外切菊粉酶的酶学研究进展

Advances in Enzymology of Exo-Inulinases

菊粉富含于菊芋、菊苣等多种菊科植物中,是一种来源丰富的可再生资源。菊粉是一种由D-呋喃果糖经β-2,1-糖苷键连接,还原端经α-1,2-糖苷键连接1个葡萄糖残基构成的果聚糖。菊粉能被菊粉酶水解,生产果糖、高果糖浆、菊粉寡糖,可通过微生物发酵生产燃料酒精等产品,在食品、生物能源、医疗保健等方面都有重要应用,受到广泛关注。介绍外切菊粉酶的分类、来源、结构和催化机理,重点总结近10年微生物来源外切菊粉酶的重组表达和酶学性质情况,简述外切菊粉酶在食品、能源等方面的应用,展望外切菊粉酶的研究热点及方向。

Inulin is rich in a large variety of Compositae plants such as Jerusalem artichoke(Helianthus tuberosus)and chicory(Cichorium spp.),and is a renewable resource with abundant sources.Inulin is a fructan composed of D-furan fructose linked by β-2,1-glycoside bond and with a glucose residue at reducing end linked byα-1,2-glycoside bond.Inulin can be hydrolyzed by inulinases to produce fructose,high fructose syrup,and inulin oligosaccharide and fuel alcohol by microbial fermentation.It has important applications in food,bioenergy and health care,and has received extensive attention.Recently researchers have discovered a number of exo-inulinases and studied their enzymatic properties.This paper introduces the classification,source,structure and catalytic mechanism of exo-inulinases,stresses on summarizing the recombinant expression and enzymatic properties of microbial-derived exo-inulinases in recent ten years,and briefly describes the applications of exo-inulinases in food and bioenergy.The research hotspots and directions of exo-inulinases are prospected.