Phylogenetic Diversity and Anti-aging Activity of Bacteria Isolated from Two Mangrove Tree Habitats of the Beibu Gulf.

Mangroves are unique ecosystems that exist at the transition from land to oceans, harbor diverse bacterial communities and represent an important natural secondary metabolite resource that can be used to find and study diverse bioactive substances. However, the diversity and activities of cultivable bacteria associated with true mangrove trees remain poorly understood, especially within such habitats of the Beibu Gulf. In this study, we investigated the diversity of cultivable bacteria from Avicennia marina and Sonneratia apetala mangrove tree habitats within the Beibu Gulf to explore anti-aging activity of bacterial secondary metabolites. The recovered bacterial isolates belonged to 3 phyla, 25 families, 32 genera, and 40 species. Among these isolates, eight bacterial strains can significantly prolong the lifespan of the Caenorhabditis elegans N2 strain, and fourteen bacterial strains represent potentially new species within the genera Paracoccus, Sphingomonas, Teredinibacter, Novosphingobium, Pseudohoeflea, Acuticoccus, Actinotalea, Agromyces, Janibacter, Nocardia, Pseudokineococcus, Quadrisphaera, Demequina, and Rossellomorea. Of the newly identified strains, Actinotalea sp. (GXIMD7865) and Janibacter sp. (GXIMD7641) were isolated from S. apetala, they produced secondary metabolites with significant anti-aging activity, as it was shown in an experimental model with the use of Caenorhabditis elegans. These results demonstrate that mangrove ecosystems may have a high potential for synthesizing secondary metabolites with anti-aging activity from native bacterial populations. [ABSTRACT FROM AUTHOR]