Bioconversion of l-arabinose and other carbohydrates from plant cell walls to α-glucan by a soil bacterium, Sporosarcina sp. N52

Abstract A Gram-positive bacterium, N52, that produces intracellular glucanfrom l - arabinose, was isolated from soil and identified as Sporosarcinasp. according to rRNA gene sequence analysis and physiological/biochemical characterizations. Glucanproduction by N52 increased significantly in the exponential phase of aerobic liquid culture and was maintained at the highest level during the stationary phase, reaching 37.0% of the cell dry weight. The glucanwas also produced from other tested sugars originating from plant cell walls and was composed exclusively of α-1,4- and α-1,6-glucosidic linkages. When distillery waste was treated with N52 for 72 h, the total organic carbon(TOC), chemical oxygen demandand biochemical oxygen demandwere reduced by 42.6%, 45.9% and 82.5%, respectively. Bacterial cells accumulated 31.9% of glucanper cell dry weight, fixing 16.0% of the TOC in the soluble fraction. Thus, this strain could provide us with a new process for waste management, including the bioconversionof organic materials to the valuable byproduct, α- glucan.