来源于Emericella rugulosa的新型内切菊粉酶基因挖掘、表达与功能表征OA

Fructooligosaccharide(FOS),as an important prebiotic,is experiencing continuously growing market demand,and there is a pressing need for the development of an efficient and low-cost production process.This study aims to mine novel endo-inulinase genes from microorganisms to achieve high-yield production of FOS.Five uncharacterized endo-inulinase genes were selected through gene min-ing,followed by cloning and recombinant expression using an E.coli expression system,after which their enzymatic properties were deter-mined.The results indicated that the recombinant endo-inulinase from Emericella rugulosa(ER-INU1)exhibited a significantly higher cat-alytic efficiency than the other four enzymes.ER-INU1 exhibited an optimal temperature range of 50-55℃and an optimal pH range of 5.0-6.0.Moreover,it retained over 85％of its initial activity after 4 hours of incubation at 50 ℃.Furthermore,using inulin as the sub-strate,the enzymatic hydrolysis conditions for ER-INU1 were optimized.The optimal reaction conditions for FOS production were deter-mined as follows:pH 5.5,temperature 50℃,substrate concentration 40 g/L,and enzyme dosage 40 U/g.Under these conditions,after 4 hours of reaction,ER-INU1 was able to efficiently catalyze the hydrolysis of inulin,producing FOS with a degree of polymerization ran-ging from 3 to 6 and achieving a yield as high as 95％.The enzyme demonstrated significant advantages in both catalytic efficiency and product specificity,showing promising potential for industrial applications.It provides an efficient enzymatic resource for the large-scale production of functional FOS.