壳聚糖载体的改性及其用于固定化漆酶的研究

利用有机酸改性壳聚糖,并用交联法制备酸化的壳聚糖载体,然后用改性壳聚糖载体固定漆酶。甲酸、乙酸改性壳聚糖的最适条件:壳聚糖与甲酸、乙酸的质量摩尔比(g/mol)分别为100∶1、100∶1.5,戊二醛的质量分数为1%,缓冲溶液的pH分别是4.4、5.0,反应时间为3h;壳聚糖与酒石酸、草酸的质量摩尔比(g/mol)分别为100∶0.5、100∶2,戊二醛的质量分数为2%,缓冲溶液的pH分别是3.6、4.2,反应时间为4.5h。不同有机酸改性的壳聚糖用于漆酶的固定,其酶活都有不同程度的提高,尤其用酒石酸改性的壳聚糖载体效果最好,其酶活提高了57%。

Modification of chitosan carrier for immobilization of laccase

Chitosan was modified with organic acid and cross-linked by acidification.Laccase was immobilized on the cross-linked chitosan carrier.Experimental parametres were as follows：orgacin acids were formic acid and acetic acid,molar ratios of chitosan to acid were 100∶1（g/mol）and 100∶1.5（g/mol）,the concentration of glutaraldehyde was 1%,the pH values were 4.4 and 5.0,reaction time was 3 h.In case of tartaric acid and oxalic acid,chitosan to acid ratios were 100∶0.5（g/mol）and 100∶2（g/mol）,glutaraldehyde concentration was 2%,pH values were 3.6 and 4.2,reaction time was 4.5 h.The activities of immobilized laccase were improved by varied conditions.Tartaric acid modification showed that the activity increased by 57%.