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Combined Antibacterial and Antifungal Activities of Eucalyptus citriodora and Syzygium aromaticum Essential Oils
No full textBackground: The increasing proportion of skin infections encountered in general practice represents a substantial level of morbidity. The emergence of multi-drug resistant strains is a formidable threat to the fight against skin diseases and hence alternative forms of treatment are essential. Syzygium aromaticum and Eucalyptus citriodora oils as single entities have demonstrated potency against some of the concerned micro-organisms and any synergistic activity between the two oils could minimise development of resistance by the microorganisms to the two oils. Objective: The aim of this study was to evaluate for synergism between Eucalyptus citriodora and Syzygium aromaticum essential oils against selected pathogenic microorganisms of the skin. Materials and methods: Eucalyptus citriodora (eucalyptus oil) and Syzygium aromaticum (clove oil) essential oils were used in this study. In-vitro antimicrobial activities of Sysygium aromaticum and Eucalyptus citriodora oils, alone and in combination were tested against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa, E. coli ATCC 25922, MRSA, Candida albicans, Trichophyton mentagrophytes, Microsporum gypseum and Cryptococcus neoformans. Results: The combination of the two oils exhibited synergistic activity against Staphylococcus aureus (FICI: 0.240), E. coli (FICI: 0.54), MRSA (FICI: 0.48), and Microsporum gypseum (FICI: 0.36) while the combination exhibited additive activity against Candida albicans (FICI: 2.04). Conclusion: The combination of clove and eucalyptus oils possesses synergistic activity against most of the test pathogens and therefore may be combined for enhanced antimicrobial activity against a wide range of skin disease-causing microorganisms. Keywords: antifungal, antibacterial, synergism, Eucalyptus citriodora, Syzygium aromaticum, essential oil
In vivo antifertility activity and phytochemical screening of selected Kenyan medicinal plants
No full textBackground: Medicinal plants are reported in folklore to play a role as fertility control agents. Very few studies have been carried out to confirm the safety and efficacy of medicinal plants used as anti-fertility agents. Objective: To establish anti-fertility activity, safety, effect on genital organs and estrous cycle, and phytochemical profile of total extracts from Terminalia brownii, Ximenia americana, Bridelia micrantha, Rhoicissus revoilii, and Ocimum masaiense. Methodology: Extracts of water and organic solvents were administered to female mice at a dose of 800 mg/kg orally for antifertility tests and at a dose of 0 to 5000mg/kg orally for acute toxicity test. Phytochemical screening was done using thin layer chromatography. Results: The leaf water extracts of the Bridelia micrantha, Ximenia americana showed a reversible anti-fertility effect while ethyl acetate extracts of the stem bark of Terminalia brownii had an irreversible anti-fertility effect. The bioactive extracts had an effect on the estrus cycle and had different phytochemical compounds with no signs of toxicity. Discussion: The plant extracts tested exhibited antifertility activity, suggesting potential alternative to the current birth control methods. Compounds such as steroids, terpenoids, alkaloids, saponins and flavonoids present in the bioactive extracts may have contributed to the anti-fertility activity. Key words: Anti-fertility; Bridelia micrantha; Terminalia brownii; Ximenia American
Manpower Development In The 21st Century: The Role Of Distance Education
No full textGenerally, education is considered one of the biggest instruments for development; a means for realizing social, cultural, economic and political needs and aspirations. However, in many African educational institutions there is an enormous challenge in training a cadre of highly qualified professionals to fuel such development. There are inadequate educational resources, due to loss of the best talented faculty to the developed world. In addition, contemporary educational thought holds that one of thepivotal causes of inadequate school performance is the inability of schools to adequately staff classrooms with qualified teachers, especially in fields such as mathematics and science (Gordon and Thomas, 2007, p.43). To address the issue of teacher shortages in Kenya, some single mode universities converted themselves into dual-mode. Among them is the University of Nairobi. Apparently, the belief among academics is thatconventional education is real education. This makes distance education to act as complementary and worse of all supplementary. This paper sets out to compare whether there is a significant difference in TP performance between B.Ed (Science) Distance and on-campus students. A sample of 181 students: face-to-face n=131 vs. distance learning n= 50 students was used. The instrument of data collection was an observation guide. Though students taking courses by on-campus mode outperformedtheir counterparts in the distance mode of learning, this paper will conclude that distance learning should be treated as the emerging standard of quality in higher education and can effectively perform a complementary function, which should alleviate teacher shortage in Kenya. This study has demonstrated that science can be successfully taught by distance mode even given the current technological investment levels. This is important for policy because it leverages on what is available and the change that can bring especially in the area of manpower development, access and equity. The researchers argue that raising the technological level is not difficult since this can be done through collaboration with specialized bodies such as the African Virtual University (AVU) that is spearheading the infusion of ICTs and e-learning into the educational arenaKey words: Distance education, face-to-face learning, teaching practic
Top Management Team, Diversity Management Strategies and Performance Of Commercial Banks In Kenya
Get PDFDiversity is an increasingly important factor in organizational life as organizations worldwide become more diverse in terms of gender, race, ethnicity, age and other characteristics. There have been different findings as to whether Top Management Team (TMT) diversity affects the performance of organizations. Some researchers argue that diverse TMT have the potential to result in strategic decision making, greater creativity, more innovation and the ability to reach more and different types of customers. Others however arge that demographic variation signals variations in underlying and invisible cognitive processes which can be a source of strive. Effective human resources strategies recognize that organizations can benefit from Top Management Team diversity by creating an environment that attracts people from diverse background and recruits the best staff regardless of ethnicity, gender or age. As a result, this study sought to find out the effect of Diversity Management Strategies on the relationship between TMT diversity and the performance of commercial banks in Kenya. All the Heads of Human Resources in the 43 commercial banks operating as at December 2010 were targeted and 33 responded. The main tool of data collection was the questionnaire while the data was analyzed using regression analyses. The study found that diversity management strategies had a significant effect on the relationship between TMT diversity and organization performance. Diversity Management strategies create and maintain an environment that naturally allows all individuals to reach their full potential in pursuit of organizational objectives for competitive advantage. Diversity management strategies will ensure that the interests of the minorities in commercial banks in Kenya are well taken care ofKey Words: Top Management Team (TMT) Diversity, Diversity Management Strategies, Organization Performanc
Isolation, characterization and antimicrobial analysis of Ethyl gallate and Pyrogallol from Acalypha wilkesiana var. lace-acalypha (Muell & Arg.)
No full textBackground: Acalypha wilkesiana var. lace-acalypha (Muell & Arg.) is a cultivated ornamental plant used in folkloric medicine for the treatment of fever, bacterial, skin fungal infections, wounds, tumors, inflammations and gastro-intestinal troubles. To date, there are no reports of any isolated compounds from this species/variety which could serve as chemotaxonomic markers. Hence, the need for this study. Objectives: The leaves of the plant were to be collected and extracted cold in 50 % ethanol to obtain the crude extract. The aqueous solution of the crude extract was to be partitioned with butanol. The obtained butanol fraction was to be separated on a silca-gel column to obtain isolates which were to be screened for antimicrobial activities. Methodology: Isolates expected to be obtained from the silica-gel column chromatography of the butanol fraction were to be analyzed for antimicrobial activities using the hole-in agar diffussion method. The compounds were to be screened for both antibacterial and antifungal activities using the microbes namely, B. subtilis, S. aureus, E. coli, Ps. aeriginosa and S. typhi. and C. albicans. Results and Discussion: Two polyphenolic compounds, designated as compounds 1 [m.pt (148-150 0C); Rf (0.67); [n]20D (1.4118 )] and 2 [(m.pt 130-132 0C); Rf (0.46); [n]20D (1.4079)] were isolated. The structures of 1 and 2 have been established to be ethyl 3, 4, 5-trihydroxybenzoate (ethyl gallate) and 1, 2, 3-benzenetriol (pyrogallol or fouramine brown) respectively using the 1H NMR, 13C NMR, MS and IR spectral techniques. Both polyphenols were strongly bacteriostatic against B. subtilis, S. aureus, E. coli, Ps. aeriginosa and S. typhi. Furthermore, 2 was more suppressive of the bacterial strains than 1. However, neither gave any anticandidal activity. The crude extract and butanol fraction demonstrated comparatively weaker antimicrobial activities than the two isolated compounds. Conclusion: The two polyphenols would serve as chemotaxonomic markers for this species/variety and the genus, Acalypha in general. Also the results of the antimicrobial screening have lent scientific credence to the traditional uses of the plant. Key words: Polyphenols; ethyl gallate; pyrogallol; bacteriostatic; A. wilkesiana var. lace-acalyph
Comparison of variously prepared Momordica charantia aqueous leaf extracts on the isolated mammalian jejunum
No full textBackground: Momodica charantia is a highly valued herb in tropical and subtropical region for its numerous medicinal advantages. These include: management of bacterial infections and diabetes. In spite of wide consumption of its aqueous leaf extract stored and prepared in various conditions, their pharmacological activities on the jejuna are yet to be documented. The potential of differently prepared extracts having varied effects on the jejuna focused the researcher’s attention. Objectives: To demonstrate the effects of Momordica charantia aqueous leaf extract prepared and stored under various conditions on the isolated mammalian jejuna. Methodology: Six healthy rabbits were included. Each rabbit was sacrificed and the jejuna mounted on the Langerndorff apparatus. Baseline rate and force of contraction were recorded, after which each of the various aqueous leaf extract was administered in increasing doses and changes in rate and force of contraction noted. Paired T-test and repeated measures ANOVA were used to test for statistical significance. P values less than 0.05 indicated statistical significance. Results: There was a significant (P<0.05) dose depended increase in jejuna rate and force of contraction with the administration of the various extract preparations. The increase noted was highest and lowest after the administration of fresh boiled extract and fresh aqueous leaf extract respectively. Discussion: Momordica charantia aqueous leaf extract stored under different conditions have a significant (P<0.05) dose related effect on jejuna rate and force of contraction. The increase is dose depended and irreversible. Keywords: Momordica charantia, various extract, jejuna
Combined Antibacterial and Antifungal Activities of Eucalyptus citriodora and Syzygium aromaticum Essential Oils - Supporting Information
No full textBackground: The increasing proportion of skin infections encountered in general practice represents a substantial level of morbidity. The emergence of multi-drug resistant strains is a formidable threat to the fight against skin diseases and hence alternative forms of treatment are essential. Syzygium aromaticum and Eucalyptus citriodora oils as single entities have demonstrated potency against some of the concerned micro-organisms and any synergistic activity between the two oils could minimise development of resistance by the microorganisms to the two oils. Objective: The aim of this study was to evaluate for synergism between Eucalyptus citriodora and Syzygium aromaticum essential oils against selected pathogenic microorganisms of the skin. Materials and methods: Eucalyptus citriodora (eucalyptus oil) and Syzygium aromaticum (clove oil) essential oils were used in this study. In-vitro antimicrobial activities of Sysygium aromaticum and Eucalyptus citriodora oils, alone and in combination were tested against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa, E. coli ATCC 25922, MRSA, Candida albicans, Trichophyton mentagrophytes, Microsporum gypseum and Cryptococcus neoformans. Results: The combination of the two oils exhibited synergistic activity against Staphylococcus aureus (FICI: 0.240), E. coli (FICI: 0.54), MRSA (FICI: 0.48), and Microsporum gypseum (FICI: 0.36) while the combination exhibited additive activity against Candida albicans (FICI: 2.04). Conclusion: The combination of clove and eucalyptus oils possesses synergistic activity against most of the test pathogens and therefore may be combined for enhanced antimicrobial activity against a wide range of skin disease-causing microorganisms. Keywords: antifungal, antibacterial, synergism, Eucalyptus citriodora, Syzygium aromaticum, essential oil
APPLICATION OF THE EMS-WRF MODEL IN DEKADAL RAINFALL PREDICTION OVER THE GHA REGION
Get PDFThe IGAD Climate Prediction and Applications Centre exists to monitor and predict the patterns of rainfall over the greater Horn of Africa region, and provide early-warning products and information, particularly concerning recurrent drought episodes and localized flooding. Forecasting on dekadal (ten-day) timescales is critical because it is the bridge that links short term scales, called the NWP range, and seasonal scales. This study seeks to assess the validity of downscaled GCM rainfall outputs by the Environmental Modelling System’s Weather Research and Forecasting (EMS-WRF) model in 2011. The results reveal that the EMS-WRF model, by and large, performs well over the region, but the excellence of the forecast products varies temporally and spatially. Nonetheless, the model exaggerates rainfall amounts over certain areas, particularly that forced by mesoscale systems. Moreover, the model generally underestimates the rainfall amounts arising from unexpected storms, and displaces the areas of the highest rainfall intensity in several respects. The EMS-WRF model is useful for predicting the distribution of dekadal rainfall over the GHA, but may perform better through improving the ocean-atmosphere interactions and feedback processes and employing multi-model ensemble forecasting techniques. The model should be used cautiously in tandem with other forecasting techniques.Key words: EMS-WRF model, rainfall, prediction, forecasting, dekad, dekadal, ICPA
PUBLIC PROCUREMENT LEGAL FRAMEWORK IMPLEMENTATION CHALLENGES AND ORGANIZATIONAL PERFORMANCE
Get PDFPublic Procurement is one of the major objectives of any government striving to deliver goods and services to its people. Indeed, procurement permeates the entire spectrum of the development process since the government is a major purchaser of goods and services that entails the application of colossal amounts of money running into billions of shillings. If the procurement process is not transparent and efficient, it results in the loss of taxpayers’ money which in turn reverses the gains made withthe attendant consequences of poverty, insecurity, poor infrastructure, inadequate health services among others. Unfortunately the foregoing scenario has characterized public procurement in many countries over the years. In an attempt to address these weaknesses, various governments have tailor made legal framework to provide an efficient system of procurement. This paper therefore makes an attempt to look a the implication of the legal framework, implementation challenges and organisational performance. The paper is basically a conceptualization of the study variables and explores a spectrum of various studies with a view to establish knowledge gaps in compliance of public procurement of legal framework in different contexts.Key Words: Public Procurement, Legal Framework, Implementation Challenges, Organisational Performance, Enforcemen
Phytochemical Evaluation and In Vitro Antibacterial Activity of Methanolic-Aqua Extract of Indigofera arrecta Leaves against selected Pathogenic Microorganisms
No full textBackground: The continued emergence of drug resistant microorganisms has always been a concern to scientists and pharmaceutical companies. Plants have shown great potential in the fight against this challenge, therefore creating the need for scientist to turn in to plants to get new antimicrobial agents. Objective: The objective of the current study was to qualitatively analyze the phytochemical composition and the antibacterial activity of aqueous methanolic extracts of Indigofera arrecta leaves. Methodology: The plant samples were extracted using methanol-water solvent system. The phytochemical analysis was done using standard procedures while the bioassay study was done using well diffusion method. Results: The plant extract was found to contain all tested phytochemicals. The plant extract inhibited the growth of all the microorganisms tested. Bacillus cereus had the highest zone of inhibition while Escherichia coli was the least inhibited. Discussion: The plant extract inhibited the growth of all the bacteria tested, suggesting the presence of antibacterial compounds in the extract. However further research needs to be done to isolate these active compounds and perform in vivo studies to investigate their mode of action, safety and dosage. Key words: phytochemical, antibacterial, plant extract, Indigofera arrect