Probiotic Lactic Acid Bacteria for Vaginal Application. Optimization of Biomass Production and Freeze-Drying Conditions

Probiotic formula for the vaginal tract must contain high numbers of viable beneficial bacteria that maintain their characteristics during production and further storage, in order to exert claimed probiotic effect. Four strains—Lactobacillus gasseri CRL1320, Limosilactobacillus reuteri CRL1324, Ligilactobacillus salivarius CRL1328 Lacticaseibacillus rhamnosus CRL1332—originally isolated from vagina healthy women exhibiting properties were evaluated. Therefore, optimization growth parameters dry biomass with viability while preserving features strains is a great challenge. Different conditions MRS medium set up laboratory bioreactor; two initial pH agitation recorded speeds static or controlled fermentations. Production 37 °C 6.5 5.5-MRS 150 75 rpm stirring used CRL1329 CRL1332 strains, respectively, free CRL1324 probiotics allowed us obtain maximal cell counts. However, 12 h fermentation, yields 19.3, 16.2 15.2 g/L achieved when CRL1329, grown MRS. The highest yield strain was produced under MRS-initial fermentation conditions. To preserve viability, freeze-drying carried out presence different cryoprotective agents. Thus, (10.9–11.8 log CFU/g) survival rates between 91.3 95.6% attained 10% trehalose (L. L. salivarius), lactose rhammosus) + sucrose mix gasseri). When stability post-freeze-drying storage evaluated, showed remarkably higher recovery stored at 4 than 25 3 months, respectively. In addition, surface affected extents depending on strain, protective agent time/temperature. Critical factors conditions, drying process lactobacilli optimized view design formula.