辣椒倍半萜环化酶基因在几种非生物诱发因子作用下的表达

报道了在CuCl2,HgCl2及NaCl、紫外线等几种诱发因子作用下辣椒倍半萜环化酶活性表达，并利用从辣椒中克隆出来的2个倍半萜环化酶等位基因cDNA的特异性片段，研究这两个等位基因在上述诱发因子作用下的表达情况，结果表明：在CuCl2,HgCl2,NaCl2、紫外线诱发作用下，离体辣椒叶片均能表现一定的倍半萜环化酶活性，而CK中几乎检测不出倍半萜环化酶活性，Northern Blot分析表明，辣椒倍半萜环化酶基因在逆境下被诱转导，两个cDNA在不同的诱发因子在相同的逆境胁迫下的表达有一定的特异性，推测该基因家族的不同成员在辣椒适应不同逆境的防御反应中有一定的意义，图5参6。     

苔藓Lophozia ventricosa挥发油化学成分研究

采用水蒸气蒸馏法提取苔藓Lophozia ventricosa挥发油，用毛细管色谱法对挥发油进行了分析，采用归-化法确定各组分的相对含量，并用GC—MS联用技术对分离的化学成分进行鉴定．经计算机检索并结合文献调研，共鉴定出28个化合物，占挥发油总量的93．3％，其中含1个单萜、23个倍半萜（15个为含氧倍半萜）和1个二萜，主要成分为Maalioxide（45．6％）和Eudesma-4．（15），7（11）-dien-8-one（28．9％）．图2表1参12     

三花紫菊的化学成分

从三花紫菊(NotoseristrifloraShih)(3)全草的甲醇提取物中分离鉴定出17个化合物,其中14个为倍半萜内酯dihydrosantamarine(1),sonchusideA(2),annuolidesD(3),ixerisosideD(4),11β,13-dihydro-hyporadiolide-8-0-(2-methylacrylate)(5),hyporadio1ide-8-0-(2-methylacrylate)(6),hypochoerolideG(7),hypochoerolideE(8),11β,13-di-hydrolactucin(9),cichoriosideB(10),jacquilenin(11),austricin(12),crepidiasideA(13)和crepidiasideB(14),另外3个化合物分别鉴定为3,5-二甲氧基-4-羟基苯甲醛(15),β-谷甾醇(16)和胡萝卜苷(17).上述化合物均为首次从该植物中分离得到.图1表1参14     

In vivo assessment of plant extracts for control of plant diseases: A sesquiterpene ketolactone isolated from Curcuma zedoaria suppresses wheat leaf rust

As an alternative to synthetic pesticides, natural materials such as plant extracts and microbes have been considered to control plant diseases. In this study, methanol extracts of 120 plants were explored for in vivo antifungal activity against Rhizoctonia solani, Botrytis cinerea, Phytophthora infestans, Puccinia triticina, and Blumeria graminis f. sp. hordei. Of the 120 plant extracts, eight plant extracts exhibited a disease control efficacy of more than 90% against at least one of five plant diseases. In particular, a methanol extract of Curcuma zedoaria rhizomes exhibited strong activity against wheat leaf rust caused by P. triticina. When the C. zedoaria methanol extracts were partitioned with various solvents, the layers of n-hexane, methylene chloride, and ethyl acetate showed disease control values of 100, 80, and 43%, respectively, against wheat leaf rust. From the C. zedoaria rhizome extracts, an antifungal substance was isolated and identified as a sesquiterpene ketolactone based on the mass and nuclear magnetic resonance spectral data. The active compound controlled the development of rice sheath blight, wheat leaf rust, and tomato late blight. Considering the in vivo antifungal activities of the sesquiterpene ketolactone and the C. zedoaria extracts, these results suggest that C. zedoaria can be used as a potent fungicide in organic agriculture.     

雷公藤新的降倍半萜成分

从贵州产雷公藤（ＴｒｉｐｔｅｒｙｇｉｕｍｗｉｌｆｏｒｄｉＨｏｋＦ．）中分离得到８个化合物,其中一个为新的降倍半萜化合物雷公藤酮（１）,根据光谱（ＩＲ,１ＨＮＭＲ,１３ＣＮＭＲ,ＨＲＭＳ,ＣＤ等）数据分析并通过Ｘ射线晶体分析确定了结构;另外７个化合物分别鉴定为雷公藤素（２）,（±）６氧２（４′羟基３′,５′二甲氧苯基）３,７二氧杂二环［３．３．０］辛烷（３）,ｔｒｉｐｔｅｒｉｆｏｒｄｉｎ（４）,雷公藤内酯酮（５）,雷公藤内酯醇（６）,雷公藤内酯甲（７）和对乙氧基乙酰替苯胺（８）．其中,３和８均为首次从该植物中分离得到．用二维核磁共振谱对３的氢谱和碳谱进行了指定