β-葡聚糖酶降解魔芋葡甘聚糖产物的制备及结构表征  

Preparation and Structural Characterization ofβ-Dextranase Hydrolytic Products of Konjac Glucomannan

作　　者：阙凤 夏雨婷 高天麒 汪超 汪兰 熊光权[2] 石柳[2] 丁安子 吴文锦[2] QUE Feng;XIA Yuting;GAO Tianqi;WANG Chao;WANG Lan;XIONG Guangquan;SHI Liu;DING Anzi;WU Wenjin(School of Biological Engineering and Food,Hubei University of Technology,Wuhan 430068,China;Institute of Agricultural Products Processing and Nuclear Agricultural Technology,Hubei Academy of Agricultural Sciences,Key Laboratory of Agricultural Products Cold Chain Logistics,Ministry of Agriculture and Rural Affairs,Wuhan 430064,China)

机构地区：[1]湖北工业大学生物工程与食品学院,湖北武汉430068 [2]湖北省农业科学院,农产品加工与核农技术研究所,农业农村部农产品冷链物流技术重点实验室,湖北武汉430064

出　　处：《食品科学》2023年第8期9-15,共7页Food Science

基　　金：国家自然科学基金面上项目(31871870);湖北省青年拔尖人才培养计划项目。

摘　　要：魔芋葡甘聚糖(konjac glucomannan,KGM)可被β-葡聚糖酶降解,对其降解产物的结构特性进行了研究。利用X射线衍射、傅里叶变换红外光谱、扫描电子显微镜鉴定KGM及其酶解产物的结构特征变化,并结合多角度激光光散射-凝胶渗透色谱法测定KGM及其产物的分子质量,测定其特征黏度、脱乙酰度、可溶性多糖含量、电学特性等对酶解产物进行化学特性评估。结果表明:与原KGM相比,KGM酶解产物的主链结构没有改变,原KGM经过5倍酶量酶解120 min后,可能存在较弱的结晶区,扫描电子显微镜结果显示酶解产物表面片层化,且分子质量减小至(36.48±1.23)kDa,特征黏度减小了98%,脱乙酰度显著增大(P<0.05),可溶性总糖含量显著降低(P<0.05)。本研究可为KGM酶解改性的应用提供参考,促进KGM酶解产物资源的高价值利用。Konjac glucomannan(KGM)was degraded byβ-glucanase.The structural characteristics of KGM and its hydrolysate were identified by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR)and scanning electron microscopy(SEM),and their molecular masses were determined by gel permeation chromatography with multiple angle laser light scattering.The chemical characteristics of the hydrolysate were evaluated by measuring their intrinsic viscosity,deacetylation degree,soluble polysaccharide content and electrical characteristics.The results showed that the major chain structure of the hydrolysate did not change compared with KGM.After 120 min of treatment with a five-fold excess of the enzyme,a weak crystalline region may appear.SEM results showed that the surface of the hydrolysate gradually became lamellated,and its molecular weight decreased to(36.48±1.23)kDa.The characteristic viscosity decreased by 98%,the degree of deacetylation increased significantly(P<0.05),and the content of total soluble sugar decreased significantly(P<0.05).This study can provide a reference for the enzymatic modification of KGM to promote the high-value utilization of KGM hydrolysate resources.

关 键 词：魔芋葡甘聚糖 酶解改性 微观结构 化学特性 

分 类 号：TS201.7[轻工技术与工程—食品科学]