Enzymatically Hydrolyzed Water-Soluble Chitosan as a Potent Anti-Microbial Agent

Abstract

Biological activities of chitosan depend upon its degree of polymerization (DP), fraction of acetylation (FA), and possibly on their pattern of acetylation (PA). Active molecular weight chitosan (AMC) was obtained from water soluble chitosan (WSC) by enzymatic hydrolysis over 600 h of time period. By the end of hydrolysis WSC was hydrolyzed to AMC with final concentration of 14 mM of reducing sugars with lowest viscosity (1.99 mm(2)/sec). Matrix assisted laser desorption/ionization-time of flight mass spectrometer (MALDI-TOF) analysis has shown homo- and hetero-oligomers in the reaction mixture. Intense infra-red (IR) bands appeared through 500-3700 cm(-1) were assigned to be asymmetric and symmetric stretching of common sugars. WSC-AMC has inhibited 80% growth of Candida albicans and Penicillium italicum with highest zone of inhibition of 22 and 25 mm respectively. Mechanism of action for cellular growth inhibition involves the reactive oxygen species (ROS) elimination beyond the normal levels along with inactivation of -lactamase like enzymes. Our results demonstrated that after hydrolysis the biological activities of WSC improved along with its flow properties and other biological activities.