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排序方式: 共有146条查询结果,搜索用时 31 毫秒
71.
Further chemical study of secondary metabolites from the soil actinomycete Streptomyces sp. WS-13394 resulted in the isolation of four new alkylated anthraquinone analogues (5–8). Their structures were elucidated on the basis of extensive spectroscopic analysis, including HR-ESI-MS, 1D and 2D NMR. The new compounds, together with analogues obtained before (1–4), were tested for their in vitro cytotoxicity against Huh-7 and SGC-7901. 相似文献
72.
Four new bisamides 1–4, and two new rhamnosides (5, 6), along with four known compounds 7–10, were isolated from a scale culture of the mangrove-derived actinomycete Streptomyces sp. SZ-A15. All structures were determined through analysis of the UV, IR, HRESIMS, 1D and 2D NMR spectra as well as by comparison with literature data. BRD4 inhibition of all isolated compounds was evaluated. As for the ability to inhibit protein BRD4, compound 9 exhibited moderate activity with the value of 78.4 ± 2.2% at 10 μM. 相似文献
73.
Hao Zhou Ya-Bin Yang Rong-Ting Duan Xue-Qiong Yang Ju-Cheng Zhang Xiao-Guang Xie Li-Xing Zhao Zhong-Tao Ding 《中国化学快报》2016,27(7):1044-1047
Neopeapyran (1), an unusual furo[2,3b]pyran analogue, together with a new cyclopeptide, turnagainolide C (2), were isolated from Streptomyces sp. S2236 associated with the rhizosphere soil of Panax notoginseng. The planar structure and relative configuration of neopeapyran (1)) were elucidated on the basis of spectroscopic techniques, while the absolute configuration was determined by TDDFT calculation. The absolute configuration of turnagainolide C (2) was determined by partial hydrolysis, together with the advanced Marfey's method and spectroscopic analysis. The antimicrobial activities of these two compounds were also investigated. 相似文献
74.
Physico-chemical characteristics of vernamycin-A antibiotic biosynthesis by streptomyces SP-AZ-SH-29
Houssam M. Atta Bakry M. Haroun Mohamed A. Khalifa 《Journal of Saudi Chemical Society》2011,15(3):247-255
Seventy-five actinomycete isolates were isolated from different soil samples collected from different localities in Egypt. One of the actinomycete culture AZ-SH-29 from three cultures was found to produce a wide spectrum antimicrobial agent. The actinomycete isolate AZ-SH-29 matches with Streptomyces ramulosus in the morphological, physiological, and biochemical characters. Thus, it was given the suggested name Streptomyces ramulosus-AZ-SH-29. The parameters controlling the biosynthetic process of the antimicrobial agent formation including; different pH values, different temperatures, different incubation period, and different carbon and nitrogen sources, were fully investigated. The active metabolite was extracted using ethyl acetate (1:1, v/v) at pH 7.0. The separation of the active ingredient and its purification were performed using column chromatography (CC) technique. The physico-chemical characteristics of the purified antimicrobial agent have been investigated. This analysis indicates a suggested imperical formula of C20H25N2O5. The minimum inhibition concentrations “MICs” of the purified antibiotic and antiviral test were also determined. The purified antimicrobial agent was suggestive of being belonging to Depsipeptide (Mikamycin) group (Vernamycin-A antibiotic) produced by Streptomyces ramulosus, AZ-SH-29. 相似文献
75.
Xiao‐Li Huang Yao Gao Duo‐Qing Xue Hai‐Li Liu Chong‐Sheng Peng Feng‐Li Zhang Zhi‐Yong Li Yue‐Wei Guo 《Helvetica chimica acta》2011,94(10):1838-1842
A new indole alkaloid, streptomycindole ( 1 ), and a known related compound, N‐phenylacetyl‐L ‐tryptophan ( 2 ), have been isolated from Streptomyces sp. DA22, associated with South China Sea sponge Craniella australiensis. Their structures were established on the basis of a combination of mass spectrometry, 1H‐ and 13C‐NMR spectroscopic analyses, and chemical methods. 相似文献
76.
《Analytical letters》2012,45(8):1445-1452
Abstract A mediated enyme electrode was developed for the determination of L-glutamate, based on the immobilization of L-glutamate oxidase from Streptomyces sp. X 119–6. A graphite working electrode was used with 1,1 dimethylferrocene (DMF) as electron mediator. The electrode responded linearly to L-glutamate over the range 0.2 to 2 mM (0.029–0.29 g/l). The enzyme electrode was applied to the measurement of L-glutamate in various foodstuffs. 相似文献
77.
Kien Xuan Ngo Hiroshi Umakoshi Toshinori Shimanouchi Ryoichi Kuboi 《Colloids and surfaces. B, Biointerfaces》2009,73(2):399-407
The interaction between the neutral 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) liposomes and cell membrane of Streptomyces griseus induced by the heat treatment at specific temperature was investigated, focusing on the internalization of the neutral POPC liposomes with S. griseus cells. In an attempt to clarify the modes of liposome internalization, various kinds of inhibitors of endocytotic pathways were used to treat S. griseus cells. The efficiency of the heat treatment on liposome–cell membrane interactions was finally characterized based on the hydrophobic, electrostatic interactions and hydration effect. In fact, the internalization of the neutral liposomes into these cells was found to show higher rate and greater amount at higher temperatures. The kinetic study showed that the maximum amount of the internalized liposomes was, respectively, 469 × 105 and 643 × 105 liposomes/cell at 37 and 41 °C. The internalization of the neutral liposomes induced by the heat treatment was characterized, implying that the endocytosis occurred. The interactions involving the internalization, adsorption, and fusion of these liposomes with S. griseus cells were mainly contributed by the hydrophobic interaction and the unstable hydrogen bonds caused by the loss of water of surface hydration of cell membrane rather than the electrostatic interaction under the specific heat condition. 相似文献
78.
<正>Azalomycin F_(4a) 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The compound showed broad-spectrum antifungal activity and moderate cytotoxicity against human colon tumor cell HCT-116. 相似文献
79.
Ahmed S. Abu Zaid Ahmed E. Aleissawy Ibrahim S. Yahia Mahmoud A. Yassien Nadia A. Hassouna Khaled M. Aboshanab 《Molecules (Basel, Switzerland)》2021,26(13)
Background: This study aimed to produce, purify, structurally elucidate, and explore the biological activities of metabolites produced by Streptomyces (S.) griseus isolate , a recovered soil bacterium previously screened in our lab that showed promising cytotoxic activities against various cancer cell lines. Methods: Production of cytotoxic metabolites from S. griseus isolate KJ623766 was carried out in a 14L laboratory fermenter under specified optimum conditions. Using a 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium-bromide assay, the cytotoxic activity of the ethyl acetate extract against Caco2 and Hela cancer cell lines was determined. Bioassay-guided fractionation of the ethyl acetate extract using different chromatographic techniques was used for cytotoxic metabolite purification. Chemical structures of the purified metabolites were identified using mass, 1D, and 2D NMR spectroscopic analysis. Results: Bioassay-guided fractionation of the ethyl acetate extract led to the purification of two cytotoxic metabolites, R1 and R2, of reproducible amounts of 5 and 1.5 mg/L, respectively. The structures of R1 and R2 metabolites were identified as β- and γ-rhodomycinone with CD50 of 6.3, 9.45, 64.8 and 9.11, 9.35, 67.3 µg/mL against Caco2, Hela and Vero cell lines, respectively. Values were comparable to those of the positive control doxorubicin. Conclusions: This is the first report about the production of β- and γ-rhodomycinone, two important scaffolds for synthesis of anticancer drugs, from S. griseus. KJ623766相似文献
80.
María Inés Lapaz Andrés López José Carlos Huguet-Tapia Martín Fabián Pérez-Baldassari Cesar Iglesias Rosemary Loria 《Natural product research》2019,33(20):2951-2957
Two Streptomyces spp. strains responsible for potato common scab infections in Uruguay which do not produce diketopiperazines were identified through whole-genome sequencing, and the virulence factor produced by one of them was isolated and characterized. Phylogenetic analysis showed that both pathogenic strains can be identified as S. niveiscabiei, and the structure of the phytotoxin was elucidated as that of the polyketide desmethylmensacarcin using MS and NMR methods. The metabolite is produced in yields of ~200?mg/L of culture media, induces deep necrotic lesions on potato tubers, stuns root and shoot growth in radish seedlings, and is comparatively more aggressive than thaxtomin A. This is the first time that desmethylmensacarcin, a member of a class of compounds known for their antitumor and antibiotic activity, is associated with phytotoxicity. More importantly, it represents the discovery of a new virulence factor related to potato common scab, an economically-important disease affecting potato production worldwide. 相似文献