Type of presentation: Poster

LS-6-P-6034 The role of bacterial consortium in in-situ bioremediation of tannery waste water and detoxification study of chromium in HepG2 cell line

Srivastava S.1,2, Jaiswal P. K.1,3, Thakur I. S.1
11. School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India , 22. Amity School of Earth and Environmental Sciences, Amity University, Gurgaon, India , 33. The research institute of the McGill University health centre 1650 cedar Avenue Montreal Canada
shailisrivastava05@gmail.com

The role of bacterial consortium in in-situ bioremediation of tannery waste water and detoxification study of chromium in human hepatoma cell line
Shaili Srivastava1, 2, Prashant Kumar Jaiswal 1,3 and Indu shekhar Thakur1
1. School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
2. Amity School of Earth and Environmental Sciences, Amity University, Gurgaon, India
3. The research institute of the Mcgill University health centre 1650 cedar Avenue Montreal Canada
Abstract
Tanneries are responsible for environmental pollution as it uses huge amount of chromium sulphate (CrIII) and pentachlorophenol (PCP) in the leather tanning processes to inhibit the growth of microorganism. Effluent contaminated by metals and chlorinated organic compounds are difficult to remediate. Chromium sulphate [Cr (III)] and pentachlorophenol (PCP) are widely used as tanning agent and biocide for the leather preparation in tanneries. Pentachlorophenols are highly toxic and recalcitrant compound. Chromium (III) may be converted in to chromium (VI) form in aquatic environment which is highly toxic and carcinogenic in nature. Bacterium consortiums obtained from tannery soil sediment were used for bioremediation and bioconversion of PCP and chromium from the tannery waste water. A bacterium isolated from tannery consortium was identified as Serratia sp. by 16S rDNA analysis. Bacterium reduced Cr(VI) to Cr(III) by a homodimer enzyme, chromate reductase, with a monomer molecular mass of 40 kDa. The potency of Serratia sp. for degradation of pentachlorophenol was determined by HPLC after formation of tetrachlrohydroquinone and chlrorohydroquinone. Bioremediation of chromium and PCP were tested in bioreactors in sequential way where bacterium treated effluent subsequently treated by fungi showed reduction of chromium (82%) and PCP (85%) after 120 hrs. Biosorption of chromium was determined by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The toxicity of Cr(VI) was also determined in vitro HepG2 cell line by IC50, Ethoxyresorufin-O-deethylation activity, Fluorescence-activated cytometry sorter analysis and Confocal laser scanning microscopy indicated detoxification of chromium after adsorption by bacterium.

We thanks the Council of Scientific and Industrial Research, Government
of India,NewDelhi, for providing a Research Associate fellowship
and a contingency grant.We also thanks to advanced instrumentation facility of Jawaharlal Nehru
University, and All India Institute of Medical Sciences New Delhi, India, for providing the TEM, SEM-EDX, fluorescent microscope facility.

Fig. 1: Figure 1 (a) Scanning Electron Microscopy (SEM) of exposed cell of bacterium (Serratia sp.) after tannery effluent treatment (b) SEM of tannery effluent treated fungal mycelium of Aspergillus niger .