Inhibitor Effect (Lipid and Protein) in Starch Hydrolysis to Produce Glucose by using Amyloglucosidase

Abstract

Microalgae contains approximately 24 % of starch which is potential for bioethanol feedstock by enzymatic hydrolysis. The problem is that starch in microalgae is accumulated with protein and lipid, while the interaction of starch-protein and starch-lipid might inhibit enzymatic hydrolysis of starch. Native starch, isolate protein and palmitic acid are used to investigate the interaction effects of starch-protein and starch-lipid in microalgae. This study aimed to investigate effects of protein and lipid concentration (1:0, 1:0.05, 1:0.1, 1:0.25, 1:0.5, 1:1) (w/w) added into native starch hydrolysis by amyloglucosidase enzyme were incubated at 45°C for 3 hours. The product of hydrolyzed was determined as glucose with spectrophotometer UV-Vis at 540 nm. The result shows that the increasing of protein and lipid concentration added into starch granule will significantly (P<0.05) decrease concentration of glucose product. The kinetic parameters are evaluated by Michaelis-Menten models for uncompetitive inhibition.