乳酸杆菌的分离鉴定及其对皇竹草青贮饲料发酵品质的影响  

Isolation and Identification of Lactobacillus and Their Effects on Fermentation Quality of Pennisetum sinense Silage

作　　者：谢婷霞 曹雪笛 谭玉兰 李果 晋蕾 刘书亮[2] 敖晓琳[2] 赵珂 邹立扣 XIE Tingxia;CAO Xuedi;TAN Yulan;LI Guo;JIN Lei;LIU Shuliang;AO Xiaolin;ZHAO Ke;ZOU Likou(College of Resources,Sichuan Agricultural University,Chengdu 611130,China;College of Food Science,Sichuan Agricultural University,Ya’an 615014,China)

机构地区：[1]四川农业大学资源学院,成都611130 [2]四川农业大学食品学院,雅安615014

出　　处：《动物营养学报》2022年第6期4060-4070,共11页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：四川省科技计划项目(2021ZDZX0012);四川省科技厅项目(2020ZYD003)。

摘　　要：本试验旨在探讨将从黑麦草青贮饲料中分离获得的乳酸杆菌添加到皇竹草青贮中对其发酵品质及微生物多样性的影响。采用传统可培养法分离乳酸杆菌,通过形态学鉴定和16S rRNA测序比对后保存备用。在切碎的皇竹草样品中分别添加分离的植物乳杆菌LAB158(Lactobacillus plantarum LAB158)、玉米乳杆菌MZN1 (Lactobacillus zeae MZN1)和草本乳杆菌P-1-12(Lactobacillus herbaceous P-1-12)作为试验组,同时添加等量无菌水作为对照组,打包后经60 d青贮发酵,对青贮样品进行感官评定,并分析其营养成分含量和微生物群落结构。结果表明:与对照组相比,3个试验组青贮饲料的色泽评分和pH评分均显著提高(P<0.05),干物质、粗蛋白质、粗脂肪和乳酸等营养成分含量也显著提高(P<0.05),同时LAB158组甘氨酸和丙氨酸等鲜味氨基酸含量也显著提高(P<0.05)。基于高通量测序发现,各组青贮饲料中优势菌在门水平上均是厚壁菌门,且相对丰度以对照组最低;其次为变形菌门,且相对丰度以对照组最高。各组优势菌在属水平上均为乳杆菌属,另外还有鞘氨醇杆菌属和魏斯氏菌属等。由此可见,添加乳酸杆菌能够改善青贮饲料的发酵品质,提高其营养品质,Alpha多样性分析发现添加植物乳杆菌LAB158和玉米乳杆菌MZN1后,微生物丰富度和多样性均得到提高,综合判定添加植物乳杆菌LAB158菌株的青贮效果更好。This experiment was conducted to investigate the effects of Lactobacillus isolated from ryegrass silage on fermentation quality and microbial diversity of Pennisetum sinese silage. Lactobacillus was isolated by traditional culture method,and then preserved for use after morphological identification and 16S rRNA sequencing comparison. The isolated Lactobacillus plantarum LAB158,Lactobacillus zeae MZN1 and Lactobacillus herbaceous P-1-12 were added into the mince samples of Pennisetum sinese as experimental groups,respectively,and the control group was added with the same amount of sterile water. The silage samples were fermented for 60 days after packaging,and the sensory evaluation,nutrient contents and microbial community structure were measured. The results showed that compared with the control group,the color score and pH score of silage in 3 experimental groups were significantly increased(P<0.05),and the contents of dry matter,crude protein,ether extract and lactic acid were also significantly increased(P<0.05),while the contents of umami amino acids such as glycine and alanine in LAB158 group were also significantly increased(P<0.05). Based on high-throughput sequencing,it was found that the dominant bacteria in each group were Firmicutes at phylum level,and the relative abundance was the lowest in the control group;Proteobacteria followed,and the relative abundance was the highest in the control group. At the genus level,the dominant bacteria in each group were Lactobacillus,Sphingobacterium and Weissella,etc. Thus it can be seen that Lactobacillus can improve the fermentation quality and nutritional quality of silage. Alpha diversity analysis shows that adding Lactobacillus plantarum LAB158 and Lactobacillus zeae MZN1 can increase the richness and diversity of microbial community. It is comprehensively determined that Lactobacillus plantarum LAB158 strain has better silage effect.

关 键 词：皇竹草 青贮 乳酸杆菌 发酵品质 微生物多样性 

分 类 号：S816[农业科学—饲料科学]