Studies on Structure and Function of Cellulase-Modified Soluble Dietary Fiber from Cyperus esculentus Meal
Utilizing Cyperus esculentus meal as raw material,soluble dietary fiber(SDF)was extracted from it using a composite enzyme method(α-amylase,glucoamylase and trypsin).The SDF was enzymatically modified by cellulase,and the enzymatic hydrolysis conditions of cellulase(enzyme addition amount,enzymatic hydrolysis temperature,enzymatic hydrolysis time,enzymatic hydrolysis pH value)were optimized.The content,physicochemical properties,structural char-acteristics and antioxidant capacity of SDF before and after modification were compared.The results showed that the opti-mum conditions for cellulase modification were as follows:pH 6.5,hydrolysis temperature 40 ℃,enzyme addition 0.9％,hydrolysis time 2.5 h,SDF content increased from 3.55％to 10.86％.By observing the ultrastructure,it was found that the modification changed the fiber structure,weakened the diffraction peak intensity,improved its structural characteris-tics,and improved the microstructure characteristics.In addition,cellulase modification increased the water holding ca-pacity,swelling capacity and oil holding capacity of Cyperus esculentus meal SDF by 54.58％,43.73％and 38.40％,re-spectively.When the mass concentration of SDF was in the range of 0.5-5 mg/mL,the scavenging ability of modified SDF on 1,1-diphenylpicrylhydrazyl(DPPH)radical,2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)rad-ical,hydroxyl radical(·OH)was significantly improved.The highest values were 42.87％,44.05％and 41.46％,and the ability to reduce Fe3+increased by 1.25 times at 5 mg/mL.This study provides a reference for further improving the de-velopment value of Cyperus esculentus meal and its application in human food and pharmaceutical industry.
NETL
NSTL
万方数据
