Purification and characterization of exopolysaccharide bioflocculant produced by heavy metal resistant Achromobacter xylosoxidans. (10th February 2016)

• Record Type: Journal Article
• Authors: Subudhi, Sanjukta; Bisht, Varsha; Batta, Neha; Pathak, Mihirjyoti; Devi, Arundhuti; Lal, Banwari
• Is Part Of: Carbohydrate polymers. Volume 137(2016)
• Page Start: 441
• Page End: 451
• Publication Date: 2016-02-10
• Subjects: Achromobacter xylosoxidans -- Bioflocculant -- Biopolymer -- Exopolysaccharide -- FTIR and NMR -- LC–MS and SEM -- Flocculation -- Heavy metals; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2015.10.066
• Languages: English
• ISSNs: 0144-8617

Abstract

Highlights: Exopolysaccharide bioflocculant produced by Achromobacter xylosoxidans TERI L1. FTIR and NMR and LC–MS confirmed the bioflocculant as an exopolysaccharide heteropolymer, glycoprotein. First time reports for 90% biosorption of Zn, Pb, Ni, Cd and Cu by A . xylosoxidans . Maximum lead adsorption (1100 mg L −1 ) reported till date by this TERI L1 strain. Bioflocculant composed of 75% sugar and 11.5% protein. 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.