Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China; Beijing Laboratory for Food Quality and Safety, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; School of Food Science and Engineering, Hainan University, Haikou, China.
Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China; Beijing Laboratory for Food Quality and Safety, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
Food Res Int. 2024 Sep;191:114698. doi: 10.1016/j.foodres.2024.114698. Epub 2024 Jun 28.
Environmental microorganisms commonly inhabit dense multispecies biofilms, fostering mutualistic relationships and co-evolution. However, the mechanisms underlying biofilm formation and microbial interactions within the Baijiu fermentation microecosystem remain poorly understood. Hence, the objective of this study was to investigate the composition, structure, and interactions of microorganisms residing in biofilms on environmental surfaces in Baijiu production. The results revealed a shift in the bacteria-fungi interaction network following fermentation, transitioning from a cooperative/symbiotic relationship to a competitive/antagonistic dynamic. Core microbiota within the biofilms comprised lactic acid bacteria (LAB), yeast, and filamentous fungi. From the environmental surface samples, we isolated two strains of LAB (Lactiplantibacillus pentosus EB27 and Pediococcus pentosaceus EB35) and one strain of yeast (Pichia kudriavzevii EF8), all displaying remarkable biofilm formation and fermentation potential. Co-culturing LAB and yeast demonstrated a superior capacity for dual-species biofilm formation compared to mono-species biofilms. The dual-species biofilm displayed a two-layer structure, with LAB in the lower layer and serving as the foundation for the yeast community in the upper layer. The upper layer exhibited a dense distribution of yeast, enhancing aerobic respiration. Metabolic activities in the dual-species biofilm, such as ABC transporter, oxidative phosphorylation, citric acid cycle, sulfur metabolism, glycine, serine, threonine metabolism, lysine degradation, and cysteine and methionine metabolism, showed significant alterations compared to LAB mono-species biofilms. Moreover, bacterial chemotaxis, starch, and sucrose metabolism in the dual-species biofilm exhibited distinct patterns from those observed in the yeast mono-species biofilm. This study demonstrated that a core microbiota with fermentation potential may exist in the form of a biofilm on the surface of a Baijiu brewing environment. These findings provide a novel strategy for employing synthetic stable microbiotas in the intelligent brewing of Baijiu.
环境微生物通常栖息在密集的多物种生物膜中，促进共生关系和共同进化。然而，白酒发酵微生态系统中生物膜形成和微生物相互作用的机制仍知之甚少。因此，本研究旨在研究白酒生产中环境表面生物膜中微生物的组成、结构和相互作用。结果表明，发酵后细菌-真菌相互作用网络发生转变，从合作/共生关系转变为竞争/拮抗动态。生物膜中的核心微生物群由乳酸菌（LAB）、酵母和丝状真菌组成。从环境表面样品中，我们分离出两种 LAB 菌株（戊糖片球菌 EB27 和戊糖乳杆菌 EB35）和一种酵母菌株（毕赤酵母 EF8），它们都显示出显著的生物膜形成和发酵潜力。LAB 和酵母的共培养显示出比单培养更高的双物种生物膜形成能力。双物种生物膜呈现双层结构，下层为 LAB，上层为酵母群落的基础。上层酵母密集分布，增强有氧呼吸。与 LAB 单物种生物膜相比，双物种生物膜中的代谢活性，如 ABC 转运体、氧化磷酸化、柠檬酸循环、硫代谢、甘氨酸、丝氨酸、苏氨酸代谢、赖氨酸降解以及半胱氨酸和蛋氨酸代谢，都发生了显著变化。此外，双物种生物膜中的细菌趋化性、淀粉和蔗糖代谢与酵母单物种生物膜中的模式明显不同。本研究表明，具有发酵潜力的核心微生物群可能以生物膜的形式存在于白酒酿造环境的表面。这些发现为在白酒智能酿造中采用合成稳定微生物组提供了一种新策略。
