• Journal of the Korean Chemical Society
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• v.57 no.2
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• pp.272-278
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• 2013

Extract of ginger has been evaluated as a green inhibitor for the corrosion of steel in sulfide polluted NaCl solution using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. Potentiodynamic polarization measurements showed that this extract acts as a mixed type inhibitor but mainly inhibits the cathodic reaction. The inhibition efficiency was found to increase with inhibitor concentration reaching to approximately 83.9% using 250 ppm of ginger. Nyquist plots show a single capacitive loop in uninhibited and inhibited solutions. From EFM the causality factors are very close to theoretical values which indicate that the measured data are of good quality. The adsorption process of the studied extract on steel surface obeys Temkin adsorption isotherm. The results obtained from the different electrochemical techniques were in good agreement which prove the validity of these tools in measurement of corrosion rate. Ginger extract has no effect on Escherichia Coli and can be applied safely on waste water treatment plants.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.2
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• pp.182-187
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• 2005

This study was performed to investigate the antimicrobial effect of the Viscum album var. coloratum extracts against food-borne pathogens. First, the Viscum album var. coloratum was extracted with methanol at room temperature and the fractionation of the methanol extracts was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol, respectively. The antimicrobial activity of the Viscum album var. coloratum extracts was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The petroleum ether extracts of Viscum album var. coloratum showed the highest antimicrobial activity against Bacillus cereus and Shigella dysenteriae. Synergistic effect in inhibition was observed when Viscum album var. coloratum extract was mixed with Perillae folium extract as compared with each extract alone. Finally, the growth inhibition curves were determined by using petroleum ether extracts of Viscum album var. coloratum against Bacillus cereus and Shigella dysenteriae. The petroleum ether extract of Viscum album var. coloratum had strong antimicrobial activity against Bacillus cereus at the concentration of 5,000 ppm. At this concentration, the growth of Bacillus cereus was retarded more than 24 hours and up to 12 hours for Shigella dysenteriae. In conclusion, the petroleum ether extracts of Viscum album var. coloratum inhibit efficiently Bacillus cereus and Shigella dysenteriae.

• BMB Reports
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• v.52 no.8
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• pp.490-495
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• 2019

Using tunneling nanotubes (TNTs), various pathological molecules and viruses disseminate to adjacent cells intercellularly. Here, we show that the intracellular invasion of Mycoplasma hyorhinis induces the formation of actin- and tubulin-based TNTs in various mammalian cell lines. M. hyorhinis was found in TNTs generated by M. hyorhinis infection in NIH3T3 cells. Because mycoplasma-free recipient cells received mycoplasmas from M. hyorhinis-infected donor cells in a mixed co-culture system and not a spatially separated co-culture system, direct cell-to-cell contact via TNTs was necessary for the intracellular dissemination of M. hyorhinis. The activity of Rac1, which is a small GTP binding protein, was increased by the intracellular invasion of M. hyorhinis, and its pharmacological and genetic inhibition prevented M. hyorhinis infection-induced TNT generation in NIH3T3 cells. The pharmacological and genetic inhibition of Rac1 also reduced the cell-to-cell dissemination of M. hyorhinis. Based on these data, we conclude that intracellular invasion of M. hyorhinis induces the formation of TNTs, which are used for the cell-to-cell dissemination of M. hyorhinis.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.205-214
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• 2021

The use of the supernatant from a Bacillus subtilis culture mixed with sodium bicarbonate was explored as a means of controlling stem brown spot disease in dragon fruit plants. In in vitro experiments, the B. subtilis supernatant used with sodium bicarbonate showed a strong inhibition effect on the growth of the fungus, Neoscytalidium dimidiatum, the agent causing stem brown spot disease and was notably effective in preventing fungal invasion of dragon fruit plant. This combination not only directly suppressed the growth of N. dimidiatum, but also indirectly affected the development of the disease by eliciting the dragon-fruit plant's defense response. Substantial levels of the pathogenesis-related proteins, chitinase and glucanase, and the phenylpropanoid biosynthetic pathway enzymes, peroxidase and phenyl alanine ammonia-lyase, were triggered. Significant lignin deposition was also detected in treated cladodes of injured dragon fruit plants in in vivo experiments. In summary, B. subtilis supernatant combined with sodium bicarbonate protected dragon fruit plant loss through stem brown spot disease during plant development in the field through pathogenic fungal inhibition and the induction of defense response mechanisms.

• Applied Biological Chemistry
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• v.26 no.1
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• pp.35-40
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• 1983

The inhibitory activity of 20 Lactic strains from Kimchi was tested against Escherichia coli and other microorganisms. Of the lactic strains investigated, A7 (Pediococcus cerevisiae) and C4(Leuconostoc spp.) were the most effective in restricting the growth of test organisms. The mixed culture inoculation of each selected lactic strain and Escherichia coli resulted in a drastic reduction in the plate count of Escherichia coli after 24 hours. Similar results were obtained when Staphylococcus aureus and Bacillus cereus were used as test organisms. For all test organisms, the presence of A7 caused a higher death rate constant than that of C4. Addition of catalase in the mixed culture did not prevent inhibition, suggesting that hydrogen peroxide did not cause the inhibition. The filtrate of A7 culture added to Escherichia coli showed identical inhibitory action, however heat treatment of filtrate at $80^{\circ}C$ 30min. destroyed the inhibitory activity. A7 filtrate treated with trypsin substantially lost the inhibitory effect, but not by pepsin. The results imply that the protein-like compound(s) is the principal inhibitor produced by this lactic strain.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.4
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• pp.398-407
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• 2020

The inhibitory effect on α-glucosidase, a marker of postprandial hyperglycemia, and angiotensinconverting enzyme (ACE), a marker of hypertension, was analyzed using non-fermented green tea and three different types of fermented tea, which are popular beverages in modern life. Green tea was mixed with trace amounts of vanadate (50 ㎍/mL), which has insulin-mimetic effects, to investigate the synergistic effect of vanadate on the inhibition of α-glucosidase. The concentration of epigallocatechin gallate (EGCG) and caffeine was also checked. The extracts of green tea and fermented teas showed clear inhibition on α-glucosidase, which caused a decrease in the postprandial glucose levels. The inhibitory effect was most prominent in the 20% fermented tea. Trace amounts of vanadate (50 ㎍/mL)-mixed green tea extract had twice the inhibitory effect on α-glucosidase than the pure tea extract. All teas showed inhibitory effects on ACE. Among those, the effect was most prominent in green tea, which had higher concentrations of EGCG. In contrast, the postprandial glucose-lowering effect and ACE inhibition of the fermented teas, which have a lower level of EGCG, was attributed to some other different functional substances.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.313-317
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• 1998

This study was perfonned to investigate the possible effect of Bacillus subtilis which is the predominant species of bacteria in Korean soy sauce, soy paste, and Meju (soybean cake) on the growth and aflatoxin production of Aspergillus parasiticus ATCC 15517. The microorganisms were grown in a modified APT broth and incubated at $30^{\circ}C$ for 12 days. Aflatoxins were determined using high performance liquid chromatography (HPLC). A remarkable inhibition of the growth of Aspergillus parasiticus was observed during the incubation period when in the presence of B. subtilis (mixed culture). Dry mycelial weight in the mixed culture was significantly reduced by 85.3% in comparison to the control at the end of the incubation period (p<0.01). Lower levels of aflatoxins were found in the mixed culture than in the monoculture. At the end of the incubation period aflatoxin production was significantly inhibited by more than 50% (p<0.05). These results indicate that B. subtilis mainly inhibites the growth and aflatoxin production of toxigenic Aspergillus in Meju, soy sauce and soy paste. Although its effect on aflatoxin production was less pronounced, we could expect more inhibition by another bacteria related with fermentation in Meju.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.509-515
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• 1996

The effects of sour liquid ferments with lactic acid bacteria on the baking properties and qualities of White Pan Bread were studied. The mixed culture of Lactobacillus brevis and Lactobacillus plantarum had higher acid equivalents and lower pH-values than single or mixed culture of other lactic acid bacteria which had been used for traditional sour dough bread. Optimum conditions of the incubation of lactic acid bacteria, which are incubation temperature time and culture medium compositions for lactic fermentation, were also investigated to find out optimum activity for good bread making. The mixed culture of L. brevis and l. plantarum incubated for 24 hours at 3$0^{\circ}C$ had the most optimum activity for bread manufacturing process and the qualities of the products. The addition of sour liquid ferments to the sponge dough effected on fermentation activity of the sponge dough to lower the level of pH to 4.64 and to produce more total titratable acidity(TTA) of 0.545, whereas conventional sponge dough bread had 0.46% of TTA. On comparison with control bread, the bread made with sour liquid ferments was found to have better specific volume, taste, symmetry, especially, organoleptic characteristics due to lactic acid, acetic acid and amino acid produced by lactic acid bacteria. Sour dough bread with liquid ferment was considered to be more effective to the inhibition of staling during storage for 6 days at $25^{\circ}C$ and to have longer shelf-than control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.143-148
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• 2007

This study was to investigate the mixed buckwheat flour quality by observing antimutagenic and cytotoxic effects of mixed buckwheat flour extracts using Ames test and SRB (sulforhodamine B) assay. Samples were prepared to the ratio of 100% (B1), 90% (BF1), 80% (BF2), 70% (BF3) and 60% (BF4) (w/w) flour buckwheat based on wheat flour weight. The initial pasting temperature in an amylograph was increased according to the increase of the buckwheat flour. The water absorption in farinograph decreased with the addition of buckwheat flour. The inhibition rates of B1, BF3 and BF4 extract (160 g/plate) were 45%, 37.3% and 42% against the mutagenesis of Salmonella Typhimurium TA100 induced by MNNG $(0.4{\mu}g/plate)$, respectively. In addition, the B1 at the same concentration showed 64% and 44.3% inhibition on the mutagenesis of Salmonella Typhimurium TA98 and TA100 induced by 4NQO $(0.15{\mu}g/plate)$, respectively. In SRB assay, human breast adenocarcinoma (MCF 7), human hepatocellular carcinoma (Hep3B), human stomach adonocarcinoma (AGS), human lung carcinoma (A549) and human cervical adenocarcinoma (HeLa) proliferations were inhibited by the increase in the sample concentration.

• Korean Journal of Ecology and Environment
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• v.37 no.1 s.106
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• pp.64-69
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• 2004

Growth inhibition of Microcystis aeruginosa was examined with single-or mixed treatment of algicidal bacterium Streptomyces neyagawensis and heterotrich ciliate Stentor roeseli, which isolated from natural freshwater. The harmful Cyanobac-terium, Microcystis aeruginosa density was effectively suppressed by the algicidal bacterium Streptomyces neyagawensis, and the bacterial biomass was few changed. The heterotrich ciliate S, roegeji isolated from the eutrophic Pal'tang riverine, Korea suppressed the algal biomass effectively. But mixed-treatment of both bio-agents was less effective, leading to an increase in algal density.