This study investigated the effect of Lactiplantibacillus plantarum JSA22-fermented rice drinks on dextran sodium sulfate (DSS)-induced colitis in mice. Twenty-four mice were randomly assigned; No colitis (Con), colitis with tap water (DSS-only), colitis with unfermented rice (DSS-UFR), and colitis with fermented rice (DSS-FR). After inducing colitis with 2% DSS for 5 days, they were given Tap water, UFR drink, or FR drink for an additional 6 days. The DSS-FR group had significantly lower Disease Activity Index (DAI) scores compared to the DSS-only group, but no significant difference with the DSS-UFR group. Colon length was reduced in the DSS-only group. The DSS-only group had significantly higher IL-6 mRNA levels compared to the Con group, while the DSS-FR groups showed significantly lower IL-6 mRNA levels compared to the DSS-only group. These results suggest that rice drinks fermented with Lactiplantibacillus Plantarum JSA22 ameliorate the severity of DSS-colitis, by potentially reducing proinflammatory cytokines.

In probiotics production, lactic acid bacteria (LAB) are cultured on a large scale to achieve efficient processing through fermentation optimization and scale-up. In this Current study, the LAB strain Lactiplantibacillus plantarum WiKim0125 was isolated from kimchi and optimized the production. The optimization strategy for cultivating L. plantarum WiKim0125 consisted of investigating media components, selecting physiochemical conditions to enhance productivity, and scaling up for pilot-scale production. Each process condition was evaluated based on substrate consumption, lactic acid production, and viable cell yield. As a result, the final viable cell and lactic acid yield of L. plantarum WiKim0125 increased by 38.6% and 19.4%, respectively. This study provides an overview of fermentation optimization and scale-up processes for the industrial application of L. plantarum WiKim0125.

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.

The aim of this study was to evaluate the probiotic properties of lactic acid bacteria (LAB) isolated from kimchi and antioxidant and anti-inflammatory activities of heat-killed LAB strains. Regarding probiotic properties, Lactiplantibacillus plantarum SMF398 and L. plantarum SMF470 isolated from kimchi can survive under artificial gastric condition and adhere strongly to HT-29 cells. The SMF398 and SMF470 strains showed strong antimicrobial activity and co-aggregation against pathogenic bacteria. The heat-killed cells of LAB (1 mg/mL) were prepared by heating at 121℃ for 15 min. MTT assay revealed that the heat-killed cells (1 mg/mL) of SMF398 and SMF470 were not toxic to HT-29 cells. The heat-killed SMF398 and SMF470 showed significantly higher DPPH and ABTS radical scavenging activities as well as β- carotene bleaching inhibitory activity than the heat-killed L. plantarum ATCC14917, a control probiotic strain (p<0.05). In lipopolysaccharide-induced RAW264.7 cells, the heat-killed SMF398 and SMF470 significantly reduced the nitric oxide production by 30.92% and 22.81%, respectively (p<0.05). Furthermore, the heat-killed SMF398 and SMF470 significantly decreased the gene expression levels of tumor necrosis factor-α, interleukin-6, inducible nitric oxide synthase, cyclooxygenase-2 up to 58.02%, 67.70%, 53.44%, 45.90%, respectively (p<0.05). These results suggest that the heat-killed L. plantarum SMF398 and L. plantarum SMF470 might be useful as antioxidant and anti-inflammatory agents.

This study aimed to optimize the fermentation condition of black bean using probiotic lactic acid bacteria (LAB) and to evaluate characteristics and antioxidant activity of LAB fermented and heat-treated black bean. Two LAB strains were selected by analysis of acid resistance, bile resistance, antimicrobial activity, and antioxidant activity, and identified as Lactiplantibacillus plantarum CH9 and Lactiplantibacillus plantarum SU18 by 16S rRNA sequencing. Both strains showed similar or higher acid resistance, bile resistance and antimicrobial activity, compared to Lacticaseibacillus rhamnosus GG, a commercial probiotic strain. The heat-killed cells of CH9 and SU18 strains showed significantly (p<0.05) higher DPPH and ABTS radical scavenging activities than live cells. Fermentation of black bean (30%) treated with Alcalase using the two selected strains was found to be optimal condition, increasing viable cell count of LAB up to 10.8 Log CFU/g. During the fermentation, the titratable acidity of Alcalase-treated black bean was notably increased with concomitant decrease in the pH. LAB fermentation significantly (p<0.05) increased antioxidant activity based on DPPH and ABTS radical scavenging activities as well as total phenol content. In addition, total phenol content and antioxidant activity were significantly (p<0.05) enhanced by heat processing (121C, 15 min) of the fermented products. These findings are expected to be useful for the development of various LAB-fermented foods containing heat-killed probiotics.

본 연구에서는 대추 열수추출물에 대한 유산균 발효를 통해 기능성 소재로서의 가능성을 알아보고자 하여 열수추출물에 L. plantarum 을 접종하여 유산균 발효물을 제조하였으며, 열수추출물과 유산균 발효물의 영양성분 및 항산화능을 비교 ․ 분석하였다. 대추 열수추 출물에 접종한 유산균은 초기 12시간 만에 증가하였으며, 이후 72 시간까지 큰 증감없이 그 수를 유지하여 대추 열수추출물은 유산균 의 생육에 큰 영향을 미치지 않았다. 열수추출물과 유산균 발효물 의 당도, pH 및 총산도를 측정한 결과, 당도는 유산균 발효 여부와 관계없이 열수추출횟수가 증가할수록 높아졌으며, pH는 유산균 발 효 이후 현저히 감소하였고, 총산도는 2차 열수추출물의 발효물에 서만 유의적으로 증가하였다. 2차 열수추출물의 유산균 발효 여부 에 따른 일반영양성분 분석 결과, 모든 성분에서 유의적 차이를 보 이지 않았으며, DPPH 및 ABTS free radical 소거활성능은 유산 균 발효 여부에 관계없이 열수 추출횟수에 비례하여 증가하여 2차 열수추출물과 그의 발효물에서 가장 높은 결과를 나타내었다. 총폴 리페놀 함량 또한 유산균 발효여부에 관계없이 1차 열수추출물에 서 가장 높은 값이 관찰되었다. 본 연구를 통해 대추 열수추출물은 유산균 생육에 전혀 영향을 미치지 않아 유산균 발효물 제조 가능 성을 확인했으며, 또한 항산화능과 총폴리페놀 함량은 열수추출횟 수에 의해 영향을 받는다는 사실을 알 수 있었다. 하지만, 열수추출 물과 유산균 발효물 사이에 일반영양성분 및 항산화능에 큰 차이 는 없었으며, 이는 L. plantarum 단일 균주로만 연구를 진행했기 때문으로 여겨진다. 따라서 추후에 다양한 유산균주를 사용하여 대추 열수추출물의 발효를 시도해 항산화능을 비롯한 다양한 기능 성을 증가시킬 수 있는 유산균주를 탐색할 필요가 있을 것으로 사 료된다.