Production and Separation of Chitooligosaccharides using Capsicum annuun Immobilized Chitosanase

Abstract

ABSTRACT The products of chitosan hydrolysis are chitooligosaccharides and are used mainly for medical applications due to their specific biological activities. The objective of this study was to prepare and separate chitooligosaccharides (COS N )from chitosan using Capsicum annuum immobilized chitosanase. We firstly studied the optimal reaction conditions, in order to maximizethe production of COS N by using immobilized chitosanase. The optimal temperature and pH for COS N production were determined to be 55°C and pH 5.6. The ratio of enzyme /substrate should not be lower than 0.95 U/mg in reaction mixture for maximal COS N production. From the time course of the enzymatic degradation of soluble chitosan, it was found that the hydrolysis rate was fast during the first 1.5 h. In the following reaction time, no significant change occurred. The immobilized chitosanase could be recovered and reused repeatedly for four times with high COS N production. Relative COS N production at optimum hydrolysis conditions was 55.21 %.The prepared COS N was separated by ultrafiltration to four fraction (I, II, III and IV) according to the molecular weights (>100, 100-10, 10-1 and <1KDa, respectively). The total yield recovery after separation by ultrafiltration was 100%. Fraction II and III with COS N yield of 33.5 % and 31.3 % and COS ratio of 18.31 % and 49.72%, respectively were higher than that of fraction I and IV