Conservation in probiotic preparations of Lactobacillus with inhibitory capacity on other species

Strains of Lactobacillus isolated from dairy products and genital tract com peted with Candida albicans through a membrane of 12000 dalton cut-off. Thi s inhibition was due to hydrogen peroxide and was trypsin-stable, heat-sens itive and antagonized by catalase. Lactobacillus coming from "starters" sho wed antimicrobial activity against fungus isolated in a yogurt factory. Pen icillium, Alternaria, Phialophora, Microsporum and Candida spp. were inhibi ted when 10(2) spores were inoculated in the assay. No inhibition was obser ved with 10(5) spores. Besides, one of 21 Lactobacillus strains isolated fr om the vaginas of healthy women inhibited pathogenic bacteria by means a ba cteriocin trypsin-sensitive, heat-stable and retained by dialysis membrane. Tablets for future probiotic use were prepared and the viability of bacter ia was assayed using media with different compositions. Pharmaceutical prep arations with polyethyleneglycol was the best formulation for the Lactobaci llus viability, the counts remained between 10(7) and 10(6) cfu/tablet for up to 1 year.