Occurrence and Abundance of Phosphatase-Producing Bacteria in Mangrove Ecosystem

Abstract

The study detailed the isolation and characterization of phosphatase producing bacteria (PPB) from rhizospheric, pneumatophoric and bulk sediments of Avicennia marina along Mumbai coast, India and also estimated alkaline phosphatase activity in sediment in addition to the Phosphatase enzymatic activity of isolates. The inorganic-organic nature of phosphorus was also examined. About, 42 PPB were isolated and identified from the sediment samples. 16S rDNA sequence revealed that all the isolates belong to the genus Bacillus except the one which belong to Geobacillus in the environment and B. anthracis str. Ames showed the phosphatase-producing activity of 84.11±0.01 µg p-NP released per 1×108 cfu in 72 hrs. The isolates, B. cereus strain APT23 and B. thuringiensis strain INRS4 showed the next best phosphatase activity. It was observed that PPB was very much abundant in A. marina mangroves. The pneumatophoric sediment showed significantly higher number of PPB with higher alkaline phosphatase activity, inorganic P and low organic P than those of other sediment types indicating that pneumatophoric region of A. marina harbours favourably the phosphatase-producers than the rhizospheric or bulk sediments and forms the first reference worldwide depicting this relationship. The isolates that showed higher phosphatase-producing potentials can be explored for using as phosphatic bio-fertilizer to enhance the agricultural, aquacultural and mangrove productivity on a larger scale.