Microbial Diversity and Functions of Acacia Honey Revealed by Environmental DNA Metabarcoding for Geographic Origin Identification

This study analyzed fifteen domestic and four imported Robinia honey samples using V3- V4 16S rRNA gene metabarcoding, identifying a total of 1,147 bacterial taxa. The 39 most prevalent taxa were grouped into five functional categories based on their physiological and ecological characteristics: (1) honeybee-associated symbionts, such as Apilactobacillus spp. and Gilliamella apicola, which aid in digestion and immune function; (2) pathogenic bacteria, including Melissococcus plutonius and Paenibacillus larvae, responsible for foulbrood diseases; (3) beneficial and probiotic strains like Bacillus atrophaeus, Latilactobacillus sakei, and Clostridium butyricum with fermentative and antimicrobial properties; (4) skin and human commensals, such as Cutibacterium acnes and Staphylococcus capitis, suggestive of potential operator or cross-contamination; and (5) environmental and plant-associated microorganisms, including Pantoea, Acinetobacter, Pseudomonas, and Erwinia, originating from soil, vegetation, and air. These microbial community profiles show potential as biomarkers for verifying honey origin, as well as providing simultaneous insights into apiary health and disease risks.