Purification and Characterization of α-Amylase from Honeydew Honey.

α-Amylase was extracted from honeydew honey and purified by CM-Toyopearl 650M and Toyopearl HW-55F column chromatographies. The molecular weight of the enzyme was estimated to be about 58 kDa by Toyopearl HW-55F gel chromatography and SDS-PAGE, respectively. The optimum pH was 4.0 and optimum temperature 50°C. Inactivation of the enzyme occured when the pH was higher than 8.0 or lower than 3.0. This enzyme activated by Ca2+ and Mn2+, but inhibited by Fe3+, Hg2+, Zn2+, and EDTA. TLC analysis also suggested that the purified enzyme was of the α-type. The relative rate of hydrolysis of the polymeric substance decreased with decreasing percentage of α-1,4-linkages and with increasing percentage of α-1,6-linkages in substrate. [ABSTRACT FROM AUTHOR]