Characterization of the microbial communities inhabiting tropical propolis of Puerto Rico. Propolis microbiome (Puerto Rico)

Propolis is a resinous material produced by honeybees from different plants sources, used as a building material and to protect the hive from parasite and pathogens. Despite propolis antimicrobial activity, recent studies show that propolis hosts microbial strains with antimicrobial potential which could contribute to its properties. In this study we reported the first description of the bacterial community of propolis samples from two different areas of Puerto Rico (PR, USA) by both cultivation and targeted-metataxonomic, and an evaluation of the antimicrobial potential of the isolated bacteria and propolis extracts. We demonstrated that propolis hosts a rich bacterial community, with the presence of taxa already detected in other hive components and in the bee’s foraging environment. Isolated bacteria, as well as propolis extracts, showed a great antimicrobial potential against all of the tester strains, more efficiently against Gram-positive. Metataxonomic analysis showed an appreciable bacterial diversity in both areas and a statistically significant dissimilarity in the taxa composition of the two areas, probably due to the different climatic conditions. These results support the hypothesis that propolis microbiota could play a role in propolis properties, contributing to enhance its intrinsic antimicrobial activity.