非特异性酶对改性几丁质的降解能力及其产物分析  

Degradation Capacity of Non-specific Enzyme for Modified Chitin and Product Analysis

作　　者：刘洋[1] 郭明珠 石文琪 尹朝阳 桑亚新[1] 孙纪录[1] Liu Yang;Guo Mingzhu;Shi Wenqi;Yin Zhaoyang;Sang Yaxin;Sun Jilu(College of Food Science and Technology,Hebei Agricultural University,Baoding 071000,Hebei;College of Food Science and Technology,Hebei Normal University of Science&Technology,Changli 066600,Hebei)

机构地区：[1]河北农业大学食品科技学院,河北保定071000 [2]河北科技师范学院食品科技学院,河北昌黎066600

出　　处：《中国食品学报》2023年第4期192-200,共9页Journal of Chinese Institute Of Food Science and Technology

基　　金：河北省省级科技计划资助项目(19273201D);河北省现代农业产业技术体系淡水养殖创新团队建设项目(HBCT2018180206)。

摘　　要：由于天然几丁质具有分子质量高,结晶度高,不易酶解的特点,因此其开发和应用受到极大地限制。为了提高几丁质的利用率,筛选具有高降解能力与良好经济效益的商品化非特异性酶,并评价其对经3种改性方法(超微粉碎、高压均质、超微粉碎-高压均质联用)处理的几丁质的酶解效果,确定最佳改性方式,优化酶解工艺,分析酶解产物。结果表明:7种非特异性酶中,木瓜蛋白酶的几丁质降解能力最高,成本最低廉。超微粉碎-高压均质联用法使几丁质具有更高的可降解性。木瓜蛋白酶对几丁质降解的最佳条件:温度50℃,pH 7.0,酶质量浓度10 mg/mL,时间14 h。薄层层析结果显示,在酶解初期(1 h)生成(GlcNAc)3-6共4种聚合度的几丁寡糖,初步证明木瓜蛋白酶能够断裂几丁质的β-1,4糖苷键。离子色谱分析结果显示,酶解平衡(14 h)后的酶解产物中只有GlcNAc和(GlcNAc)2,质量浓度分别为22.26 mg/mL和58.75 mg/mL。Natural chitin has the characteristics of high molecular weight,high crystallinity and difficult enzymatic hydrolysis,which greatly limits its development and application.In order to improve the utilization rate of chitin,commercial non-specific enzymes with high degradation ability and good economic benefits were screened in this study,and their enzymatic hydrolysis effects on chitin after three modification methods(ultra-micro grinding,high-pressure homogenization,ultra-micro grinding-high-pressure homogenization)were evaluated.Determine the best modification method,optimize enzymatic hydrolysis process and analyze enzymatic hydrolysis products.The results showed that among the seven non-specific enzymes,papain had the highest chitin degradation ability and the lowest cost.The combined pretreatment of ultra-micro grinding and high-pressure homogenization method made chitin have higher degradability,the optimum conditions for degradation of chitin by papain were temperature 50℃,pH 7.0,enzyme mass concentration 10 mg/mL,time 14 h.The results of thin layer chromatography showed that(GlcNAc)3-6 four degrees of polymerization of chitin oligosaccharides were produced at the initial stage of enzymatic hydrolysis(1 h),which preliminarily proved that papain could break theβ-1,4 glycosidic bond of chitin;the results of ion chromatography analysis showed that only GlcNAc and(GlcNAc)2 were found in the enzymolysis products after enzymolysis equilibrium(14 h),and the mass concentrations were 22.26 mg/mL and 58.75 mg/mL,respectively.

关 键 词：木瓜蛋白酶 几丁质 超微粉碎 高压均质 几丁寡糖 

分 类 号：TS254.9[轻工技术与工程—水产品加工及贮藏工程]