Optimization of the production and stress resistance of the probiotic Lactobacillus fermentum K73 in a submerged bioreactor using a whey-based culture medium

• Published in: CYTA: journal of food 2018-01, Vol.16 (1), p.1064-1070
• Main Authors: Aragón-Rojas, Stephanía, Ruiz-Pardo, Ruth Y., Hernández-Sánchez, Humberto, Quintanilla-Carvajal, María Ximena
• Format: Article
• Language: English
• Subjects: Agitation; Bile salts; Bioreactors; Cell culture; culture conditions optimization; Lactic acid; Lactobacillus fermentum; Lactobacillus fermentum K73; Lag phase; Microorganisms; optimización de condiciones de cultivo; Optimization; pH effects; probiotic production; Probiotics; producción de probióticos; resistencia a estrés; Response surface methodology; Salts; stress resistance; suero lácteo; Whey; Yeast
• ISSN: 1947-6337; 1947-6345
• DOI: 10.1080/19476337.2018.1527785

The aim of this study was to develop a culture medium based on whey for the improvement of the probiotic characteristics of Lactobacillus fermentum K73 in submerged culture. Response surface methodology was used to determine the effects of culture conditions (whey and yeast extract concentration, pH, and agitation) on growth and probiotic characteristics of the lactic acid bacterium. Results showed that whey and yeast extract concentrations were the most influential variables in the responses. The conditions for maximal final cell count (10.783 log (CFU/ml)), minimal lag phase duration (1.022 h), minimal decrease under acid stress conditions (0.097 log (CFU/ml)) and a decrease in biomass in the presence of 0.3% bile salts of 2.58 log (CFU/ml) were: 44.6 g/L of whey, 25 g/L of yeast extract, pH 5.5 and an agitation rate of 100 rpm. These results are the first to indicate that the optimization of the expression of probiotic characteristics of microorganisms is feasible.