• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.752-755
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• 2003

The antimicrobial activity of fresh garlic juice against Escherichia coli O157:H7 was investigated. When E. coli O157:H7 was cultured for 18 hr in the trypticase soy broth containing 1%, 3%, and 5% garlic juice, viable cell number of E. coli O157:H7 was reduced to $2.3{\times}10^2\;CFU/mL$ at 5% from $7{\times}10^8\;CFU/mL$ at the non-treated culture, respectively. The inhibitory effects of the ground beef treated with 3%, 6%, and 10% garlic juice against E. coli O157:H7 was significantly enhanced with approximate 2 log-reduction compared to that of ground beef without garlic. There was no significant difference in the inhibition of E. coli O157:H7 among the groups with different amounts of garlic juice (p<0.05). These results suggest that garlic juice may function well as a natural preservative in food system.

• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.341-348
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• 2010

Antifungal and antibacterial activities of wood vinegars were investigated in this study in order to apply for the natural fungicides and food preservatives. The antifungal activities of wood vinegars were measured as a hyphal growth inhibition rate using four plant pathogenic, four wood rot and one mushroom pathogenic fungi. Inhibition effect on the fungi growth was explicitly observed at the concentrations higher than 0.5% of unrefined wood vinegar and higher than 1.0% of refined wood vinegar, respectively, suggesting that unrefined wood vinegars showed the higher antifungal activities than that of refined wood vinegars. The highest inhibition effect on the fungi growth was shown in Libertella betulina which is a mushroom pathogenic fungus. In addition, the wood vinegars from Pinus densiflora showed the higher antifungal activities against the plant pathogenic and wood rot fungi than that from Quercus spp.. On the other hand, the antibacterial activities of wood vinegars were determined by a paper disc method using the three gram positive and five gram negative bacteria. The unrefined wood vinegars showed a prominent effect on the suppression of bacteria growth at the concentration of 10%, while the suppression of bacteria growth was not observed in the refined wood vinegars. These results also suggest that the unrefined wood vinegars showed the higher antibacterial activities than the refined wood vinegars. The antibacterial activities of wood vinegars against gram positive bacteria were higher than those of wood vinegars against gram negative bacteria. From these results, it can be inferred that the wood vinegars has the strong antimicrobial activities and can be applied as the natural fungicides and food preservatives.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.746-749
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• 2002

From 7 different medicinal herbs, Rubus coreanus miquel, Therminalia chebula Retz and Rhus javanica was selected by paper disk method against 10 different microorganisms. The ethanol extracts of selected herbs was added into Tofu, and the total viable cell counts was determined. After 4 days, total viable cell count reached to $10^7$ and the Tofu putrefacted. The tested sample added with 0.01% of Terminalia Chebula Retz extract, the shelf-life was extended as 108.8%, with 0.05% was 117.3% and with 0.1% was 132.6%. Among 3 kinds of medicinal herb, Therminalia chebula Retz has better powerful activity than others.

• Food Science and Preservation
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• v.19 no.6
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• pp.919-924
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• 2012

This study was conducted to investigate the antimicrobial activities and antioxidant activities of the Korean mistletoe extract and its solvent fractions (e.g. n-hexane, ethyl ether, ethyl acetate, butanol). Ethyl ether fraction against Bacillus cereus showed stronger activities than benzoic acid (2.5 mg/mL). The MIC of korean mistletoe extract and slovent fractions were in the range of 6.25-25 mg/mL. The MIC (6.25 mg/mL) of ethyl acetate fraction onto Staphylocossus aureus was the lowest among them. Ethyl ether fraction which showed the strongest antioxidant activities by DPPH (1,1-diphenyl-2-picryl-hydrazyl) and FRAP (ferric ion reducing antioxidant power) methods had the highest total phenolic contents. It is suggested that Korean mistletoe could be utilized as natural preservative material through the study of the active compounds from ethyl ether fraction.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.5
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• pp.435-444
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• 2016

This study was conducted to investigate the effects of natural preservatives (G3, G3-1, F3, and F3-1) using Cordyceps militaris on improvement of food quality and safety of noodle during storage. Wheat flour noodle were prepared using three different concentrations of natural preservatives (0.100, 0.200, and 0.400%). Changes in microbial populations, pH value, titratable acidity, and sensory evaluation were measured during storage at $12{\pm}2^{\circ}C$ for 3 days. Overall, use of natural preservatives resulted in lower levels of total mesophilic bacteria, coliform, yeast and mold in noodle compared to the control. In particular, natural preservatives using $2{\times}$ MIC concentrations (0.400%) of F3 and F3-1 were effective at maintaining levels of total mesophilic bacteria for noodle during storage. The pH values of noodle made with F3 and F3-1 were higher than the others. The titratable acidity of noodle with natural preservatives did not significantly change during storage. In sensory evaluation, appearance, color, and overall acceptability of noodle with F3 and F3-1 were preferred than the control. These results could provide useful information for developing an alternative preservation method to improve food quality and shelf-life of noodle using natural preservatives.

• Food Science and Preservation
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• v.14 no.5
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• pp.516-525
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• 2007

The effect on quality improvement of Chokochujang by the addition of green tea extract (GT) was evaluated on the basis of total cell numbers, pH, acidity, sugar content and sensory evaluation during its storage at $25^{\circ}C$ and $37^{\circ}C$ for 3 weeks. A dorminant strain was isolated from the Chokochujang and identified as Bacillus amyloliquefaciens ER282 based on the 16S rDNA sequence. The ethanol extract from GT was investigated for its antibacterial activity aid showed good activities enough to use for Chokochujang as a natural preservative. Growth of microorganisms was significantly inhibited by adding GT extract to Chokochujang but pH, acidity, sugar content and color was not much changed. Sensory evaluation and overall preference, however, was continuously declined as storage period increased, whereas the addtion of 3% GT extract could delay the quality loss of Chokochujang during storage at $25^{\circ}C$ and $37^{\circ}C$ for 3 weeks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.814-821
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• 2000

In order to investigate the possible use of omija extract as natural preservatives for nabak kimchi omija extract was tested for antioxidation and electron-donating ability and further more antimicrobial activites against lactic acid bacteria of nabak kimchi. The concentration of the test sample used were 0.5, 1.0, 1.5, 2.0%. Antioxidative activity measured the TBA value, when omija extract concentration % is higher the antioxidation effect were more evident with the increased omija extract concentrations, and showed a high electron donating activity more than 1.0%. As the result of isolated lactic acid bacteria from nabak kimchi the primary separation tool 117 strains, of these 4 strains which had excellent growth and a strong acid formation capability was selected the second time and Lactobacillus brevis, Lactococcus faecalis, Leuconostoc mesenteriodes, Lactobacillus palantarum were identified. After measuring the antimicrobial activity of the four lactid acid bacteris, except Lactobacillus brevis the other three bacteria showed strong antimicrobial activities. The results suggest the possible use of the omija extract as natural preservative for nabak kimchi.

• Food Science and Preservation
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• v.11 no.1
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• pp.17-21
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• 2004

The antimicrobial effect of mixed solution of botanical antimicrobial agent-citrus product (BAAC) and such a natural additive as aloe, ginseng or Prunus mume extract on the spoilage microorganisms of soybean sprouts were investigated by paper disk method. The mixture (BAAG) of BAAC and ginseng extract showed the remarkable antimicrobial activity in the result of the experiment. Therefore, we used BAAG as pre-soaking and cultivating solution of soybean sprouts. Total bacterial and Escherichia coli cell count of soybean sprouts pre-soaked and cultivated in the BAAG-diluted solution (50 ppm) showed 2.5 ${\times}$ 10 CFU/mL and 1.3 ${\times}$ 10 cfu/mL in comparison with 3.5 ${\times}$ 10$^3$ cfu/mL and 5.8 ${\times}$ 10$^3$ cfu/mL of the control, respectively. BAAG-treated soybean sprouts also showed no slimy brown product and undesirable odor characterized in the control. It was confirmed that BAAG could be a proper pre-soaking and cultivating solution of soybean sprouts.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1109-1114
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• 1999

The antifungal activity of ethylenediaminetetraacetic acid (EDTA), an antioxidative food preservative, was investigated against Saccharomyces cerevisiae. At the general condition for antifugal test, EDTA exhibited the minimum inhibitory concentration (MIC) of 200 ${\mu}g/ml$ and the minimum fungicidal concentration (MFC) of 6,400 ${\mu}g/mL$, As seen with the antibacterial activity, the antifungal activity of EDTA was greatly decreased by high inoculum size, acidic medium, and cation ($Ca^{++},\;or\;Mg^{++}$) added to medium. On the other hand, when EDTA was combined with polygodial isolated from natural food spice, they showed strong synergism on the antifungal activity. Further, the diminishing antifungal activity of EDTA by high inoculum size, acidic medium, and cation ($Ca^{++}\;or\;Mg^{++}$) added to medium was considerably improved by the combination with polygodial.

• Korean journal of food and cookery science
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• v.31 no.5
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• pp.515-523
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• 2015

In the study reported here, the antimicrobial and antioxidant activities of the ethanol leaf extract of Dendropanax morbiferus Lev. from Jeju Island was investigated. Of the 14 strains of 12 species of microorganisms tested, the extract exhibited antimicrobial activity observed against seven Gram-positive bacteria of four species, but not against six Gram-negative bacteria and a yeast strain. Using the disc diffusion method, the diameter of the inhibition zone increased with application of the extract with every strain and the highest growth inhibition was exhibited with Staphylococcus aureus KCTC 1916 at 5 mg/ml. The minimal inhibitory concentration of the extract (MIC) by turbidity was 2.5 mg/ml against Bacillus cereus KACC 12672 and 15 mg/ml when with Enterococcus faecalis KCTC 3206. The minimum bacterial concentration (MBC) values defined as being $${\geq_-}99.9%$$ reduction in viable cells against the tested strains was higher than the MIC values. Time killing curves using the optimum MIC were performed on seven strains incubated for 48 hr. The growth of B. cereus KACC 12672 was detected after 12 hr and no significant growth was found in the others strains after 48 hr (p<0.05). The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity of the ethanol leaf extract was similar to that of butylated hydroxyanisole (BHA) at the same concentration. These results indicate that leaf extract of D. morbiferus Lev. can be utilized as a natural preservative and an antioxidant.