Flavone 5-O-glucosides from Daphne sericea

The aerial parts of Daphne sericea yielded two new flavonoids, luteolin 7-methyl ether 5-β-d-glucoside and luteolin 7,3′-dimethyl ether 5-β-d-glucoside, as well as luteolin 7-methyl ether, isovitexin, apigenin and its 7-β-d-glucoside.     

(+)-Arctigenin,a lignan from Wikstroemia indica

A new lignan, (+)-aretigenin has been isolated from the roots of Wikstroemia indica (Nan-Ling-Jao-Hua) and identified as 8(R) 8′(S)-4′-hydroxy-3, 4,3′-trimethoxylignan-olid (9, 9′) on the basis of spectral evidence as well as a direct comparison with its enantiomer, (?)-arctigenin.     

Coumarins and other components of Daphne oleoides Schreb. subsp. oleoides from Majella National Park

The present study reports about the phytochemical analysis of a sample of Daphne oleoides Schreb. subsp. oleoides (family Thymelaeaceae) collected from the Majella National Park. Twenty components, belonging to different classes of natural products, have been identified by means of spectroscopic and spectrometric techniques: [monomeric (4), bis- (5, 7–10, 20) and trimeric coumarins (11), including aglycones and glycosides, coumarinolignoid (6); flavonoids (16–19); glycosidic furolignans (14, 15), glucosidic phenylpropanoids (12, 13), cyclic tetrapyrrole derivatives (2, 3), unsaturated triglyceride (1)]. Besides the chemosystematic markers of the genus (4–10, 12, 14–18, 20) several other components were identified for the first time in the species (17, 20) and/or in the Daphne genus (1–3, 13, 19). The observed composition was discussed from the chemotaxonomic standpoint and compared with those recognized from a Sardinian accession. It was observed a pronounced difference in the two metabolites patterns, most probably attributable to geographic isolation of the studied populations and, in some extent, also by the different environmental conditions, evidencing a possible tendency of D. oleoides to the infraspecific chemovariability. Considering the wide traditional uses of Daphne spp. in ethnomedicine of several countries, also the pharmacologic potential of the identified secondary metabolites is discussed.     

Early blooming's challenges: extended flowering season, diverse pollinator assemblage and the reproductive success of Gynodioecious Daphne laureola

BACKGROUND AND AIMS: The scarcity and unpredictability of active pollinators during late winter in temperate areas tends to favour extended flowering seasons and increased floral longevity in early blooming species, which are usually pollinated by diverse sets of insects. Daphne laureola is a gynodioecious woody perennial that flowers from January to April in southern Spain, a period characterized by cold temperatures, frequent rains and irregular snowfalls. METHODS: Pollinators were excluded at four different times during the flowering season in order to determine the effect of decreased exposure to pollinators on fruit set in female and hermaphrodite individuals. The role of nocturnal and diurnal pollination on reproductive success in each gender was simultaneously evaluated by selective exclusion. KEY RESULTS: A 50 % reduction in the flowering period decreased fruit set of females by 50 %, whereas the corresponding decrease in self-compatible hermaphrodites was only approx. 25 %. Day-active hymenopterans and lepidopterans were infrequent visitors, and nocturnal pollinators were inefficient, suggesting that pollen beetles, Meligethes elongatus, were the main pollinators of D. laureola in the study region. CONCLUSIONS: Beetles were less abundant in pollenless females, although discrimination did not apparently result in pollination limitation of female reproduction. A preference of beetles for sunny locations emphasized the relevance of abiotic conditions for pollination of this early blooming shrub.     

In vitro propagation of seven <Emphasis Type="Italic">Daphne</Emphasis> L. species

Cultures of seven Daphne species: Daphne caucasica, D. cneorum, D. giraldii, D. retusa, D. jasminea, D. laureola and D. tangutica were established in vitro on MS/WPM based media. Five of the species responded best on MS-based media (D. tangutica, D. laureola, D. caucasica, D. retusa and D. giraldii), while the remaining two species performed best on WPM-based media (D. cneorum, and D. jasminea). Shoot proliferation was achieved from both apical and nodal explants. Shoots were sub-cultured from stock cultures, cut into nodal explants 3–5 cm long and place vertically on basal media supplemented with different concentrations and combinations of cytokinins and auxins. Individual species displayed different responses to the various cytokinins and auxins. Among species, D. jasminea produced the greatest proliferation rate with an average of 7.84 + 0.6 shoots per explant on WPM supplemented with 2.32 μM BA + 0.0045 μM TDZ + 0.054 μM NAA, while the best multiplication rate for the same species grown on the same media supplemented with a single cytokinin (BA) and no auxin was 2.60 + 1.3 shoots per explant. Following multiplication, new shoots transferred to the elongation trails and then 50–100 mm Shoots used for rooting experiments. Increased rooting efficiencies were observed on in vitro-generated shoots with the two-layer medium or dipping methods over when PGRs were uniformly incorporated into the medium. Maximum rooting frequencies (average) ranged from 59% in D. tangutica to 85% in D. jasminea. Following in vitro rooting, rooted shoots immersed in 0.01% solution of humates and planted into a standard horticultural substrate composed and watered weekly with a solution containing half-strength MS salts.     

藏东瑞香茎叶化学成分的研究

运用各种色谱分离方法对藏东瑞香（Daphne bholua）地上部分的乙醇提取物进行分离纯化,从中分离得到12个化合物。通过波谱学数据并与已知化合物数据作比较,它们分别鉴定为：木犀草素（1）、芫花素（2）、芫花素5-O-β-D-葡萄糖苷（3）、3＇-羟基-芫花素（4）、3＇-甲氧基．芫花素（5）、异新狼毒素（6）、Genkwanol B（7）、Oleo-daphnone（8）、阿魏醛（9）、香草醛（10）、对羟基苯甲酸乙酯（n）移谷甾醇（12）。所有这些化合物都为从该植物中首次分离鉴定。     

Character of Leaf Epidermis and Their Systematic Significance of Daphne and Wikstroemia (Thymelaeaceae)

Fifty six species (varieties) of Daphne, forty five species (varieties) of Wikstroemia and twelve species of outgroups from Thymelaeaceae, with ten phenotypic characters were selected, to study the leaf epidermal microfeatures by using light microscopy, Results reveal that Daphne and Wikstromia are consistent in most of leaf features. The epidermal cell are polygonal and irregular in shape. The patterns of anticlinal wall are straight, curved and U shape. The cell sizes range in 30-40μm × 10-20μm. Some species have singly hair on surface. Stomatal distribution is random, size range in 20-36μm × 17-25μm, most are broadly elliptical and narrowly elliptical, stomatal frequency are 100-250S/mm2, and the anomocytic stomatal type is dominate. It is apparently that many stomatal and epidermal features in Daphne and Wikstromia are crossed, and no distinguishable features are suitable for separating this two genera. Results from epidermal characters analysis don’t support monophyletic status of Daphne and Wikstroemia. Eriosolena should not be include in the genus Daphne as the special papillae only found in Eriosolena composita rather than in other genera of Thymeleaceae. In compare with other genera, Rhamnoneuron, Eriosolena, Stelleropsis, Daphnopsis and Edgeworthia in Thymelaeoideae, Daphne and Wikstroemia might be derived and originated latter based on the stomatal features.