Abstract
α-glucosidase (α-D-glucoside glucohydrolase, EC:3.2.1.20) was isolated from Penicillium chrysogenum Thom ATCC 10106. The enzyme was purified by ammonium sulphate precipitation (85%), DEAE-cellulose and Sephadex G-200. The final specific activity was 360 units/mg protein. The yield was 18 % and the purification fold was 52.9. Trehalose and different sugars offered appreciable protection of α-glucosidase against denaturation at 60 °C. The aqueous extracts from various plants including Trigonella foenum-grecum, Sinapis arvensis, Cucurbita moschata, Apium crispum and Lepidium sativum inhibited α-glucosidase activity with different rates. IC50 values of the tested plants extracts were 88.5, 65.3, 72.6, 84.7 and 97.9 μg/ml, respectively.