• Research in Plant Disease
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• v.10 no.4
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• pp.285-289
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• 2004

The bloody watermelon exhibiting dark red and fermentation off-flavor results in a great economic loss. As an effort to clarify the cause of the bloody watermelon, relationship between the fermentational off-flavor and the presence of endophytic bacteria was studied. The number of endophytes was 2.2-37.0 ${\times}10^3$ cfu/g fw (fresh weight) in normal watermelons, compared to 1.26-1.75 ${\times}10^6$ cfu/g fw in bloody ones. Seventeen bacteria among 56 isolates from bloody watermelons could induce bloody watermelons. The bacteria responsible for bloody watermelons were mainly Gram negative: aerobic Pseudomonas spp and some anaerobic bacteria. The results in this study strongly suggested that the bloody watermelons were produced by abnormal fermentation and growth of endophytic Gram negative bacteria.

• Advances in Traditional Medicine
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• v.8 no.4
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• pp.339-348
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• 2008

Butea frondosa has been used traditionally as a topical formulation in the treatment of many diseases and disorders. Two compounds [BF-1 (crystalline flavonol quercetin) and BF-2 (tannin) from ethyl acetate fraction of ethanolic extract] were isolated from the bark of Butea frondosa. The stereostructures of the compounds were determined on the basis of chemical and physicochemical evidence. BF-1 and BF-2 were screened in vitro for possible antibacterial property against 112 bacteria comprising 3 genera of Gram-positive and 12 genera of Gram-negative types. It was found that both BF-1 and BF-2 exhibited inhibitory activity against several bacteria. Most of these strains were inhibited by BF-1 at $50-200\;{\mu}g/ml$, while BF-2 ($MIC_{50}$ $400\;{\mu}g/ml$) was much less active. The bacteria could be arranged in the decreasing order of sensitivity towards BF-1 in the following manner: S. aureus, Bacillus spp., Salmonella spp., Vibrio spp., Shigella spp., E. coli and Pseudomonas spp. The $MIC_{50}$ of the compound was $50\;{\mu}g/ml$ while the $MIC_{90}$ was $100\;{\mu}g/ml$. The decreasing order of sensitivity towards BF-2 was V. cholerae, Bacillus spp., S. aureus, V. parahaemolyticus, Salmonella spp. and Proteus spp. BF-1 was bactericidal in action. In vivo studies with this extract showed that it could offer statistically significant protection (p < 0.01) to mice challenged with a virulent bacterium. The inhibitory activity of Butea frondosa against Gram-positive and Gram-negative bacteria indicates its usefulness in the treatment of common bacterial infections. The potentiality of BF-1 as an antibacterial agent may be confirmed further by pharmacological studies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.621-625
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• 2004

Electron donating abilities, nitrite scavenging effects and antimicrobial activities of various fractions obtained from ethanol extract of Smilax china were examined. Among the fractions investigated, the highest electron donating ability was determined with ethyl acetate fraction showing about 81.0% when reacted for 10 min. However, the lowest ability was found from chloroform fraction. Ethyl acetate and butanol fractions also showed very high nitrite scavenging activity at all concentrations tested. All the fractions revealed antimicrobial activity against Listeria monocytogenes and Staphylococcus aureus, Gram (+) bacteria, at both 2.5% and 5.0% concentrations. However, no antimicrobial activity was observed on Escherichia coli O157:H7 and Salmonella Typhimurium, Gram (-) bacteria, at 2.5%, but very low activity was detected by 5.0% concentration of ethanol extract, ethyl acetate and water fractions.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.5
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• pp.57-64
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• 2010

A performance test of inter propellant seal for a 75 ton class turbopump is conducted using water to evaluate leakage and endurance performance. Each part of fuel pump side and oxidizer pump side for a prototype inter propellant seal has been tested for verifying endurance performance during total accumulated test time 2,100 sec in water. The fuel pump side part with one-stage seal of carbon floating ring shows average leakage rate 13.7 gram/sec under average seal differential pressure 9.4 bar. On the other hand, the oxidizer pump side part with two-stage seal assembly of carbon floating rings shows average leakage rate 7.3 gram/sec under average seal differential pressure 9.5 bar. After the endurance performance test, the inter propellant seal shows good physical condition. A leakage performance test of the inter propellant seal for cryogenic environment will be performed using LN2 in the near future.

• Food Science and Preservation
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• v.8 no.1
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• pp.86-91
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• 2001

To study the availability of the Korean Atractylodes japonica Koidz. as ingredients for functional flood, functional properties of solvent extracts were investigated and the results were followed. Yield was 14.8% by ethanol extraction of fresh Korean A. Japonica and 17.7% by water fraction. Acetone extract and butanol fraction showed stronger activity of the hydrogen donating activities, each of 72.9% and 74.2%, respectively, in fresh Korean A. japonica and methanol extract and butanol fraction showed stronger activity of the nitrite scavenging effects, each of 95.0% and 79.2%. in fresh Korean A. japonica. Among the solvent extacts from fresh Korean a. japonica, extract by methanol showed strong antimicrobial activity in which clear zone showed 20 mm for Bacillus subtilis and 19 mm for Pseudomonas aeruginosa. Butanol fraction derived from methanol extract showed moderate antimicrobial activity : 18 mm clear zone for Bacillus subtilis and Vibrio parahaemolyticus. Minimum inhibitory concentrations of methanol extract and butanol fraction were about 2 mg/disc and 4 mg/disc against gram(+) bacteria and 6 mg/disc against gram(-) bacteria, respectively.

• The Korean Journal of Mycology
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• v.13 no.2
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• pp.89-97
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• 1985

To find antibacterial strains of the soil microorganisms in Korea, they were isolated from the soil samples of different locations and screened for antibacterial activity against several standard microorganisms. An isolate among them had antibacterial activities against gram-positive and gram-negative bacteria. The examination of its morphological, biochemical, cultural and physiological characteristics according to the International Streptomyces Project methods showed that it belongs to the genus Streptomyces. This strain appears to be a novel strain when it was compared with those species of the genus which have been so far reported. The antibiotic metabolite was produced in the submerged culture of the strain. This metabolite was extracted from the culture filtrate and purified by ion-exchange column chromatography. Physico-chemical properties of the antibacterial metabolite were characterized.

• Food Science and Preservation
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• v.20 no.3
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• pp.419-423
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• 2013

The objective of this study was to characterize the bactericidal effect of 461nm visible-light LED on three common foodborne bacteria: Escherichia coli O157:H7, Staphylococcus aureus and Vibrio parahaemolyticus. Tests were conducted against pathogen strains that were treated with 461nm LED for 10 h at $15^{\circ}C$. The E. coli (ATCC 43894, ATCC 8739 and ATCC 35150) and the S. aureus (ATCC 27664, ATCC 19095 and ATCC 43300) had average reductions of 2.5, 6.6, 1.5, 2.5 and 2.0 log CFU/mL, respectively, after they were exposed for 10 h to 461nm LED light (p<0.05). In contrast, V. parahaemolyticus (ATCC 43969) had 6 log CFU/mL reductions after it was exposed for 4 h to 461nm LED light. The results showed that both the Gram-positive and Gram-negative bacteria were inactivated with 461nm LED light exposure. Also, the Gram-negative bacteria were more sensitive to the LED treatment than the Gram-positive bacteria. These results show the potential use of 461nm LED as a food preservation and application technology.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.506-514
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• 2010

A new series of ligands N-[(benzoylamino)-thioxomethyl]-amino acid (HL) were synthesized by reaction of benzoylisothiocyanate with various amino acids namely aspartic acid [BATA] (1), glutamic acid [BATG] (2), methionine [BATM] (3), leucine [BATL] (4), and tryptophan [BATT] (5). The ligands were characterized by elemental analysis, IR and NMR spectra. Some transition metal complexes ($ML_2$) for these ligands (6-8) were prepared; [M=Cu(II), Co(II), or Ni(II)], and characterized by elemental analysis, IR and $^1H$ NMR spectra. Antibacterial study showed that all the ligands have no antibacterial activity, whereas ($ML_2$) complexes; [M = Cu(II), Co(II), or Ni(II)] have antibacterial activity towards (Gram -ive) Escherichia (NCTC5933) and (Gram +ive) Staphylococcus (NCTC6571) and have no toxicity on (BALB/C) Albino mice.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.47-53
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• 2010

A performance test of a 75 ton class turbopump inter propellant seal is conducted using water to evaluate leakage and endurance performance. Each fuel pump side part and oxidizer pump side part of a prototype inter propellant seal has been tested for verifying endurance performance during total accumulated test time 2,100 sec in water. The fuel pump side part with 1 stage carbon floating ring seal shows average leakage rate 13.7 gram/sec under average seal differential pressure 9.4 bar. On the other hand, the LOx pump side part with 2 stage carbon floating ring seal shows average leakage rate 7.3 gram/sec under average seal differential pressure 9.5 bar. After the endurance performance test, the inter propellant seal shows good physical condition. A cryogenic leakage performance test of the inter propellant seal will be performed using LN2 in the near future.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.166-185
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• 2002

Aroma oils extracted from the natural material have antibacterial, antivirus, antiinflammatory, and preservative effect. The preserve efficacy testing between aroma oils and parabens as an artificial preservative had been performed and then it had been suggested that aroma oil was possibile to apply to the cosmetics. Aroma oils were pine, rosemary, lemon and eucalyptus, and parabens were methylparaben, blitylparaben. Antiseptic concentrations of aroma oils and parabens having 0.0, 0.1, 0.2, 0.4, 0.8, 1.0wt% were tested respectively. Escherichia coil(ATCC No.8739), Pseudomonas aeruginosa(ATCC No. 9027) which are gram-negative and Staphylococcus aureus (ATCC No. 6538), Bacillus subtilis(ATCC No. 6633) which are gram-positive were used as the test organisms. Disk paper and broth dilution methods were used as the methods of preservative efficacy testing. The antibacterial activity of aroma oils and parabens for gram-positive were better than that for gram-negative. For the antibacterial activity aroma oils were better than parabens. Among the aroma oils, rosemary and pine having superior antibacterial activity were selected and blended to illuminate if there is any synergy, There was synergical effect and optimum ratio of aroma blend is 3 : 1(rosemary pine) in this study.