Synergistic effects of cellulase and lactic acid bacteria(Pediococcus pentosaceus and Levilactobacillus brevis) on alfalfa silage fermentation and microbial dynamics

Abstract This study evaluated the effects of Lactic acid bacteria and cellulase, individually and in combination, on fermentation quality and microbial community dynamics of alfalfa silage. Six treatments were tested, including control, cellulase alone and two lactic acid bacteria species (Pediococcus pentosaceus, Levilactobacillus brevis) applied individually or in combination with cellulase. The results showed that Levilactobacillus brevis in combination with cellulase, producing higher lactic acid concentrations, lower pH (< 4.2) to the other treatments. The microbiome analysis revealed that Lactiplantibacillus was dominant, while undesirable bacterium Achromobacter was suppressed. Functional prediction of microbial communities analysis indicated a higher predicted abundance of sequences associated with pyruvate metabolism, glycolysis/gluconeogenesis and starch and sucrose metabolism pathways. These findings provide insights into optimizing alfalfa silage quality through synergistic use of cellulase and lactic acid bacteria silage inoculants with high metabolic stability. Graphical Abstract