新食品原料壳寡糖的酶法生产研究

Enzymatic preparation of chitooligosaccharide, a new food raw material

中文关键词:  新食品原料  壳寡糖  壳聚糖酶  清洁生产  应用推广

英文关键词:new food raw material  chitooligosaccharide  chitosanase  cleaner production process  application and popularization

中文摘要:

      目的 本论文针对高分子原料壳聚糖在食品工业应用中的难题——清洁生产与安全食用两大问题，研究了内切壳聚糖酶EC.3.2.1.132在新食品原料壳寡糖工业生产中的应用。 方法 通过广泛筛查，选育产酶活性高、性能稳定、具有单一内切模式的野生菌种。综合应用生物工程技术构建高效表达的基因重组工程菌，经优化发酵条件、建立简易纯化方法，获得了专一性内切壳聚糖酶。采用循环型清洁生产工艺用于新食品原料壳寡糖的工业化生产。 结果 从产酶量10U/mL左右的野生型曲霉菌株Jxsd-01获得成熟基因，构建重组毕赤酵母工程菌表达体系，内切壳聚糖酶蛋白产量达到0.95g/L。采用循环型清洁生产工艺酶法生产的壳寡糖含量高达98%，聚合度n = 2～10，原料转化率95%以上，生产过程中无废水、废渣产生。结论 内切壳聚糖酶应用于食品工业，实现新食品原料壳寡糖的工业化酶法生产，达到清洁、安全、高效的效果，具有应用推广的价值。

英文摘要:

      Objective To solve the problem of the applications of chitosan, which is a polymer, in food industry, we focused on two issues: the cleaner production process and the food security. The characters of endo-type chitosanase EC.3.2.1.132, and its applications were studied in the production of chitosan saccharide, a new food raw material. Methods Through the extensive screening, a strain with high enzyme activity and stable performance was got, then the endo-type chitosanase was purified . By various methods of biological engineering technology, we built a recombinant engineering yeast, which can efficiently express the aimed enzyme after the optimization of fermentation conditions, and then a simple and easy purification method was established, with a circular cleaner production process, and was applied to the industrial production of the chitosan saccharide, a new food raw material. Results The wild type Aspergillus strains Jxsd -01 could produce enzyme about 10 U/mL, and the recombinant of the gene in the engineering yeast could improve the expression system, the enzyme protein expression was 0.95 g/L. The content of the chitosan saccharide in enzymatic production was as high as 98%, with the polymers from 2 to 10. The conversion rate of raw material was more than 95%, without waste water or waste residue in the process of production. Conclusion The application of endo-type chitosanase in food industry can make the production process of the chitosan saccharide cleaner, safer and more efficient, so it has the value of wide application.