Vaginitis, also known as vaginal infection and vulvovaginitis, is an inflammation of the vagina and possibly vulva. The three main kinds of vaginitis are bacterial vaginosis, vaginal candidiasis, and trichomoniasis. The purpose of this study was to characterize Lactobacillus plantarum MG989 and L. fermentum MG901 isolated from the vaginas of healthy Korean women in terms of their inhibitory activity against the vaginitis associated pathogens such as Gardnerella vaginalis and Candida albicans. Co-culture experiments showed that the two Lactobacillus strains MG989 and MG901 significantly reduced the viability of G. vaginalis and C. albicans. Also, the two strains were resistant to bile acid up to 1% and their autoaggregation rates were as high as 83.33%. Further studies are underway to demonstrate that the two strains can be applied as pharmaceutical agents for recovering healthy vaginal ecosystem.

Lactobacilli, the dominant species of microorganisms in the vaginal flora of healthy women, play important roles to prevent bacterial vaginosis and other sexually transmitted diseases. In this study, we carried out studies on stress adaptation prior to various stress treatment. We found that heat or salt adapted KLB46 showed higher cell viability than non adapted upon heat stress at 60 o C for 20 min. When chloramphenicol was added during the adaptation process, heat tolerance was abolished. This result suggested that de novo protein synthesis was essential during adaptation.

In this study, 52 ureolytic bacterial strains were newly isolated from various environments. From these, 2 strains (TB-15 and TB-22) were selected based on their high urease activity. XRD spectra clearly showed presence of various sequestration products such as calcite and strontianite in samples. TB-22 showed 20~30% higher survivability upon Sr concentration (20 mM) than Sporosarcina pasteurii KCTC 3558. TB-15 and TB-22 showed 80~90% higher survivability at pH 6 than S. pasteurii. The results demonstrated that the 2 isolates colud be good candidates for the bioremediation of Sr contaminated sites.

Microbially induced calcite precipitation is a naturally occurring biological process in which microbes produce calcite on the surface of the microorganisms by urease activity. In order to collect calcite forming bacteria (CFB) in Korea, we isolated 343 putative CFB strains from various environments over three year period (2011~2013) and selected 100 CFB strains. Average of calcite productivity was 10.56 mg/ mL. And average of ammonium concentration by urease activity was 8.00 µM. Two useful CFB strains of the others were analyzed by 16S rRNA and identified as Sporosarcina sp. and Viridibacillus arenosi. The CFB strains presented in this study are indigenous microorganisms in Korea and they are expected to be applicable to a variety of environments in the country.