Physicochemical and Antibacterial Screening of Coconut Oil on some Clinical Bacteria Isolates

Abstract

Coconut (Cocos nucifera) is a palm tree found worldwide, mainly used as a staple food crop, source of wood, and in traditional medicine. This study investigates the physicochemical properties and antibacterial screening of coconut oil on some clinically isolated bacteria: Salmonella typhi, Staphylococcus aureus, Streptococcus pyogenes, and Escherichia coli from sputum, feces, and urine. The isolates were characterized based on biochemical tests according to standard methods. Coconut oil was extracted using the wet processing method, and physicochemical properties involving color, pH, moisture content, free fatty acid, and peroxide values were determined accordingly. These properties were found to fall within standard range values of the Association of Official Agricultural Chemists (AOAC). Agar-well diffusion assay was used for sensitivity assessment, and zones of inhibition diameters were measured in millimeters. Antibacterial activity of coconut oil was minimal at low volumes but demonstrated significantly appreciable antimicrobial effects on the test organisms with an increase in oil volume. The highest antimicrobial activity of 12.10 mm mean zone of inhibition diameter was observed for Staphylococcus aureus, followed by Streptococcus pyogenes with 10.13 mm, Escherichia coli with 6.96 mm, and Salmonella typhi with the lowest inhibition zone of 5.05 mm. Salmonella typhi showed a relatively low zone of inhibition even at higher volumes. Coconut oil has demonstrated antibacterial activity on the bacterial isolates used in this study and is a potential source of antimicrobial agent.