Activators and Inhibitors of α-glucosidase from Penicillium chrysogenum
Hamed M. El-Shora *
Department of Botany, Faculty of Science, Mansoura University, Dakahlia, Egypt.
Mohsen E. Ibrahim
Department of Botany, Faculty of Science, Port Said University, Port Said, Egypt.
Mohammad W. Alfakharany
Department of Botany, Faculty of Science, Port Said University, Port Said, Egypt.
*Author to whom correspondence should be addressed.
Abstract
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.
Keywords: P. chrysogenum, glutathione, adenosine compounds, chelating agents, trehalose, mannitol.