Abstract: In this work pectin hydrolysate was successfully prepared by using raw pectinase.The reaction conditions were designed and the methods for monitoring assay in the reaction process were discussed.The antibacterial activity of the enzymatic hydrolysate was investigated and a comparison with its acidic counterpart was made.The results showed that the viscosity and galacturonic acid contents of the reaction mixture could be correlated each other and both of these parameters could be applied for monitoring the process of pectin hydrolysis and the end of the reaction determination.The pectin hydrolysate,obtained by pectinase had inhibitory activity on Escherichia coli,Bacillus Sullilis,and Slaphylococcus eureus.Its MIC was 0.62%,however,pectin polymer and hydrolysate,obtained with acid,had no any similar activity at all.

Key words: pectin, pectinase, hydrolysate, antilbacterial activity