毛壳霉木聚糖酶B(CsXyn11B)的分泌表达及其在面包中的应用  

Secretion Expression of Xylanase B(CsXyn11B) from Chaetomium sp.and Its Application in Bread

作　　者：杨行 马俊文 李延啸[1] 江正强[2] 刘学强 闫巧娟[1] YANG Hang;MA Junwen;LI Yanxiao;JIANG Zhengqiang;LIU Xueqiang;YAN Qiaojuan(College of Engineering,China Agricultural University,Beijing 100083,China;College of Food Science and Nutritional Engineering,China Agricultural University,Beijing 100083,China)

机构地区：[1]中国农业大学工学院,北京100083 [2]中国农业大学食品科学与工程学院,北京100083

出　　处：《食品工业科技》2023年第4期108-113,共6页Science and Technology of Food Industry

基　　金：国家重点研发计划(2021YFC2103004)。

摘　　要：目的:对毛壳霉(Chaetomium sp.)CQ31木聚糖酶B(CsXyn11B)进行分泌表达,以提高产酶水平并探究在面包烘焙中的应用价值。方法:将木聚糖酶基因在毕赤酵母中表达,高密度发酵提高其产酶水平,对酶学性质进行表征并将其应用在面包烘焙中。结果:重组菌经高密度发酵156 h,木聚糖酶酶活力为2788 U/mL。CsXyn11B最适pH为8.0,最适温度为65℃。CsXyn11B能够水解多种木聚糖底物,对燕麦木聚糖、小麦阿拉伯木聚糖、榉木木聚糖和桦木木聚糖的比酶活分别为1145.8、1041.7、692.3和653.3 U/mg。该酶水解阿拉伯木聚糖,水解产物以聚合度4~6的低聚木糖为主。在面包制作过程中加入3 mg/kg CsXyn11B使面包比容增加15.9%,面包硬度降低25.3%,4℃贮藏2 d后硬度比对照组降低17%。结论:毛壳霉木聚糖酶B的优良酶学特性使其在烘焙食品中具有良好的应用前景。Objective:A xylanase B(CsXyn11B)gene from Chaetomium sp.CQ31 was extracellularly expressed to improve the enzyme production and explore its application in bread baking.Methods:The xylanase(CsXyn11B)gene was expressed in Pichia pastoris,and the enzyme production was improved by high-density fermentation.The enzymae was characterized and applied in bread baking.Results:The recombinant strain was fermented at high density for 156 h,and the enzyme activity of xylanase was 2788 U/mL.The optimal pH of CsXyn11B was pH8.0,and the optimal temperature was 65℃.CsXyn11B hydrolyzed a variety of xylans,and the specific enzymatic activities of oat xylan,wheat arabinoxylan,beech xylan and birch xylan were 1145.8,1041.7,692.3 and 653.3 U/mg,respectively.The enzyme hydrolyzed arabinoxylan,and the hydrolyzed product were mainly xylo-oligosaccharides with a degree of polymerization of 4~6.Addition of CsXyn11B(3 mg/kg)into the bread making remarkably improved the specific volume by 15.9%and decreased the hardness by 25.3%.Compared with the control group,the hardness decreased by 17%after storage at 4℃for 2 d.Conclusion:The excellent properties of xylanase B from Chaetomium sp.made it have a promising application prospect in baked food.

关 键 词：毛壳霉 木聚糖酶 毕赤酵母 高密度发酵 面包 

分 类 号：TS213.2[轻工技术与工程—粮食、油脂及植物蛋白工程]