外源非淀粉多糖酶复合配比优化及其对体外发酵特性的影响  

Optimization of Exogenous Complex Non-Starch Polysaccharidases Ratio and Their Effect on in Vitro Fermentation Characteristics

作　　者：薛玉洋 孙浩彬 王银玲 李佳橙 刘保仓[1,2] 韩坤 齐亚银[1] 陈程 张文举[1] XUE Yuyang;SUN Haobin;WANG Yinling;LI Jiacheng;LIU Baocang;HAN Kun;QI Yayin;CHEN Cheng;ZHANG Wenju(College of Animal Science and Technology,Shihezi University,Shihezi 832003,China;Xinjiang Taikun Group Changji Feed Limited Liability Company,Changji 831199,China)

机构地区：[1]石河子大学动物科技学院,石河子832003 [2]新疆泰昆集团昌吉饲料有限责任公司,昌吉831199

出　　处：《动物营养学报》2022年第11期7431-7442,共12页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：国家自然科学基金项目(32060770);石河子大学高层次人才科研启动项目(RCZK201901);石河子大学青年拔尖人才培育计划(KX01500301);天山创新团队计划(2021D14008)。

摘　　要：本试验旨在研究外源非淀粉多糖酶的最适配比及其对体外发酵参数的影响。通过反刍动物瘤胃体外发酵模型进行体外消化试验,采用单因素完全随机试验设计,在断奶育肥羔羊饲粮中分别添加7种不同水平的4种酶(纤维素酶、木聚糖酶、β-葡聚糖酶、甘露聚糖酶),每个水平设3个重复。以产气量(GP)及干物质降解率(DMD)为评价指标,确定单酶的最佳添加量;在此基础上,利用正交设计4因子3水平L_(9)(3~4)试验,对4种酶进行复配组合,确定最适配比;以在基础饲粮中添加最适配比外源复合非淀粉多糖酶的试验饲粮(试验组)与基础饲粮(对照组)进行体外发酵对比,分别测定在不同发酵时间(2、4、6、8、12、24、48 h)的GP、DMD及发酵参数。结果表明:以断奶育肥羔羊饲粮为底物优选出4种酶,最佳添加量为纤维素酶750 U/g、木聚糖酶125 U/g、β-葡聚糖酶750 U/g、甘露聚糖酶125 U/g;由此催化反应的GP和DMD最适配比为纤维素酶∶木聚糖酶∶β-葡聚糖酶∶甘露聚糖酶=1 000∶250∶500∶50(U/g,干物质基础);最适配比外源复合非淀粉多糖酶在瘤胃体外发酵中的应用结果显示,培养48 h后,各组发酵液pH均处于正常水平;试验组平均GP、DMD、氨态氮(NH_(3)-N)浓度极显著高于对照组(P<0.01);试验组平均微生物蛋白(MCP)浓度低于对照组,但差异不显著(P>0.05);试验组与对照组的丙酸、丁酸、总挥发性脂肪酸(TVFA)浓度与乙丙比(A/P)差异极显著(P<0.01)。由此可见,添加适宜配比[纤维素酶∶木聚糖酶∶β-葡聚糖酶∶甘露聚糖酶=1 000∶250∶500∶50(U/g,干物质基础)]的外源复合非淀粉多糖酶可增加体外发酵GP、DMD,改善瘤胃发酵,具有促进饲粮中营养物质消化的潜力。The aim of this experiment was to investigate the optimal ratio of exogenous complex non-amylose polysaccharidases and their effect on in vitro fermentation characteristics.A single-factor completely randomized experimental design was used in this experiment,in which four single enzymes(cellulase,xylanase,β-glucanase and mannanase)were added to the diet of weaned fattening lambs at seven levels,with three replicates for each level.The optimal addition of the single enzymes was determined using gas production(GP)and dry matter degradation rate(DMD)as evaluation indexes.Based on the above results,the four enzymes were combined in a compound combination using an orthogonal design 4 factors and 3 levels L_(9)(3~4)test to determine the optimal ratio.The in vitro fermentation was carried out by adding the exogenous complex non-amylose polysaccharidases with optimal ratio to a basal diet(test group)compared with the basal diet(control group),and the GP,DMD and fermentation parameters were determined at different fermentation time(2,4,6,8,12,24,48 h).The results showed that the optimal addition of the four single enzymes used the diet of weaned fattening lambs as substrate were 750 U/g for cellulase,125 U/g for xylanase,750 U/g for β-glucanase and125 U/g for mannanase,and the optimal ratio of GP and DMD for the reaction catalyzed by this complex enzymes were cellulase ∶xylanase ∶β-glucanase ∶mannanase = 1 000∶250∶500∶50(U/g,dry matter basis).The application results of the exogenous complex non-amylose polysaccharidases with optimal ratio in the rumen in vitro fermentation showed that,after 48 h of incubation,the pH of the fermentation broth was at a normal level in all groups;the average GP,DMD and NH_(3)-N concentration of the test group was extremely significantly higher than those of the control group(P<0.05);the microbial protein(MCP)concentration of the test group was lower than that of the control group,but the difference was not significant(P>0.05). The differences in propionic acid,butyric acid,tot

关 键 词：非淀粉多糖酶 体外发酵 产气量 干物质降解率 酶谱 

分 类 号：S816.7[农业科学—饲料科学]