IOSR Journal of Dental and Medical Sciences (IOSR-JDMS) e-ISSN: 2279-0853, p-ISSN: 2279-0861.Volume 13, Issue 4 Ver. V. (Apr. 2014), PP 29-32 www.iosrjournals.org www.iosrjournals.org 29 | Page Antimicrobial Effects of Bitter Kola (Garcinia Kola) Nut on Staphylococcus Aureus, Eschererichia Coli and Candida Alibicans *Amalu Paul C 1 .,Chukwuezi Fabian O. 1,2 And Ugwu Okechukwu P.C 3 . 1 Department Of Medical Laboratory Sciences, Faculty Of Health Sciences And Technology College Of Medicine, University Of Nigeria, Nsukka. 2 Department Of Biological Sciences, Faculty Of Applied And Natural Sciences, Tansian University, Umunya. 3 Department Of Biochemistry, Tansian University, Umunya. Abstract: This study was conducted to test for the antimicrobial activity of Garcinia kola (Aku-inu) against some microbial organisms, namely: Staphylococcus aureus, Escherichia coli and Candida albicans. The paper disc method was used to determine the inhibitory effect of Garcinia kola nut on the test micro-organisms. The zones of inhibition for Staphylococcus aureus ranged between 0.5 to 5mm for the ethanol preparation of Garcinia kola nut while that of E. coli ranged between 0.3 to 3.2mm. The ethanol preparation of Garcinia kola nut was found to exhibit more significant inhibitory action against test organisms than the aqueous preparations of Garcinia kola nut. Staphylococcus aureus in both preparations gave wider zones of inhibition than E.coli while Candida albicans exhibited no response. Minimal zones of inhibition started from 40% ethanol and diameter of inhibition increases with increase in ethanol concentration for E.coli, while Staphylococcus aureus started from 20% ethanol increasing in diameter as the concentration of ethanol increases. Candida albicans showed no zone of inhibition. Minimal zones of inhibition for the different weights of Garcinia kola nut/disc in 1ml of aqueous preparation of Garcinia kola nut started from the discs containing 300μg and 400μg for Staph. aureus and E. coli respectively, with diameters of 0.3mm and 0.4mm. Candida albicans showed no response to the different weights of Garcinia kola nut per ml of water. Statistically, results showed that ethanol preparation of Garcinia kola nut exhibit more significant activity (p<0.001) than the aqueous preparation of Garcinia kola nut (p<0.01). The results of the Garcinia kola nut may be attributed to the presence of some pharmacokinetic compounds. Keywords:Garcinia kola, Candida albicans, Staphylococcus aureus, E.coli and Minimal zones of inhibition. I. Introduction The Nigeria climate favours a great array of plant species many of which have varied medicinal and antimicrobial potentials [1, 2, 3, 4 and 5]. It is estimated that there are over 65,000 species of flowering plants that have medicinal properties [6, 7, 8, 9 and 10]. In African, medicinal plants constitute a rich but still largely untapped pool of natural products. Many countries from the developing world are still dependent on medicinal plants for treating the sick among them. Globally, the last two decades has witnessed an unprecedented increase of drug resistance by pathogenic micro-organisms as well as the appearance of undesirable side effect of certain antibiotics [11 and 12]. Other limitations of modern chemotherapeutic drugs are their high cost and non- availability, especially in rural areas. As a consequence, it is necessary to search for new organic molecules with antimicrobial activity, which in addition could be potential sources for starting materials for the semi-synthesis of new drugs [12 and 13]. Traditional medicine practice is an important part of health care delivery system in most part of the developing world [14, 15, 16 and 17] and is a source of primary health care to 80% of the worlds’ population [18 and 19]. Traditional medical knowledge of medicinal plants and their use by indigenous culture are not only useful for conservation of cultural traditions and biodiversity but also for community healthcare and drug development now and in the future [20, 21, 22 and 23]. Traditional herbalist in Nigeria uses a variety of herbal preparation to treat different kinds of ailmentssuch as gonorrhea, sore throat and skin infections like eczema. This has been the case ever before the introduction of antibiotics and other modern drugs into Africa [24, 25, 26, 27 and 30]. According to the World Health Organization (WHO), up to 80% of the population in Africa depends on traditional herbal medicine for primary health care, accounting for around 20% of the overall drug market [31 and 32]. A number of plants that have medicinal and antimicrobial properties in Nigeria have been identified and documented [33 and 34]. World- wide increase in resistance to antibiotics has prompted scientists and researchers to seek for other possible potential antimicrobials [35 and 36]. Due to this search, plants have been seen as a good source of antimicrobial agents[37]. Some of the active ingredients of the extracts of some plants have been isolated, tested and documented [4 and 8]. The clinical efficacy of many existing antibiotics is being threatened by the emergence of multidrug- resistant pathogens. The increasing failure of chemotherapeutic and antibiotic resistance exhibited by pathogenic