The present study focuses on the distribution of cultivable heterotrophic bacteria and their extracellular enzyme production. The study was conducted during 2018 at three sampling stations of Ayiramthengu mangrove ecosystem. The bacteria were isolated from two distinct regions such as upper and lower pneumatophore surface from each sampling sites. The different bacterial genera isolated were Pseudomonas sp., Acinetobacter sp., Moraxella sp., Streptoccoccus sp., Deinococcus sp., Micrococcus sp., Paenibacillus sp. and Staphylococcus sp., of which Pseudomonas sp. was the dominant one. Mean bacterial population in upper region of pneumatophores was less than the lower region in all the studied sites. Additionally, there was a significant difference (p < 0.05) in the bacterial population in both upper and lower regions of pneumatophores between different stations. Production of extracellular enzymes namely amylase, cellulase, lipase and phosphatase were screened in the isolated strains. The study showed that phosphatase producing bacteria (78%) was predominant, followed by lipase (75%), cellulase (71%) and amylase (52%). The study indicated the fact that the dynamic characteristics of mangroves provides a nurturing site for diverse bacteria, which were even capable to produce various enzymes.

Mangrove, pneumatophores, heterotrophic bacteria, enzymes