Alpha-Amylase Inhibition Activity of Endophytic Fungi Isolated from Leaves of Artocarpus heterophyllus

The present study aimed to investigate the alpha-amylase inhibition activity of endophytic fungi isolated from the senescent leaves of Artocarpus heterophyllus. Surface sterilized leaf segments were placed on potato dextrose agar (PDA) and malt extract agar base (MEAB) media. Primary fungal cultures were sub-cultured to obtain the pure cultures. Ethyl acetate fungal extracts were tested using the alpha-amylase inhibition assay. The highest active fungal extract was subjected to bio assay guided fractionation and the percentages of alpha-amylase inhibition of those fractions were also determined. Three different endophytic fungi were isolated using the PDA and MEAB. The highest antidiabetic active fungal extract showed 892.0 % alpha-amylase inhibition activity at 5000 ppm which was higher than that of the standard drug acarbose (71 2.5 %) at 5000 ppm. The highest antidiabetic active fungal extract also showed an increasing alpha-amylase inhibition activity when concentration was increased from 1000 ppm to 5000 ppm. Four fractions were obtained by normal phase silica gel column chromatography, based on the TLC profiles. Out of them three fractions showed more than 50 % alpha-amylase inhibition activity at 5000 ppm concentration. This study showed that the ethyl acetate crude extract of isolated endophytic fungus showed promising antidiabetic activity.