Dental caries is an infectious disease that is caused by the interaction between the host, the diet, and a diverse microbial community. This study illustrated the anticariogenic effects of THYJ-15 against Streptococcus mutans, a major agent of dental caries. THYJ-15 was identified as Latilactobacillus sakei subsp. sakei through 16S rRNA sequencing, with a similarity of 99.72% to L. sakei subsp. sakei JCM 1157T. The cell-free supernatant of L. sakei subsp. sakei THYJ-15 observed MIC values of 10 mg/mL and MBC values of 20 mg/mL against S. mutans KACC 16833T. The cell-free supernatant of L. sakei subsp. sakei THYJ-15 showed significant inhibitory effects on biofilm formation, acid production and glucosyltransferases(GTFs) production against S. mutans. As a results, it was confirmed that L. sakei subsp. sakei THYJ-15 is a lactic acid bacterium possessing notable anticariogenic effects. Accordingly, L. sakei subsp. sakei THYJ-15 is expected to have great potential to be used as a basic substance for dental caries treatment caused by S. mutans.

Dental caries is an infectious disease accompanied by the destruction of teeth. It is a multifactorial disease caused by the interaction between microbes in dental plaque and food, with cariogenic Streptococcus mutans being one of the primary causes. In this study, the antimicrobial and antibiofilm activities of Lactiplantibacillus plantarum THK-j112 isolated from Kimchi, a traditional fermented food, against S. mutans were investigated. Furthermore, this paper also showed the possibility of developing this strain. After analyzing the 16S rRNA sequence, strain THK-j112 was named L. plantarum THK-j112 as it shared 99.93% similarity with L. plantarum ATCC 14917T. Both L. plantarum THK-j112 and L. plantarum ATCC 14917T demonstrated MIC values of 5 mg/mL and MBC values of 10 mg/mL against S. mutans KACC 16833T. The study confirmed that L. plantarum THK-j112 exhibited significant concentration-dependent inhibitory effects on biofilm formation, acid production, and glucosyltransferases(GTFs) production. Regarding hemolytic activity, Bacillus cereus ATCC 14579T, used as a positive control, was confirmed to cause hemolysis, whereas L. plantarum THK-j112 did not cause this phenomenon. Additionally, except for gentamicin, the antibiotic resistance test revealed a lower value than the MIC cut-off value for each antibiotic, indicating no resistance. Based on the findings, L. plantarum THK-j112 is expected to be useful in the food industry, such as functional food, as a lactic acid bacterium with antimicrobial and antibiofilm effects.

Ginsenosides, ginseng saponin, are the principal components responsible for the pharmacological and biological activities of ginseng. In order to improve absorption and biological activities, the biotransformation of major ginsenoside to minor ginsenoside, as the more active compound, is required. In this study, we isolated Lactobacillus brevis THK-D57, which has high β-glycosidase activity, from Kimchi. The major ginsenoside Rb₁ was converted to the minor ginsenoside ‘compound K’ during the fermentation of L. brevis THK-D57. The results propose that the biotransformation pathway to produce compound K is as follows: ginsenoside Rb₁→ginsenoside Rd→ginsenoside F₂→ginsenoside compound K.

To investigate effects on the growth and ginsenosides accumulation in ginseng hairy root, potassium phosphate was supplemented with 1.25, 2.5, and 5.0 mM concentration in 1/2 MS medium, respectively. Potassium phosphate supplement was increased the biomass and ginsenosides accumulation when it was dose at the concentration of 1.25 mM. And the growth rate of hairy root in the light condition was higher than in dark condition. The highest contents and productivity of ginsenosides were observed at the supplement of 1.25 mM potassium phosphate at the 7th day after the culture onset. Ginseng hairy root cultured in 20 L bioreactor supplemented with 1.25 mM KH2PO4 was increased the growth with 1,609 g (F·W) and ginsenosides content with 11.09 mg than those in control.

고려 인삼(Panax ginseng)의 뿌리로부터 ribulose-1,5-bisphosphate carboxylase small subunit(rbcS) 유전자를 선발하여 sequence 분석을 실시하였다. 고려 인삼 rbcS cDNA는 790 bp 염기로 구성되어 있으며, 183개의 아미노산(pI 8.37)을 코드하는 549 bp의 ORF를 가지고 있고 단백질의 분자량은 20.5 kDa으로 추정되었다. 인삼 rbcS는 기존에 보고된 것과 유사성을 나타내었으며, Helianthus annuus(CAA68490)에서 분리된 것과 78%의 높은 상동성을 보였다. 기존에 데이터베이스에 축적되어 있는 다른 식물체로부터 분리된 rbcS와 아미노산 서열을 비교한 결과 인삼의 ybcS는 H. annuus (CAA68490), C. morifolium (AAO25119), L. sativa (Q40250)와 밀접한 유연관계에 있는 것으로 조사되었다.