摘要
试验旨在筛选出具有高效降解纤维素能力的菌株,降解玉米干酒糟及其可溶物(DDGS)的粗纤维,为玉米DDGS高效利用提供优质菌株。试验采用平板分离法从农家蜂蜜中分离1株具有降解纤维素能力的菌株Q_(1) ,通过形态学观察和16S rDNA序列分析并鉴定Q_(1) 为贝莱斯芽孢杆菌。以玉米DDGS为原材料,以纤维素降解率为指标,通过单因素试验考察了接菌量、液料比、发酵时间对粗纤维降解率的影响,在单因素的基础上,采用响应面法对各因素进行优化。结果显示:最佳发酵条件为接菌量4.8%、液料比0.5 mL/g、发酵时间75 h,发酵后的粗纤维降解率为28.31%,且发酵玉米DDGS中的粗蛋白、粗灰分含量显著高于发酵前(P<0.05),粗纤维含量显著低于发酵前(P<0.05)。研究表明,菌株Q_(1) 具有良好的纤维素降解能力,可提高玉米DDGS中粗纤维的降解率,为加大玉米DDGS在饲料中的使用量提供参考。
The experiment aims to screen for strains with efficient cellulose-degrading capabilities to degrade the crude fiber content of dried distillers'grains with solubles(DDGS),providing high-quality strains for the efficient resource utilization of corn DDGS.The experiment used the plate separation method to isolate a strain Q_(1) with cellulose-degrading ability from rural honey,and identified Q_(1) as Bacillus velezensis through morphological observation and 16S rDNA sequence analysis.Using corn DDGS as the raw material and the cellulose degradation rate as the index,the experiment investigated the effects of inoculum amount,liquid-to-solid ratio,and fermentation time on the crude fiber degradation rate through single-factor experiments.On the basis of single-factor experiments,the response surface method was used to optimize each factor.The results showed that the optimal fermentation conditions were an inoculum amount of 4.8%,a liquid-to-solid ratio of 0.5 mL/g,and a fermentation time of 75 hours,with a crude fiber degradation rate of 28.31%after fermentation.Moreover,the crude protein and ash content in the fermented corn DDGS were significantly higher than before fermentation(P<0.05),and the crude fiber content was significantly lower than before fermentation(P<0.05).The study indicates that strain Q_(1) has good cellulose-degrading capabilities and can improve the degradation rate of crude fiber in corn DDGS,providing a reference for increasing the use of corn DDGS in feed.
作者
彭雨晴
郭湧櫆
刘鹏宇
张勇
PENG Yu-qing;GUO Yong-kui;LIU Peng-yu;ZHANG Yong
出处
《饲料研究》
CAS
北大核心
2024年第14期67-74,共8页
Feed Research
基金
河南省高校大学生创新创业训练计划项目(项目编号:202210463034)
河南省科技攻关项目(项目编号:222102110446)。
