HARNESSING COCONUT HUSK: SOLVENT-BASED EXTRACTION AND ITS ANTIMICROBIAL ACTIVITY AGAINST FOODBORNE PATHOGENS

Abstract

Natural sources of antimicrobial agents have gained attention as antibiotic resistance continues to threaten global health. Coconut husk, a renewable agro-industrial byproduct rich in phenolics, flavonoids, and tannins, demonstrates antimicrobial properties. This study evaluates coconut husk extracts prepared with ethanol, methanol, and water solvents for antimicrobial activity against four food borne pathogens including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi. The ethanol extract showed significant antimicrobial activity, particularly at 48 hours, producing the largest inhibition zones (up to 29 mm for P. aeruginosa), due to its ability to extract a broader range of bioactive compounds. Methanol and water extracts showed moderate activity but were less effective compared to ethanol. Structural changes observed in microbial cell membranes after coconut husk extraction were confirmed by SEM, which indicated disruption of cellular integrity as mode of action of the antimicrobial activity. Active compounds present in phytochemical analysis confirmed to be alkaloids, tannins, flavonoids, and phenolics. The antimicrobial activity of coconut husk extracts indicating their potential to use in food preservation reducing pathogen load and extending shelf life.