• 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.

• Korean Journal of Veterinary Service
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• v.36 no.4
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• pp.297-301
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• 2013

The present study was to investigate anti-microbial effects of curcumin on major bacterial pathogens for farmed fish, such as Aeromonas hydrophila, A. salmonicida subsp. masoucida, A. salmonicida subsp. salmonicida, Edwardsiella tarda, Vibrio vulnificus, V. paraheamolyticus using disk diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests. In disc diffusion test, curcumin exhibited concentration-dependent antimicrobial activities to all bacteria pathogens used in the study. Antimicrobial effects of curcumin was found differently depending on bacterial species when determined by MIC or MBC tests. For examples, E. tarda and A. hydrophila was respectively the most sensitive bacterium for bacteriostatic and bacteriocidal effect of curcumin. Collectively, curcumin could be a potential natural drug for controlling pathogenic bacteria in the aquaculture industry.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.334-344
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• 2014

The objective of this study was to evaluate the microbiological and physicochemical characteristics, and the antagonistic activity against Helicobacter pylori ATCC 43504, of yogurt fermented with the lactic acid bacteria from Baikkimchi kept under cold storage. The viable cell counts, titratable acidity, viscosity, and total solid content of the yogurt were different according to the bacterial strains used for fermentation. There was no significant change (P>0.05) in the various properties of refrigerated yogurt. Among the tested strains, the strongest resistance against artificial gastric juice and bile salt was found for Lactobacillus brevis BK11 and Lactobacillus paracasei BK57. Due to high lactic acid levels obtained from these two lactic acid bacteria, yogurt may show good anti-Helicobacter effects according to the time-kill assay. In particular, yogurt fermented with L. brevis BK11 significantly reduced the number of H. pylori adhering to gastric epithelial AGS cells and the urease activity of this pathogen (P<0.05).

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.103-103
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• 2019

Glycyrrhizae radix, commonly known as licorice, is a perennial herb belonging to Leguminosae and also includes various components such as, glycyrrhizin, liquiritin, liquiritigenin and isoliquiritigenin etc. Licorice has been widely used in East Asia as a medicine having pharmacological effects like antioxidants, anti-bacterial, anti-inflammatory, anti-cancer and immune modulatory activities. Among various licorice, Glycyrrhiza (G.) uralensis G. glabra and G. inflata are used for pharmaceutical purposes in Korea. However, cultivation of licorice has some problems such as low quality, low productivity, and early leaf drop. Korea Rural Development Administration developed new cultivars Wongam and Sinwongam, which are improved in cultivation and quality. To register the newly developed cultivar (s) on Ministry of Food and Drug Safety in Korea as a medicine, it is necessary to prove the similarity and difference through the comparative studies between already-registered species and new cultivars. Some fungi and bacteria usually in the human oral cavity and intestines exist as harmless state in human body. Also, the skin and genital infections by fungi can lead to toxic systemic infections and are accompanied by flushing, rashes, burning or painful sensation. The influences of licorice varieties on fungi and bacteria might be an evidence to prove the outstanding effect of newly developed licorice variety. In this study, the antifungal and antibacterial activity was investigated using newly developed licorice varieties Wongam, and Sinwongam against various fungi and bacteria. These results means newly developed licorice could be used as a replacement of already-registered species in terms of antifungal and antibacterial application.

• Textile Coloration and Finishing
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• v.23 no.3
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• pp.187-194
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• 2011

This study used Jeju scoria to dye cotton fabric and measured its dyeability, colorfastness, antibacterial activity, deodorization efficiency, ultraviolet protection, and far-infrared emission. The cotton fabric was colored to yellowish red and optimal dyeing can be achieved at a temperature of $80^{\circ}C$ for a dyeing time of 120 minutes with a colorant concentration of 25%(o.w.b). The colorfastness to light, rubbing, perspiration, and washing was 8, 5, 5, and 4~5 ratings respectively, where the wash colorfastness remained after 15 wash cycles. The cotton fabric dyed with Jeju scoria demonstrated excellent antimicrobial activity to Staphylococcus aureus and high deodorization efficiency. Ultraviolet protection factor was as high as 50+. The Jeju scoria can be used as a new colorant for the natural dyeing of silk.

• KSBB Journal
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• v.31 no.4
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• pp.214-218
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• 2016

Serratia marcescens characterized by the ability to produce red pigments inhabits various ecological niches. A strain Serratia marcescens PYU was isolated from abalone (Haliotis discus) collected at the West Sea in Korea. The isolated strain was gram-negative, motile, rods like coccus, oxidase-negative, and catalase-positive; and formed red pigment. S. marcescens PYU was grown in the presence of 0~10% (w/v) NaCl, at pH 4~9, and at $10{\sim}40^{\circ}C$. The strain PYU produced red pigment, and the extracted pigment showed antibacterial activity against Streptococcus iniae and Lactococcus garviae which has been known as an important fish pathogens. Further studies are underway to elucidate the direct relationship between the red pigment and antibacterial activity.

• Journal of Dairy Science and Biotechnology
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• v.41 no.3
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• pp.126-137
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• 2023

In this study, we isolated lactic acid bacteria from Allium wakegi and examined the usability of culture supernatants obtained from these lactic acid bacteria. The antibacterial activity of the culture supernatant obtained from the isolated lactic acid bacteria against the pathogens Escherichia and Salmonella spp. was measured. The obtained lactic acid bacteria culture medium showed significant antibacterial activity against pathogenic bacteria in a dose-dependent manner. The effects of pH and heat denaturation on the observed anti-pathogenic bacterial activity was also investigated. Adjusting the culture supernatant to pH 7 resulted in loss of all antibacterial activity against pathogenic bacteria, suggesting that the antibacterial activity of the obtained culture supernatant against pathogenic bacteria is influenced by organic acids. Assessment of the heat stability of the anti-pathogenic bacterial activity revealed that heat treatment did not diminish activity. The obtained lactic acid bacteria culture medium is thus stable against heat.

• YAKHAK HOEJI
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• v.49 no.3
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• pp.237-243
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• 2005

Present study was performed for the development of a new supplementary product with gastroprotective effect. The preliminary screening were conducted for the effects of HCl-ethanol-induced gastric lesions in rats. Samples were aloe gel, active hexose correlated compound (AHCC) mentioned that have GI protective property and pulmuone healthy aloe gel (PHAG) that mixture of natural products from Pulmuone company. Aloe gel significantly inhibited HCl-ethanol-induced gastric lesions at the oral dose of 5 ml/kg. AHCC showed the strongest effectiveness at the oral dose of 1,200 mg/kg. PHAG also showed the significant effects at the oral dose of 10, 20 g/kg. In pylorus ligated rats, the treatments of aloe gel, AHCC and PHAG showed decrease in the volume of gastric secretion and acid output. And aloe gel, AHCC and PHAG significantly suppressed the aspirin-induced ulcer and chronic ulcer in pylorus ligated rats. The treatments of aloe gel and PHAG significantly reduced acetic acid-induced ulcer at the oral dose of 5 ml/kg and 10 g/kg for 12 days. In this study; we have found that PHAG had significant improvement in acute gastritis and ulcer at the dose of 20 g/kg and in chronic gastritis and ulcer at the dose of 10 g/kg. Also we evaluated the anti-bacterial activity against H. pylori treated with aloe gel, AHCC and PHAG. PHAG had a equivalent anti bacterial activity with ampicillin against H. pylori at the dose of 1 g/kg.

• Journal of Life Science
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• v.20 no.4
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• pp.578-583
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• 2010

It has been reported that extracts of globe thistle (Echinops spp.) and thistle (Circium spp., Carduus spp. and Onopordum spp.) have anti-bacterial and anti-fungal activities. Methanol extracts of Echinops setifer and Carduus spp. were used to test and see if the extracts of these plants could suppress growth of Mycobacterium smegmatis and Mycobacterium fortuitum. Although extract of Echinops setifer showed no anti-mycobacterial activities, extract of Carduus spp. showed inhibition zones when tested with filter discs. Genomic DNA was isolated from Carduus spp. and PCR was performed to clone a DNA fragment containing ITS1, 5.8S rRNA gene and ITS2. A 733-bp PCR product was obtained and its DNA sequence was reported to the GenBank (accession number GU188570). BLAST search of the obtained DNA sequence did not show a match with any DNA sequences in the Genbank. Carduus crispus and Carduus defloratus had the closest phylogenetic relationships to this plant.

• Food Science of Animal Resources
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• v.31 no.4
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• pp.609-616
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• 2011

In this study, a LCH1227 bacterial strain that possesses anti-listerial activity was isolated from fermented food and identified as Lactobacillus salivarius LCH1227 based on its morphological and biochemical properties, as well as its 16S rRNA gene sequences. Anti-listerial substance also inhibited the growth of various Gram-positive bacteria, such as vancomycinresistant Enterococcus faecalis, Streptococcus agalactiae, Bacillus cereus, Lactobacillus fermentum. The highest level of production of antimicrobial substances from L. salivarius LCH1227 occurred during the early stationary phase. The antilisterial activity was found to be stable over a broad range of pH values (2.0-12.0) and after heat treatment. However, it was inactivated by proteolytic enzymes, indicating its proteinaceous nature. The apparent molecular mass of the partially purified anti-listerial substance, as measured by Tricine-SDS-PAGE, was approximately 5 kDa.