单条草的皂甙成分

从单条草（ＬｙｓｉｍａｃｈｉａｃａｎｄｉｄａＬｉｎｄｌ）全草中分离出３个皂甙类化合物,经波谱分析并结合化学方法鉴定为：报春花素Ａ３ＯβＤ吡喃木糖基（１→２）βＤ吡喃葡萄糖基（１→４）［βＤ吡喃葡萄糖基（１→２）］αＬ吡喃阿拉伯糖甙（１）、原报春花素Ａ３ＯβＤ吡喃木糖基（１→２）βＤ吡喃葡萄糖基（１→４）［βＤ吡喃葡萄糖基（１→２）］αＬ吡喃阿拉伯糖甙（ｌｙｓｉｋｏｉａｎｏｓｉｄｅ,２）和α菠甾醇葡萄糖甙（３）。其中１是新化合物,命名为单条草甙（ｃａｎｄｉｄｏｓｉｄｅ）。     

珍珠菜属八种植物的花粉形态研究

利用扫描电子显微镜,首次对珍珠菜属(LysimachiaL.)8种植物的花粉形态进行了观察研究,报道了花粉形态特征,探讨了花粉形态特征在分类学上的意义。结果表明:该属花粉粒大小和外壁雕纹可作为分种的依据。     

Saponins from Lysimachia candida

Three saponins were isolated from Lysimachia candida Lindl. By spectral and chemical analysis, they were identified as primulagenin A-3-O-β-D-xylopyranosy( 1→2)-β-D-glucopyranosyl( 1→4)-[β-D-glu- copyranosyl(1→2) ] -a-L-arabinopyranoside ( 1 ), protoprimulagenin A-3-O-β-D-xylopyranosyl( 1→2)-β-D-glu- copyranosyl( 1→4)-[ β-D-glucopyranosyl ( 1 →2) ]-a-L-arabinopyranoside ( lysikoianoside, 2) and a-spinas- teml-glucopyranoside (3) respectively. 1 is a new compound named candidoside.     

Batesian mimicry in the nonrewarding saprophytic orchid Danxiaorchis yangii

Batesian mimicry, a type of deceptive pollination, is a complicated strategy used by nonrewarding plants to attract pollinators, but some hypotheses concerning this have not been systematically verified. In order to show in detail a case of Batesian mimicry on saprophytic orchid Danxiaorchis yangii, the ecological relationship between Danxiaorchis yangii, Lysimachia alfredi and Dufourea spp. was explored. Lysimachia alfredi could provide a reward to Dufourea sp., whereas Danxiaorchis yangii not. The floral morphology and geographical distribution of these two plants were highly overlapping, and the fruit set rate of Danxiaorchis yangii was significantly positively correlated with the number of nearby L. alfredi individuals. In a glass cylinder experiment, Danxiaorchis yangii and L. alfredi attracted Dufourea spp. through visual signals, but the insect could not distinguish between flowers of the two plants before landing on flowers. The ultraviolet reflection spectra of flowers between the two plant species were highly similar. In the hexagonal color models constructed according to the visual characteristics of bees, the flower color signals of these two plant species highly overlap, indicating that the visual signals of the flowers of the two plants to the pollinator were greatly similar. All of these results provided evidence that Danxiaorchis yangii simulated the visual signals of L. alfredi through Batesian mimicry, thereby deceptively attracting Dufourea spp.     

New Cytotoxic Saponins from Lysimachia davurica Ledeb.

To investigate the saponins from whole plants of Lysimachia davurica Ledeb., two new saponins named davuricoside I （compound 1） and E （compound 2） were isolated. Their chemical structures were elucidated as 3β, 16α, 28, 29-tetrihydroxy-olean-12-en-3-O-β-D-glucopyranosyl-（1→2）-β-D-glucuronopyranoside （compound 1） and 3β, 16α, 29-trihydroxy-13, 28-epoxy-oleanane-3-O-β-D-glucopyranosyl-（1→2）-β-D-glucuronopyranoside （compound 2） on the basis of their one- and two-dimensional nuclear magnetic resonance and mass spectrometry data, and chemical methods. Compound 1 showed significant cytotoxic activity against human A2780 cells.