Effects Of Enzyme Cocktails On Degradation Of Non-starch Polysaccharides And In Vivo Nutrients Digestibilities Of Rice Bran

Synergic effects of main-chain enzymes and branched-chain enzymes in degradation of non-Starch polysaccharides from rice bran was studied,The results attempted to provide basic data for further studies to improve the nutrients utilization of rice bran.Experiment 1.Using ammonium sulfate fractionation,cationic(Q Sepharose FF) chromatography and size exclusion,arabinofuranosidase and acetyl xylan esterase was purificated from acidic xylanase and the neutral xylanase,The specific activity of arabinofuranosidase and acetyl xylan esterase was estimated to be 8.55IU/mg and 2.80 IU/mg,purification times is 16.76 and 9.3,coefficient of recovery is 5.43%,39.35%.Experiment 2.We take soluble non-starch polysaccharides,soluble non-starch polysaccharides degradated by phytase and Alkali-extractable insoluble non-starch polysaccharides as the substrate,according to the glycosyl profiles and the research results in our lab,we adopting orthogonal experiment methods to study studies the synergic effects of the main-chain enzymes(cellulase,xylanase,pectinase) and branched-chain enzymes (arabinofuranosidase,β-galactosidase,acetylxylan esterase) the amounts of reducing sugers was determined by DNS method,we use it to appraise degeneration effect.The results showed that:①Synergy between the main chain enzymes andβ-galactosidase was observed in the degradation of soluble non-starch polysaccharides and soluble non-starch polysa- ccharides degradated by phytase(P＜0.05),the same as acetylxylan esterase (P＜0.05),the best synergic effects manifests between main chain enzymes andβ-galactosidase.②Synergy between the main chain enzymes andα-L-Arabinofuranosidase was observed in the degradation of Alkali-extractable INSP(P＜0.05),the same asβ-galactosidase(P＜0.05),however,there is no synergy between the main chain enzymes and acetyl xylan esterase(P＞0.05),synergic effects between the main chain enzymes andα-L-Arabinofuranosidase is better thanβ-galactosidase(P＜0.05).Experiment 3.Adopting the experimental design by uniform distribution methods to determine the best proportion of enzyme in the degradation of Alkali-extractable INSP, The results showed that best proportion of cellulase,xylanase,pectinase,β-galactosidase arabinofurano- sidase was:10:9:8:6:4.Experiment 4.A scheme of single factor test was used in this experiment.16 major cocks were randomly divided into 4 groups each with 4 replications to study effects of suppliment amount of main-chain enzymes,branched-chain enzymes and phytase on digestibility and retention of nutrientions of rice bran.treatmentⅠwas rice bran,treatmentⅡsuppled with main-chain enzymes,treatmentⅢsuppled with main-chain enzymes and branched-chain enzymes,treatmentⅣsuppled with main-chain enzymes and phytase.The results showed that:Dry matter digestion,acid detergent fiber digestion,neutral detergent fiber digestion, energy retention for treatmentⅡ,Ⅲ,Ⅳwas higher than treatⅠ,But there were no significant influence among treatmentⅡ,Ⅲ,Ⅳ;Nitrogen retention for treatmentⅠ,Ⅱ,Ⅲwas higher than treatmentⅣ,But there were no significant influence among treatmentⅠ,ⅡandⅢ.