title: Purification and characterization of exopolysaccharide bioflocculant produced by heavy metal resistant Achromobacter xylosoxidans.
abstract: Optimization of process parameters enhanced bioflocculating activity of 'Achromobacter xylosoxidans strain TERI L1' from 75% to 83.3% in absence of heavy metals, which decreased to 73% in presence of multi-metals. 'TERI L1' could adsorb 90% of multi-metals when grown in presence of 1250 mg L(-1) Zn, 2 mg L(-1) Cd, 30 mg L(-1) Pb, 200 mg L(-1) Ni and 90 mg L(-1) Cu and could adsorb 1100 mg L(-1) of Pb when grown in presence of 1500 ppm lead nitrate. The bioflocculant was purified and characterized. Bioflocculant yield was 5 g L(-1). Fourier transform infrared spectrum indicated presence of carboxyl, hydroxyl, amino groups, typical of glycoprotein. Spectroscopic analysis of bioflocculant by nuclear magnetic resonance revealed that it is a glycoprotein. LC-MS analysis confirmed the bioflocculant as a carbohydrate hetero polymer. Bioflocculant was composed of 75% total sugar with 72.9% neutral sugar and 11.5% protein. Scanning Electron Micrography revealed effective flocculation of kaolin clay by purified exopolysaccharide bioflocculant.
authors.affiliation: Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, Lodi Road, New Delhi, India. Electronic address: ssubudhi@teri.res.in.
authors.forename: Sanjukta
authors.initials: S
authors.lastname: Subudhi
authors.affiliation: Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, Lodi Road, New Delhi, India.
authors.forename: Varsha
authors.initials: V
authors.lastname: Bisht
authors.affiliation: Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, Lodi Road, New Delhi, India.
authors.forename: Neha
authors.initials: N
authors.lastname: Batta
authors.affiliation: The Resource Management and Environment Section, Life Science Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam, India.
authors.forename: Mihirjyoti
authors.initials: M
authors.lastname: Pathak
authors.affiliation: The Resource Management and Environment Section, Life Science Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam, India.
authors.forename: Arundhuti
authors.initials: A
authors.lastname: Devi
authors.affiliation: Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, Lodi Road, New Delhi, India. Electronic address: banwaril@teri.res.in.
authors.forename: Banwari
authors.initials: B
authors.lastname: Lal
mesh_terms: D042402:Achromobacter / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D005427:Flocculation; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism; D007854:Lead / Q000737:chemistry* / Q000494:pharmacology; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000378:metabolism
chemical_list: D006023:Glycoproteins; D011135:Polysaccharides, Bacterial; D007854:Lead
keywords: Achromobacter xylosoxidans; Bioflocculant; Biopolymer; Exopolysaccharide; FTIR and NMR; Flocculation; Heavy metals; LC–MS and SEM