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The utilization of amine-negative starter based on an understanding of nitrogen metabolism is a useful method for controlling biogenic amine (BA) in Chinese rice wine (CRW) fermentation. The contribution of brewing materials to protein degradation was analyzed; wheat Qu protein had no effect, and yeast autolysis generated 10% amino nitrogen. Milling degree of rice was strongly correlated with BAs formation ( R = 0.99). Subsequently, Lactobacillus plantarum and Staphylococcus xylosus were coinoculated as amine-negative starter at an optimized ratio of 1:2. Coinoculation induced a significant reduction in total BAs (43.7%, 44.5 mg L), putrescine (43.0%, 20.4 mg L), tyramine (42.8%, 14.3 mg L), and histamine (42.6%, 3.5 mg L) content. Notably, BAs degradation ability of Staphylococcus xylosus was stronger than the suppression effect of Lactobacillus plantarum, and higher lactic acid bacteria (LAB) amount has a positive correlation with lower BAs content. Overall, mixed strains exerted a synergistic effect in lowering BAs accumulation via decarboxylation and transamination.

The exogenous functional microorganisms to regulate the biogenic amines (BAs) content is a common approach in fermentation systems. Here, to better understand the microbial traits of succession trajectories in resource-based and biotic interference system, the BAs-related primary and secondary succession were tracked during industrial semidry Chinese rice wine (CRW) fermentation. Dominant abundance and BAs-associated microbial functionality based on PICRUSt indicated that Citrobacter, Acinetobacter, Lactobacillus, Exiguobacterium, Bacillus, Pseudomonas and Enterobacter were prominently contributed to decarboxylase gene family in CRW. The expression level of tyrosine decarboxylase (tyrDC), ornithine decarboxylase (odc) and agmatine deiminase gene (aguA) were assessed by q-PCR. The transcription levels of these genes are unmatched with BAs formation rate during post fermentation, indicating that acidification and carbon source depletion upregulated the expression and microbes launch the dormancy strategy to respond to unfavorable conditions. Furthermore, microbial interference of CRW fermentation by co-inoculated Lactobacillus plantarum (ACBC271) and Staphylococcus xylosus (CGMCC1.8382) at a ratio of 1:2 exhibited the best synergetic control of BAs. Spearman correlations revealed that Lactobacillus and Staphylococcus exhibited influence on BAs-associated microbiota (|ρ|>0), Exiguobacterium and Pseudomonas were strongly suppress by Lactobacillus (P < 0.05, ρ = -0.867, ρ = -0.782), Staphylococcus showed the strongest inhibitory effect toward Lactobacillus (ρ = -0.115) and Citrobacter (ρ = -0.188) in co-inoculated 1:2 group. The high inhibitory effect of exogenous added strains on specific bacteria presented the evidence for the obtained BAs-associated contributors. Overall, this work provides important insight into the microbial traits rely on resource usage and functional microbiota within food microbial ecology. Importance Understanding the shifting patterns of substance usage and microbial interactions is a fundamental objective within microbiology and ecology. Analyses of primary and secondary microbial succession allows for determinations of taxonomic diversity, community traits and functional transformations over time or after a disturbance. The kinetics of BA generation, the patterns of resource consumption, functional metagenome prediction and microbial interactions were profiled to elucidate the equilibrium mechanism of microbial systems. Secondary succession after a disturbance triggers a change in resource usage, which in turn affects primary succession and metabolism. In the study, the functional potential of exogenous microorganisms under disturbance synergized with secondary succession strategies, including rebalancing and dormancy, which ultimately lowered BA accumulation. Thus, this succession system could facilitate to settle essential issues with respect to microbial traits rely on resource usage and microbial interactions that occur in natural ecosystems.

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