ANTIMICROBIAL ACTIVITY OF GRAPEFRUIT'S (CITRUS PARADISI) ESSENTIAL OIL AND METHANOLIC EXTRACTS OF PULP, PEEL, AND SEED

The essential oil from the fresh grapefruit peels was extracted by the hydrodistillation method. The methanolic extracts of dried and powdered grapefruit pulp, peel, and seed were prepared by using methanol as a solvent. The antimicrobial activity of essential oil and methanolic extracts of grapefruit’s pulp, peel and seed were determined by using the disc diffusion method against bacteria (Salmonella Typhi, Escherichia coli, Staphylococcus aureus) using streptomycin as standard and against fungi (Aspergillus niger, Aspergillus terreus, Alternaria alternata) using 1% fluconazole as standard. The results showed that the essential oil and the methanolic extracts of grapefruit’s pulp, peel, and seed exhibited zones of inhibition against bacteria Salmonella Typhi were 27mm, 25mm, 8mm, and 5mm, Escherichia coli were 24, 20mm, 7mm, and 9mm, Staphylococcus aureus were 19mm, 17mm, 5mm, and 6mm and against fungi Aspergillus niger were 40mm, 39mm, 16mm, and 18mm, Aspergillus terreus were 29mm, 17mm, 22mm, and 23mm and Alternaria alternata were 23mm, 18mm, 17mm, and 22mm respectively.