Optimization of culture condition for biomass and bacteriocin production of vaginal Lactobacillus salivarius

MARÍA SILVINA JUÁREZ TOMÁS; VIRGINIA OCAÑA; AÍDA DE RUIZ HOLGADO; MARÍA ELENA NADER-MACÍAS

Tafí del Valle, Tucumán, Argentina

Jornada; XVI Jornadas Científicas de la Sociedad de Biología de Tucumán; 1999

Sociedad de Biología de Tucumán

Lactobacilli are the predominant microorganisms in the urogenital tract where they protect from pathogen colonisation. In previous works L. salivarius subsp. salivarius CRL 1328, able to produce a bacteriocin–like substance active against Enterococcus faecalis, E. faecium y Neisseria gonorrhoeae, was characterized. By the potential technological use of this microorganism, conditions for optimal growth and bacteriocin production are studied in this work. Different growth culture media were emlyed: MRS, LAPTg, M17 and  BHI, all at pH=6.5. L. salivarius inocula were 2 and 5%. The growth was determined spectrophotometrically and the bacteriocin titer by the plaque method. Higher growth was obtained in MRS, with maximal biomass after 24 hs at 37°C, (m=0.76, g=1.31) and with maximal bacteriocin concentration after 6 hs (640 AU/ml), independently of the initial inoculum. Those culture media with a maximal bacteriocin concentration were LAPTg and M17 after 6 and 9 hs showing a titer of 1280 UA/ml. BHI was not adequated for biomass obtention and bacteriocin production In Laptg, M17 and BHI different maximal DO were obtained depeding on the initial inoculum. Our results indicate that MRS is the optimal medium for biomass obtention while LAPTg and M17 for bacteriocin production of L salivarius, which would be included in a probiotic for the vaginal tract.