Wellsow Julia, Grayer Renée J, Veitch Nigel C, Kokubun Tetsuo, Lelli Roberto, Kite Geoffrey C, Simmonds Monique S J
Royal Botanic Gardens, Biological Interactions, Kew, Richmond, Surrey TW9 3AB, UK.
Phytochemistry. 2006 Aug;67(16):1818-25. doi: 10.1016/j.phytochem.2006.02.018. Epub 2006 Apr 24.
Bio-assay guided fractionation of an acetone extract of leaf material from Plectranthus saccatus Benth. resulted in the isolation of a beyerane diterpenoid. This compound, characterised by spectroscopic methods as ent-3beta-(3-methyl-2-butenoyl)oxy-15-beyeren-19-oic acid, showed insect antifeedant activity against Spodoptera littoralis. Known quinonoid abietane diterpenoids obtained from new sources included a mixture of the (4R,19R) and (4R,19S) diastereoisomers of coleon A from P. aff. puberulentus J.K. Morton, coleon A lactone from P. puberulentus J.K. Morton, and coleon U and coleon U quinone from P. forsteri 'Marginatus' Benth. These compounds, and the crude acetone extracts from the leaf surfaces of 11 species of Plectranthus, were tested for antifeedant activity against S. littoralis, antibacterial activity against Bacillus subtilis and Pseudomonas syringae and antifungal activity against Cladosporium herbarum. The coleon A mixture showed potent antifeedant activity against S. littoralis, whereas coleon U showed the greatest antimicrobial activity.
对皱叶香茶菜（Plectranthus saccatus Benth.）叶片材料的丙酮提取物进行生物测定导向的分级分离，得到了一种贝壳杉烷二萜。该化合物经光谱方法表征为对映-3β-(3-甲基-2-丁烯酰氧基)-15-贝壳杉-19-酸，对斜纹夜蛾（Spodoptera littoralis）表现出拒食活性。从新来源获得的已知醌类枞酸型二萜包括来自柔毛香茶菜近缘种（P. aff. puberulentus J.K. Morton）的A组分（coleon A）的(4R,19R)和(4R,19S)非对映异构体混合物、来自柔毛香茶菜（P. puberulentus J.K. Morton）的A组分内酯、以及来自‘Marginatus’香茶菜（P. forsteri 'Marginatus' Benth.）的U组分（coleon U）和U组分醌。对这些化合物以及11种香茶菜叶片表面的粗丙酮提取物进行了测试，检测其对斜纹夜蛾的拒食活性、对枯草芽孢杆菌（Bacillus subtilis）和丁香假单胞菌（Pseudomonas syringae）的抗菌活性以及对草本枝孢菌（Cladosporium herbarum）的抗真菌活性。A组分混合物对斜纹夜蛾表现出强效拒食活性，而U组分表现出最大的抗菌活性。
