CONICET | Buscador de Institutos y Recursos Humanos

TECHNOLOGICAL EVALUATION OF SURFACTIN PRODUCTION BY BATCH FERMENTATION WITH Bacillus subtilis, Bacillus licheniformis y Bacillus amyloliquefaciens.Diaz Alfaro, M1; Lara, J1; Baigorria, V2; Ferrero, M1,2; Lucca, ME1,21PROIMI-CONICET, Belgrano y Caseros, 4000, Tucumán, Argentina. 2 Microbiología Superior, FBQyF, UNT, Ayacucho 491, Tucumán, Argentina. mariaesterlucca@gmail.com Production media design for biosurfactans production with low cost non-conventional substrates is an important parameter to the technical evaluation and the commercial feasibility of the microbial bioprocess. Batch fermentation under controlled ambient conditions allow to increase yields and productivity of the bioprocess. Biosurfactants lower viscosity and increase oil emulsion im water. Another relevant property of surfactin is the antimicrobial activity against a wide range of microorganisms. In this work the capacity of surfactin production of three Bacillus strains: subtilis, amyloliquefaciens and licheniformis in batch fermentation was evaluated. The main substrate used was sacarose 25 g/L and salts, without yeast extract in ordr to decrease costs. Work volume was 1L and fermentation was carried on during 24 h with agitation. Surfactin was collected by extraction of foam during the first 15 h of fermentationSurfactin was partially purified by acid precipitation with clorhidric acid and extraction with clorofom-methanol. In all cases it was observed surfactin production in the range of 0.3 to 0.4 g /L and 88% of produced surfactin was present in the foam. This methodology allowed to simplify the downstream process with a positive impact on the recuperation costs. The results obtained show that the production medium without yeast extract that can be utilized for surfactin production with Bacillus strains and represents an alternative of lower cost.