Survey for Urease activity in the halophilic prokaryotes isolated from Chabar solar salterns

Urease has important application in bioremediation and bioconsolidation. In bioconsolidation process released ammonium groups from urea hydrolysis induce the precipitation of calcite which can use as cement to bind small particles in soil. This process may apply in sand and dust precipitation. Halophilic urease which is active in dry and salty soil with alkali pH is suitable to use in most soils of Iran. In This study the ureolytic activity were investigated in halophilic prokaryotes isolated from Chabahar solar salterns. Samples were diluted and cultured in SW medium supplemented by 10 and 20% NaCl and incubated at 37 °C for one month. A total of 50 extreme and moderate halophilic strains were screened for urease activity in SW media containing urea and phenol red as pH indicator. Twenty-four of the strains produced urease. Based on colony to halo zone diameter, six of the strains were selected as high enzyme producers. They were phylogenetically related and Bacillus. According to phenol -hypochlorite to Haloferax, Haloarcola, Halogeometricum, Halostagnicola, Rhodovibrio quantitative assay method, strain E59 was selected for further analysis. Characterization of enzyme and its application in biocosolidation are in progress.

Keywords:

Urease , Chabahar solar salterns , calcite precipitation , Halophilic prokaryotes , biocosolidation