• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.423-428
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• 2000

Bacteriocins are classified as proteins which are produced by heterogeneous groups of bacteria, having and antimicrobial effect of the closely related organisms. Recently, bacteriocins derived from lactic acid bacteria and other food-related organisms have been the subject of much research on potential food biopreservatives. The goal of this study was to screen and characterize the bacteriocinogenic lactic acid bacteria from Jeot-gal(commercial fermented fish foods). All bacteriocinogenic isolates were identified as lactic acid bacteria. Isolates NK24, NK34, and SA72 were tentatively identified as Lactobacillus brevis, according to the API 50 CHL kit database. All antimicrobial substances produced from four lactic acid bacteria isolates completely lost their antibacterial activity after being treated with some proteases, indicating to their proteinaceous nature. The bacteriocin produced from isolates NK24, NK34, and SA72 showed a broad spectrum of activity when compared to those produced from isolate SA131. All bacteriocins isolated during the course of this study showed a bactericidal mode of inhibition.

• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.233-239
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• 2008

A new approach to the solubilization of excess activated sludge by the inoculation of lactic acid bacteria was studied to reduce the amount of sludge produced in the activated sludge treatment process. Aerobic microorganism in sludge was lysed in anaerobic condition and the cytoplasmic substance eluted was utilized as a carbon source by lactic acid bacteria. On the basis of sludge solubilization efficiency, Lactobacillus brevis and Leuconostoc mesenteroides subsp mesenteroides were selected the best candidates among five kinds of Lactobacillus sp. and seven kinds of Leuconostoc sp. The sludge solubilization efficiency by heterofermentative lactic acid bacteria was more efficient than that of homofermentative bacteria. Initial value of soluble COD (sCOD) was 1050 mg/L at the initial inoculation time increased to 3070 mg/L (192% solubilization) at 96 h of the incubation time. The inoculation of lactobacillus brevis to the sludge resulted in 2824% increase in sCOD value after 96 h of incubation than the control experiment. Leuconostoc mesenteroides subsp mesenteroides showed 152% increase of solubilization and 30% increase of S-COD/T-COD on 96 h of incubation time. Considering the increase of S-COD by the inoculation of Leuconostoc sp. on 24 h, 10% inoculation of lactic acid bacteria to the sludge was most effective.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.110-110
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• 2018

The purpose of this study was to evaluate the improved antioxidant activity of Aronia extract fermented by lactic acid bacteria isolated from fermented seafoods. Aronia fruits were collected from Sunchang, Chonbuk, South Korea. And these collected fruits were lyophilized for fermentation. For the selection of effective lactic acid bacteria useful for fermentation. Aronia fermented by lactic acid bacteria that isolated from fermented seafood was extracted with 60% ethanol. Antioxidant activity of Aronia extract was evaluated on the DPPH radical scavenging activity and total polyphenol contents were studied. To determine the optimal fermentation conditions, the changes of antioxidant efficacy was evaluated by controlling temperature (25, 30, 37, $40^{\circ}C$), Time (0~5 day) and inoculation dose of lactic acid bacteria (0.125~0.5ml). To confirm the antioxidative effect of Aronia fermented under optimal conditions, the DPPH & ABTS radical scavenging activity, total polyphenol & flavonoid contents were compared before and after fermentation were studied. 16 different kinds of lactic acid bacteria were isolated from fermented seafood, and of which antioxidant activity of Aronia fermented by Pediococcus pentosaceus B1 was maximum. Aronia fermentation at $37^{\circ}C$ was maximized when fermented for 3 days and fermentation time is decreased as the start inoculation amount of lactic acid bacteria increased. The degree of increase in antioxidant activity after Aronia fermentation is that DPPH & ABTS radical scavenging activity was increased about 27%, 20% and total polyphenols & flavonoids contents was increased about 12%, 15%. In the result of this experiment indicated that fermentation process enhances the antioxidant efficacy of Aronia.

• YAKHAK HOEJI
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• v.49 no.6
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• pp.459-464
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• 2005

The immune reinforcement of the probiotic lactic acid bacteria Lactobacillus acidophilus, Streptococcus thermophilus and Bifidobacterium bifidum was studied in RAW 264.7 cell line treated with diluted solution (dilution to $2^{5}$) of the supernatnats of lactic acid bacteria. RAW 264.7 cell line was used as a macrophage model to assess the effects of lactic acid bacteria on the production of nitric oxide (NO) and cytokine tumor necrosis factor (TNF)-$\alpha$ and cell morphological changes. The production of NO and TNF-$\alpha$ were largely affected by lactic acid bacteria in dose-dependent manner in 24 or 48 hr cultures and cell morphological changes were also largely affected by lactic acid bacteria. Especially Bifidobacterium bifidum differentially stimulated the production of NO and TNF-$\alpha$. NO production was increased by Bifidobacterium bifidum 25 $\mu$l/ml more than LPS (20 ng/ml) control, and TW-$\alpha$ by Bifidobacterium bifidum 6.25 $\mu$l/ml more than LPS (10 ng/ml) control. The in vitro approaches employed here should be useful in further characterization of the effects of lactic acid bacteria on systemic immunity.

• Food Science and Preservation
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• v.12 no.2
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• pp.184-189
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• 2005

In order to select probiotics having both a high survival rate and an ability to inhibit virulent pathogens, we have screened lactic acid bacteria and yeasts from Jeot-gal to examine their resistance to artificial gastric and bile juice. After being introduced in the artificial gastric acid for 2 hr, the isolated lactic acid bacteria and yeast were incubated for 24 hrs in the artificial bile juice. In particular, the strain ML 36, ML 128, and ML 178 survived the longest during 2 hr incubation period in the artificial gastric acid. All 3 strains of lactic acid bacteria, and 2 strains of yeast demonstrated higher growth rates than control in the artificial bile. In addition, the antimicrobial activity of lactic acid bacteria and yeasts was investigated to determine their efficiency as probiotic organisms. The lactic acid bacteria inhibited Gram positive and negative bacteria, while the yeast was marginally inhibited.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.386-389
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• 2006

Silage is a major component of cattle rations, so the improvement of silage quality by the inoculation of lactic acid bacteria is of great interest. In this study, commercially distributed Lactobacillus plantram and Lactobacillus rhamnousas NGRI 0110 were used for ensilaging of guinea grass. The four treatments used were a control silage, a silage with cellulase addition, a silage with cellulose+L. plantram addition, and a silage with cellulose + NGRI 0110 addition. Silage quality, voluntary intake, nutrient digestibility, and the characteristics of ruminal fluid of wethers were investigated. Silage to which lactic acid bacteria were added showed low pH and acetic acid concentration and the highest lactic acid content. Dry matter and organic matter digestibility were significantly (p<0.05) increased by cellulase addition and significantly (p<0.05) higher values were observed in L. plantram- and NGRI 0110-added silage. Voluntary intake of NGRI 0110-added silage was the highest and that of control silage was the lowest. We concluded that the observed ability of NGRI 0110 to tolerate low pH and to continue lactic acid fermentation in high lactic acid concentration had also occurred in actual ensilaging. The results indicate that the addition of lactic acid bacteria might improve silage quality and increase digestibility and voluntary intake. The potential for improvement by NGRI 0110 was higher than that to be gained by the use of commercially available lactic acid bacteria.

• Microbiology and Biotechnology Letters
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• v.31 no.1
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• pp.32-35
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• 2003

This study was carried out to determine the inhibitory effect of garlic juice against Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Shigella flexneri. Staphylococcus aureus, Streptococcus mutans, Virio. parahaemolyticus which are food pathogenic bacteria and Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus casei, Lactobacillus plantarum, Lactococcus. lactis, Leuconostoc mesenteroides which are lactic acid bacteria. An aqueous extract of garlic was bacteriocidal against Gram-positive and Gram-negative bacteria in all concentrations (0.1∼2.5(w/v)%) tested in this experiment. Especially 0.5(w/v)% garlic juice inactivated completely E. coli, S. typhimurium, S. flexineri, V. parahaemolyticus and 1.0(w/v)% garlic juice perfectly reduced P. aeruginosa, S. mutans. Generally, the experiment result indicate that garlic juice restrains the growth of the pathogenic bacteria better than the lactic acid bacteria. Therefore, garlic has potential for the preservation of processed foods.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.547-550
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• 2005

Fourteen out of 87 strains of lactic acid bacteria isolated tram Kimchi were found to be resistant against the action of artificial gastric and bile juices. In particular, lactobacilli KM 3, 7, 28, and 37 showed strong resistance and their viable cell counts at the initial stage remained the same even after 3 hours of cultivation in an artificial gastric juice. However, the survival rates of KM 14, 28, and 64 were found to be significantly enhanced in artificial bile juice. Based on the paper disc method, it was evident that isolated lactic acid bacteria showed antibacterial effect against Listeria monocytogenes, Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Vibrio vulnificus, and Salmonella typhimurium. The isolated lactic acid bacteria were identified as Lactobacillus plantarum and Leuconostoc mesenteroides.

• KSBB Journal
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• v.25 no.4
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• pp.311-318
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• 2010

Lactic acid bacteria display a relatively simple metabolism wherein the sugar is converted mainly to lactic acid. The extensive knowledge of metabolic pathways and the increasing information of the genes involved allows for the rerouting of natural metabolic pathways by genetic and physiological engineering. In this contribution, the lactic acid bacteria as an efficient cell factory for different (food) ingredients will be presented. The emphasis will be on some successful examples of metabolic engineering and on the physiology of these bacteria, which makes them so suitable as a cell factory.

• Journal of Dairy Science and Biotechnology
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• v.29 no.1
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• pp.55-58
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• 2011

Certain lactic acid bacteria have anti-tumor activity, especially colon cancer. The fermented milk products containing that kind of lactic acid bacteria have to be recommended for human health as excellent health functional foods. This paper have been classified by 5 regions on the functions of lactic acid bacteria related to prevention of colon cancer. 1) Enhancing of host's immune response; Production of cytokines. 2) Binding and degradation of potential carcinogens; Binding and degradation of mutagenicity. 3) The changes of intestinal microflora and production of antitumorigenic or antimutagenic compounds; Production of azoxymethane. 4) Alteration of the metabolic activity of intestinal microflora; Decrease of harmful enzymes in intestinal tract. 5) Alteration of physicochemical conditions in the colon; Decrease of pH and bile acids contents.