Total phenolic content, reducing power, antioxidative and anti-amylase activities of five Bangladeshi fruits

Phenolic content, antioxidant and anti-amylase activities were studied in the ethanolic extract of five available Bangladeshi fruits. The fruits were Averrhoa bilimbi (Bilimbi), Artocarpus lacucha (Monkey jack), Cucumis melo (Mask melon), Phoenix sylvestris (Wild date palm) and Flacourita jangomas (Indian plum). P. sylvestris had the highest total phenolic content (37.40 ± 1.72 mg GAE/10 g of extract), whereas C. melo had the lowest (6.02 ± 0.89 mg GAE/10 g of extract). All the fruits showed DPPH free radical scavenging activity with the IC50 values for P. sylvestris, A. lacucha, F. jangomas, C. melo and A. bilimbi were 1.90 μg/ml, 0.798 mg/ml, 1.144 mg/ml, 1.695 mg/ml and 3.683 mg/ml respectively. Highest level of reducing activity was found in P. sylvestris (O.D. 0.933 ± 0.02) and reducing power activity was lowest in A. bilimbi (O.D. 0.249 ± 0.01) at a concentration of 0.4 mg/ml. But all the fruits showed a dose-dependent increase in reducing power. The fruit extracts showed very weak inhibition of α-amylase activity. But highest activity found in case of P. sylvestris was 11.88 ± 3.69% and the lowest activity found for F. jangomas was 3.33 ± 0.64%. Considering the data, it can be concluded that among the five fruits P. sylvestris is the most health beneficiary.