Role of bacterial extracellular polymeric substances (EPS) in uptake and accumulation of co-contaminants
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Coexistence of many contaminants in effluents discharged from industries is a serious environmental concern, even though these contaminants can individually be transformed into less toxic forms, but very few studies have reported simultaneous treatment of such contaminants. Present work was aimed at investigating the capability of extracellular polymeric substances from Bacillus subtilis MB378 for simultaneous uptake and accumulation of malachite green dye and selected metals (Cr, Cu and Cd). EPS showed highest uptake of cadmium (95.31%) at a rate of 1.04 mg g−1 without any dye addition. Chromium removal efficiency of 91.12% combined with malachite green was observed with a unit adsorption rate of 0.54 mg g−1, while 90.98% of copper removal was recorded in the presence of malachite green dye with highest binding capacity of 1.84 mg g−1 compared to individual metal ions. However, a reduction in color removal efficiency was noticed for malachite green in combination with metals compared to dye molecules alone. Quantification of decolorization revealed 94.91% removal of dye molecules by bacterial cells with EPS following bacterial cells without EPS (87.02%) and EPS (82.34%). Highest dye binding affinities of 0.66 and 0.64 mg g−1 were observed on combining the dye with chromium and cadmium, respectively. The formation of new peaks, disappearance and shifting of exiting in the UV–Vis absorption and FTIR spectra suggested possible adsorption and accumulation of dye combined with metals onto the charged or ionizable functional groups present on EPS surface, indicating EPS from B. subtilis MB378 as promising adsorbent in terms of potential pollutant removal and remediation.
KeywordsBacillus subtilis Exopolysaccharides Dye binding Metal adsorption Co-contaminants uptake
Authors are grateful to all those research laboratories and universities who helped in accomplishing this research work.
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Conflict of interest
Authors declare that they have no conflict of interest.
- Deepali KK, Gangwar KK (2010) Metals concentration in textile and tannery effluents, associated soils and ground water. N Y Sci J 3(4):82–89Google Scholar
- Gawali AA, Nanoty VD, Bhalekar UK (2014) Biosorption of heavy metals from aqueous solution using bacterial EPS. Int J Life Sci 2(4):373–377Google Scholar
- Gupta B (2012) Isolation and characterization of naphthalene degrading bacteria. Asters dissertation at Department of Biotechnology and Environmental Sciences, Thapar University, PatialaGoogle Scholar
- Halimoon N, Yin RGS (2010) Removal of heavy metals from textile wastewater using zeolite. Environ Asia 3:124–130Google Scholar
- Lei Z, Yu T, Ai-Zhong De-Zhi S (2012) Spectral analysis of Cd, Zn and Pb adsorption by extracellular polymeric substances from activated sludge. J Residuals Sci Technol 9(1):29–39Google Scholar
- Maddhinni VL, Vurimindi HB, Yerramilli A (2006) Degradation of Azo dye with horse radish peroxidase (HRP). J Indian Inst Sci 86:507–514Google Scholar
- Mahmood R, Sharif F, Ali S, Hayyat MU (2013) Bioremediation of textile effluent by indigenous bacterial consortia and its effects on Zea mays L. CV C1415. J Anim Plant Sci 23(4):1193–1199Google Scholar
- Moppert X, Le-Costaouec T, Raguenes G, Courtois A, Simon-Colin C, Crassous P, Costa B, Guezennec J (2009) Investigations into the uptake of copper, iron and selenium by a highly sulphated bacterial exopolysaccharide isolated from microbial mats. J Ind Microbiol Biotechnol 36(4):599–604CrossRefGoogle Scholar
- Olukanni OD, Adenopo A, Awotula AO, Osuntoki AA (2013) Biodegradation of Malachite green by extracellular laccase producing Bacillus thuringiensis RUN1. J Basic Appl Sci 9:543–549Google Scholar
- Patel SJ (2016) Review on biosorption of dyes by fungi. IJIRSET 5(1):2347–6710Google Scholar
- Sultan S, Mubashar K, Faisal M (2012) Uptake of toxic chromium (VI) by biomass of exopolysaccharides producing bacterial strains. Afr J Microbiol Res 6(13):3329–3336Google Scholar
- Tang J, Xu G, Li G, Spinosa L (2011) Adsorption properties of chromium (VI) on extracellular polymeric substances (EPS). In: Electric technology and civil engineering (ICETCE), 2011, international conference on Lushan, pp 983–986. https://doi.org/10.1109/icetce.2011.5776119