김치 유래 Lactiplantibacillus plantarum THK-j112의 Streptococcus mutans에 대한 항균효과 및 항생물막 효과

유두나(Du-Na Yu),이은지(Eun-Ji Yi),정제용(Je-Yong Jung),이태후(Tae-Hoo Yi),국무창(Moochang Kook) 한국유산균프로바이오틱스학회 2023 Current Topic in Lactic Acid Bacteria and Probioti Vol.9 No.1

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.

김치 유래 유산균의 발효유 스타터로서의 가능성 평가

유두나(Du-Na Yu),이정은(Jeong-Eun Lee),국무창(Moochang Kook) 한국유산균프로바이오틱스학회 2023 Current Topic in Lactic Acid Bacteria and Probioti Vol.9 No.2

This study aimed to confirm the suitability of lactic acid bacteria isolated from Kimchi as starters for fermented milk by assessing their carbohydrate availability, enzyme activity, and growth characteristics. The isolates L. pentosus LK013 exhibited a 99.79% similarity to L. pentosus DSM 20314T, P. pentosaceus LK019 showed a 99.86% similarity to P. pentosaceus DSM 20336T, L. brevis LK030 displayed a 99.72% similarity to L. brevis ATCC 14869T, and L. brevis P215 demonstrated a 99.59% similarity to L. brevis ATCC 14869T. Regarding carbohydrate availability, P. pentosaceus LK019 exhibited higher availability of L-arabinose, L-rhamnose, N-acetylglucosamine, amygdalin, arbutin, esculin, salicin, and gentiobiose, as well as D-form carbohydrates compared to other strains. Meanwhile, L. brevis LK030 and L. brevis P215 were able to utilize pentoses such as L-arabinose and D-ribose, as well as hexoses such as D-galactose and D-glucose. On the other hand, L. pentosus LK013 demonstrated the ability to use L-arabinose, N-acetyl-glucosamine, esculin, D-ribose, D-glucose, D-fructose, D-cellobiose, and D-maltose. In addition, P. pentosaceus LK019 exhibited higher leucine arylamidase and valine arylamidase activities than others. L. pentosus LK013 was confirmed to have enzyme activities such as Lipase, Leucine arylamidase, valine arylamidase, β-glucuronidase, α-glucosidase, and β-glucosidase. L. brevis LK030 and L. brevis P215 demonstrated outstanding activity against lipid-hydrolyzing enzymes, specifically esterase and esterase lipase, which facilitate effective digestion in the human digestive system. Furthermore, they exhibited activity against α-galactosidase, which is responsible for decomposing non-absorbable raffinose and stachyose. The growth curve analysis of lactic acid bacteria revealed that all bacteria were capable of acid production, maintaining a low pH throughout proliferation. These results suggest that the isolates (L. pentosus LK013, P. pentosaceus LK019, L. brevis LK030, and L. brevis P215) can be used as starters in fermented milk.

치아우식을 유발하는 Streptococcus mutans에 대한 억제효과를 가진 김치 유래 유산균 Latilactobacillus sakei subsp. sakei THYJ-15

정제용(Je-Yong Jung),유두나(Du-Na Yu),권예지(Ye-Ji Kwon),이은지(Eun-Ji Yi),Nguyen Thi Minh Trang(Nguyen Thi Minh Trang ),국무창(Moochang Kook),이태후(Tae-Hoo Yi) 한국유산균프로바이오틱스학회 2023 Current Topic in Lactic Acid Bacteria and Probioti Vol.9 No.1

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.

모유 유래 유산균 Enterococcus faecalis BMSE-HMP005의 다제내성 균에 대한 항균효과

이정은(Jeong-Eun Lee),김수빈(Soo-bin Kim),유두나(Du-na Yu),조소연(So-Yeon Jo),김애정(Ae-Jung Kim),국무창(Moochang Kook) 한국식품과학회 2022 한국식품과학회지 Vol.54 No.2

본 연구에서는 모유 유래 유산균 E. faecalis BMSE-HMP005의 다제내성 균주에 대한 항균효과 및 probiotics로써 잠재적인 가능성을 확인하였다. E. faecalis BMSE-HMP005는 다제내성 균주 20주(Enterococcus spp., Staphylococcus spp., Escherichia spp., Pseudomonas spp., Salmonella spp., Klebsiella spp., Enterobacter spp.)에서 모두 MBC가 확인되어 다제내성 균주에 대한 우수한 항균효과를 입증하였다. 또한 RP-HPLC를 이용하여 배양액 내 bacteriocin을 확인하였으며, 이에 대한 분획은 gram 양성 및 gram 음성균주에서 모두 항균력이 나타나, E. faecalis BMSE-HMP005가 생산하는 bacteriocin의 광범위한 항균 스펙트럼을 입증하였다. E. faecalis BMSE-HMP005는 발암 화합물을 유발하는 β-glucuronidase에 대한 활성과 용혈성은 나타나지 않아 안전한 것으로 판단된다. E. faecalis BMSE-HMP005는 vancomycin에 대해서는 내성을 보이나, kanamycin (>0.058), ampicillin (>0.002), erythromycin (>0.002)은 EFSA 기준의 허용범위보다 낮은 MIC가 확인되었다. 또한 인공위액(pH 2.0) 및 인공 담즙산(0.3% bile acid) 조건에서 각각 98.67%, 95.70%의 생존율을 보였다. 이와 같은 결과는 본 연구에서 분리한 모유 유래 유산균 E. faecalis BMSE-HMP005가 다제내성 균주에 대한 우수한 항균활성을 갖는 probiotics로써 잠재적인 가능성을 보여준다. 따라서 건강기능식품의 기준 및 규격에 제시된 바와 같이 Enterococcus spp.는 항생제 내성 및 독성 유전자가 없는 경우에 한하여 probiotics로 사용이 가능한 고시하고 있어 E. faecalis BMSE-HMP005의 안전성에 대한 추가적인 검증이 필요할 것으로 판단된다. In this study, Enterococcus faecalis BMSE-HMP005 isolated from human breast milk demonstrated antimicrobial effects against multidrug-resistant (MDR) bacterial strains. The bacteriocin produced by E. faecalis BMSE-HMP005 was fractionated using reverse-phase high-performance liquid chromatography. This fraction showed antimicrobial effects against both gram-positive and gram-negative MDR bacteria. No hemolytic reactions were observed. E. faecalis BMSE-HMP005 was resistant to vancomycin; however, kanamycin, ampicillin, and erythromycin showed minimum inhibitory concentrations that were lower than the acceptable range provided by the European Food Safety Authority. For artificial gastric juice and bile acid, the survival rates were 98.67% and 95.70%, respectively. These results show the potential utility of E. faecalis BMSE-HMP005 as a probiotic with remarkable antimicrobial effects against MDR bacteria.

모유에서 분리한 Enterococcus faecalis의 다제내성 균에 대한 항용혈 및 항균 효과

이은지 ( Eun-ji Yi ),이정은 ( Jeong-eun Lee ),조소연 ( So-yeon Jo ),김수빈 ( Soo-bin Kim ),유두나 ( Du-na Yu ),국무창 ( Moochang Kook ),김애정 ( Ae Jung Kim ) 한국미생물 · 생명공학회 2021 한국미생물·생명공학회지 Vol.49 No.4

본 연구에서는 국내 건강한 산모의 모유에서 분리한 E. faecalis BMSE-HMP 4주의 용혈여부와 다제내성 균에 대한 항용혈 효능 및 항균 효과를 확인하였다. 분리 균주의 효소 활성을 측정 결과, E. faecalis BMSE-HMP 4주는 지질에 대한 가수분해 효소인 esterase 및 esterase lipase에 대한 활성이 우수하였다. 용혈여부를 확인한 결과, 분리균 모두 용혈반응이 나타나지 않았다. 또한 용혈을 일으키는 다제내성 균주에 대한 항용혈 효능을 검토한 결과, S. aureus CCARM 3855에 대한 항용혈 효능은 BMSE-HMP002가 75.71 ± 10.00%로 가장 높았으며, E. coli DC 2 CCARM 0238과 P. aeruginosa CCARM 0223에 대한 항용혈 효능은 BMSEHMP001이 각각 76.92 ± 2.99%와 87.93 ± 1.93%로 가장 높게 나타났다. 다제내성균 Staphylococcus spp., Escherichia spp., Pseudomonas spp., Salmonella spp., Klebsiella spp. 및 Enterobacter spp.에 대한 항균활성을 검토한 결과, E. faecalis BMSE-HMP 4주는 그람 양성균주와 그람 음성균주에서 모두 항균력을 보였으며, 분리균 4주 중에서는 BMSEHMP001과 BMSE-HMP002가 가장 우수한 결과를 보였다. 본 연구에서는 모유유래 유산균 E. faecalis BMSE-HMP 4주의 안전성과 다제내성 균에 의한 용혈 및 항균 효과를 검토하여 유용 유산균으로써 가능성을 확인하였으며, Enterococcus 균주는 항생제 내성 유전자 및 독성 유전자가 없는 경우에 한하여 사용이 가능한 것으로 고시된 바와 같이 본 연구에서 분리한 모유유래 유산균 E. faecalis BMSEHMP 4주의 항생제 내성 및 독성에 대한 추가적인 연구를 통해 안전성에 대한 입증이 필요할 것으로 생각된다. In this study, the hemolysis of Enterococcus faecalis BMSE-HMP strains, isolated from human breast milk, was investigated, and the anti-hemolytic and antimicrobial effects on multidrug-resistant (MDR) bacteria were investigated. The enzyme activity of E. faecalis BMSE-HMP 4 strains was measured, and it was found that the activities of esterase and esterase lipase were the highest. In addition, no hemolytic reaction was observed in any of the isolates. Subsequently, the anti-hemolytic activity against MDR strains causing hemolysis was evaluated. E. faecalis BMSE-HMP002 had the highest anti-hemolytic activity against Staphylococcus aureus CCARM 3855 at 75.71 ± 10.00%. The anti-hemolytic activity against Escherichia coli DC 2 CCARM 0238 and Pseudomonas aeruginosa CCARM 0223 showed that the activity of BMSE-HMP001 was highest at 76.92 ± 2.99% and 87.93 ± 1.93%, respectively. Examination of the antimicrobial effects against the MDR bacteria Staphylococcus spp., Escherichia spp., Pseudomonas spp., Salmonella spp., Klebsiella spp., Enterobacter spp., and E. faecalis BMSE-HMP strains showed antimicrobial effects against both gram-positive and gram-negative strains. Breastfeeding delivers enterococci into the intestinal tract of newborns by lactation, and its usefulness is attracting attention as it has been reported that enterococci have a potential effect on neonatal immune development. In this study, the hemolytic and antimicrobial effects of E. faecalis BMSE-HMP strains on MDR bacteria were investigated, to confirm their potential as useful lactic acid bacteria. Additional studies on the antibiotic resistance and toxicity of the E. faecalis BMSE-HMP strains, isolated in this study, are necessary to prove it safe for use.