Microbial Population Succession and Community Diversity and Its Correlation with Fermentation Quality in Soybean Meal Treated with Enterococcus faecalis during Fermentation and Aerobic Exposure

Abstract

This study assessed the effects of Enterococcus faecalis (E. faecalis) in combination with protease on fermentation characteristics and microbial communities during ensiling and aerobic exposure phases of soybean meal (SBM). In this study, response surface methodology (RSM) was used to optimize the optimal growth conditions of E. faecalis ZZUPF95, which produced protease, and fermented SBM under the optimal fermentation conditions. The fermentation test was divided into four groups as follows: CK (Control check), ZZUPF95, Protease and ZZUPF95+Protease groups. Results showed that the best medium ratio of ZZUPF95 was glucose 1%, peptone 2%, inorganic salt 1.47%; fermentation time 36 h, inoculation amount 10%, ratio of material to water 1:1 is the optimal fermentation scheme; after fermentation and aerobic exposure treatment, ZZUPF95 and ZZUPF95 + Protease group can reduce the pH of feed, improve the content of lactic acid in the fermentation system, and have the effect of inhibiting the reproduction of pathogenic bacteria, increasing the content of crude protein and ether extract, and degrading crude fiber; the microbial community of SBM were changed after fermentation and aerobic exposure. This study explored the changes of fermentation quality of SBM, which has certain theoretical value to improve the fermentation mode and storage of SBM.

Microbial community and fermentation characteristic of whole-crop wheat silage treated by lactic acid bacteria and Artemisia argyi during ensiling and aerobic exposure

“…Contents of acetic acid in all AA-treated groups were significantly higher after ensiling 60 days. For appropriate acetic acid concentration that could inhibit yeast and improve aerobic stability, AA groups could significantly inhibit fungi and improve aerobic stability of silage, which were also consistent with the findings of Ma et al (2022) and Wang et al (2022b).…”

“…Pantoea represents the most dominant genera in fresh materials ( Ma et al, 2022 ), and the WCWD in this study was no exception. However, the relative abundance of Pantoea decreased during the ensiling and the following aerobic exposure, while it was higher at 20% AA, this is consistent with Wang et al (2021) .…”

Investigation on Fermentation Characteristics and Microbial Communities of Wheat Straw Silage with Different Proportion Artemisia argyi

“…Firmicutes is the dominant phylum in the fermentation of silage. It is an important acid-hydrolytic microorganism in anaerobic environments [ 57 , 58 ], probably because anaerobic and acidic environments benefit the growth of Firmicutes during fermentation [ 59 ]. Meanwhile, the 60% AA group had a richer Firmicutes community than other groups from the beginning (72.56%) to the end of aerobic exposure (86.44%).…”

Variation of Microbial Community and Fermentation Quality in Corn Silage Treated with Lactic Acid Bacteria and Artemisia argyi during Aerobic Exposure

“…This observation indicated that ZA3 and AA can change fungi community when environment changes from anaerobic to aerobic. It is possible that acid-tolerant bacteria still dominate the bacterial community in the early period of aerobic exposure, and the variation of microbial community might explain the difference in fermentation quality [ 15 , 38 , 39 ].…”

“…The majority of bacteria involved in lactic acid fermentation belong to the Firmicutes. However, once the WCCS silage was exposed to oxygen, Firmicutes were gradually replaced by Proteobacteria, which might be because an increase in pH and decrease in organic acids are not beneficial to the proliferation of Firmicutes [ 15 , 39 ].…”