Indole Alkaloids from Chaetomium globosum
Indole Alkaloids from Chaetomium globosum
复制标题
球毛壳菌中的吲哚生物碱
DOI：
10.1021/np5007235
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发表时间：
2015-07-01
影响因子：
5.1
通讯作者：
Li, Guo-You
中科院分区：
文献类型：
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作者：
Xu, Guo-Bo;He, Gu;Li, Guo-You
从球形毛壳菌（Chaetomium globosum）的水稻培养物中分离得到两个新的吲哚生物碱类化合物chaetocochin J（1）和chaetoglobinol A（8），沿着chetomin（2）、chetocludin A（3）、cochliodinol（9）和semicochliodinol（10）。通过波谱分析鉴定了它们的结构。通过UPLC和质谱分析的组合，鉴定了三个新的epipolithiodioxopiperazines，毛壳藻G-I（5-7）。毛壳菌I含有两个硫桥，一个由C-3和C-11 a之间的三个硫原子构成，另一个由C-3'和C-6'之间的四个硫原子构成。通过失去硫原子，毛壳素I容易转化为毛壳素（2）、毛壳素A（3）、毛壳素D（4）、毛壳素G（5）和毛壳素H（6）。化合物1-3和8对枯草芽孢杆菌表现出抗菌活性，MIC分别为25、0.78、0.78和50 μ g/mL，但对革兰氏阴性菌（大肠杆菌）没有抗菌活性。化合物2和8即使在200和100 μ g/mL的高浓度下也分别对白色念珠菌、禾谷镰刀菌、Fusarium vasinfectum、酿酒酵母和尼日尔无活性。化合物8显示出对1，1-二苯基-2-苦基-肼基（DPPH）和2，2 ′-连氮基-双-3-乙基苯并噻唑啉-6-磺酸自由基（ABTS（+中心点））的自由基清除能力，IC 50值分别为143.6和45.2 μ M。化合物1-3在试验浓度（89.9-108.3 μ M）下对DPPH和ABTS（+中心点）的自由基清除率小于20%。超氧阴离子自由基清除实验表明，化合物1-3和8对超氧阴离子自由基的清除能力分别为14.8%（90.9 μ M）、18.1%（90.9 μ M）、51.5%（88.3 μ M）和30.4%（61.3 μ M）。
Two new indole alkaloids chaetocochin J (1) and chaetoglobinol A (8), along with chetomin (2), chetoseminudin A (3), cochliodinol (9), and semicochliodinol (10), were isolated from the rice culture of the fungus Chaetomium globosum. Their structures were elucidated by spectral analysis. Three new epipolythiodioxopiperazines, chaetocochins G-I (5-7), were identified by the combination of UPLC and mass spectrometric analysis. Chaetocochin I contained two sulfur bridges, one formed by three sulfur atoms between C-3 and C-11a, and the other formed by four sulfur atoms between C-3' and C-6'. Chaetocochin I was readily transformed into chetomin (2), chetoseminudin A (3), chaetocochin D (4), chaetocochin G (5), and chaetocochin H (6) by losing sulfur atoms. Compounds 1-3, and 8 exhibited antibacterial activities against Bacillus subtilis with MICs of 25, 0.78, 0.78, and SO mu g/mL, respectively, but not against Gram-negative bacterium (Escherichia coli). Compounds 2 and 8 were inactive against Candida albicans, Fusarium graminearum, Fusarium vasinfectum, Saccharomyces cerevisiae, and Aspergillus niger even at the high concentrations of 200 and 100 mu g/mL, respectively. Compound 8 showed free radical scavenging capacity against the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical (ABTS(+center dot)), with IC50 values of 143.6 and 45.2 mu M, respectively. The free radical scavenging capacity rates of compounds 1-3 on the DPPH and ABTS(+center dot) were less than 20% at the test concentrations (89.9-108.3 mu M). The superoxide anion radical scavenging assay indicated that compounds 1-3, and 8 showed 14.8% (90.9 mu M), 18.1% (90.9 mu M), 51.5% (88.3 mu M), and 30.4% (61.3 mu M) superoxide anion radical scavenging capacity, respectively.