唐古特瑞香的化学成分研究

从唐古特瑞香(Daphne tangutica Maxim)95%乙醇提取物石油醚部分分离得到14个化合物,通过波谱学方法鉴定为β-谷甾醇(1)、β-胡萝卜苷(2)、2,4-二羟基-3,6-二甲基苯甲酸甲酯(3)、蛇床子素(4)、植物醇(5)、软脂酸(6)、stigmast-5-ene-3β,7α-diol(7)、(-)-lariciresinol(8)、daphnetin(9)、daphnoretin(10)、(-)-丁香树脂醇(11)、( )-medioresinol(12)、daphnelicin(13)和咖啡酸二十二酯(14)。     

Evaluation of Daphne genkwa diterpenes: fingerprint and quantitative analysis by high performance liquid chromatography

Daphne genkwa contains a novel class of anticancer diterpene esters that inhibit DNA topoisomerase I. Fingerprint and quantitative analysis by HPLC were performed in order to characterise and evaluate D. genkwa. A standard fingerprint of Daphne diterpene esters from the root extract was first established by HPLC-UV, and the major peaks in the fingerprint profile were preliminarily determined using HPLC-MS. The principal Daphne diterpene esters, yuanhuacine (1), yuanhuadine (2), yuanhuajine (3) and yuanhuagine (4), were isolated and identified using a combination of UV, IR, MS, 1H-NMR and 13C-NMR spectral data. Quantitative analysis indicated that 1 was the principal component in the root, and that 2 was the major component in the buds. The average extraction rates of 1 and 2 were 0.0151 and 0.0033% (n=10) from the root, respectively, and 0.0020 and 0.0078% (n=3) from the buds, respectively.     

Daphne odora Exerts Depigmenting Effects via Inhibiting CREB/MITF and Activating AKT/ERK-Signaling Pathways

Daphne odora, a blooming shrub, has been traditionally used for various medicinal purposes. However, information on its anti-melanogenic activity and dermal application is limited. In this study, the Daphne odora extract (DOE), with constituents including daphnetin, was used to investigate depigmenting activity and the underlying mechanism of Daphne odora. DOE inhibited in vitro and cellular tyrosinase activity in a dose-dependent manner, and reduced the α-MSH-induced melanin biosynthesis to a control level. The protein expressions of melanin synthesis-related enzymes were also significantly reduced by DOE. Moreover, DOE decreased the phosphorylation of cAMP-response element binding proteins (CREBs) induced by α-MSH in B16F10 cells, while it activated phosphorylated extra-cellular signal-regulated kinases (ERKs) and protein kinase B (AKT) expression. These results suggest that DOE might inhibit the melanogenesis signaling pathways by activating ERK- and AKT-signaling pathways to regulate the expression of CREB and MITF and its downstream pathways. Therefore, DOE could potentially be developed as a depigmenting agent.     

Novel urease inhibitors from Daphne oleoids

Phytochemical investigations on the chloroform and ethyl acetate soluble fractions of the roots of the Daphne oleoids led to the isolation of the coumarin glycosides 1–6. Compound 5 with IC₅₀ values 22.05 and 26.30 μM repectively, was found to be the most active of these compounds when screened against Bacillus pasteurii and jack bean urease enzymes in a concentration-dependent fashion.     

芫花的花粉形态观察及生活力和萌发率分析

Pollen morphology of Daphne genkwa Sieb.et Zucc.was observed by scanning electron microscope(SEM),and its viability and germination rate were measured by TTC and sucrose in vitro culture methods.The results show that pollen is stenopalynous type with a diameter of 15.6-21.6 μm.Per pollen has 10-16 apertures which is irregular circular with a diameter of 1.4-2.0 μm.Surface ornamentation of pollen is rough reticulate pattern which is circular polygon(tetragon-heptagon,mostly pentagon-hexagon).Pollen viability is 51% by TTC.Sucrose of different concentrations has a significant effect on pollen germination rate during pollen culture.And pollen germination rate is the highest with a percentage of 27.0% in medium containing 50 g·L-1 sucrose,while pollen could not germinate in medium containing sucrose over 250 g·L-1.Otherwise,there is the phenomenon of "multi-aperture germination" during pollen germinating.     

Chemical constituents from the stem and root bark of Daphne giraldii Nitsche (Thymelaeaceae)

Eighteen compounds were isolated from the stem and root bark of Daphne giraldii Nitsche, including three categories: flavans (1–6), diphenylpropanes (7–12), and lignans (13–18). This is the first report on the occurrence of compounds 9, 11, 13–15, and 17–18 in D. giraldii. These compounds were elucidated using spectroscopic methods and by comparing their data to those reported in the literature. On the basis of our previous chemical research, the chemotaxonomic significance of the isolated compounds was discussed to a greater degree.     

New Coumarinyl Ethers in Daphne oleoides Schreb. Collected from Sardinia Island

The phytochemical analysis of the ethanolic extract obtained from D. oleoides collected from Sardinia Island allowed the isolation of several new constituents for the species ( 3 , 8 , and 9 ) together with two new coumarinyl ethers ( 1 and 2 ) besides the chemotaxonomic markers of the Daphne genus ( 4 – 7 and 10 ) which are also known to possess interesting biological activities. The structure of the new compounds were elucidated by extensive spectroscopic and spectrometric analyses. The identification of these compounds gives an experimental evidence of the variability in the secondary metabolites pattern owned by populations growing in restricted area in respect to populations not confined by geographical barrier.     

Daphne thanguensis sp. nov. (Thymelaeaceae) from Sikkim Himalaya

Daphne thanguensis sp. nov. from north Sikkim of eastern Himalaya is described and illustrated. It is a narrow endemic related to D. tangutica Maxim. Daphne thanguensis grows in open alpine pastures and differs from D. tangutica by having leaves with revolute margin and a tuft of hairs at apex, ebracteate inflorescence and flowers, calyx lobes with a tuft of hairs at apex and annular, slightly undulate hypogynal disk. The new taxon is also close to D. retusa Hemsl. But can easily be differentiated by its sessile inflorescence, ebracteate flowers and tuft of hairs at leaf apices and calyx lobe apices. A conservation status of the new species in accordance with the IUCN red list categories and criteria is provided and discussed.     

Ecological context of breeding system variation: sex, size and pollination in a (predominantly) gynodioecious shrub

BACKGROUND AND AIMS: Species that exhibit among-population variation in breeding system are particularly suitable to study the importance of the ecological context for the stability and evolution of gender polymorphism. Geographical variation in breeding system and sex ratio of Daphne laureola (Thymelaeaceae) was examined and their association with environmental conditions, plant and floral display sizes, and pollination environment in a broad geographic scale was analysed. METHODS: The proportion of female and hermaphrodite individuals in 38 populations within the Iberian Peninsula was scored. Average local temperature and precipitation from these sites were obtained from interpolation models based on 30 years of data. Pollination success was estimated as stigmatic pollen loads, pollen tubes per ovule and the proportion of unfertilized flowers per individual in a sub-set of hermaphroditic and gynodioecious populations. KEY RESULTS: Daphne laureola is predominantly gynodioecious, but hermaphroditic populations were found in northeastern and southwestern regions, characterized by higher temperatures and lower annual precipitation. In the gynodioecious populations, female plants were larger and bore more flowers than hermaphrodites. However, due to their lower pollination success, females did not consistently produce more seeds than hermaphrodites, which tends to negate a seed production advantage in D. laureola females. In the northeastern hermaphroditic populations, plants were smaller and produced 9-13 times fewer flowers than in the other Iberian regions, and thus presumably had a lower level of geitonogamous self-fertilization. However, in a few southern populations hermaphroditism was not associated with small plant size and low flower production. CONCLUSIONS: The findings highlight that different mechanisms, including abiotic conditions and pollinator service, may account for breeding system variation within a species' distribution range and also suggest that geitonogamy may affect plant breeding system evolution.