Purification and Characterization of α-Amylase from Honeydew Honey

Abstract

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.

Keywords:

• Pure honey from honeydew
• α-Amylase
• Purification
• Characterization