Biological activities of leaves of ethnomedicinal plant, Borassus flabellifer Linn. (Palmyra palm): An antibacterial, antifungal and antioxidant evaluation

Plants contain a variety of phytochemicals that have the ability to exert effect on human body. Among them Borassus flabellifer Linn. is a medicinally important plant. In traditional medicine different parts of plants are being used for their medicinal properties. The methanol extract was obtained from powdered leaves and further fractions were prepared. Antimicrobial potential was investigated using eight pathogenic strains of bacteria and fungi by agar well diffusion method. Broth dilution method was employed to MIC and MMC of active samples and MIC index value was determined. ME was subjected to preliminary phytochemical analysis; and 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2) radical scavenging activity. Phytochemical screening revealed the presence of several phytochemicals. The ME showed dose dependent radical scavenging activity as evidenced by IC50 values for DPPH (40.19 μg/ml) and H2O2 (30.92 μg/ml) radicals. The inhibition zones and MIC values for bacterial strains were in the range of 10–16 mm and 50–70 μg/ml, respectively. All the samples showed an inhibitory effect on fungal strains with inhibition zone (10–17 mm) and MFC (50–70 μg/ml). Samples exhibited diverse patterns of antibacterial and antifungal effects. Among the tested samples, methanol extract and acetone fraction (AF) had potent antibacterial and antifungal activities. These results lead to the conclusion that the plant has a broad spectrum antimicrobial and antioxidant activity and could be a potential option for treating various infectious diseases. The strong antioxidant property of methanol extract might be employed in the development of natural antioxidants for agro-food and pharmaceutical industries