• The Korean Journal of Food And Nutrition
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• v.12 no.1
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• pp.69-76
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• 1999

In order to screen lactic acid bacterial starter having high antibacterial activity and giving good flavor in Dongchmi for Naengmyon antibacterial activity and acid producing ability of 24 strains of Kimchi lactic acid bacteria were tested. Among 24 strains tested Leuconostoc mesenteroides subsp. mesenteroides C16, Leu. paramesenteroides C18 Lactobacillus bavaricus B01, B06, C19, C32 Lac. homohiochii B21 and B22 showed high antibacterial activity and their antibacterial activities were more active against Listeria monocytogenes and Staphylococcus aureus than against Escherichia coli and Salmonella typhimurium. The odors of Dongchimi-juices fermented with Leu. mesenteroides or Leu. paramesenteroides were more favorable than those with Lac. bavaricus or Lac. homohiochii. But the odors of Naengmyon-broths which were made with each Dongchimi-juice were not significantly different each other. In consideration of antibacterial ac-tivity and flavor of Dongchimi-juice two strains of lactic acid bacteria Lac. homohiochii B21 and Leu. mes-enteroides subsp. mesenteroides C16 were finally screened out as Dongchimi starters.

• KSBB Journal
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• v.17 no.2
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• pp.137-141
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• 2002

Levan oligosaccoharides and low molecular weight levin were produced from levin by acid hydrolysis and following column chromatography. Levan hydrolysis was progressed proportionally as increased incubation time. In terms of levan hydrolysis reaction, no differences were found from the sources of levan. Optimum hydrolysis conditions for the formation of levan oligosaccharides were, 0.38 M H$_2$S0$_4$; and incubation at 95$\^{C}$ for 4 min. The purified products were determined as the mixture of oligosaccharides (degree of polymerization (DP) of 3-6), Two of lactic acid-producing bacteria, Lactobacillus plantarum KCTC 3104 and Pediococcus pentosaceus KCTC 3507, were studied in vitro for their ability to metabolize levin oligosaccharides. Apparently, the growth of both cells were increased by levin oligosaccharide diet, compared with those of levan diets, suggesting that levan oligosaccharides may be beneficial in selectively growth of lactic acid-producing bacteria.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.231-235
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• 1988

Population changes of aerobic bacteria, yeasts, and lactic acid bacteria ware investigated during the fermentation of Kimchis containing 0, 1, 2, 4, and 6% garlic at $21^{\circ}C$. The numbers of aerobic bacteria increased during the first 2 days and decreased thereafter. The higher the garlic concentration of the Kimchis was, the smaller the increase of the aerobic bacterial population was during the initial periods of the fermentations. Garlic concentrations that showed the largest population difference between them after 2-days fermentation were 1% and 2%. The population of lactic acid bacteria also increased only during the first 2 days and was held thereafter. Lactic acid bacterial population increased more at higher garlic concentrations during the initial period of the fermentations and major microorganisms contributed to the increase were Lactobacillus brevis and low acid-producing lactbacilli. Changes of yeasts at the different garlic concentrations during the fermentations were not apparent.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.227-232
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• 2014

In this study, Gluconacetobacter sp. gel_SEA623-2 isolated from citrus that produces bacterial cellulose was used to examine the effect of initial concentration of acetic acid and mixed culture inoculated with Lactobacillus plantarum KCCM 80077 on productivity of bacterial cellulose. In mixed culture added with 0.5% acetic acid, the viable cell count increased from $2.4{\times}10^6CFU/ml$ to $1.1{\times}10^7CFU/ml$ after 14 days of culture, and total acidity was about 0.3% higher than single culture added with 0.5% acetic acid, which implies that additional lactic acid was produced by L. plantarum KCCM 80077. In single culture, although bacterial cellulose productivity was higher when the initial concentrations of acetic acid were 0.0% and 0.5%, than when it was 1.0%, there was no significant difference. However, in mixed culture, adding 0.5% acetic acid resulted in dry weight of $37.83{\pm}6.81g/L$ and thickness of $10.33{\pm}0.58mm$, showing a significant difference from that of single culture added with 1% acetic acid, $28.40{\pm}1.23g/L$ and $7.50{\pm}0.50mm$ (P<0.05).

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.119-127
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• 2013

Twenty-three strains of Leuconostoc species and 45 strains of Weissella species inhibiting the growth of Lactobacillus sakei, one of the most populous lactic acid bacteria in over-ripened kimchi, were isolated from kimchi in our previous study. Among these hetero-fermentative 68 strains, Leuconostoc mesenteroides CK0128, Weissella cibaria CK0633, and W. cibaria KK0797 exhibited a relatively high survival rate in MRS medium, which was adjusted to pH 4.3 using an acid mixture consisting of acetic and lactic acids, and produced a large amount of exopolysaccharides. The culture supernatants of 3 strains were fractionated by a molecular weight cutter and lyophilized. The fractions with a molecular weight smaller than 3,000 Da showed antagonistic activity against Staphylococcus aureus and Lb. sakei. The anti-bacterial substances were very stable to heat treatments ($121^{\circ}C$, 15 min) and active at acidic conditions below pH 5. ${\alpha}$-Amylase, lipase, and proteolytic enzymes (proteinase K and pepsin) did not affect their activities. These non-proteinaceous anti-bacterial substances inhibited the growth of several food pathogens.

• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1174-1178
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• 2011

Exopolysaccharides (EPSs) are microbial polysaccharides that are released outside of the bacterial cell wall. There have been few studies on EPS-producing lactic acid bacteria that can enhance macrophage activity and the underlying signaling mechanism for cytokine expression. In the current study, EPS-overproducing Lactobacillus (L.) paracasei KB28 was isolated from kimchi and cultivated in conditioned media containing glucose, sucrose, and lactose. The whole bacterial cells were obtained with their EPS being attached, and the cytokine-inducing activities of these cells were investigated. Gas chromatography analysis showed the presence of glucose, galactose, mannose, xylose, arabinose, and rhamnose in EPS composition. EPS-producing L. paracasei KB28 induced the expression of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and IL-12 in mouse macrophages. This strain also caused the degradation of $I{\kappa}B{\alpha}$ and phosphorylation of the major MAPKs: Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK)1/2. The use of pharmacological inhibitors showed that different signaling pathways were involved in the induction of TNF-${\alpha}$, IL-6 and IL-12 by L. paracasei KB28. Our results provide information for a better understanding of the molecular mechanisms of the immunomodulatory effect of food-derived EPS-producing lactic acid bacteria.

• Journal of Microbiology and Biotechnology
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• v.24 no.5
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• pp.648-660
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• 2014

Doenjang, a traditional Korean fermented soybean paste, is made by mixing and ripening meju with high salt brine (approximately 18%). Meju is a naturally fermented soybean block prepared by soaking, steaming, and molding soybean. To understand living bacterial community migration and the roles of bacteria in the manufacturing process of doenjang, the diversity of culturable bacteria in meju and doenjang was examined using media supplemented with NaCl, and some physiological activities of predominant isolates were determined. Bacilli were the major bacteria involved throughout the entire manufacturing process from meju to doenjang; some of these bacteria might be present as spores during the doenjang ripening process. Bacillus siamensis was the most populous species of the genus, and Bacillus licheniformis exhibited sufficient salt tolerance to maintain its growth during doenjang ripening. Enterococcus faecalis and Enterococcus faecium, the major lactic acid bacteria (LAB) identified in this study, did not continue to grow under high NaCl conditions in doenjang. Enterococci and certain species of coagulase-negative staphylococci (CNS) were the predominant acid-producing bacteria in meju fermentation, whereas Tetragenococcus halophilus and CNS were the major acid-producing bacteria in doenjang fermentation. We conclude that bacilli, LAB, and CNS may be the major bacterial groups involved in meju fermentation and that these bacterial communities undergo a shift toward salt-tolerant bacilli, CNS, and T. halophilus during the doenjang fermentation process.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1646-1652
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• 2002

Si-Raw is a raw cured meat (raw, cured meat fermented with steamed rice) produced by the aboriginal people of Taiwan. In order to prevent food poisoning or intoxication from botulism, new methods of monitoring the production base on hurdle technology were investigated. New methods investigated incorporated citric acid, sodium hypophosphite, Monascus anka mash, plum paste or lactic acid bacteria inoculum added separately to meat with steamed rice and salt to lower the Aw (water activity) and pH values of the products to control the microbial growth. Results showed that anaerobic bacterial counts, lactic acid bacterial counts and aerobic bacterial counts for the products of all treatments were less than $10^6$, $10^5$ and $10^2cfu/g$, respectively. Sodium chloride content of all products was above 5.46%, water activity was below 0.939 and pH value was below 4.27. IMP was lower and ATP and hypoxanthine were higher. ATP concentrations were higher in the samples which contained the anka mash. Result of sensory panel test indicated that most people preferred the products with added sodium hypophosphite. Except for the fact that the content of tryptamine in the sample with Monascus anka mash was higher, the amine concentrations for all treatments were lower than those of other fermented meat products. The amino acid nitrogen content was higher in the product made from raw meat treated with citric acid, but lower in the other products. Neither Clostridium botulinum nor Trichinella spiralis were detected in any of the treatments. The result may indicate that hurdle technology is effective for hygiene and safe producing Si-Raw.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.550-556
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• 1994

For an extension of the palatable stage in Kimchi which was limited by further lowering pH as the fermentation proceeds, the starter culture of bacteriocin-producing Enterococcus faecium DU 0267 obtained from Kimchi was added at the preparation time, and pH, bacteriocin activity, growth of lactic acid bacterial group and gas production in Kimchi were examined during the fermentation at 10, 20 and 30$\circ$C . The pH of Kimchi fell rapidly to 4.0~4.2 in the early fermentation stage, and then, has gone down very slowly throughout further fermentation. The lactic acid bacte- ria, particularly lactobacilli and leuconostoc, were remarkably slower in its growth than those in the control. Although the patterns of these change during fermentation at different temperatures were similar, these effects by the addition of starter were enhanced at 10 and 20$\circ$C. The bacteriocin activity was increased rapidly during log phase of the bacteriocin producer strain in the early fermentation stage of Kimchi and reached their maximum after fermentation at 10$\circC, for 8 days and at 20 or 30$\circ$C for 2 days. Thereafter, the activity disappeared quickly. The gas production by fermentation was also suppressed considerably, and their volume produced after fermentation at 20$\circ$C for 14 days corresponded to 60% of those of the control.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.365-365
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• 2017

Yogurt is a food produced by bacterial fermentation of milk and the bacteria used to make it are known as "yogurt cultures". Most of them belong to probiotics such as Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. Domestic fermented milk market is increasing and about 30 companies are producing yogurt. The purpose of this study was to analyze the quality characteristics of domestic commercial semisolid type yogurt. We collected 20 types of commercial yogurt at local markets. Physicochemical properties including pH, sugar content, acidity, viscosity and microbial characteristics of lactic acid bacteria counts were measured. The yogurt showed pH 4.5, 7.4~18.1% of sugar contents, 0.6~1.3% of total acids and 282~748 cP of viscosities. In the microorganism populations, lactic acid bacteria count were 6.5~11.5 Log CFU/mL and anaerobic lactic acid bacteria count were 7.2 ~ 11.1 Log CFU/mL. The quality characteristics were different depending on the constituents of the sample and the microorganisms used. These results are related to the quality characteristics of yogurts which are useful information about identifying new trends in domestic fermented milk industry.