• Microbiology and Biotechnology Letters
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• v.19 no.3
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• pp.235-241
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• 1991

- A phthalic acid derivative and basic macrolide antibiotics, with antimicrobial activity against Gram positive bacteria and phytopathogenic fungi, respectively, were found to be produced by a strain 88-GT-161 identified as being a variety of Streptomyces melanosporofaciens. This paper describes an isolation procedure of the active compounds produced by this strain, their in vitro and in vivo (pot test) antimicrobial activites, and structure determination of one of the compounds, bis (2-ethylhexyl) phthalate, a phthalic acid derivative antibiotic. This compounds, upon cornparision with authentic bis (2-ethylhexyl) phthalate, dioctyl phthalate, revealed a difference in antimicrobial activity even though physico-chemical properties of these two compounds seemed indentical. This is the first report that dioctyl phthalate is biosynthetically produced by a Streptomyces sp. and shows antimicrobial activity.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.240-241
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• 2001

자연계로부터 Vibrio sp.에 항균활성을 갖는 균을 검색하여 분리하고 분리균의 동정결과 Pseudomonas aeruginoso로 동정되었으며, 분리한 균의 항균성 물질의 최적 생산조건을 검토하며, 항균성 물질을 정제하여 그 안정성과 항균작용기작에 대해 조사한 결과 pH와 열에 대한 광범위한 안정성을 보였으며, 항균물질이 V. cholerae non-O1 ATCC 25872 세포에 대해 뚜렷한 용균작용을 하는 것을 관찰하였다.

• Research in Plant Disease
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• v.21 no.1
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• pp.12-19
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• 2015

Antimicrobial activities of nano-materials were tested against several plant pathogens. Twelve different nano-materials were used to observe the antagonistic activity against three kinds of mold and sixteen different kinds of watermelon fruit rot pathogens (Acidovorax citrulli). According to the results, no antagonism have been found against the pathogen, Cylindrocarpon destructans. However in the case of Pythium ultimum, combination of Brass/Glucose 1,000 ppm confirmed the mycelial growth reduction by 94%. In addition, little effect was found against Rhizoctonia solani by Ag/Glucose 3,000 ppm. The remaining other nano-materials have different antimicrobial effect depending on the strains of A. citrulli. But in the case of lime (Cu/Salt 1,000 ppm) highest antimicrobial activity was observed with 97%. Moreover growth of five different strains of A. citrulli was checked by 99% with the combination of Ag/Glucose 1,000 ppm. 92% reduction of A. citrulli growth was observed with $Brass/CaCO_3$ 3,000 ppm. Tested nano-materials against different plant pathogens in this study showed the antimicrobial activity at the range of 24-70%.

• Journal of Animal Science and Technology
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• v.48 no.4
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• pp.595-602
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• 2006

The purpose of this study is to demonstrate antimicrobial activities of the lactoferrin and its peptic hydrolysates obtained from the colostrums of Hanwoo(Korean native cattle) and Holstein cattle. In the measurement of antimicrobial activity to E. coli O111 and other microorganisms, bovine lactoferrin showed a higher antimicrobial activity than that of Hanwoo cow's lactoferrin . The minimal inhibitory concentration (MIC) of lactoferrin against E. coli O111 was exhibited 1.5mg/ml(Holstein) and 2.75mg/ml (Hanwoo). The same result was also observed between bovine lactoferrin hydrolysate (0.12mg/ml) and Hanwoo cow's lactoferrin hydrolysate (0.25mg/ml). In addition of lysozyme, antimicrobial activity of lactoferrin was increased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.5
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• pp.1344-1348
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• 2008

Anti-microbial activities of Scutellariae Radix Extracts and Sophora flavecens Extracts was tested by formulation, such as skinsoftener, emulsion for 4 weeks. Control contained no preservative, test group contained 1.00% Scutellariae Radix extracts and 1.00% Sophora flavecens extracts and positive control contained parabens and imidazolidinyl urea. To determine the anti-microbial activity of these extract, the 4 germs such as Escherichia coil, Pseudomonas aeruginosa, Staphylococcus aures, Canida albicans were used. The test groups showed significant anti-microbial activities against the 4 germs at 2 and 3 weeks as compared with control. Anti-microbial activities of these extracts were similar to positive control. Considering that the Scutellariae Radix Extracts and the Sophora flavecens Extracts have a significant anti-microbial activities against 4 germs, it is possible as natural preservative in cosmetics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1116-1122
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• 2000

천연 식품보존료 개발의 일환으로 우리 나라에서 옛부터 조미료 및 향신료 등으로 널리 이용되고 초피를 가시 있는것과 없는 것으로 구분하여 이들의 잎, 과피 및 종실을 대상으로 물과 에탄올로 항균성 물질을 추출하여 수종의 병원균과 식중독균, 식품과 관련이 있는 세균 및 효모 줄 10균주들에 대하여 항균성이 있는지의 여부를 관찰하였으며, 항균성이 강한 에탄올추출물의 초소저해농도, 추출물에 함유된 항균성물질의 열안전성, pH안정성 등을 조사하였다. 초피와 민초피의 항균활서은 tkdydd된 10균주 중 젖산균과 효모를 제외한 대부분의 세균에서 잎과 과피에서 물과 에탄올추출물 모두에서 항균활성이 나타났으나 종실에서는 항균활성을 보이지 않았다. 초피 에탄올추출물의 최소저해농도는 Bacillus cereus 균주가 0.25mg/mL로 가장 낮게 나타났으며, 젖산균과 효모에서는 항균활성 물질은 121$^{\circ}C$에서 15분간 가열한 후에도 활성이 유지되었으며, pH의 변화에도 영향을 받지 않았다.

• Journal of agriculture & life science
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• v.43 no.3
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• pp.15-26
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• 2009

This study was undertaken to determine inhibitory compounds from extracts of the softwood (larix leptolepis, Pseudotsuga menziesii) sawdust against Trichoderma spp. The sawdust of L. leptolepis and P. menziesii were hot water extracted, which were with fraction extracted organic solvents. The organic solvent extractions were carried out by n-hexane, methylene chloride, ethyl acetate. The antifungal activity of hot water extracts of L. leptolepis sawdust was determined to be 20.6% inhibition at a concentration of 1,000 ppm against Trichoderma spp. The antifungal activity of P. menziesii sawdust was outstanding about 60.3% against Trichoderma spp. The yields of the fractions of n-hexane soluble, methylene chloride soluble and ethyl acetate soluble from the hot water extract of L. leptolepis sawdust were 4.0%, 6.0% and 8.0%, repectively. However, the yields of the fractions of three solvents of P. menziesii sawdust were 8.0%, 13.0 and 14.0% correspondingly. The antifungal activity of n-hexane soluble fraction from hot water extracts of L. leptolepis sawdust was highest to about 68.5% to 79.9% against Trichoderma spp. compared to others. The antifungal activities of n-hexane soluble fraction from hot water extracts of P. menziesii sawdust showed 68.5%, 71.4%. 71.9%, 75.7% and 82.3% against T. aggressivum, T. atroviride, T. harzianum, T. koningii and T.viride, respectively. The n-hexane soluble fraction revealed much higher antifungal activity than the other fractions did. This study demonstrated that the n-hexane fraction of the hot water extracts of L. leptolepis and P. menziesii exhibited the greatest antifungal activity against Trichoderma spp.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.177-183
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• 2002

The extracts from approximately 40 different Korean traditional medicines were prepared to investigate the antimicrobial activities against poultry disease-related bacteria. Among tested, the extracts of Schizandra chinensis (SC), Melia azedarach (MA), Caesalpinia sappan (CS) and Rhus javanica (RJ) exhibited significant antimicrobial activities against Salmonella gallinarum, whereas the extracts of Elsholtzia ciliata (EC), Myristica fragrans (MF), Alpinia katsumadai (AK), Poncirus trifoliata (PT), Prunella vulgaris (PV), CS and RJ exhibited antimicrobial activities against Staphylococcus aureus. Minimum inhibitory concentrations (MIC) of MA, CS and RJ extracts against S. gallinarum were 1.2 mg/ml, whereas MIC of RJ extract for S. aureus was 0.6 ㎎/ml, which was the lowest among tested. The antimicrobial activities of SC and RJ extracts against S. gallinarum were reduced, but those of AK and CS extracts against S. aureus were not affected by heating treatment. The antimicrobial activities of SC extract against S. gallinarum and those of EC, PT and RJ extracts against S. aureus were stable by acid treatment but unstable by alkaline treatment. those of CS extract was not effected by either acid or alkaline treatment. The growth of all bacteria was significantly inhibited within 24 hours by the addition of at least 100 ppm and 300 ppm of RJ and CS extracts, respectively, compared with the control group. In conclusion, these findings suggest that RJ and CS extracts may play important roles for antimicrobial activities against poultry disease-related bacteria.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.665-670
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• 2018

This study was designed to evaluate the physicochemical properties and biological activities (antioxidant activity and antimicrobial activities) of three and seven-year-old Platycodon grandiflorum extracts. Three and seven-year-old Platycodon grandiflorum contained crude saponins, free amino acids and minerals. Water extracts of the three and seven-year-old plants were prepared using reflux extraction methods. The total polyphenol contents (TPC), total flavonoid contents (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity and antimicrobial effects of the extracts were determined. The seven-year-old Platycodon grandiflorum extract had higher TPC ($5.08{\pm}0.07TAEmg/g$) and TFC ($3.80{\pm}0.07QUEmg/g$). DPPH radical scavenging activity ($IC_{50}$ value: $288{\pm}3.88{\mu}g/mL$) and ABTS radical scavenging activity ($IC_{50}$ value: $568{\pm}2.09{\mu}g/mL$). The three and seven-year-old Platycodon grandiflorum extracts exhibited a strong antimicrobial effect against three kinds of bronchus disease-inducing bacteria; the seven-year-old Platycodon grandiflorum extracts showed a stronger antimicrobial effect than the three-year-old Platycodon grandiflorum extracts.

• Journal of Life Science
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• v.31 no.1
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• pp.83-89
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• 2021

Uu-ilys, an i-type lysozyme from spoon worm (Urechis unicinctus), is an innate immune factor that plays an important role in the defense against pathogens. It also possesses non-enzymatic antibacterial activity. Thus, there is a possibility to develop an antimicrobial model peptide from Uu-ilys. In this study, we report the design, production, and antibacterial activity of an Uu-ilys analog that exhibits antibacterial activity. The Uu-ilys structure was fragmented according to its secondary structures to predict the regions with antimicrobial activity using antimicrobial peptide (AMP) prediction tools from different AMP databases. A peptide containing the C-terminal fragment was predicted to exert antimicrobial activity. The chosen fragment was designated as an Uu-ilys analog containing the C-terminal fragment, Uu-ilys-CF. To examine the possibility of developing an AMP using the sequence of Uu-ilys-CF, recombinant fusion protein (TrxA-Uu-ilys-CF) was produced in an expression system that was heterologous. The produced fusion protein was cleaved after methionine leaving Uu-ilys-CF free from the fusion protein. This was then isolated through high performance liquid chromatography and reverse phase column, CapCell-Pak C18. The antibacterial activity of Uu-ilys-CF against different microbial strains (four gram-positive, six gram-negative, and one fungal strain) were assessed through the ultrasensitive radial diffusion assay (URDA). Among the bacterial strains tested, Salmonella enterica was the most susceptible. While the fungal strain tested was not susceptible to Uu-ilys-CF, broad spectrum antibacterial activity was observed.