The Influence of Cysteine Addition on Papain Activity

Papain is a proteolytic enzyme derived from the juice of Carica papaya. It has the ability of hydrolyzing most of proteins. It has been developed as denture cleanser in attempt to break down the organic component of denture plaque. ”Objectives:” The aim of this research was to determine the influence of a reduction agent (cysteine) addition on papain activity in hydrolyzing casein substrate as a substitute of denture plaque. “Methods:” Papain (Merck®) 1mg/ml in PBS (pH 7.2) was prepared. The papain solution was added with cysteine (Merck®) by concentration of 0.01, 0.02, 0.03, and 0.04M respectively. Casein (Merck®) 1 % became the substrate of papain. The hydrolyzing activity of papain on the substrate was determined by Beynon and Bond Method (1989) in Tyrosine (TU)/mg unit. “Result:” The result revealed increasing in papain activity toward the substrate on the cysteine addition. The addition of 0.02M cysteine resulted papain maximum activity in hydrolyzing casein. The ANOVA showed there was a significant difference on papain activity among the addition of various cysteine concentration (p<0.05).”Conclusion:” Cysteine addition in papain solution influenced papain activity in hydrolyzing casein substrate as a substitute of denture plaque. Cysteine of 0.02M gave maximum papain activity.