• Journal of Microbiology and Biotechnology
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• 제22권9호
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• pp.1214-1217
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• 2012

One Helicosporium strain, isolated from a wilted chestnut tree, evidenced in vitro antimicrobial activity against various types of bacteria and fungi, and generated a diffusible pigment. The antimicrobial compounds and the diffusible pigment of the Helicosporium sp. isolate were purified via solvent fractionation, column chromatography, and recycling preparative chromatography. Both the major antimicrobial compound and the diffusible pigment were identified as 2-methylresorcinol via nuclear magnetic resonance spectroscopy. Therefore, 2-methylresorcinol, a diffusible pigment generated by Helicosporium sp., appears to be an active antimicrobial principle. This pigment also exhibited considerable cytotoxicity against mammalian cells.

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2338-2343
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• 2007

Under the framework of green chemistry, an efficient and extremely fast procedure for the synthesis of 5a-h through four-step procedure starting from 2-arylidenetetralin-1-one 1a-d under microwave irradiation is described. A considerable increase in the reaction rate has been observed with better yield. The structures of the synthesized compounds have been characterized on the basis of their elemental analysis and spectral data. Synthesized compounds 5a-h was evaluated for their antimicrobial activity. Some of the compounds exhibited appreciable activity.

• 약학회지
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• 제43권3호
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• pp.306-315
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• 1999

To develop new cephalosporin antibiotics with improved antibacterial activities, a series of 7$\beta$-[2-(2-aminothiazol-4-y)-(Z)-2-(1-carboxy-1-methylethoxyimino)acetamido] -3-[5-(heterocycle)thiomethylpy-rrolidin-3-ylthio]methyl-3-cephem-4-carboxylic acid (14~18) having aminothiazol carboxymethylethoxy-imino group on the C-7 position and (heterocycle) thiomethyl pyrrolidinthiomethyl group on the C-3 position of the cephem ring were synthesized. These compounds were tested for antimicrobial activity in vitro against Gram(+) and Gram(-) bacteria. Compounds 15 and 16 showed remarkable antibacterial activity against Salmonella typhimurium TV119 and Alcalienes faecalis KCTC1004, but most of compounds showed lower activity than cefotaxime.

• 대한화학회지
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• 제58권1호
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• pp.62-67
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• 2014

In the present study a novel series of (2-substituted-4-methylthiazol-5-yl)(4-substituted piperazin-1-yl)methanone derivatives were synthesized by reaction of 2-substituted-4-methylthiazole-5-carboxylic acid with N-substituted benzyl piperazine by using 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride (EDCl) and 1-hydroxybenzotriazole (HOBt) in DMF. All the newly synthesized compounds were characterized by spectral methods. The title compounds were screened for in vitro antibacterial activity. Most of the compounds show moderate to good antimicrobial activity.

• 대한화학회지
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• 제57권2호
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• pp.221-226
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• 2013

A series of some novel 2-[5-(substituted phenyl)-[1,3,4]oxadiazol-2-yl]-benzoxazoles were synthesized by using benzoxazole-2-carboxylic acid on reaction with thionyl chloride in presence of ethanol solvent at room temperature gave benzoxazole-2-carbonyl chloride, which is turned into benzoxazole-2-carboxylic acid hydrazide on reaction with hydrazine hydrate in ethanol solvent under reflux. The subsequent treatment of benzoxazole-2-carboxylic acid hydrazide with an appropriate aromatic carboxylic acid in presence of polyphosparic acid under reflux afforded the title compounds. The chemical structures of the newly synthesized compounds were elucidated by their IR, $^1H$ NMR and Mass spectral data analysis. Further the compounds are used to find out their ability towards anti microbial and nematicidal activity.

• Archives of Pharmacal Research
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• 제22권2호
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• pp.194-201
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• 1999

The reaction of thiocyanoacetamide (1) with ${\alpha},{\beta}$-unsaturated ketones 2a,b resulted in the formation of the corresponding newly synthesized 1(H)-pyridinethione derivatives 3a,b. Compounds 3a,b were used as synthons for the preparation of 2-S-alkyl-, 2-S-acetamidopyridine, thieno[2,3-b]pyridine and pyrazolo[3,4-b]pyridine derivatives via a wide range of reactions with different reagents. The antimicrobial activity of some of the newly synthesized compounds was tested. Compounds 3a, 11a, 15a, and 19a,b were found to be the most active ones.

• Journal of Microbiology and Biotechnology
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• 제33권4호
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• pp.543-551
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• 2023

In this study, five endophytic fungi belonging to the Aspergillus and Alternaria genera were isolated from Lagopsis supina. The antimicrobial activity of all fungal fermented extracts against Staphylococcus and Fusarium graminearum was tested using the cup-plate method. Among them, Aspergillus ochraceus XZC-1 showed the best activity and was subsequently selected for large-scale fermentation and bioactivity-directed separation of the secondary metabolites. Four compounds, including 2-methoxy-6-methyl-1,4-benzoquinone (1), 3,5-dihydroxytoluene (2), oleic acid (3), and penicillic acid (4) were discovered. Here, compounds 1 and 4 displayed anti-fungal activity against F. graminearum, F. oxysporum, F. moniliforme, F. stratum, Botrytis cinerea, Magnaporthe oryzae, and Verticillium dahlia with diverse MIC values (128-512 ㎍/ml), which were close to that of the positive control antifungal, actidione (64-128 ㎍/ml). Additionally, compounds 1 and 4 also exhibited moderate antibacterial activity against S. aureus, Listeria monocytogenes, Escherichia coli, and Salmonella enterica, with low MIC values (8-64 ㎍/ml). Moreover, compounds 1 and 4 displayed selective cytotoxicity against cancer cell lines as compared with the normal fibroblast cells. Therefore, this study proposes that the endophytic fungi from L. supina can potentially produce bioactive molecules to be used as lead compounds in drugs or agricultural antibiotics.

• Natural Product Sciences
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• 제13권4호
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• pp.279-282
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• 2007

The aim of the present study was to investigate the various chemical components present in the cone volatile oil of Cupressus macrocarpa and also determine its antimicrobial activity. Totally 13 compounds were identified with 99.99% by GC-MS analysis. The major compounds identified were terpinene-4-ol (19.42%), dinopol (15.63%), ${\alpha}$-pinene (13.58%), and ${\beta}$-pinene (12.16%). The antimicrobial activity was carried out for the oil and a 2% cream formulation using cup plate method by measuring the zone of inhibition. The gram positive organisms used were Bacillus subtilis, Staphylococcus aureus, Bacillus megaterium, and Bacillus cogulans. The gram negative organisms used were Escherichia coli, Kleibseilla pneumonia, Pseudomonas aeruginosa and Salmonella typhi. In vitro antifungal studies were also carried out by using organisms, Candida albicans, Aspergillus flavus, Trichoderma lignorum and Cryptococcus neoformans. The standard drugs used were penicillin ($100{\mu}g/mL$), gentamycin ($100{\mu}g/mL$) and griseofulvin ($100{\mu}g/mL$) for gram positive bacteria, gram negative bacteria and fungi respectively. Both oil and cream formulation showed good activity against fungi than bacteria. This study is being reported for the first time on cone volatile oil of this plant.

• The Korean Journal of Ecology
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• 제22권1호
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• pp.51-58
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• 1999

자생식물과 귀화식물을 대상으로 allelochemicals를 분석하고 그 항균효과를 조사하였다. 자생식물과 귀화식물 추출액 간의 가용성 고형물 함량에는 차이를 보이지 않았고 자생식물인 까마중의 가용성 고형물 함량이 90 mg/ml로 가장 높게 나타났다. 자생식물의 에탄을 추출액에 의한 Aspergillus phoenicis KCTC 1228의 항균력은 까마중에서만 나타났으며 clear zone이 18 mm였고 포자형성은 억제되었다. 귀화식물 중 돼지풀과 망초에서 포자형성이 억제되면서 clear zone이 24 mm와 22 mm로 형성되었고 미국자리공과 원추천인국은 포자가 형성되면서 clear zone이 22 mm와 19 mm로 나타났다. 자생식물인 까마중과 귀화식물인 미국자리공과 돼지풀에서 토양미생물인 Bacillus sphiaericus 2362와 Bacillus sphiaericus 2291, Bacillus thuringiensis var. subtilis와 Bacillus thuringiensis var. cereus에서 항균력이 나타났는데 돼지풀이 각 균주에서 항균활성이 가장 크게 나타났다. 특히 Bacillus thuringiensis var. subtilis에서 clear zone이 32 mm로 활성이 강하게 조사되었다. 일반적으로 추출액내의 가용성 고형물 함량이 높을수록 항균 활성이 크게 나타남을 알 수 있다. 자생식물인 까마중과 귀화식물인 미국자리공과 돼지풀의 추출액을 HPLC로 성분분석한 결과 까마중은 hydroquinone외 3종이, 미국자리공은 cinnamic acid외 5종이, 돼지풀은 benzoic acid외 7종이 분석되었다. Phenolic compound 각각에 대한 Aspergillus phoenicis KCTC 1228에 대한 항균력은 coumaric acid와 benzoic acid에서 조사되었다.

• 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.