• Food Science of Animal Resources
• /
• v.36 no.3
• /
• pp.427-434
• /
• 2016

Benzoic acid is occasionally used as a raw material supplement in food products and is sometimes generated during the fermentation process. In this study, the production of naturally occurring yogurt preservatives was investigated for various starter cultures and incubation temperatures, and considered food regulations. Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus reuteri, Lactobacillus plantarum, Bifidobacterium longum, Bifidobacterium lactis, Bifidobacterium bifidum, Bifidobacterium infantis, and Bifidobacterium breve were used as yogurt starter cultures in commercial starters. Among these strains, L. rhamnosus and L. paracasei showed the highest production of benzoic acid. Therefore, the use of L. rhamnosus, L. paracasei, S. thermophilus, and different incubation temperatures were examined to optimize benzoic acid production. Response surface methodology (RSM) based on a central composite design was performed for various incubation temperatures (35-44℃) and starter culture inoculum ratios (0-0.04%) in a commercial range of dairy fermentation processes. The optimum conditions were 0.04% L. rhamnosus, 0.01% L. paracasei, 0.02% S. thermophilus, and 38.12℃, and the predicted and estimated concentrations of benzoic acid were 13.31 and 13.94 mg/kg, respectively. These conditions maximized naturally occurring benzoic acid production during the yogurt fermentation process, and the observed production levels satisfied regulatory guidelines for benzoic acid in dairy products.

• Microbiology and Biotechnology Letters
• /
• v.39 no.4
• /
• pp.345-349
• /
• 2011

The bacterial growth and pH of Pleuropterus cilinervis extracts and animal milk, fermented with Lactobacillus rhamnosus during the fermentation process, were evaluated. The results indicated that the bacterial count after fermentation always remained higher than 6 log CFU/mL, with a constant pH of approximately 4. In order to evaluate the effects of Pleuropterus cilinervis extracts and animal milk, fermented with Lactobacillus rhamnosus, on hair growth promotion, C57BL/6 mice were chosen as experimental subjects. Six week old males with similar body weights were divided into four groups; a normal group (saline), a negative control group (essence base), a positive control group and an experimental group (Pleuropterus cilinervis extracts and animal milk, fermented with Lactobacillus rhamnosus, mixed with negative control). The substances and test materials were applied topically on the back skin of the mice for 8 days. Other external conditions and variables such as food intake were kept at the same as the four groups. At the end of the experiment it was noted that hair re-growth in the experimental group, using gross and histological examinations, was higher than that in the positive control group. This study therefore provides an empirical evidence that Pleuropterus cilinervis extracts and animal milk fermented with Lactobacillus rhamnosus promotes hair growth, and suggests that applications could be found in hair loss treatments.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
• /
• 2005.05a
• /
• pp.338-342
• /
• 2005

본 연구에서는 Kefir를 MRS선택배지에 도말하여 생장이 우수한 Lactobacillus sp. 최종 분리하였다. 분리된 Lactobacillus sp. 균은 API Kit의 당발효 시험과 16s RNA배열 분석으로부터 Lactobacillus rhamnosus로 동정되었다. Lactobacillus rhamnosus균주는 amylase와cellulase, xylanase 비활성이 0.673과 0.269, $0.288\;{\mu}mole/min/mg$으로 높은 활성을 보였다. 그리고, pH 2에서 65% 이상이 잔존하는 강한 pH내성과 1.0% 담즙산이 함유된 배지에서도 72% 생존하는 내담즙성을 나타냈으며, 열안정성도 비교적 뛰어난 것으로 확인되었다. 대장균에 Lactobacillus rhamnosus를 첨가하여 혼합배양시는 18시간이내에 대장균이 100% 사멸되었다. 이상의 결과로부터 분리된 Lactobacillus rhamnosus 균주는 probiotics 로서의 우수한 특성을 가진 것으로 확인되었다.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.5
• /
• pp.753-757
• /
• 2015

Recently, Lactobacillus rhamnosus GG (LGG) was shown to exert insulin-sensitizing and adiposity-reducing effects in high-fat (HF) diet-fed mice. In the present study, we observed that the effects were correlated with the extent of dysbiosis induced by HF diet feeding before LGG administration. LGG-treated mice were protected from HF diet-induced adiposity and/or insulin resistance when LGG was treated after, not along with, HF diet feeding. Results indicate that, under HF dietary condition, supplemented LGG reverses insulin resistance, but does not block its onset.

• Food Science and Industry
• /
• v.44 no.1
• /
• pp.69-71
• /
• 2011

프로바이오틱스(Probiotics)는 적정량 섭취 시 장내 균총의 유지 및 균형을 맞추어 장의 항상성 유지에 도움을 주는 등 인체의 유용한 작용을 하는 균이다. 주로 유제품에 많이 포함 되어있으며 다양한 국가에서 오래 전부터 섭취되어 왔다. 특히, Lactobacillus는 가장 많이 연구된 probiotic 중 하나로 100개 이상의 종으로 구성되어 있으며, 다양한 연구를 통해 Lactobacillus는 단지 식품으로의 역할 뿐만이 아닌 장 질환에 관련한 그 작용이 밝혀져 왔다. 본 총설에서는 프로바이오틱 Lactobacillus rhamnosus GG가 여러 장질환에 미치는 영향과 Lactobacillus rhamnosus GG 포함된 발효유 '퓨어'의 섭취가 과민성 대장증후군에 미치는 효과에 대해 논의하였다.

• Microbiology and Biotechnology Letters
• /
• v.50 no.4
• /
• pp.477-487
• /
• 2022

Probiotics provide a symbiotic relationship and beneficial effects by balancing the human intestinal microbiota. The relationships between microbiota changes and various diseases may predict health abnormalities and diseases. Treatment with vitamins and probiotics is one therapeutic approach. To evaluate the effect of probiotics on vitamin absorption, we chose Lactobacillus rhamnosus CBT-LR5 treatment, which has resistance to vitamin C-inducible toxicity, with vitamins in high-fat diet (HFD)-induced obesity models. CBT-LR5 affected the absorption of micronutrients, such as ionic minerals and water-soluble vitamins. An increase in vitamin C absorption by CBT-LR5 enhanced the antioxidant response in HFD-induced obesity models. Increased vitamin B absorption by CBT-LR5 regulated lipid metabolism in HFD-induced obesity models. These favorable effects of CBT-LR5 on the absorption of vitamins should be investigated as candidate therapeutic target treatments for metabolic diseases.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.38 no.2
• /
• pp.155-160
• /
• 2011

Probiotics has currently attracted for means of preventive treatment measurement instead of using non-specific and broad spectrum antimicrobials. In previous studies, two main probiotics species, Lactobacillus and Bifidobateria, showed the reduction of DMFS and S. mutans counts. However, the timing of introducing probiotic species to oral cavity is not clear. The aim of this study is to evaluate the changes of binding ability of S. mutans in various concentrations and inoculation time of L. rhamnosus GG. Adding the following concentration of L. rhamnosus GG, $1{\times}10^6$ CFU, $1{\times}10^7$ CFU and $1{\times}10^8$ CFU, to S. mutans medium demonstrates significant reduction of S. mutans counts. Additionally, more reduction was observed when L. rhamnosus were inoculated prior to S. mutans or simultaneously inoculated compared to when S. mutans were inoculated prior to L. rhamnosus after 3 hours of incubation. Based on this research, the timing of introducing probiotics should be considered when probiotics are utilized as a preventive treatment measurement.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.6
• /
• pp.939-945
• /
• 2006

The physiological characteristics and function of the exopolysaccharide (EPS) produced by Lactobacillus rhamnosus ATCC 9595 were determined. The total quantity of EPS was rapidly increased to 496$\pm$20 mg/l during the exponential phase, and then maintained steadily during the stationary phase. During the exponential phase (18 h), the total EPS consisted of 61% cell-bound EPS (cb-EPS) and 39% released EPS (r-EPS), whereas the relative proportion of EPS during the stationary phase (48 h) was convered to 23% cb-EPS and 77% r-EPS. On gel permeation chromatography, cb-EPS was fractionated as a single peak of 8.6$\times10^6$ Da, whereas r-EPS was fractionated as two peaks with average molecular weights of 4.3$\times$10$^4$ and 8.6$\times10^6$ Da. Interestingly, both EPS species exhibited anticancer properties and cholera toxin-binding activities. Our results suggest that the EPS generated by L. rhamnosus ATCC 9595 might be suitable for use as a functional food or food supplement.

• Microbiology and Biotechnology Letters
• /
• v.46 no.2
• /
• pp.91-101
• /
• 2018

The aim of this study was to transfer the 18.5 kb gene clusters coding for 17 genes from Lactobacillus rhamnosus to Lactococcus lactis subsp. cremoris MG1363 in order to determine the effect of host on exopolysaccharide (EPS) production and to provide a model for studying the phosphorylation of proteins which are proposed to be involved in EPS polymerization. Lactobacillus rhamnosus RW-9595M and ATCC 9595 have 99% identical operons coding for EPS biosynthesis, produced different amounts of EPS (543 vs 108 mg/l). L. lactis subsp. cremoris MG1363 transformed with the operons from RW-9595M and ATCC 9595 respectively, produced 326 and 302 mg/l EPS in M17 containing 0.5% glucose. The tyrosine protein kinase transmembrane modulator (Wzd) was proposed to participate in regulating chain elongation of EPS polymers by interacting with the tyrosine protein kinase Wze. While Wzd was found in phosphorylated form in the presence of the phosphorylated kinase (Wze), no phosphorylated proteins were detected when all nine tyrosines of Wzd were mutated to phenylalanine. Lactococcus lactis subsp. cremoris could produce higher amounts of EPS than other EPS-producing lactococci when expressing genes from L. rhamnosus. Phosphorylated Wzd was essential for the phosphorylation of Wze when expressed in vivo.

• Journal of Microbiology and Biotechnology
• /
• v.33 no.7
• /
• pp.915-925
• /
• 2023

Sarcopenia is defined as loss of muscle mass and strength due to aging. Recent studies show that sarcopenia may improve via the gut-muscle axis, suggesting that gut health may affect muscle phenotypes. In this study, we aimed to investigate the ability of Lactobacillus rhamnosus JY02 as a probiotic strain isolated from kimchi to alleviate sarcopenia. L. rhamnosus JY02-conditioned medium (CM) reduced dexamethasone (DEX)-induced myotube diameter atrophy and expression of muscle degradation markers (MuRF1 and atrogin-1) in C2C12 cells. The amelioration of sarcopenia was investigated by measuring body composition (lean mass), hand grip strength, myofibril size (using histological analysis), and mRNA and protein expression of muscle-related factors in a DEX-induced mouse model. The results of these analyses showed that L. rhamnosus JY02 supplementation promoted the production of muscle-enhancement markers (MHC Iβ, MHC IIα, and Myo-D) and reduced both the production of muscle degradation markers and the symptoms of muscle atrophy (loss of lean mass and muscle strength). We also found decreased levels of pro-inflammatory cytokines (IL-6, IFN- γ) and increased levels of anti-inflammatory cytokines (IL-10) in the serum of DEX+JY02-administered mice compared to those in DEX-treated mice. Overall, these results suggest that L. rhamnosus JY02 is a potent probiotic supplement that prevents sarcopenia by suppressing muscle atrophy.