壳聚糖的酶法降解产物分析

Analysis of the Enzymatic Hydrolysate of Chitosan

利用产壳聚糖酶菌株DES-4发酵产生的壳聚糖酶对壳聚糖底物进行酶法降解,测定了不同降解时间酶解产物的还原糖浓度及平均聚合度。结果表明:在温度为50℃、pH为5.5条件下酶解8h以后可得到聚合度小于10的壳寡糖混合物,12h酶解产物中还原糖浓度为3.87 mg/mL。利用纸层析法和高效液相色谱法(HPLC)对壳聚糖酶解产物进行分析,在纸层析图谱上,壳聚糖酶解液在原点与单体氨基葡萄糖的显色斑点之间均有显色,以单体氨基葡萄糖处的斑点较深。根据HPLC图谱分析,壳聚糖的12h酶解产物中氨基葡萄糖的含量达到80%以上。

Chitosanase from a Bacillus sp. DES -4 screened previously was used for enzymati＇c degradation of chitosan. Concentration of reducing sugar and average polymerization degree （ PD ） of the hydrolysate was measured after degradation by the chitosanse for different time. Results indicated that average polymerization degree was less than 10 after hydrolyzation for 8h and concentration of reducing sugar of the hydrolysate degraded for 12h reached 3.87mg/mL. Paper chromatography and high pressure liquid chromatography （ HPLC ） were used to analyze the hydrolysate of chitosan. On the paper chromatographic profile, color patterns of the hydralysate appeared from sampling point to the color pattern of monomer glucosamine, indicating that there exist monomer glucosamine and chito - oligosaccharides with different polymerization degree. Chromatographic profile of HPLC indicated that content of glucosamine in the hydrolysate of chitosan was more than 80%.