Li Junfeng, Wang Siran, Zhao Jie, Dong Zhihao, Liu Qinhua, Dong Dong, Shao Tao
Institute of Ensiling and Processing of Grass, College of Agro-Grassland Science, Nanjing Agricultural University, Nanjing, China.
J Appl Microbiol. 2022 Apr;132(4):2572-2582. doi: 10.1111/jam.15388. Epub 2021 Dec 26.
To enrich lignocellulolytic microbial consortia and evaluate whether a combination of these consortia and Lactobacillus plantarum can facilitate degradation of structural carbohydrates and improve fermentation quality of high-moisture alfalfa silage.
Two novel microbial consortia (CL and YL) with high lignocellulolytic potential were enriched, and had higher enzyme activities at slightly acidic conditions (pH 3.5-6.5). Two consortia were inoculated with and without combined L. plantarum (LP) to alfalfa for up to 120 days of ensiling. The two consortia alone or combined with LP significantly (p < 0.05) increased lactic-to-acetic acid ratios and decreased contents of volatile organic acids and NH -N as compared to the control. Treatments that combining microbial consortia and LP further resulted in the higher contents of lactic acid (LA), water soluble carbohydrates (WSC) and crude protein, dry matter (DM) recovery, and lower neutral detergent fibre, acid detergent lignin and cellulose contents, with YLP silage showing the lowest pH (4.41) and highest LA content (76.72 g kg DM) and the conversion of WSC into LA (184.03%).
The addition of lignocellulolytic microbial consortia (CL or YL) to alfalfa silages as attractive silage inoculants could improve fermentation quality, and that their combination with L. plantarum appeared more effective on the degradation of structural carbohydrates and conversion of soluble carbohydrates into LA.
High-moisture alfalfa is difficult to ensile due to its high buffering capacity and low readily fermentable carbohydrate contents. Microbial consortia (CL and YL) can encode a broad selection of multi-functional CAZymes, and their combination with LP could be promising for the degradation of structural carbohydrates simultaneously with improvement fermentation quality, with high performance in LA production.
富集木质纤维素分解微生物群落，并评估这些群落与植物乳杆菌的组合是否能促进结构性碳水化合物的降解，提高高水分苜蓿青贮饲料的发酵品质。
富集了两种具有高木质纤维素分解潜力的新型微生物群落（CL和YL），它们在微酸性条件（pH 3.5 - 6.5）下具有较高的酶活性。在有或没有联合植物乳杆菌（LP）的情况下，将这两种群落接种到苜蓿上进行长达120天的青贮。与对照相比，单独的两种群落或与LP联合使用均显著（p < 0.05）提高了乳酸与乙酸的比例，降低了挥发性有机酸和NH₃ - N的含量。微生物群落与LP联合处理进一步导致乳酸（LA）、水溶性碳水化合物（WSC）和粗蛋白含量更高，干物质（DM）回收率更高，中性洗涤纤维、酸性洗涤木质素和纤维素含量更低，其中YLP青贮饲料的pH最低（4.41），LA含量最高（76.72 g kg⁻¹ DM），WSC转化为LA的比例最高（184.03%）。
向苜蓿青贮饲料中添加木质纤维素分解微生物群落（CL或YL）作为有吸引力的青贮接种剂可以改善发酵品质，并且它们与植物乳杆菌的组合在结构性碳水化合物的降解以及可溶性碳水化合物转化为LA方面似乎更有效。
高水分苜蓿由于其高缓冲能力和低易发酵碳水化合物含量而难以青贮。微生物群落（CL和YL）可以编码多种多功能碳水化合物活性酶，它们与LP的组合有望在降解结构性碳水化合物的同时提高发酵品质，并在LA生产方面具有高性能。
