• Natural Product Sciences
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• v.18 no.1
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• pp.8-12
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• 2012

An anacardic acid analog (1) was isolated from the fungus Paecilomyces variotii which was derived from the giant jellyfish Nemopilema nomurai. Compound 1 was isolated from a natural source for the first time and was evaluated for antibacterial activity against human and marine pathogens, including MDR (multidrugresistant) strains. Compound 1 exhibited mild antibacterial activity against Escherichia coli DC 2, Streptococcus iniae, and methicillin-resistant Staphylococcus aureus 3089 (MRSA).

• Korean Journal of Microbiology
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• v.12 no.2
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• pp.77-84
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• 1974

In order to study 5-nitro-2-furaldehyde derivatives having more effective antibacterial activity, four new $N^4$-(5-nitro-2-furfurylidene)-$N^1$-substituted sulfanilamides$N^1$-3,4-dimethyl-5-isoxazoyl-$N^4$-5-nitro-2-furfurylidene sulfanilamide, $N^1$-4,6-dimethyl-2-pyrimidyl-$N^4$-5-isoxazoyl-$N^4$-5-nitro-2-furfurylidene sulfanilamide, $N^1$-6-methoxy-3-pyridazinyl-$N^4$-5-nitro-2-furaldehyde with sulfa drugs such as sulfisoxazole, sulfamethazine, sulfamethoxypyridazine, and sulfadimethoxine. All compounds were tested for antibacterial activity in vitro on the following micro-organisms : Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Proteus vulgaris. Each compound exhibited a fair bacteriostatic activity against each microorganism. Above all, sulfisoxazole derivatives showed higher activity than the others. Each compound was most active against Staphylococcus aureus, whereas least active against proteus vulgaris.

• Ocean and Polar Research
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• v.42 no.1
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• pp.15-20
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• 2020

The marine sponge Hyrtios sp. collected in the Philippines was extracted and partitioned. The resulting organic layer was purified by C₁₈ reversed-phase column chromatography and HPLC to achieve the separation of nine scalarane-type sesterterpenes, including one new compound with eight known scalarane analogs. The chemical structures of the isolated compounds 1-9 were elucidated by 1D and 2D NMR and MS data analysis. All nine compounds were evaluated for their antibacterial activities against three Gram-positive and three Gram-negative bacteria. The compound 3 exhibited potent antibacterial activities against Bacillus subtilis and Micrococcus luteus. The compounds 7 and 9 displayed considerable activities against Bacillus subtilis and the others had moderate results.

• Korean Journal of Pharmacognosy
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• v.23 no.4
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• pp.240-247
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• 1992

Impatiens balsamina Linne(Balsaminaceae) known as 'BONG SUN HWA' in Korea and has been used for the treatment of scrofulosis, carbunculus and dysenteria etc. Bioassay-guided fractionation of MeOH extract from the whole plants of Impatiens balsamina has afforded a simple naphthoquinone derivative, 2-methoxy-1,4-naphthoquinone. The structure of this compound was established by spectroscopic methods. This compound possessed strong antifungal activity against Candida albicans, AspergiIlus niger, Crytococcus neoformans and Epidermophyton floccusum. The activity of 2-methoxy-1,4-naphthoquinone on E. floccusum $(MIC{\;}:{\;}5.0{\;}{\mu}g/ml)$ was the same potency as that of nystatin. It showed also strong antibacterial activity against gram-positive bacteria Bacillus subtilis as well as gram-negative bacteria Salmonella typhimurium. Although the activity of this compound on gram-negative bacteria was lower than that of gram-positive bacteria.

• Textile Coloration and Finishing
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• v.14 no.1
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• pp.11-17
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• 2002

To identify the antimicrobial activity, of tumeric and its active compound tumeric was fractionated into four groups dichloromethane extract, hexane fraction, methanol soluble fraction and residue's extract. They were tested for antibacterial activity against E. coil and S. aureus and the methanol soluble fraction was found lo be the most active fraction. Compound I, II and III were isolated from TLC and silica gel column chromatography in the methanol soluble fraction. These compounds were analyzed by $^1H-NMR\;and\;^{13}C-NMR$ spectra and identified as curcumin I, II and III. They were also tested for antimicrobial activity against E. coli and S. aureus. Curcumin I was the must active curcuminoids due to the phenolic and methoxyl$(OCH_3)$ moiety in the same molecular structure.

• Natural Product Sciences
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• v.21 no.3
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• pp.147-149
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• 2015

Two terpenoids, including one uniquely aromatized one (1), were isolated from CH₂Cl₂-soluble fraction of MeOH extracts of Curcuma zedoaria. They were identified to be a sesquiterpene ketolactone (1) and orobanone (2), respectively on the basis of their NMR data. The structure of compound 1 was confirmed by X-ray chrystallography and the reported NMR assignments for 1 were revised in this study. Antibiotic activities for compounds 1 and 2 were evaluated using disk diffusion assay. Compound 1 showed potent antibacterial activities against Listeria monocytogenes and Staphylococcus pseudointermedius while compound 2 was active against Bacillus cereus.

• Natural Product Sciences
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• v.22 no.3
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• pp.216-219
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• 2016

The microbial transformation of anthranilic acid (1) by the marine-mudflat-derived fungus Thielavia sp. produced an antibacterial polycyclic quinazoline alkaloid, thielaviazoline (2). The stereostructure of the metabolite was assigned based on detailed spectroscopic data analyses including comparison of the NMR ($^1H$ and $^{13}C$) data with those of reported compound (2). Compound 2 displayed in vitro antimicrobial activity against methicillin-resistant and multidrug-resistant Staphylococcus aureus (MRSA and MDRSA), with minimum inhibitory concentrations (MICs) of 6.25 and $12.5{\mu}g/mL$, respectively. Compound 2 also showed potent radical-scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) with an $IC_{50}$ of $11{\mu}M$, which was more active than the positive control, L-ascorbic acid ($IC_{50}$, $20.0{\mu}M$).

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.13-18
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• 2014

Bacillus subtilis JW-1 was isolated from rhizosphere soil as a potential biocontrol agent of bacterial wilt caused by Ralstonia solanacearum. Seed treatment followed by a soil drench application with this strain resulted in >80% reduction in bacterial wilt disease compared with that in the untreated control under greenhouse conditions. The antibacterial compound produced by strain JW-1 was purified by bioactivity-guided fractionation. Based on mass spectroscopy and nuclear magnetic resonance spectral data ($^1H$, $^{13}C$, $^1H-^1H$ correlation spectroscopies, rotating frame nuclear Overhauser effect spectroscopy, and heteronuclear multiple-bond correlation spectroscopy), the structure of this compound was elucidated as a cyclic lipopeptide composed of a heptapeptide (Gln-Leu-Leu-Val-Asp-Leu-Leu) bonded to a ${\beta}$-hydroxy-iso-hexadecanoic acid arranged in a lactone ring system.

• YAKHAK HOEJI
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• v.30 no.1
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• pp.24-30
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• 1986

New antibiotics having moieties of penicillanic acid, cephalosporanic acid and ampicillin on both ends of the central alkylene were synthesized by reacting 6-aminopenicillanic acid (6-APA), 7-aminocephalosporanic acid (7-ACA) and ampicillin with hexamethylene diisocyanate and sebacoyl chloride, respectively. Antibacterial activities of the compounds were also investigated. The compound derived from sabacic acid and ampicillin exhibited an enhanced antibacterial activities against gram-negative bacteria and was found to be a promising wide-spectrum antibiotic.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.498-503
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• 2005

Antibacterial activities of water and 70% ethanol extracts of Terminalia chebula Retz were investigated. Fractions were prepared by step-wise fractionation of water and 70% ethanol extracts using acetone, hexane, chloroform and butanol. Butanol fraction showed best antibacterial activities. Water and 70% ethanol extracts of T. chebula Retz. had significantly high pyrogallol content among 13 phenolic compound analysed by HPLC, and pyrogallol (standard) showed highest activities against several food spoilage microorganism.