Biodegradation of geosmin in drinking water by novel bacteria isolated frombiologically active carbon

Three strains of Gram-negative bacteria capable of removing geosmin from drinking water were isolated from biologically activecarbon and identified to be Chryseobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp. based on physio-biochemistry analysisand 16S rRNA gene sequence analysis. Removal e ciencies of 2 mg/L geosmin in mineral salts medium were 84.0%, 80.2% and74.4% for Chryseobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp., respectively, while removal e ciencies of 560 ng/Lgeosmin in filter influent were 84.8%, 82.3% and 82.5%, respectively. The biodegradation of geosmin was determined to be a pseudofirst-order reaction, with rate constants at 2 mg/L and 560 ng/L being 0.097 and 0.086 day??1, 0.089 and 0.084 day??1, 0.074 and 0.098day??1 for the above mentioned degraders, respectively. The biomass of culture in the presence of geosmin was much higher than thatin the absence of geosmin.