Lactobacillus Archives - Revista Brasileira de Ginecologia e Obstetrícia
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2015;37(9):417-420
DOI 10.1590/SO100-720320150005217
To investigate the influence of Lactobacillus rhamnosus in the expression of virulence factors of Candida albicans in vitro.
A suspension of L. rhamnosus was initially grown in MRS agar. The other day, Sabouraud dextrose agar was added on the growth of lactobacilli and C. albicans was seeded for 24, 48 and 72 hours. Candida strains were then isolated for investigation of the ability of biofilm formation, by means of cultivation into 96 wells plaque, and reading the optical densities and counting colony forming units per mL. Also the ability of germ tube formation was investigated, after incubation in horse serum and counting of 200 cells. The results were compared to Candida strains grown in the absence of L. rhamnosus, using Student's t test for statistical analysis.
there was a significant reduction in the growth of C. albicans in the presence of lactobacilli after 24, 48 or 72 hours. Significant reduction was also observed in germ tube formation after interaction for 48 or 72 hours. For biofilm formation, no statistically significant difference was observed between the Candida strains grown in the presence or absence of lactobacilli.
The results suggest that L. rhamnosus is able to influence significantly the growth and expression of virulence factors of C. albicans in vitro, and may interfere with pathogenicity of these micro-organisms.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2015;37(9):417-420
DOI 10.1590/SO100-720320150005217
To investigate the influence of Lactobacillus rhamnosus in the expression of virulence factors of Candida albicans in vitro.
A suspension of L. rhamnosus was initially grown in MRS agar. The other day, Sabouraud dextrose agar was added on the growth of lactobacilli and C. albicans was seeded for 24, 48 and 72 hours. Candida strains were then isolated for investigation of the ability of biofilm formation, by means of cultivation into 96 wells plaque, and reading the optical densities and counting colony forming units per mL. Also the ability of germ tube formation was investigated, after incubation in horse serum and counting of 200 cells. The results were compared to Candida strains grown in the absence of L. rhamnosus, using Student's t test for statistical analysis.
there was a significant reduction in the growth of C. albicans in the presence of lactobacilli after 24, 48 or 72 hours. Significant reduction was also observed in germ tube formation after interaction for 48 or 72 hours. For biofilm formation, no statistically significant difference was observed between the Candida strains grown in the presence or absence of lactobacilli.
The results suggest that L. rhamnosus is able to influence significantly the growth and expression of virulence factors of C. albicans in vitro, and may interfere with pathogenicity of these micro-organisms.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2009;31(4):189-195
DOI 10.1590/S0100-72032009000400006
PURPOSE: to identify species of lactobacillus isolated from the vaginal contents of healthy and asymptomatic women, determining the most prevalent species and characterizing them phenotypically. METHODS: lactobacillus have been isolated in selective milieu from samples of the vaginal contents of 135 women without complaints of vaginal secretion, and with negative laboratorial diagnosis of vaginal infection, followed up at an outpatient clinic. After being identified by multiplex PCR, the isolates have been submitted to RNAr 16S gene sequencing, when necessary. They have also been evaluated concerning the production of lactic acid, H2O2, bacteriocins and the ability to adhere to epithelial cells. RESULTS: eight-three lactobacillus strains were isolated and identified, L. crispatus (30.1%), L. jensenii (26.5%), L. gasseri (22.9%) e L. vaginalis (8.4%), being the prevalent species. Only 20 of those isolates did not present H2O2 production, in detectable amounts. From the 37 strains selected for the test of adhesion to the epithelial cells, 12 presented 50 to 69% of adhesion, 10 presented 70% or more, and the remaining, little or no adhesion at all. None of the tested strains produced bacteriocins. CONCLUSIONS: the lactobacillus species more prevalent in women without vulvovaginitis, isolated in selective culture milieu and identified by molecular methods were L. crispatus, L. jensenii and L. gasseri. Besides the fact of being more prevalent, these strains also presented better production of H2O2, and reached lower pH values in the culture milieu.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2009;31(4):189-195
DOI 10.1590/S0100-72032009000400006
PURPOSE: to identify species of lactobacillus isolated from the vaginal contents of healthy and asymptomatic women, determining the most prevalent species and characterizing them phenotypically. METHODS: lactobacillus have been isolated in selective milieu from samples of the vaginal contents of 135 women without complaints of vaginal secretion, and with negative laboratorial diagnosis of vaginal infection, followed up at an outpatient clinic. After being identified by multiplex PCR, the isolates have been submitted to RNAr 16S gene sequencing, when necessary. They have also been evaluated concerning the production of lactic acid, H2O2, bacteriocins and the ability to adhere to epithelial cells. RESULTS: eight-three lactobacillus strains were isolated and identified, L. crispatus (30.1%), L. jensenii (26.5%), L. gasseri (22.9%) e L. vaginalis (8.4%), being the prevalent species. Only 20 of those isolates did not present H2O2 production, in detectable amounts. From the 37 strains selected for the test of adhesion to the epithelial cells, 12 presented 50 to 69% of adhesion, 10 presented 70% or more, and the remaining, little or no adhesion at all. None of the tested strains produced bacteriocins. CONCLUSIONS: the lactobacillus species more prevalent in women without vulvovaginitis, isolated in selective culture milieu and identified by molecular methods were L. crispatus, L. jensenii and L. gasseri. Besides the fact of being more prevalent, these strains also presented better production of H2O2, and reached lower pH values in the culture milieu.