Comparative Analysis of Bacterial Community Structures and Functions in Chaste Honey Produced by Sympatric Apis cerana and Apis mellifera

To clarify how bee species shape the taxonomic structure and functional potential of honey bacterial communities, this study employed 16S rRNA high-throughput sequencing to analyze the diversity, composition, and predicted functions of the bacterial communities in mono-floral chaste honey produced by sympatric Apis cerana and Apis mellifera. The results demonstrated no significant differences in bacterial richness or diversity between the two types of honey, whereas their bacterial community structures were significantly distinct. Firmicutes and Proteobacteria were the dominant phyla in both types of honey. Saccharibacter was the core dominant genus, while the relative abundances of minor genera such as Propionibacterium and Oceanobacillus differed significantly between the two types of honey. Functional prediction using PICRUSt2 revealed that the core metabolic functional profiles of the bacterial communities in these types of honey were highly similar, both being enriched in carbohydrate degradation, amino acid biosynthesis, and fermentation pathways. These metabolic characteristics were highly compatible with the high-sugar, acidic, and microanaerobic matrix environment of honey. This study reveals that bee species are the key biotic factor driving the structural differentiation of honey bacterial communities, while the physicochemical properties of the honey matrix are the major environmental pressure shaping the convergence of their core metabolic functions. By systematically characterizing the bacterial community structures of mature chaste honey produced by A. cerana and A. mellifera, this study elucidates the bee-specific microbiota in honey, providing a theoretical basis for honey traceability, quality assessment, and the exploitation of functional microbial resources.