Xu Dongmei, Ding Wurong, Ke Wencan, Li Fuhou, Zhang Ping, Guo Xusheng
State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China.
Probiotics and Biological Feed Research Center, Lanzhou University, Lanzhou, China.
Front Microbiol. 2019 Jan 23;9:3299. doi: 10.3389/fmicb.2018.03299. eCollection 2018.
The present study investigated the species level based microbial community and metabolome in corn silage inoculated with or without homofermentative and heterofermentative using the PacBio SMRT Sequencing and time-of-flight mass spectrometry (GC-TOF/MS). Chopped whole crop corn was treated with (1) deionized water (control), (2) , or (3) . The chopped whole crop corn was ensiled in vacuum-sealed polyethylene bags containing 300 g of fresh forge for 90 days, with three replicates for each treatment. The results showed that a total of 979 substances were detected, and 316 different metabolites were identified. Some metabolites with antimicrobial activity were detected in whole crop corn silage, such as catechol, 3-phenyllactic acid, 4-hydroxybenzoic acid, azelaic acid, 3,4-dihydroxybenzoic acid and 4-hydroxycinnamic acid. Catechol, pyrogallol and ferulic acid with antioxidant property, 4-hydroxybutyrate with nervine activity, and linoleic acid with cholesterol lowering effects, were detected in present study. In addition, a flavoring agent of myristic acid and a depression mitigation substance of phenylethylamine were also found in this study. Samples treated with inoculants presented more biofunctional metabolites of organic acids, amino acids and phenolic acids than untreated samples. The species covered over 98% after ensiling, and were mainly comprised by the and . As compared to the control silage, inoculation of increased the relative abundances of and , and a considerable decline in the proportion of was observed; whereas an obvious decrease in and increases in and were observed in the inoculated silage. Therefore, inoculation of and regulated the microbial composition and metabolome of the corn silage with different behaviors. The present results indicated that profiling of silage microbiome and metabolome might improve our current understanding of the biological process underlying silage formation.
本研究采用PacBio SMRT测序和飞行时间质谱（GC-TOF/MS）技术，调查了接种或未接种同型发酵菌和异型发酵菌的玉米青贮饲料中基于物种水平的微生物群落和代谢组。将切碎的全株玉米分别用（1）去离子水（对照）、（2）[此处原文缺失具体接种物名称]或（3）[此处原文缺失具体接种物名称]处理。将切碎的全株玉米装入含有300克新鲜饲料的真空密封聚乙烯袋中青贮90天，每个处理设置三个重复。结果表明，共检测到979种物质，鉴定出316种不同的代谢物。在全株玉米青贮饲料中检测到一些具有抗菌活性的代谢物，如儿茶酚、3-苯乳酸、4-羟基苯甲酸、壬二酸、3,4-二羟基苯甲酸和4-羟基肉桂酸。本研究还检测到具有抗氧化特性的儿茶酚、连苯三酚和阿魏酸，具有神经活性的4-羟基丁酸，以及具有降胆固醇作用的亚油酸。此外，本研究还发现了肉豆蔻酸调味剂和苯乙胺抗抑郁物质。接种处理的样品比未处理的样品呈现出更多的有机酸、氨基酸和酚酸等生物功能代谢物。青贮后[此处原文缺失具体微生物名称]物种覆盖超过98%，主要由[此处原文缺失具体微生物名称]和[此处原文缺失具体微生物名称]组成。与对照青贮饲料相比，接种[此处原文缺失具体接种物名称]增加了[此处原文缺失具体微生物名称]和[此处原文缺失具体微生物名称]的相对丰度，同时观察到[此处原文缺失具体微生物名称]比例显著下降；而在接种[此处原文缺失具体接种物名称]的青贮饲料中，观察到[此处原文缺失具体微生物名称]明显减少，[此处原文缺失具体微生物名称]和[此处原文缺失具体微生物名称]增加。因此，接种[此处原文缺失具体接种物名称]和[此处原文缺失具体接种物名称]以不同方式调节了玉米青贮饲料的微生物组成和代谢组。目前的结果表明，青贮饲料微生物组和代谢组分析可能会提高我们目前对青贮饲料形成背后生物学过程的理解。
