• Bulletin of the Korean Chemical Society
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• v.28 no.12
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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.

• YAKHAK HOEJI
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• v.43 no.3
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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.

• Journal of the Korean Chemical Society
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• v.58 no.1
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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.

• Journal of the Korean Chemical Society
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• v.57 no.2
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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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• v.22 no.2
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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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• v.33 no.4
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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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• v.13 no.4
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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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• v.22 no.1
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• pp.51-58
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• 1999

Korean native plants and naturalized plants were analyzed for allelochemicals, and their antimicrobial effects were studied. The difference in soluble solid contents between Korean native plants and naturalized species was not significant, and the Korean native plant, Solanum nigrum showed the highest soluble solid content of 90 mg/ml. The ethanol extract of the Korean native plant, Solanum nigrum showed antifungal activity to Aspergillus phoenicis KCTC 1228, with a clear zone of 18 mm, and spore formation was not observed from the treatment. The naturalized plants Ambrosia artemisiifolia var. elatior and Erigeron canadensis showed inhibition of spore formation and the clear zones were at 24 mm and 22 mm, respectively. The clear zones of Aspergillus phoenicis KCTC 1228 treated with ethanol extrats of Phytolacca americana and Rudbeckia bicolor were 22 mm and 19 mm, respectively, and spore formation was observed from the treatment. The Korean native plant, Solanum nigrum and naturalized plants, Phytolacca americana and Ambrosia artemisiifolia var. elatior showed antimicrobial activity against Bacillus sphiaericus 2362, and Bacillus sphiaericus 2297, Bacillus thuringiensis var. subtilis and Baicillus thuringiensis var. cereus. The antimicrobial activity of Ambrosia artemisiifolia var. elatior showed the largest clear zone of 32 mm against Bacillus thuringiensis var. subtilis. In general, the more soluble the solid contents of the extracts, the greater were the antifungal and antimicrobial activities. The phenolic compounds from the Korean native plant, Solanum nigrum and the naturalized species, Phytolacca americana and Ambrosia artemisiifolia var. elatior were analyzed by high performance liquid chromatography. Three phenolic compounds including hydroquinone were identified in Solanum nigrum. In contrast, five and seven phenolic compounds were identified in Phytolacca americana and Ambrosia artemisiifolia var. elatior, respectively. The antifungal activity against Aspergillus phoenicis KCTC 1228 was found to be due to the coumaric and benzoic compounds.

• Journal of Microbiology and Biotechnology
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• v.20 no.2
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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.

• Korean Journal of Veterinary Research
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• v.54 no.3
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• pp.159-164
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• 2014

Bacterial infection of the uterus in Hanwoo can kill embryos. Therefore, many antibiotics have been used to treat this infection in the uterus of repeat breeders. Incorrect use of antibiotics has led to resistance in bacteria. Natural compounds have used as substitutes for antibiotics because they are safe and have very mild side effects. This study was conducted to examine the antimicrobial effects of five extracts from medicinal plants including Humulus japonicas (Hj), Phelledendron amurense (Pa), Viola mandshurica (Vm), Carthamus tinctorius (Ct), and Chelidoni herba (Ch) on bacteria isolated from the uterus of Hanwoo using the paper disc diffusion method. Hj and Pa extracts had potent antimicrobial effects against Staphylococcus lentus, Streptococcus infantarius subsp. coli, and Bacillus pumilus. Pa had the greatest antimicrobial effect among the five medicinal plants and was effective against 19 types of bacteria from bovine uterus. Compared to Pa, Hj showed weaker antimicrobial effects on all the bacteria tested except Pseudomonas aeruginosa. Vm, Ct, and Ch also showed weak antimicrobial effects on the tested bacteria. The results obtained suggest that Hj and Pa are natural compounds suitable for treating bacterial infection in repeat breeders and improving conception rates of Hanwoo.