Scleroglucan production by Sclerotium rolfsii ATCC 201126: Influence of the carbon source

Abstract

Scleroglucan is a β-D-(1,3)-(1,6)-glucan produced by Sclerotium rolfsii ATCC 201126. This neutral water-soluble exopolysaccharide (EPS) was produced by submerged culture in MP20 liquid medium (sucrose: 20 g/L; initial pH: 4.5). The influence of 9 different simple and complex carbon sources on scleroglucan, biomass and oxalic acid production was evaluated. Batch fermentation processes were carried out in Erlenmeyer flasks at 30ºC and 250 rpm during 72 h. Higher EPS production (7 g/L) was obtained with sucrose and maltose as C-source. Biomass was significantly increased with maltose (~9 g/L) and soluble starch (9.6 g/L). Variable concentrations of oxalic acid were observed depending on the C-source used. The possibility to select appropriated culture conditions for S. rolfsii ATCC 201126 according to the product of interest was demonstrated. Additionally, biomass and EPS production obtained with molasses as C-source would allow to propose the use of low-cost substrates for the production of high-added value metabolites.