RESUMO
α-glucosidase (EC: 3.2.1.20) from Penicillium chrysogenum Thom ATCC 10106 was induced by GSH at the lower concentrations. H2O2 was inhibitor at all tested concentrations and the IC50 was 92.2%v/v. AMP, ADP and ATP enhanced the activity revealing that α-glucosidase is endothermic enzyme. The chelating agents are ethylenediaminetetraacetate (EDTA), α-α-dipyridyl and o-phenanthroline inhibited the enzyme. IC50 for these three compounds were 7.1, 10.2 and 10.9 mM, respectively. The highest activity of α-glucosidase was recorded at 150 mM phosphate buffer. Mannitol as polyol protected the enzyme against heat inactivation. The five sugars trehalose, lactose, raffinose, glucose and sucrose protected α-glucosidase against thermo-inactivation at 60ºC. Also, sarcosine as a product of glycine provided α-glucosidase with appreciable thermostability at 60ºC.