不同成熟年限宣威火腿中的微生物演替、功能动态及潜在生物标记特征

Microbial Succession, Functional Dynamics, and Potential Biomarker Characteristics in Xuanwei Ham at Different Maturation Ages

摘要:

长期自然发酵过程中微生物群落的演替是决定传统风干火腿品质形成的关键因素。为阐明不同成熟年限宣威火腿的微生物结构变化及其潜在功能特征，本研究基于高通量测序技术，对宣威火腿在三个成熟等级（A、B、C）的细菌和真菌群落进行了系统分析。α多样性分析显示，细菌Chao1丰度在A、B、C三等级中分别为41.57、42.92和27.11；真菌Shannon指数分别为1.71、1.84和0.57，整体呈现B级>A级>C级的变化趋势，提示B级成熟样品具有最高的整体多样性。β多样性分析表明，不同成熟阶段样品在主坐标分析和非度量多维尺度分析中均形成清晰分组（置换多元方差分析，P<0.05），且群落结构沿成熟梯度呈现显著分化，A级成熟样品表现出更高的组内一致性。群落组成分析表明，葡萄球菌属（Staphylococcus）、四联球菌属（Tetragenococcus）、曲霉属（Aspergillus）和德巴利酵母属（Debaryomyces）在不同成熟阶段占据优势地位。基于线性判别分析效应量分析，不同成熟阶段呈现出特征性富集的微生物类群，这些分类单元可作为成熟阶段相关的潜在指示菌。功能预测结果显示，氨基酸、脂质和碳水化合物代谢相关通路在中后期样品中显著富集，反映了发酵过程中活跃的代谢转化。综上，本研究揭示了宣威火腿在不同成熟阶段的微生物演替规律及其潜在功能特征，为成熟阶段的区分和传统发酵火腿微生物资源的进一步挖掘提供了基础数据支持。

Abstract:

Microbial succession during long-term natural fermentation plays a critical role in the quality formation of traditional dry-cured hams. To elucidate microbial community shifts and their potential functional characteristics in Xuanwei ham at different maturity levels, high-throughput sequencing was employed to systematically investigate bacterial and fungal communities across three maturity grades (A, B, and C). Alpha diversity analysis showed that bacterial Chao1 richness values were 41.57, 42.92, and 27.11 for grades A, B, and C, respectively, while fungal Shannon indices were 1.71, 1.84, and 0.57, collectively exhibiting a trend of B > A > C, indicating that grade B samples harbored the highest overall microbial diversity. Beta diversity analyses based on principal coordinates analysis (PCoA) and non-metric multidimensional scaling (NMDS) revealed clear clustering of samples according to maturity stage (permutational multivariate analysis of variance, P < 0.05), with pronounced community differentiation along the maturation gradient. Notably, grade A samples exhibited higher within-group consistency in community structure. Taxonomic profiling demonstrated that Staphylococcus, Tetragenococcus, Aspergillus, and Debaryomyces predominated across different maturity stages. Linear discriminant analysis effect size (LEfSe) further identified stage-enriched microbial taxa, which may serve as potential indicators associated with specific maturation stages. Functional prediction suggested that pathways related to amino acid, lipid, and carbohydrate metabolism were significantly enriched in mid- to late-stage samples, reflecting active metabolic transformations during fermentation. In summary, this study elucidates microbial succession patterns and potential functional dynamics of Xuanwei ham across different maturity stages, providing foundational data for maturity stage discrimination and further exploration of microbial resources in traditional dry-cured ham fermentation.