In Vitro Antibacterial Activity and Phytochemical Screening of Garcinia Kola Extracts Against Methicillin Resistant Staphylococcus Aureus (MRSA)

Abstract

Modern medicines have always depended on herbal extracts from plants as fundamental source of therapeutic ingredients. The aim of the study was to determine the phytochemical constituents and antibacterial activity of Garcinia kola seed extracts against clinical isolates of Methicillin Resistant Staphylococcus Aureus (MRSA). Total of 107 Staphylococcus isolates from infected wound and urine and were collected from Abubakar Imam Urology Center in Kano State, Nigeria over a period of eight months (October 2015 to May 2016). A disc diffusion method was used for characterization of MRSA. The phytochemical screening of the plant materials was done using conventional laboratory method while the antibacterial activity of the plant extracts was determined using agar well diffusion method. The result of bacterial characterization showed that eight isolates found were to be Methicillin Resistant Staphylococcus aureus (MRSA). Phytochemical screening of the seeds, leaves and stem bark extracts indicated the presence of Alkaloid, Tannin, Saponin, and Cardiac glycoside, Flavonoid, Terpenoid, Phenols Anthraquinone and Steroid. However, reducing sugar is absent. The antibacterial activity of the plant showed that the plant part extracts demonstrated antimicrobial effect against the test isolates with higher activity in seeds compared to leaves and stem. Statistical analysis of the result revealed that the overall average zone of inhibition shown by the extracts is 11.68 mm with methanolic seeds extract exerting the highest antibacterial effects on the test isolates with average zone of inhibition of 12.78 mm, followed by methanolic leaf extract 12.37 mm then aqueous seed extract with zone of inhibition of 11.87 mm. Least zones of inhibition were recorded in aqueous leaf extract and methanolic stem back extract with zones of inhibition of 11.28 and 10.43 mm respectively. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the extracts range from 12.5 – 100 mg/ml of the extracts. Findings from this work support the use of seed extracts from G. kola as medicinal plant.