Secondary Metabolites of the Endophytic Fungus Lachnum abnorme from Ardisia cornudentata

Fractionation of an EtOAc-soluble fraction of the solid fermentate of an endophytic fungus, Lachnum abnorme Mont. BCRC 09F0006, derived from the endemic plant, Ardisia cornudentata Mez. (Myrsinaceae), resulted in the isolation of three new chromones, lachnochromonins D–F (1–3), one novel compound, lachabnormic acid (4), along with nine known compounds (5–13). Their structures were elucidated by spectroscopic analyses. Alternariol-3,9-dimethyl ether (6) was given the correct data as well as 2D spectral analyses for the first time. This is the first report of the isolation of one unprecedented compound 4 from Lachnum genus, while all known compounds were also found for the first time from Lachnum. The effects of some isolates (3, 4, 7–9, 10, and 13) on the inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 murine macrophages were also evaluated. Several compounds exhibited weak inhibitory activity on lipopolysaccharide (LPS)-stimulated NO production in RAW 264.7 macrophages.     

虎舌红生物碱类成分的提取分离与结构鉴定

采用生物碱系统提取、硅胶柱层析分离,V(苯)∶V(乙酸乙酯)∶V(二乙胺)=7∶2∶1及V(氯仿)∶V(乙酸乙酯)∶V(二乙胺)=8∶1∶1溶剂系统梯度洗脱,从虎舌红中分离出2种淡黄色油状生物碱SW-Ⅰ及SW-Ⅱ,前者经元素分析、红外光谱(IR)、紫外光谱(UV)及核磁共振氢谱(1HNMR)鉴定,其化学结构为去氢飞廉碱(C16H22N4O2)。     

红外光谱法测定虎舌红提取物中的总黄酮

采用索氏回流法及溶剂萃取法成功地提取了虎舌红中的总黄酮,并对其结构进行了鉴定,采用红外光谱法对提取物中总黄酮的含量进行了测定.结果表明,虎舌红提取物中总黄酮含量为19.47 mg·g-1,与紫外可见分光光度法测定结果基本一致;相对标准偏差(RSD)为2.09％(n=6),加标回收率为93.54％～104.35％,平均回...     

虎舌红多糖超声波辅助提取工艺优化及其抗氧化活性评价

以虎舌红为原料,蒸馏水为提取剂,对超声波辅助提取虎舌红多糖的工艺进行优化,并对虎舌红多糖的抗氧化性进行评价。结果表明:虎舌红多糖最佳提取工艺为提取温度65℃,提取时间20 min,料液比115(g/mL),提取次数4次,该条件下虎舌红多糖得率为(3.42±0.28)mg/g。虎舌红多糖有较好的抗氧化活性,当多糖浓度达到4mg/mL时,对DPPH清除率强于相同浓度BHT;0.5%多糖对猪油抗氧化效果与相同浓度BHT相当。     

超临界萃取气-质联用分析虎舌红挥发油化学成分

用超临界流体萃取法对虎舌红挥发油的化学成分进行了分离提取研究,用气相-质谱联机技术,对其中的46种组分进行了鉴定,并测定了相对含量。结果表明,所鉴定出的46个组分中,质量分数在1.0%以上的组分有:石竹烯17.20%、α-石竹烯9.02%、3,7,11-三甲基-1,6,10-十二碳三烯-3-醇7.03%、兰桉醇5.54%、龙脑5.51%、α-萜品醇5.02%、水杨酸甲酯2.23%、芳樟醇2.10%、苯乙醇2.19%、α-杜松醇4.45%、己酸4.55%、α-没药醇2.51%、丁子香基乙醇2.11%、金合欢醇1.78%、β-没药烯1.71%、3-己烯-1-醇1.67%、氧化石竹烯1.62%等,它们占挥发油总质量的87.24%。     

双水相体系萃取虎舌红皂苷及稳定性研究

目的 选用聚乙二醇（PEG）-硫酸铵（(NH4)2SO4）双水相体系萃取虎舌红皂苷,并研究皂苷的稳定性。方法 以萃取率为指标,考察水浴时间、水浴温度、PEG平均分子量、PEG质量分数、(NH4)2SO4质量分数、体系pH值对萃取效果的影响,采用响应曲面法对萃取条件进行优化,并对虎舌红皂苷进行稳定性研究。结果 得到了最佳萃取条件,水浴时间为40 min,水浴温度为70 ℃,PEG600质量分数为25.0%,(NH4)2SO4质量分数为21.0%,pH值为6.20,此时虎舌红皂苷的萃取率为4.73%。研究表明,虎舌红皂苷适于保存在20 ℃以下、pH为6的低温微酸性环境中。结论 此体系的建立能有效萃取虎舌红皂苷,为其后续研究提供参考依据。