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101.
Withanolides, the secondary metabolite from Withania species is used in Ayurvedic medicine and now proved to have potential use in treating cardiovascular, Alzheimer’s disease, etc. Its production in plants varies between genotypes with very low yield. For improved industrial commercialisation, there is a need to increase its production. Endophytic fungi are symbiotically associated with plants and can synthesise the same bioactive compounds and natural products as their host plant. There are no reports available on withanolide-producing (endophytic) fungi. The present study identified an endophytic fungus (Taleromyces pinophilus) from leaves of Withania somnifera which produces withanolides in the medium. The structure of withanolide was confirmed by 1H NMR, LC-MS analyses and quantified by HPLC analysis. The fungus produces high amount of withanolide when compared to leaf and root of W. somnifera. The fungus can be exploited to produce the withanolide to meet its demand. 相似文献
102.
Two new γ-pyrones, xylaropyrones B (1) and C (2), together with three known compounds, xylaropyrone (3), annularin A (4) and annularin C (5), were isolated from solid cultures of the endophytic fungus Xylaria sp. SC1440. The structures of these compounds were determined mainly by analysis of their NMR spectroscopic data. The relative configurations of 1 and 2 were assigned on the basis of J-based configurational analysis, and the absolute configurations were established by experimental and TDDFT calculated ECD spectra. The isolated compounds were evaluated for cytotoxic and tyrosinase inhibitory activity. 相似文献
103.
Eight new tetramic acid derivatives, cladosporiumins A–H (1–8) were isolated from a culture broth of Cladosporium sp. SCSIO z0025 derived from the deep-sea sediment collected from Okinawa Trough. Their structures were elucidated by extensive spectroscopic data analysis. Compounds 1–3 were unique 3-acyltetramic acids with a hexyl enic alcohol side chain and a six-membered lactone ring substituted at C-3 of the 2, 4-pyrrolidinedione skeleton. The absolute configurations of chiral carbons of the 2, 4-pyrrolidinedione unit in 1–4 and 7 were established by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. And the absolute configurations of chiral carbons of the six-membered lactone ring in 1–3 were established by density functional theory calculation of their 13C NMR chemical shifts. In addition, all the compounds were tested for cytotoxic, antibacterial, anti-biofilm, and AchE inhibitory activities. 相似文献
104.
从红树林内源真菌2526#分离到Sterigmatocystin 总被引:4,自引:0,他引:4
从海洋资源中寻找药物已越来越受到重视 ,已有的研究表明海洋资源有可能成为治疗人类疑难病症和延年益寿药物的丰富源泉[1] 。本研究组在从海洋微生物筛选新药的过程中 ,已发现多种结构奇特而具有强生理活性的化合物[2~ 4 ] 。Sterigmatocystin最早分离自陆生真菌Aspergillusversicolor的代谢产物[5] ,随后人们对其结构、生源合成及药理活性进行了广泛的研究。结果表明 ,sterigmatocystin是细胞毒性更强的化合物AflatoxinB1的生源合成前体。本文报道从采自香港红树Avi… 相似文献
105.
Jonathan Sorres To Hebra Nicolas Elie Charlotte Leman-Loubire Tatyana Grayfer Philippe Grellier David Touboul Didier Stien Vronique Eparvier 《Molecules (Basel, Switzerland)》2022,27(4)
Social insects are in mutualism with microorganisms, contributing to their resistance against infectious diseases. The fungus Pseudallescheria boydii SNB-CN85 isolated from termites produces ovalicin derivatives resulting from the esterification of the less hindered site of the ovalicin epoxide by long-chain fatty acids. Their structures were elucidated using spectroscopic analysis and semisynthesis from ovalicin. For ovalicin, these compounds displayed antiprotozoal activities against Plasmodium falciparum and Trypanosoma brucei, with IC50 values of 19.8 and 1.1 µM, respectively, for the most active compound, i.e., ovalicin linoleate. In parallel, metabolomic profiling of a collection of P. boydii strains associated with termites made it possible to highlight this class of compounds together with tyroscherin derivatives in all strains. Finally, the complete genome of P. boydii strains was obtained by sequencing, and the cluster of potential ovalicin and ovalicin biosynthesis genes was annotated. Through these metabolomic and genomic analyses, a new ovalicin derivative named boyden C, in which the 6-membered ring of ovalicin was opened by oxidative cleavage, was isolated and structurally characterized. 相似文献
106.
Xylariphilone: a new azaphilone derivative from the seagrass-derived fungus Xylariales sp. PSU-ES163
Jiraporn Arunpanichlert Souwalak Phongpaichit Orathai Supaphon Jariya Sakayaroj 《Natural product research》2016,30(1):46-51
One new azaphilone derivative, named xylariphilone (1), along with 10 known compounds was isolated from the seagrass-derived fungus Xylariales sp. PSU-ES163. Their structures were elucidated on the basis of extensive spectroscopic analysis. The absolute and relative configurations of 1 were determined by circular dichroism spectroscopy and NOEDIFF data. The antimicrobial and cytotoxic activities of the isolated compounds were evaluated. 相似文献
107.
Hong Wei 《Tetrahedron》2005,61(33):8054-8058
Shimalactone A (1), a novel polyketide having bicyclo[4.2.0]octadiene and oxabicyclo[2.2.1]heptane units, was isolated from a cultured marine fungus of Emericella variecolor GF10. The stereo structure of 1 was deduced from 2D NMR and X-ray crystallographic analyses of 1 and its derivatives. The absolute structure of 1 was determined by application of the CD allylic benzoate rule to the benzoate derivative of 1. Shimalactone A (1) induced neuritogenesis at 10 μg/mL against neuroblastoma Neuro 2A cells. 相似文献
108.
Anton N. Yurchenko Olga F. Smetanina Elena V. Ivanets Trinh Thi Hoai Phan Ngoc Thi Duy Ngo Olesya I. Zhuravleva 《Natural product research》2020,34(18):2589-2594
AbstractTwo new auroglaucin-derived compounds, niveoglaucins A (1) and B (2), together with four known related compounds were isolated from extract of the marine sediment-derived strain of Aspergillus niveoglaucus. The structures of these compounds were determined by 1D and 2D NMR spectroscopy and high resolution MS. The plausible biosynthetic pathway was proposed for new compounds 1 and 2. The neuroprotective activity in 6-OHDA-induced Parkinson’s disease cell model was shown for niveoglaucin A (1). 相似文献
109.
Kongkiat Trisuwan Vatcharin Rukachaisirikul Kawitsara Borwornwiriyapan Souwalak Phongpaichit Jariya Sakayaroj 《Tetrahedron letters》2014
Two new benzopyranones, named coniochaetones E (1) and F (2), one new xanthone, penicillone C (3), and one new benzophenone, penicillanone (4), are isolated from the soil fungus Penicillium citrinum PSU-RSPG95, together with ten known compounds. Their structures are identified on the basis of spectroscopic data. The isolated compounds are evaluated for their cytotoxic activity. 相似文献
110.
Lena Hammerschmidt Abdessamad Debbab Tu Duong Ngoc Victor Wray Catalina Perèz Hemphil WenHan Lin Heike Broetz-Oesterhelt Matthias U. Kassack Peter Proksch Amal H. Aly 《Tetrahedron letters》2014
Five new polyketide derivatives, 6′-hydroxypestalotiopsone C (1), acropyrone (2), bicytosporone D (3), waol acid (4), and pestalotiopene C (5), together with seven known metabolites (6–12), were obtained from extracts of the endophytic fungus Acremonium strictum, isolated from the mangrove tree Rhizophora apiculata. The structures of the isolated compounds were elucidated on the basis of comprehensive NMR and MS analysis. Compounds 6, 7, and 9 showed moderate cytotoxic activity against human cisplatin-sensitive (IC50 values 27.1, 76.2, and 8.3 μM, respectively) and resistant A2780 cell lines (IC50 values 12.6, 30.1, and 19.0 μM, respectively), whereas only 9 exhibited antibacterial activity against Staphylococcus aureus (MIC value 14.3 μM). 相似文献