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31.
The marine fungus Chondrostereum sp. was collected from a soft coral Sarcophyton tortuosum from the South China Sea. This fungus was cultured in glucose-peptone-yeast (GPY) medium and the culture broth was extracted with EtOAc. By the method of 1H NMR pre-screening and tracing the diagnostic proton signals of the methyl groups, two new hirsutane-type sesquiterpenoids, chondrosterins N and O (1 and 2) were isolated from the metabolite extracts. Their structures were elucidated on the basis of MS, 1D and 2D NMR data. 相似文献
32.
The ethyl acetate extract of an ISP-2 agar cultivation of the wasp nest-associated fungus Penicillium sp. CMB-MD14 exhibited promising antibacterial activity against vancomycin-resistant enterococci (VRE), with a bioassay guided chemical investigation yielding the new meroterpene, oxandrastin A (1), the first andrastin-like metabolite with an extra oxygenation at C-2. A culture media optimisation strategy informed a scaled-up rice cultivation that yielded 1, together with three new oxandrastins B–D (2–4), two known andrastins C (5) and F (6), and a new meroterpene of the austalide family, isoaustalide F (7). Structures of 1–7 were assigned based on detailed spectroscopic analysis and chemical interconversion. A GNPS molecular networking analysis of the rice cultivation extract detected the known austalides B (8), H (9), and H acid (10), tentatively identified based on molecular formulae and co-clustering with 7. That the anti-VRE properties of the CMB-MD14 extract were exclusively attributed to 1 (IC50 6.0 µM, MIC99 13.9 µM), highlights the importance of the 2-OAc and 3-OAc moieties to the oxandrastin anti-VRE pharmacophore. 相似文献
33.
Five cassava flour wastewater (manipueira) preparations were tested as culture media for biosurfactant production by a wild-type Bacillus sp. isolate. No-solids (F), no-solids diluted (F/2), natural (I), natural diluted (I/2), and decanted (IPS) were the tested
manipueira media. The microorganism was able to grow and to produce biosurfactant on all manipueira preparations. The media whose solids were removed (F and F/2) showed better results than preparations with the presence of
solids (I, I/2, and IPS). No-solids medium (F) showed a surface tension of 26,59 mN/m and reciprocal of critical micelle concentration
of over 100 and was selected as a potential substrate for biosurfactant production. 相似文献
34.
One novel 7-membered lactone derivative, penicillilactone A (1), together with two known compounds, rugulosin A (2) and rugulosin (3) were isolated from the sponge-derived fungus Penicillium sp. LS54. Their structures were elucidated on the basis of spectroscopic analysis and comparison with literature data. Remarkably, penicillilactone A (1) is the first natural product containing a 7-membered lactone ring fused with a furan core. Penicillilactone A (1) exhibited moderate antibacterial activity against aquatic pathogen Vibrio harveyi with an MIC value of 8 μg/mL. 相似文献
35.
Iván Montenegro 《Natural product research》2019,33(8):1214-1217
A series of novel dihydrochalcone derivatives 2–7 were synthesized from dihydroisorcordoin 1 which was isolated from the aerial parts of Adesmia balsamica. The structures of all compounds were confirmed by 1H NMR, 13C NMR, and HRMS. Their anti-oomycete activity was evaluated in vitro against Saprolegnia parasitica and Saprolegnia diclina. Some of the newly synthesized compounds exhibited better anti-oomycete activities at low values compared with bronopol and fluconazole as positive controls. Among them, compound 7 exhibited strong activity, with minimum inhibitory concentration and minimum oomyceticidal concentration values of 75 and 100 μg/mL, respectively. 相似文献
36.
Kyosuke Morimoto Thien Phuc Le Sudipta Kumar Manna I. N. Chaithanya Kiran Shinji Tanaka Masato Kitamura 《化学:亚洲杂志》2019,14(19):3221-3221
37.
<正>A new naphthoquinone compound named 7-hydroxyl-8-methoxyltrypethelone 3 together with two known compounds trypethelone 1 and trypethelone methyl ether 2 was isolated from cultured mycobiont of Astrothelium sp.The structures were elucidated by 1D and 2D NMR spectroscopic analysis as well as comparison with those reported in literatures.Compound 1 displayed significant antibacterial activity against Bacillus subtilis(ATCC 6633),and showed modest antibacterial activity against Staphylococcus aureus col(MRSA)(CGMCC 1.2465),while compounds 2 and 3 showed modest antibacterial activity against Enterococcus faecalis 850E(CGMCC 1.2135) and S.aureus col(MRSA)(CGMCC 1.2465). 相似文献
38.
Chin-Soon Phan Takashi Kamada Takahiro Ishii Toshiyuki Hamada 《Natural product research》2019,33(6):808-813
One new compound, 12-epi-9-deacetoxyxenicin (1) along with a hydroperoxide product, 12-epi-9-deacetoxy-8-hydroperoxyxenicin (2) and two known sesquiterpenoids (3–4) were isolated from a population of Bornean soft coral Xenia sp. The structures of these secondary metabolites were elucidated based on their spectroscopic data. Compounds 1 and 2 showed cytotoxic activity against ATL cell line, S1T. In addition, compound 3 exhibited hyphal inhibition of Lagenidium thermophilum. 相似文献
39.
Dan Zheng Li Han Yi Jiang Yan‐Ru Cao Jiang Liu Xiu Chen Yi‐Qing Li Xue‐Shi Huang 《Magnetic resonance in chemistry : MRC》2013,51(3):188-191
Four new prenylindole derivatives, (R)‐6‐(2,3‐dihydroxy‐3‐methylbutyl)indole (1), (R)‐6‐(2,3‐dihydroxy‐3‐methylbutyl)indolin‐2‐one (2), and an unseparated mixture of (Z)‐6‐(4‐hydroxy‐3‐methylbut‐2‐en‐1‐yl)indolin‐2‐one (3a) and (E)‐6‐(4‐hydroxy‐3‐methylbut‐2‐en‐1‐yl)indolin‐2‐one (3b) with a ratio of 3 : 2, were isolated from the culture broth of a streptomycete isolated from Ailuropoda melanoleuca feces. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopic techniques. The absolute configuration of 1 was determined by Mosher's method. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
40.
Dr. Nicole M. G. Franssen Dr. Bernd Ensing Maruti Hegde Prof. Dr. Theo J. Dingemans Ben Norder Prof. Dr. Stephen J. Picken Gert O. R. Alberda van Ekenstein Dr. Ernst R. H. van Eck Dr. Johannes A. A. W. Elemans Mark Vis Prof. Dr. Joost N. H. Reek Prof. Dr. Bas de Bruin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(35):11457-11457