• 미생물학회지
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• 제43권3호
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• pp.227-231
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• 2007

구강청정제에 사용되는 많은 항미생물 성분들은 치주조직의 착색 및 작열감 등의 부작용을 가지고 있다. 이러한 취약점을 해결하고, 좀 더 생체친화적인 항미생물 물질을 찾기 위하여,한국식물추출물은행에서 소장하고 있는 2,125종의 식물추출물을 검색하였다. 항미생물 능력을 확인하기 위해, 잘 알려진 치과 병원균(치주질환 3종, 충치 1종)에 대한 성장억제 효과를 측정하였다. 대표적인 치주질환 유발세균인 Porphyromonas gingivalis에 대해서 19중의 식물 추출물이 항생효과를 나타내었으며, 17종이 Prevotella intermedia에 대해, 45종이 Haemophilus actinomycetemcomitans에 대해, 그리고 85종의 추출물이 충치 유발세균인 Streptococcus mutans 에 대해 효과를 나타내었다. 이중에서 총8종의 식물추출물이 실험에 사용한4종의 미생물 중 3종 이상에 대해 항생작용을 나타내었다. 또한 Cudrania tricuspidata, Morus bombycis와 Mallotus japonicas가 실험에 사용된 4종의 치과 병원균 모두에 대해 항생작용을 나타내어 치과용 재료 혹은 양치액에 항미생물 물질로 사용될 가능성을 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제29권7호
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• pp.1144-1154
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• 2019

There have been several studies regarding lichen-associated bacteria obtained from diverse environments. Our screening process identified 49 bacterial species in two lichens from the Himalayas: 17 species of Actinobacteria, 19 species of Firmicutes, and 13 species of Proteobacteria. We discovered five types of strong antimicrobial agent-producing bacteria. Although some strains exhibited weak antimicrobial activity, NP088, NP131, NP132, NP134, and NP160 exhibited strong antimicrobial activity against all multidrug-resistant strains. Polyketide synthase (PKS) fingerprinting revealed results for 69 of 148 strains; these had similar genes, such as fatty acid-related PKS, adenylation domain genes, PfaA, and PksD. Although the association between antimicrobial activity and the PKS fingerprinting results is poorly resolved, NP160 had six types of PKS fingerprinting genes, as well as strong antimicrobial activity. Therefore, we sequenced the draft genome of strain NP160, and predicted its secondary metabolism using antiSMASH version 4.2. NP160 had 46 clusters and was predicted to produce similar secondary metabolites with similarities of 5-100%. Although NP160 had 100% similarity with the alkylresorcinol biosynthetic gene cluster, our results showed low similarity with existing members of this biosynthetic gene cluster, and most have not yet been revealed. In conclusion, we expect that lichen-associated bacteria from the Himalayas can produce new secondary metabolites, and we found several secondary metabolite-related biosynthetic gene clusters to support this hypothesis.

• Applied Biological Chemistry
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• 제46권3호
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• pp.262-267
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• 2003

밤나무의 밤꽃과 밤잎의 항균활성 효과를 조사하기 위하여, 시료를 80% methanol로 추출하여 용매분획을 하였다. 용매분획별 수율은 밤꽃에서 ethylacetate 1.94%, methanol 4.75% 및 water 7.81%였고, 밤잎은 ethylacetate 2.24%, methanol 5.03% 및 water 8.47%였다. 밤꽃과 밤잎의 methanol 분획 추출물은 Gram양성 및 음성의 모든 균주에서 강한 항균활성을 보였으며, ethylacetate 및 water 분획 추출물은 약한 항균활성을 보였다. 최소저해농도는 $60\;{\mu}g/disc$ 이상에서 항균력이 인정되었다. Bacillus. subtilis에 대한 생육저해 효과는 control에 비하여 밤꽂과 밤잎 추출물은 모두 낮은 생육저해 효과를 보였으며, 또한 각 추출물은 모두 배양 15시간까지는 현저히 낮은 생육저해를 보이다가 그 후는 약간 높아졌다. 밤꽃 추출물에서는 methanol 추출물이 가장 높은 생육저해효과를 보인 반면에, water 추출물은 다른 추출물에 비하여 낮은 생육저해를 보였으며, 밤잎 추출물은 각 추출물에서 거의 비슷한 생육저해를 보였다. 밤꽃과 밤잎의 methanol 분획 추출물을 B. subtilis에 각각 500 ppm씩 처리한 후, 주사전자현미경(SEM)으로 관찰한 결과, 추출물을 처리하지 아니한 경우는 전형적인 Bacilli의 형태를 보였지만, methanol 분획추출물을 처리한 경우는 세포의 형태가 일그러지고 손상을 입은 형태를 보였다.

• 한국식품위생안전성학회지
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• 제8권3호
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• pp.141-145
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• 1993

수종의 병원성 미생물에 대한 39여종의 생약 열수추출액의 항균성을 조사한 결과 다음과 같은 결과를 얻었다. 황백 Phellodendron amurense 및 황령 Coptis chinensis 는 Staphylococcus aureus균의 생육을 억제시켰으며 복분자 Rubus creanus는 Staphylococcus aureus 및 Pseudomonas aeruginosa에 항균력을 나타내었다. 진피 Citrus unshiu는 E.coli에 대해서 산수유 Cornus officinalis는 Candida albicans의 생육을 억제시켰고 우슬 Achyranthes japonica 및 감초 Clycyrrhiza uralsis는 Aspergillus niger에 뚜렷한 항균효과를 나타내었다. 또한 감초는 Staphylococcus Aureus, E. coli, Pseudomonas aeruginosa , Aspergillus niger 모두에 항균력을 나타내었다.

• 한국정보통신학회논문지
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• 제16권2호
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• pp.384-389
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• 2012

약용식물로부터 충치예방물질을 개발하기 위하여 우리나라에서 전통적으로 널리 사용되어 왔던 25종류의 약용 식물로부터 에탄올 추출물을 분리하였다. 이를 대상으로 충치 원인균인 Streptococcus mutans ATCC 25175에 대한 항균활성을 나타내는 약용식물을 조사하였다. 황련, 고삼, 감초, 박하, 삼백초등이 S. mutans에 대해 항균활성을 나타냈다. 이 중 황련과 고삼의 에탄올 추출물들은 S. mutans에 대해 강한 항균활성을 나타냈다. 이 결과들을 근거로 하여 황련과 고삼의 추출물들은 S. mutans ATCC 25175에 대한 충치 예방물질로서 가능성이 있음을 나타낸다.

• 동의생리병리학회지
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• 제17권2호
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• pp.476-480
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• 2003

Cornis fructus was extracted by successive extraction and then fractionated with hexane extract to get active fractions. This study was performed to determine the cytotoxic effect of hexane extract from Cornis fructus on NIH 3T3 fibroblasts and cancer cell lines using MTT assay. Hexane extract showed cytotoxic effect against A549, B16 melanoma and MDA-MB-231. Futher fractionation with hexane extract was performed to obtain effective fraction, fraction 3 showed the cytotoxic effect against A549 and MDA-MB-231. In antimicrobial test of each fraction of hexane extract, fraction 5 showed antimicrobial activities against P. putida and P. aeruginosa.

• Advances in Traditional Medicine
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• 제8권1호
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• pp.53-58
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• 2008

The plant Quisqualis indica (Compositae) has ehnopharmcological reputation of being used as a healing agent in Bangladesh. In this study, preliminary screenings were conducted to look at the antimicrobial susceptibility and cytotoxicity of the plant extract. The extractives of the plant were subjected to screening for inhibition of microbial growth by the disc diffusion method. The zones of inhibition demonstrated by the n-hexane, carbon tetrachloride, chloroform and aqueous soluble partitionates of the methanolic extract ranged from 8 - 15 mm, 8 - 18 mm, 12 - 20 mm and 10 - 16 mm, respectively at a concentration of 400 ${\mu}g$/disc. All the extractives were also subjected to brine shrimp lethality bioassay for primary cytotoxicity evaluation. Here, the carbon tetrachloride soluble materials demonstrated the highest cytotoxicity with $LC_{50}$ of 0.826 ${\mu}g$/ml, while n-hexane, chloroform and aqueous soluble partitionates of the methanolic extract revealed the $LC_{50}$ of 1.254, 3.866 and 5.366 ${\mu}g$/ml, respectively. This is the first report of the antimicrobial activity and cytotoxicity Q. indica.

• 한국동물위생학회지
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• 제31권1호
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• pp.129-135
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• 2008

A total of 3,943 samples (beef 698, pork 2,178 and chicken 1,067)were collected from slaughter houses in Daegu from January to December 2006 for analysis of antimicrobial residues. The results were also comparatively analyzed with those carried out from 16 veterinary service laboratories nationwide as a part of national residue program in 2006. The samples from 11 farms (cattle 2, pig 9) were found to exceed the legal limit. Among them 5 were classified as tetracyclines, 3 as $\beta$-lactams, 2 as sulfonamides and 1 as quinolone. Nationally a total of 222 farms (241 cases) were found to violate the residual limits, of which 47.3% were detected by screening test, followed by surveillance (38.3%). Failure to observe withholding periods of antimicrobial drugs after treatment was the most significant cause of the non-compliance.

• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.311-318
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• 2010

Antimicrobial finishing of textiles has been found to be an economical way to prevent (or treat) skin disorders. Hence, this research effort was aimed at elucidating the relationship between the molecular weight (MW) of chitosan and its antimicrobial activity upon six dermal reference microorganisms, as well as the influence of the interactions with cotton fabrics on said activity. Using 3 chitosans with different MWs, as well as two chitooligosaccharide (COS) mixtures, a relevant antimicrobial effect was observed by 24 h for the six microorganisms tested; it was apparent that the antimicrobial effect is strongly dependent on the type of target microorganism and on the MW of chitosan - being higher for lower MW in the case of E. coli, K. pneumoniae, and P. aeruginosa, and the reverse in the case of both Gram-positive bacteria. Furthermore, a strong antifungal effect was detectable upon C. albicans, resembling the action over Gram-positive bacteria. Interactions with cotton fabric resulted in a loss of COS activity when compared with cultured media, relative to the effect over Gram-negative bacteria. However, no significant differences for the efficacy of all the 5 compounds were observed by 4 h. The three chitosans possessed a higher antimicrobial activity when impregnated onto the fabric, and presented a similar effect on both Gram-positive bacteria and yeast, in either matrix. Pseudomonas aeruginosa showed to be the most resistant microorganism to all five compounds.

• Advances in Traditional Medicine
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• 제4권3호
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• pp.197-209
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• 2004

The study was aimed at evaluating the antioxidant and antimicrobial activities of methanol extract of Caesalpinia bonducella leaves (MECB) (Family: Caesalpiniaceae). The effect of MECB on antioxidant activity, reducing power, free radical scavenging (DPPH radical, nitric oxide radical, superoxide anion radical, hydroxyl radical and hydrogen peroxide radical scavenging), total phenolic content and antimicrobial activities were studied. The antioxidant activity of MECB increased in a dose dependent manner. About 50, 100, 250 and 500 g of MECB showed 53.4, 61.2, 69.1 and 76.2 % inhibition respectively on peroxidation of linoleic acid emulsion. Like antioxidant activity, the effect of MECB on reducing power increased in a dose dependent manner. The free radical scavenging activity of MECB was determined by DPPH radical scavenging method. The potency of this activity was increased with increased amount of extract. MECB was found to inhibit the nitric oxide radicals generated from sodium nitroprusside $(IC_{50}\;=\;102.8\;g/ml)$ whereas the $IC_{50}$ value of curcumin was 20.4 g/ml. Moreover, the MECB was found to scavenge the superoxide generated by photoreduction of Riboflavin. MECB was also found to inhibit the hydroxyl radical generated by Fenton reaction, where the $IC_{50}$ value is 104.17 g/ml compared with catechin 5 g/ml, which indicates the antioxidant activity of MECB. The MECB capable of scavenging hydrogen peroxide in a concentration-dependent manner. The amounts of total phenolic compounds were also determined. Antimicrobial activities of MECB were carried out using disc diffusion methods with five Gram positive, four Gram negative and four fungal species. The results obtained in the present study indicate that MECB leaves are potential source of natural antioxidant and antimicrobial agents.