• Journal of Microbiology and Biotechnology
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• v.27 no.4
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• pp.759-767
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• 2017

Lactophoricin (LPcin), which is a part of proteose peptone isolated from bovine milk, is a cationic amphipathic ${\alpha}-helical$ antimicrobial peptide. Its truncated variants and mutated analogs were designed and their antimicrobial activities were evaluated by using various assays, like broth dilution methods and disk diffusion methods as well as hemolysis assay. Three analogs, LPcin-C8 (LPcin-YK1), LPcin-T2&6W (LPcin-YK2), and LPcin-T2&6W-C8 (LPcin-YK3), which showed better antibiotic activities than LPcin, were selected. Their secondary structures were also characterized by using CD spectropolarimetry. These three analogs of LPcin could be used as an alternative source of powerful antibacterial agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1022-1028
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• 1999

The solvent extracts of Ulmi cortex, which were extracted by using several solvents with different polarities, were prepared for utility as a natural preservatives. The antimicrobial activities and cell growth inhibitions were investigated to each strain with the different concentrations of Ulmi cortex extracts. Methanol extract showed the highest antimicrobial activity. The methanol extract was represented the broad antimicrobial activities for the gram positive and negative strains. Minimum inhibitory concentrations (MIC) for each strains were appeared to around 0.3mg/ml at each of Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus. The cell growth inhibitions were not shown on Lactobacillus bulgaricus, Lac tobacillus plantarum, and Bifidobacterium bifidum, but greatly on the Clostridium butyricum. The meth anol extracts were further reextracted sequentially with hexane, chloroform, ethyl acetate, and butanol for purifying crude methanol extracts. The extract, which was reextracted by butanol, showed the highest antimicrobial activity.

• Natural Product Sciences
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• v.5 no.4
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• pp.172-176
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• 1999

A total of 43 extracts from 21 species of Malaysian flowering plants were screened for antimicrobial and cytotoxic activities. Antimicrobial activity was tested against fungi, including yeast and candida, as well as Gram-positive and Gram-negative bacteria, and cytotoxicity was assayed using the CEM-SS and HT-29 cell lines. The methanol extracts of the roots and stems of Plumeria acutifolia showed the highest antimicrobial activity, i.e. against Saccharomyces cerevisiae and Candida lipolytica, and mostly moderate activity against the other microbes such as Aspergillus ochraceous and Saccharomyces lipolytica. Phyllanthus emblica also showed moderate activity especially that of the methanol extracts. The methanol extract of the roots of Plumeria acutifolia showed the strongest cytotoxic activity $(CD_{50}=\;3\;{\mu}g/ml)$. Most of Zingiberaceae species gave negative results for antimicrobial activity and showed low cytotoxic activity.

• Plant Resources
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• v.8 no.2
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• pp.96-102
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• 2005

As part of developing natural food preservatives, the antimicrobial effect of ethanol and water extracts from the Cruciferous vegetable was examined Korean traditional Brassica juncea Coss. was used widely as an ingredient of Kimchi, a natural flavoring and spice for a long time. Antimicrobial activities were examined against 15 microorganisms which were food-born pathogens and/or food poisioning microorganisms and food-related bacteria and yeasts. Ethanol extract from leaf mustard showed an antimicrobial effect in most of the strains used in the present study. The lowest minimum inhibitory concentration (MIC) were seen in Bacillus subtilis and Bacillus natto at 10 mg/ml. MIC of water extract was 40-60 mg/ml for bacteria and yeast. Antimicrobial activity of the ethanol extract was not disappeared by the heating at $121^{\circ}C$ for 15 min and not affected by pH.

• Journal of Pharmaceutical Investigation
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• v.17 no.1
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• pp.31-37
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• 1987

The studies on concurrent administrations of herb preparations(Daesiho-tang, Daehwangmogdanpi-tang, Dohaegseunggi-tang, Baenongsangeub-tang and Jeoryeong-tang) with indomethacin and tetracycline were carried out to investigate the antiinflammatory, antimicrobial, liver-protective and antiulcer activities. The results showed that the concurrent administrations of herb preparations with indomethacin and tetracycline increased significantly the antiinflammatory activities and antimicrobial activities respectively, and also improved the liver-protective activities and antiulcer activities against indomethacin or tetracycline-induced liver defect and Shay ulcers in rats, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1106-1112
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• 2007

The solvent extracts of Euphorbia helioscopia, which were extracted by using several solvents with different polarities, were prepared for utility as natural preservatives. The E. helioscopia extract by 80% ethanol was sequentially fractionated with n-hexane, dichloromethane, ethylacetate, and butanol. In order to effectively screen for a natural preservatives agent, we first investigated the antioxidant activities such as DPPH radical scavenging capacity, superoxide radical scavenging capacity, and xanthine oxidase inhibitory activity of the E. helioscopia extracts. By the screening system, we found that ethylacetate fraction had the strongest antioxidant activity in a dose-dependent manner. The antimicrobial activities and cell growth inhibition were investigated for each strain with the different concentrations of E. helioscopia extracts. Antimicrobial activities were shown in ethylacetate fraction of E. helioscopia; however, ethanol, butanol and water fractions showed weak antimicrobial activity against the tested microorganisms. Among the five fractions, ethylacetate fraction showed the highest antimicrobial activities against microorganisms tested, such as Bacillus sublitis, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella Enteritidis and Salmonella Typhimurium. The polyphenol content from ethanol, n-hexane, dichloromethane, ethylacetate, butanol, and water fractions were 207.46 mg/g, 45.45 mg/g, 138.23 mg/g, 678.02 mg/g, 278.91 mg/g, and 63.76 mg/g, respectively. There seems to be a close relationship between antioxidant activities, and antimicrobial activities and polyphenol content in natural plant. From these results, it is suggested that E. helioscopia could be used for the ethylacetate fraction and could be suitable for the development of a food preservative.

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.109-116
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• 2000

This study was carried out to screen herbs among herbal plants showing antimicrobial activity against some food spoilage and pathogenic microorganisms. One hundred fifteen kinds of herbal plants were extracted by 70% ethanol, and then they have been screened for antimicroorganisms. Six herbal plants such as Salviae radix, Dryopteris rhizoma, Terminaliae fructus, Araliae radix, Psoraleae fructus and Schisandrae fructus showed strong antimicrobial activities against Bacillus subtilis. Antimicrobial activities were showed in Anemarrhena radix and Dryopteris rhizoma on Candida albicans, and in Anemarrhenae radix, Dryopteris rhizoma and Polygalae radix on Schizosaccharomyces sp. It was revealed that eight herbal plants such as Dryopteris rhizoma, Salviae radix, Sappan ligunum, Sinomeniae radix, Schisandrae fructus, Rhui fructus, Sophorae radix and Inulae radix also showed antimicrobial activities on Streptococcus mutans. In addition, Anemarrhena radix, Curcuma tuber, Inulae radix, Polygonum radix, Sanguisorbae radix, Scutellariae radix and Terminaliae fructus and showed antimicrobial activities on Trichophyton mentagrophytes. Four kinds of herbal plants such as Dropteris rhizoma, Salviae radix, Terminaliae fructus and Scutellariae radix which showed broad antimicrobial spectrums were mixed by 1 : 1 ratio with the other herbal paints showing relatively strong microbial activities such as Terminaliae fructus, Sinomeniae radix and Scutellariae radix etc. The extracts of mixed herbal paints showed higher antimicrobial activities than those of single herbal plant.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.293-296
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• 1995

Fig leaves were extracted with methanol and then fractionated with ethyl acetate and various buffers to get active fractions and determined the antimicrobial activities. The acidic and phenolic fractions fractionated from the methanol extract of fig leaves showed the strong antimicrobial activities, but the basic and neutral fractions did not show any activities. The degree of antimicrobial activities of phenolic fraction against tested bacteria was higher than those of acidic fraction, but these against yeasts and mold were almost equivalent to those of acidic fraction. Especially, phenolic fraction was mostly affected on Staphylococcus aureus and Pseudomonas aeruginosa. Four antimicrobial substances purified from the phenolic fraction which showed the strongest antimicrobial activities among the fractions from fig leaves, were identified as psoralen($C_{11}H_{6}O_{3}$, MW. 186), bergapten($C_{12}H_{8}O_{4}$, MW. 216), ${\beta}$-sitosterol($C_{29}H_{50}O$, MW. 414) and umbelliferone ($C_{9}H_{6}O_{3}$, MW. 162).

• The Korea Journal of Herbology
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• v.28 no.3
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• pp.45-51
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• 2013

Objectives : This study was conducted to measure the antioxidative and antimicrobial activities of water- and ethanol-extracts from Betula platyphylla var. japonica, Punica granatum and Rhus javanica against various species of anaerobic bacteria. Methods : In order to evaluate the antioxidative and antimicrobial activities of water- and ethanol-extracts, DPPH radical scavenging and superoxide dismutase (SOD)-like activities were measured in various species such as Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Propionibacterium acnes that induce skin inflammation. Also the total amount of phenol in each water- and ethanol-extract was measured to identify its role in the antioxidative and antimicrobial activities of water- and ethanol-extracts from Betula platyphylla var. japonica, Punica granatum and Rhus javanica. The antibacterial activity of the extracts was measured by confirming the lowest concentrations in disk diffusion and minimum inhibitory concentration (MIC) tests. Results : It was observed that RJE (Rhus javanica-EtOH extracts) show the highest content of total phenol. In addition, for RJE the total phenol content was higher from samples taken from domestic sources than from samples taken from foreign sources. DPPH radical scavenging activity was increased by treatment with PGE (Punica granatum-EtOH extracts), RJE and RJW (Rhus javanica-water extracts). It was observed that SOD-like activity was highest in the treatment with PGE. All of the extracts showed antimicrobial activity on S. epidermidis, S. aureus, P. acnes and E. coli, including those from Punica granatum, and it was noted that the activity was higher with RJE than with RJW. Conclusions : These results provide evidence that ethanol extracts of Punica granatum and Rhus javanica may have a beneficial role as antioxidants and antibiotics. Extracts from domestic samples of Betula platyphylla var japonica appeared to have a greater efficacy than extracts from foreign samples.

• Food Science and Preservation
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• v.4 no.3
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• pp.295-300
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• 1997

The water extract of mustard seed was fractionated by solvents with an increase of polarity, and antimicrobial activities of each extracts were examined, and volatile compounds of each extract were identified by GC-MS. When the water extract was fractionated with solvents, the antimicrobial activities were high in the order of chloroform, ethylacetate, hexane, butanol and aqueous layer. In chloroform fraction, 16 volatile compounds, including 2 isothiocyanates such as 3-isothiocyanato- 1-propene and 4-isothiocyanato- 1-butane, 1 nitrile and 4 acids were identified, their contents were higher than other fractions. Twelve, 10, 4 and 7 volatile compounds were identified in ethylaceate, hexane, butanol and water fractions, respectively. The volatile compounds were considerably less in the fractions of butanol and water than others.