomatography on straight silica gel of fermentatio liquor of Streptomyces erythreus.". 1984.
1983
"I.O. Kibwage, E. Roets and J. Hoogmartens. Thin layer chromatography of erythromycins and other macrolides. J. Chromatogr. 256:164-171.". 1983. Abstract

The literature on the thin-layer chromatography (TLC) of macrolides has recently
been reviewed'>'. An improved separation of the components of erythromycin
has been reported by Vanderhaeghe and Kerremans '. The use of high-performance
thin-layer chromatography in the analysis of some macrolides has been the subject of
a recent publication".
The best TLC system known, described for the separation of erythromycins,
uses plates coated with silanized silica gel and methanol-water-15 % ammonium
acetate buffer pH 7.0 (50:20:10) as the mobile phase:'. This system (R-VI in Table I)
allows very good separation of erythromycin A (EA), B (EB) and C (EC), but erythromycin
D (ED) is not separated from EA. Small amounts of acid degradation
products of erythromycin such as anhydroerythromycin A (AEA) and erythromycin
A enol ether (EAEN) were found by high-performance liquid chromatography
(HPLC) of commercial samples'': TLC with system R-VI did not separate AEA
from EB. Preparative chromatography of the mother liquors of the erythromycin
purification indicated the presence of des-N-methylerythromycin A (dMeEA). As this
compound was not separated from erythromycin A with TLC system R-VI, other
mobile phases were examined. In the present study a system using silica gel as the
coating material and diisopropyJ ether-methanol-25 % ammonia (75:35:2) as the
mobile phase was found to separate EA, EB, Ee, ED, EAEN, AEA and dMeEA. The
results obtained with several other mobile phases are also discussed, together with
their application in the identification and purity control of other macrolides

1982
"I.O. Kibwage (1982). Isolation and Identification of metabolites, and their degradation products from a strain of Streptomyces erythreus. Master of Pharmaceutical Sciences Thesis, Katholieke Universiteit Leuven, Belgium.". Antimicrob Agents Chemother. 1985 Nov;28(5):630-3; 1982. Abstract

The identification of five novel compounds, pseudo-erythromycin A-6,9-hemiketal, 8,9-anhydro-pseudo-erythromycin A-6,9-hemiketal, 8,9-anhydro-pseudo-N-demethylerythromycin A-6,9-hemiketal, 5-O-beta-D-desosaminylerythronolide A and 15-nor-erythromycin C, in mother liquor concentrates of Streptomyces erythraeus is described. The pseudo-erythromycin derivatives are characterized by a 12-membered macrocyclic ring as a result of C13––C11 trans-lactonization. The five compounds have very little antimicrobial activity.

1980

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