副干酪乳杆菌对青贮苜蓿有氧暴露品质和细菌多样性的影响  

Effects of Lactobacillus paracasei on the Quality and Bacterial Diversity of Silage Alfalfa After Aerobic Exposure

作　　者：王琦 武之绚 陈钟玲 吴白乙拉 胡宗福[1] 牛化欣[1] WANG Qi;WU Zhi-xuan;CHEN Zhong-ling;WU Bai-yi-la;HU Zong-fu;NIU Hua-xin(College of Animal Science and Technology,Inner Mongolia University for Nationalities,Tongliao 028000)

机构地区：[1]内蒙古民族大学动物科技学院,通辽028000

出　　处：《生物技术通报》2021年第9期77-85,共9页Biotechnology Bulletin

基　　金：内蒙古自治区关键技术攻关项目(2020GG0108);内蒙古自治区“草原英才工程”青年创新创业人才第一层次培养项目(Q2017022);内蒙古自治区自然基金面上项目(2018MS03022)。

摘　　要：采用16S rRNA高通量测序技术,检测青贮苜蓿有氧暴露细菌群落动态变化,旨在为青贮苜蓿有氧暴露细菌多样性变化及其接种乳酸菌防止有氧变质提供依据。将未接种(CON)和接种副干酪乳杆菌(LCP)的苜蓿青贮发酵56 d,分析有氧暴露后0 d、7 d、14 d青贮发酵品质和细菌多样性的动态变化。结果表明,有氧暴露使未接种青贮苜蓿pH上升,乳酸含量下降。相比CON,接种副干酪乳杆菌在有氧暴露期间pH升高幅度更小,乳酸含量更高(P<0.05)。CON主要有乳杆菌属、肠杆菌属和肠球菌属为主,其中肠杆菌属和肠球菌属丰度逐渐下降;LCP主要以乳杆菌属为主,其丰度逐渐下降。此外,有氧暴露14 d时,LCP降低了醋杆菌属的丰度。关联性分析发现,乳杆菌属与pH呈负相关(P<0.05),肠杆菌属、肠球菌属、魏氏菌属、Cedecea、Sporolactobacillus与pH呈正相关(P<0.05),醋杆菌属Acetobacter与乳酸和乙酸负相关(P<0.05)。综上,本研究发现醋杆菌属在长期有氧暴露的青贮苜蓿中大量存在,降低了乳酸和乙酸的含量。接种副干酪乳杆菌可提高有氧暴露青贮苜蓿乳杆菌属的丰度,降低长期(14 d)有氧暴露醋杆菌属的丰度。因此青贮苜蓿接种副干酪乳杆菌可改善短期有氧暴露青贮品质,提高其有氧稳定性,减缓有氧变质。16S rRNA high-throughput sequencing technology was used to detect the dynamic variations of bacterial community in the silage alfalfa after aerobic exposure,aiming to provide a basis for the dynamic changes of bacterial diversity in the aerobic exposure of silage alfalfa and the inoculation of lactic acid bacteria to prevent aerobic deterioration.Alfalfa silage without inoculation(CON)and inoculated with Lactobacillus paracasei(LCP)were fermented for 56 d,and the dynamic changes of fermentation quality and bacterial diversity of the silage at 0,7,and 14 d after aerobic exposure.The results showed that aerobic exposure resulted in the increase of the pH of uninoculated silage alfalfa and the decrease of the lactic acid content.Compared with CON,inoculation of L.paracasei had a smaller increase in pH but higher lactic acid content during aerobic exposure(P<0.05).CON was mainly composed of Lactobacillus,Enterobacter,and Enterococcus,among which the abundance of Enterobacter and Enterococcus gradually decreased;the LCP group was mainly dominated by Lactobacillus,and its abundance gradually decreased.In addition,abundance of Acetobacter appeared after 14 d of aerobic exposure.Correlation analysis revealed that Lactobacillus was negatively correlated with pH(P<0.05).Enterobacter,Enterococcus,Wierella,Cedecea,Sporolactobacillus were positively correlated with pH.Acetobacter was negatively correlated with lactic acid and acetic acid(P<0.05).In summary,this study found that Acetobacter was abundant in the silage alfalfa exposed to long-term aerobic exposure,reducing the content of lactic acid and acetic acid.Inoculation of L.paracasei may increase the abundance of Lactobacillus and reduce the abundance of Acetobacter in long-term(14 d)aerobic exposure.Therefore,inoculation of silage alfalfa with L.paracasei can improve the quality of short-term aerobic exposure silage,enhance its aerobic stability,and slow down aerobic deterioration.

关 键 词：青贮苜蓿 有氧暴露 副干酪乳杆菌 细菌多样性 

分 类 号：S816.53[农业科学—饲料科学]