中文摘要：

目的对采自中国南海的紫柳珊瑚（Muriceopsis flavida）的生物活性成分进行研究。方法应用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、反相高效液相层析（RP-HPLC）等分离手段对紫柳珊瑚的乙醚提取物进行分离纯化,应用核磁共振（NMR）、质谱（MS）等波谱手段对得到的化合物进行结构鉴定,采用琼脂扩散试验法对分离得到的化合物进行体外抗微生物活性测试。结果从紫柳珊瑚乙醚提取物中分离得到5种过氧化甾醇,分别鉴定为：（22E,24S）-5α,8α-过氧化麦角甾-6,22-二烯-3β-醇（1）、（22E,24R）-5α,8α-过氧化麦角甾-6,22-二烯-3β-醇（2）、（24R）-5α,8α-过氧化胆甾-24-乙基-6-烯-3β-醇（3）、（22E）-5α,8α-过氧化胆甾-6,22-二烯-3β-醇（4）、5α,8α-过氧化胆甾-6-烯-3β-醇（5）。体外抗微生物活性测试表明这5种化合物均有不同程度的抗微生物活性。结论首次从中国南海紫柳珊瑚中得到5种过氧化甾醇,其中化合物2对微藻显示强烈的生长抑制活性,具有进一步研究的价值。

英文摘要：

Objective To investigate the bioactive chemical constituents of gorgonian Muriceopsis flavida collected from the South China Sea.Methods The Et_2O extract of the sample was purified by repeated column chromatographies on silica gel,Sephadex LH-20,and RP-HPLC.The structures of the obtained compounds were elucidated based on detailed spectroscopic analysis using mass spectrometry（MS） and nuclear magnetic resonance（NMR）.The in vitro antimicrobial activities of the identified compounds were assessed by an agar diffusion test.Results Five 5α,8α-epidioxy sterols were isolated from the Et_2O extract（1-5）,and their structures were determined as：（22E,24S）-5α,8α-epidioxy-24-methyl-cholesta-6,22-dien-3β-ol（1）,（22E,24R）-5α,8α-epidioxy-24-methyl-cholesta-6,22-dien-3β-ol（2）,（24R）-5α,8α-epidioxy-24-ethyl-cholesta-6-en-3β-ol（3）,（22E）-5α,8α-epidioxy-cholest-6,22-dien-3β-ol（4）,and 5α,8α-epidioxy-cholest-6-en-3β-ol（5）.These compounds showed different degrees of antimicrobial activities in bioassay in vitro.Conclusion The five compounds have been identified for the first time from the gorgonian Muriceopsis flavida.Compounds 2 shows a strong anti-algae effect and is worth further studying.