• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.731-738
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• 2019

Endophytic fungi are an important component of plant microbiota, and have the excellent capacity for producing a broad variety of bioactive metabolites. These bioactive metabolites not only affect the survival of the host plant, but also provide valuable lead compounds for novel drug discovery. In this study, forty-two endophytic filamentous fungi were isolated from Ficus elastica leaves, and further identified as seven individual taxa by ITS-rDNA sequencing. The antimicrobial activity of these endophytic fungi was evaluated against five pathogenic microorganisms. Two strains, Fes1711 (Penicillium funiculosum) and Fes1712 (Trichoderma harzianum), displayed broad-spectrum bioactivities. Our following study emphasizes the isolation, identification and bioactivity testing of chemical metabolites produced by T. harzianum Fes1712. Two new isocoumarin derivatives (1 and 2), together with three known compounds (3-5) were isolated, and their structures were elucidated using NMR and MS. Compounds 1 and 2 exhibited inhibitory activity against Escherichia coli. Our findings reveal that endophytic fungi from the rubber tree F. elastica leaves exhibit unique characteristics and are potential producers of novel natural bioactive products.

• Natural Product Sciences
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• 제21권1호
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• pp.49-53
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• 2015

Eight isoflavonoid compounds were isolated from the EtOAc fraction of Maackia amurensis which had shown the highest anti-Helicobacter pylori activity among the fractions, using medium pressure liquid chromatography and recrystallization. Based on the spectroscopic data including $^1H$-NMR, $^{13}C$-NMR, HMBC and MS data, the chemical structures of the isolates were determined to be (-)-medicarpin (1), afromosin (2), formononetin (3), tectorigenin (4), prunetin (5), wistin (6), tectoridin (7) and ononin (8). Anti-H. pylori activity of each compound was evaluated with broth dilution assay. As a result, (-)-medicarpin (1), tectorigenin (4) and wistin (6) showed anti-H. pylori activity. (-)-Medicarpin (1) exhibited the most potent growth inhibitory activity against H. pylori with the minimal inhibitory concentration $(MIC)_{90}$ of $25{\mu}M$, and tectorigenin (4) with $MIC_{90}$ of $100{\mu}M$ ranked the second. This is the first study to show the anti-H. pylori activity of M. amurensis, and it is suggested that the stem bark of M. amurensis or the EtOAc fraction or the isolated compounds can be a new natural source for the treatment of H. pylori infection.

• Mass Spectrometry Letters
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• 제13권4호
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• pp.152-157
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• 2022

Schisandra chinensis and its fruits have been used as a traditional herbal medicine to treat liver dysfunction, fatigue, and chronic coughs. Several in vitro and in vivo studies suggested that dibenzocyclooctadiene lignans present in Schisandra fruits strongly inhibit CYP3A4 activity. However, reports on the inhibitory potential of dietary Schisandra supplements against CYP3A activity are limited despite their increasing consumption as dietary supplements. In this study, we evaluated the CYP3A-inhibitory potential of four dietary Schisandra supplements in human liver microsomes. At a concentration of 0.05 mg/mL, Schisandra supplements from Nature's Way, Swanson, Planetary Herbals, and Only Natural inhibited CYP3A activity by 93.9, 70.8, 33.6, and 24.8%, respectively. Nature's Way, which exhibited the strongest inhibition against CYP3A, had the highest contents of gomisin B and gomisin C, which potently inhibit CYP3A activity. The in vivo pharmacokinetics of this product should be examined to determine whether the clinical relevance of inhibiting CYP3A activity by dietary Schisandra supplementation.

• 약학회지
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• 제50권1호
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• pp.52-57
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• 2006

The activation of cyclin dependent kinase 4 (CDK4) is found in more than half of all human cancers. Therefore CDK4 is an attractive target for the development of a novel anticancer agent. For mass screening of CDK4 inhibitor, we set up in vitro kinase assay for CDK4 activity using a cyclin D1-CDK4 fusion protein, which is constitutively active and exhibits enhanced stability. From the screening of representative compound library of Korea Chemical Bank, we found that 7-chloro-4-nitro-benzo[1,2,5]oxadiazole 1-oxide (FBP-1248) selectively inhibited CDK4 activity in vitro by ATP competitive manner. This compound prevented the phosphorylation of retinoblatsoma tumor suppressor protein, Rb, and inhibited cell growth through cell cycle arrest. In summary, we developed an efficient assay system for CDK4 activity in vitro and identified the CDK4 inhibitory compound, FBP-1248.

• Advances in Traditional Medicine
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• 제7권2호
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• pp.133-140
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• 2007

Anti-tumor activity of Euphorbia hirta (50 mg/kg and 100 mg/kg) has been evaluated against Ehrlich's ascites carcinoma (EAC) in Swiss albino mice. Intraperitoneal (i.p) administration of Euphorbia hirta was effective in reducing solid tumor mass development induced by EAC cells. It exhibited significant anti-tumor activity in mice, when used at the dose of 100 mg/kg/day i.p., for 14days. The administration of Euphorbia hirta (100 mg/kg/day i.p.) resulted in an increase (P<0.001) of the life span (59.9%) of ascites tumor bearing mice as compared to the control group. After 14 days, on developed tumor masses, Euphorbia hirta administration brought about significant reduction in tumor volume and it reverse the changes in the hematological parameters, responding to tumor inoculation. The results are indicative of the anti-tumor activity of Euphorbia hirta against EAC induced tumor in a dose dependent manner.

• Archives of Pharmacal Research
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• 제12권4호
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• pp.233-235
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• 1989

Sodium salts of phosphated capric and myristic acyl derivatives of mannitol were prepared and evaluated for surface activity, foam characteristics and emulsifying properties. Triacyl mannitols of cappric and myristic acid have better emulsifying property than the corresponding di and monocompounds.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.110.2-110.2
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• 2002

• Natural Product Sciences
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• 제22권3호
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• pp.220-224
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• 2016

Anti-Helicobacter pylori activity guided fractionation led to the isolation of five anthraquinones, two stilbenes and one naphthoquinone from the EtOAc fraction of Polygonum cuspidatum, using silica gel column chromatography, Sephadex-LH20, MPLC and recrystallization. The chemical structures were identified to be physcion (1), emodin (2), anthraglycoside B (3), trans-resveratrol (4), anthraglycoside A (5), polydatin (6), 2-methoxy-6-acetyl-7-methyljuglone (7) and citreorosein (8) by UV, $^1H$-NMR, $^{13}C$-NMR and mass spectrometry. Anti-Helicobacter pylori activity including MIC values of each compound was evaluated. All of the isolates exhibited anti-H. pylori activity of which MIC values were lower than that of a positive control, quercetin. Compounds 2 and 7 showed potent growth inhibitory activity. Especially, a naphthoquinone, compound 7 displayed most potent antibacterial activity with $MIC_{50}$ value of $0.30{\mu}M$ and $MIC_{90}$ value of $0.39{\mu}M$. Although anti-H. pylori activity of this plant was previously reported, this is the first report on that of compounds isolated from this species. From these findings, P. cuspidatum roots or its isolates may be useful for H. pylori infection and further study is needed to elucidate mechanism of action.

• Archives of Pharmacal Research
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• 제27권9호
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• pp.885-892
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• 2004

Due to the rapidly growing number of resistant strains of bacteria, the search for antibacterial agents with new modes of action will always remain an important and challenging task. Thus, the reaction of 2-substituted or. unsubstituted-4-(4-acetylanilino)-5,6,7,8-terahydrobenzo［b］ thieno［2,3-d］pyrimidine derivatives 1-3 with the hydrazine derivatives, semi and / or thiosemi-carbazides, provided the corresponding hydrazones 4-6 and semi and/or thiosemicarbazones 7-9. Claisen-Schmidt condensation of compounds 1 or 2 with the appropriate aldehyde yielded the chalcones 10, 11 which, when treated with hydroxylamine hydrochloride gave rise to the isoxazoline-containing compounds 12, 13. Furthermore, reacting the respective chalcones 10, 11 with different hydrazines, urea and/or thiourea, furnished compounds 14, 15, 16, and 17 respectively. Representative compounds were tested for their antimicrobial activity against Candida Albicans and certain gram-positive and gram-negative bacteria. Their MICs were then determined. Compound 15e, showed a broad spectrum of activity while most of the other com-pounds showed varying antimicrobial activity.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.483-488
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• 2011

Present work comprises of synthesis various analogues of ciprofloxacin by introducing new functionality at carboxylic group position via ester aminolysis reaction. For this purpose the carboxylic group at C-3 was esterified and later subjected to nucleophilic attack at the carbonyl carbon by various aromatic amines. Structure of the analogues was confirmed by different techniques i.e. IR, $^1H$ NMR and mass spectrometry. The antibacterial activity of the derivatives was also assessed with the parent against a series of Gram-positive and Gram-negative bacteria. The synthesized compounds showed diverse antimicrobial profile among which most compounds possessed a comparable or better activity in comparison to the ciprofloxacin. Additionally unlike ciprofloxacin, some of the derivatives were also found to show antifungal activity.