• Korean Journal of Microbiology
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• v.39 no.3
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• pp.192-196
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• 2003

To obtain large pools of lactic acid bacteria, a strain was isolated from Tongchimi. Through its sugar fermentation and analysis of 16S rRNA gene, it was identified to be Lactobacillus plantarum HB1. This strain is Gram-positive and catalase-negative. In the range of 1～88 bp in the HB1 16S rRNA gene, the HB1 strain was homologous with other L. plantarum strains by almost 100%, and in the range of the rest 32 bp, the HB1 strain showed considerable variation, compared to other strains. Nitrate which may exist in radish can be easily converted to nitrite. The nitrite interacts with amine, and becomes nitrosamine which may cause stomach cancer. The culture obtained by HB1 strain could eliminate 400 ${\mu}M$ nitrite within 1.5 hr. It is necessary to isolate specific components which are involved in nitrite elimination in the culture and to study on its mechanism.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.436-441
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• 2018

Ginseng are native traditional herbs, which exhibit excellent pharmacological activities. Probiotic Lactobacillus helveticus KII13 and Pediococcus pentosaceus strain KID7 were used for ginsenoside transformation by fermenting crude ginseng extract to enhance minor gisenoside content. Thin-layer chromatography (TLC) analysis of fermented ginseng extract showed that the minor ginsenosides Rg3, Rh1, and Rh2 were main products after 5 days of fermentation. HPLC analysis was performed to quantify the major and minor ginsenosides. The Rg3 peak appeared on the 3rd day while the appearance of Rh2 peak and Rh1 peak were observed on the 5th day. The co-culture of L. helveticus KII13 and P. pentosaceus KID7 converted major ginsenosides (Rb1 and Rg1) into minor ginsenosides (Rg3, Rh2, and Rh1).

• Food Science and Preservation
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• v.5 no.1
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• pp.49-56
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• 1998

The effects of the water extracts from thyme(TM) and tarragon(TG) on shelf-life and quality of kimchi were investigated by measuring the changes in pH, acidity, number of total microorganisms, number of Lactobacillii and Leuconostoc during fermentation at 1$0^{\circ}C$, and were tested for antimicrobial activities against Lactobacillus plantarum and Leuconostoc mesenteroides. TM and TG were extracted with water, ethyl ether, ethyl acetate and ethanol. Water, ethyl ether, ethyl acetate and ethanol extracts of TM showed antimicrobial activities against Lactobacillus plantarum and did not observed against Leuconostoc mesenteroides. On the other hand, water, ethyl acetate and ethanol extracts of TG showed antimicrobial activities against Leuconostoc mesenteroides and did not observed against Lactobacillus plantarum. The decrease of pH and the increase of acidity showed lower in kimchi prepared by adding water extracts from TM than in products from TG. The number of total microorganisms were also detected less in the kimchi prepared by adding water extracts from TM. And, the properties of barkless of kimchi measured instrumentally were higher for kimchi prepared by adding water extracts from TM, also maintaining good crispness. The optimal addition amounts of both TM and TG for good overall and spicy taste of kimchi were 0.03%. The results suggested the possible use of the extracts of TM and TG can be successfully used for the quality and extension of shelf-life of kimchi.

• KSBB Journal
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• v.29 no.3
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• pp.210-219
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• 2014

Sayuksan has been widely applied to treat a variety of diseases such as acute hepatitis, gastritis, and colitis. Sayuksan consists of medicinal herbs such as Glycrrhizae uralensis Fischer, Paeonia lactiflora Pallas, Bupleurum falcatum Linne, and Poncirus trifoliata Rafinesqul. Methanol extracts (1 mg/mL) from the four kinds of medicinal herbs did not show antibiotic activities against general test strains and multi-drug resistant strains. The antibacterial activity of fermented medicinal herbs extracts with Lactobacillus spp. strain was confirmed as Gram-positive bacteria which are higher than Gram-negative bacteria. Extracts of Glycrrhizae uralensis Fischer fermented with Lb. casei KCTC 3109 displayed inhibitory diameters of 16 mm against Pseudomonas aeruginosa P01828. Superoxide dismutase (SOD)-like activity of the medicinal herb extracts was not determined, but the extract of Paeonia lactiflora Pallas fermented with six strains of Lactobacillus spp. had the highest antioxidant activity. SOD-like activity of Paeonia lactiflora Pallas extracts fermented by Lb. brevis KCTC 3498 was $41.4{\pm}0.8%$, which was the highest antioxidant activity among the fermented extracts with the other medicinal herbs.

• The Journal of Internal Korean Medicine
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• v.34 no.2
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• pp.155-164
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• 2013

Objectives : This study aimed to evaluate the single oral dose toxicity of Jaeumganghwa-tang (Ziyinjianghuo-tang) and Jaeumganghwa-tang (Ziyinjianghuo-tang) fermented with Lactobacillus acidophyllus in male and female ICR mice. Methods : In this single oral toxicity study, non-fermented and fermented Jaeumganghwa-tang (Ziyinjianghuo-tang) were administered to male and female ICR mice as an oral dose of 500, 1000 and 2000 mg/kg. After single administration, body weight changes, general behavior, adverse effects and mortality were determined for 14 days. Serum chemistry, organ weights and necropsy findings were evaluated at the end of the experiment. Results : There were no mortality or signs of toxicity for 14 days. There were also no significant differences in body weights, organ weights, or serum chemistry values between treatment and control groups. Conclusions : These results indicate that the 50% lethal dose of Jaeumganghwa-tang (Ziyinjianghuo-tang) fermented with Lactobacillus acipophullus may be over 2000 mg/kg. This finding can be expected to provide scientific evidence for the safety of Jaeumganghwa-tang (Ziyinjianghuo-tang) fermented with Lactobacillus acidophyllus.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.801-806
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• 2002

A multiplex competitive polymerase chain reaction (PCR) method was developed for the rapid identification and quantification of Leuconostoc mesnteroides and Lactobacillus plantarum populations which are the key microorganisms in kimchi fermentation. The strain-specific primers were designed to selectively amplify the target genes encoding 165 rRNA of L. plantarum and dextransucrase of L. mesenteroides. There was a linear relationship between the band intensity of PCR products and the number of colony forming units of each model organism. The PCR quantification method was compared with a traditional plate-counting method f3r the enumeration of the two lactic acid bacteria in a mixed suspension culture and also applied to a real food system, namely, watery kimchi. The population dynamics of the two model organisms in the mixed culture were reliably predictable by the competitive PCR analysis.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1160-1167
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• 2018

The objective of this study was to evaluate the composition, pH, titratable activity, microbial properties, and antioxidant effect of yogurt using ginseng extract powder (GEP), Lactobacillus plantarum NK181, and Streptococcus thermophilus as the starter culture. Different concentration of GEP (0%, 0.5%, 1%, 1.5%, and 2% (w/v)) were used in the yogurt. During yogurt fermentation, pH was decreased; however, titratable acidity and viable cell counts were increased. The addition of GEP to yogurt led to a decrease in moisture content and an increase in the fat, ash, and total solids content. The antioxidant effect using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, ${\beta}$-carotene bleaching, and ferric reducing antioxidant power (FRAP) assay gradually increased with added GEP. Overall, yogurt fermented with 1% GEP was acceptable in terms of cell viability and antioxidant effect. These results might provide information regarding development of ginseng dairy products with enhanced antioxidant activities and probiotic properties.

• Microbiology and Biotechnology Letters
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• v.51 no.1
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• pp.18-25
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• 2023

After random mutagenesis, the mutant Lactobacillus plantarum GNS300 showed improved exopolysaccharide production as determined by the quantification of total sugar. The mutant L. plantarum GNS300 produced 2.82 g/l of exopolysaccharide which showed 79.62% improved exopolysaccharide production compared with the parental strain. When exopolysaccharide of L. plantarum GNS300 was analyzed, the exopolysaccharide is composed of galactose (93.35%) and glucose (6.65%). Through the optimization of fermentation conditions using a bioreactor, 2.93 g/l of exopolysaccharide was produced from 20 g/l of glucose at 35℃, 500 rpm, and 0.1 vvm for 12 h. The mutant L. plantarum GNS300 exhibited 69.18% higher antioxidant activity than that from the parental strain, which might be caused by higher exopolysaccharide production. The concentrated supernatant of the mutant L. plantarum GNS300 inhibited the growth of gram-positive bacteria (Bacillus cereus and Staphylococcus aureus) and gram-negative bacteria (Escherichia coli, Vibrio parahaemolyticus, and Salmonella typhimurium).

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.181-185
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• 2005

We investigated the fermentative production of lactic acid from cheese whey and corn steep liquor as cheap raw materials using Lactobacillus sp. RKY2 to reduce the manufacturing cost of lactic acid. Lactic acid yields were obtained at more than 0.98 g/g from medium containing whey lactose. Lactic aid productivities and yields obtained from whey lactose were slightly higher than those obtained from pure lactose. The final concentration of lactic acid increased with increase, in whey lactose concentration, whereas the lactic acid productivity decreased probably due to substrate inhibition. The fermentation efficiencies were improved by addition of more corn steep liquor to the medium.

• Microbiology and Biotechnology Letters
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• v.25 no.6
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• pp.617-622
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• 1997

This studies were carried out to investigate the physiological characteristics of lactic acid bacteria related to kimchi fermentation. 157 strains of lactic acid bacteria were isolated from home-made kimchi of Taegu district. 144 strains of isolated lactic bacteria showed resistance to artifical gastric juice and bile. Among isolated strains, fifteen strains were selected according to the growth characteristics. The selected strains survived for 24 hours in artifical bile after incubation for 3 hours in artificial gastric jucie (pH 2.5). Especially, three strains such as B-10, K-2, and F-3, showed little viable cell change for 3 hrs incubation in artifical gastric juice. The selected strains showed low viability in artificial gastric juice but high in artifical bile. The selected strains also showed significantly antimicrobial activities to pathogens such as Listeria monocytogenes, Escherichia coli, Bacillus subtili, Staphylococcus aureus and Vibrio parahaemolyticus. The fifteen selected strains were identified as Lactobacillus plantarum, Lactobacillus sake and Leuconostoc mesenteroides.