HEAVY METAL TOLERANT BACTERIA ISOLATED AND DETECTED FROM THE EFFLUENT OF HAZARIBAGH TANNERY INDUSTRY IN DHAKA CITY

Abstract

The tanning industry is held to be an activity with the high budding for environmental pollution all over the world. Many Bacterial strains isolated from natural resources have been found to possess unique properties which make them useful for environmental cleans ups. So it is very important to find out an alternative ecofriendly way for the treatment of contaminated effluent. The objective of this study was to isolate, explore and pick out natural occurring bacteria capable of reducing heavy metals from tannery effluent collected from the Hazaribagh tannery industry of Dhaka. The pH value of all the effluents samples were ranged from 7.12 to 7.91. Five bacterial strains were confirmed as Bacillus bataviensis, Bacillus aryabhattai, Micrococcus antarcticus, Bacillus proteolyticus and Bacillus paranthracis on the basis of their morphological, cultural, biochemical, and 16S rRNA gene sequencing. Among these five strains, Bacillus bataviensisD1 exhibited higher resistance to cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and arsenic (As) up to the amount of 550 µg/mL, 500 µg/mL, 500 µg/mL, 1050 µg/mL and 1100µg/mL respectively. Bacillus aryabhattai D2 and Micrococcus antarcticus D3 showed similar result to chromium (Cr) and Lead (Pb), but Bacillus proteolyticus B1 showed higher resistance to nickel (Ni) that is up to 250 µg/mL. From these results, it can be suggested that the identified heavy metal-adapted bacteria could be useful for the biosorption of heavy metal contaminated effluent.