INHIBITORY EFFECT OF Areca catechu & Nicotiana tabacum EXTRACTS ON THE ACTIVITY & KINETICS OF SALIVARY AMYLASE ENZYME
DIP JYOTI HALOI *
Department of Zoology, Handique Girls’ College, Guwahati, Assam, India.
POULOMI DHAR
Department of Zoology, Handique Girls’ College, Guwahati, Assam, India.
INNIFA HASAN
Department of Zoology, Handique Girls’ College, Guwahati, Assam, India.
*Author to whom correspondence should be addressed.
Abstract
Amylases are a group of enzymes that catalyze the hydrolysis of glucosidic bonds present in starch and related polysaccharides. In the present study, the enzymatic activity and kinetics of the human salivary amylase is studied at different substrate concentrations. The substrate concentrations considered in the experiment were 0.10%, 0.30%, 0.50% and 0.70%. With the increase in substrate concentration, the velocity of the reaction increased up to its highest level (i.e., a Vmax of 931.80 U/dL) and thereafter the enzyme velocity was reduced. The Km (Michaelis constant) value of amylase activity is found to be 0.07242 U/dL from the Line weaver-Burk plot.
At 0.50% substrate concentration the mean amylase activity obtained is 931.25 U/dL. The mean enzyme activity is found to be 402.65 U/dL and 477.12 U/dL with the addition of Areca catechu & tobacco extract respectively. The Areca nut and tobacco extract suppressed the amylase activity to a significant extent. The Vmax and Km values of amylase with Areca catechu extract are found to be 322.5 U/dL and 0.03306 U/dL respectively. The Vmax and Km values with another inhibitor Nicotiana tabacum are found to be 546.2 U/dL and 0.1198 U/dL respectively. Amylase inhibitors are known as starch blockers because they prevent dietary starches from being digested and absorbed by the body. The polyphenols present in these components bind readily to the protein and cause inhibition.
Keywords: Amylase, kinetics, Areca catechu, Nicotiana tabacum, starch