Technological characterization of vaginal probiotic lactobacilli: resistance to osmotic stress and strains compatibility

JESSICA ALEJANDRA SILVA; ANTONELLA MARCHESI; BIRGITT WIESSE; MARIA ELENA FÁTIMA NADER

JOURNAL OF APPLIED MICROBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020 vol. 127 p. 1835 - 1847

1364-5072

Aims: The aim was to evaluate the osmotic stress resistance of vaginalbeneficial probiotic strains, their growth kinetics and parameters when growingin salt-added culture media, and their compatibility to go further in the designof a probiotic formula for reconstitution of vaginal microbiome in women.Methods and Results: The resistance to osmotic stress of the lactobacilli wasevaluated by determining their growth in MRS (as control) added with NaCl(2–8%). The most resistant strains were Lactobacillus gasseri CRL1509, L.rhamnosus CRL1332 and L. reuteri CRL1327 selected by statistical approachesand growth parameters. Electron microscopy was applied to determinechanges. They maintain probiotic properties and viability. Some strains showedincompatibility, then they cannot be included in multistrain formulas.Conclusions: The resistance to different salt concentrations in vaginallactobacilli is strain-specific, because the behaviour is different in strainsidentified into the same species. The resistance is not related to the metabolicgroups.Significance and Impact of the Study: The resistance and survival to extremeosmotic resistance is one of the specific requirements of beneficial bacteriaafter the technological processes for their inclusion in probiotic formulas, in away to express their beneficial characteristics and exert the effect on the host.