Phenylethanoid glycosides from Phlomis integrifolia Hub.-Mor

Two new phenylethanoid glycosides integrifoliosides A (2) and B (3), along with a known phenylethanoid glycoside alyssonoside (1) and a flavone glucoside chrysoeriol-7-O-beta-D-glucopyranoside (4) were isolated from the aerial parts of Phlomis integrifolia. The structures of the new compounds were identified as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1 --> 4)-alpha-L-rhamnopyranosyl-(1 --> 3)-4-O-feruloyl-beta-D-glucopyranoside (2) and 3-hydroxy-4-methoxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1 --> 4)-alpha-L-rhamnopyranosyl-(1 --> 3)-4-O-feruloyl-beta-D-glucopyranoside (3), on the basis of spectroscopic (UV, IR, 1D- and 2D-NMR, and HR-FABMS) methods.     

Temperature relations of photosynthetic response in populations of Verbascum thapsus L.

Summary Seedlings representative of Verbascum thapsus L. populations from thermally diverse habitats were grown under uniform, controlled conditions. The plants were used to obtain temperature response curves for net photosynthesis over a range of 15–40°C. In general, all experimental plants exhibited similar rates of net photosynthesis at 20, 25, 30, and 35°C. Plants representative of cool habitat populations (high-latidude and high-altitude) had greatest rates of net photosynthesis at the lower temperatures and much lower rates at 40°C. Plants representative of warm habitat populations (low-latitude and low-altitude) exhibited rates of net photosynthesis at 40°C which were nearly twice those of plants representative of cool habitat populations. Carbon dioxide transfer resistances are discussed with reference to plant control of photosynthesis at different temperatures. Patterns of photosynthesis and resistance response among plants representative of different habitats suggest ecotypic variation has occurred only to a very limited extent. Therefore, the patterns exhibited by experimental plants suggest that Verbascum thapsus' success in a number of diverse sites is related to the ability of all members of the species to photosynthesize over a broad range of temperatures.     

Phenylethanoid glycosides from Lippia javanica

Lippia javanica (N.L.Burm.) Spreng. is an aromatic, multipurpose medicinal plant from which a number of volatile compounds have been identified, together with toxic triterpenoids and iridoid glycosides. Two additional phenylethanoid glycosides, verbascoside and isoverbascoside, were isolated from L. javanica and characterized. High performance liquid chromatography analyses of polar extracts of three other Lippia species (L. scaberrima, L. rehmannii and L. wilmsii), indigenous to South Africa, revealed the presence of both isomers. When compared to the other indigenous Lippia species, the leaves of L. javanica were found to contain the highest concentrations of both isomers. In addition, the intraspecies variation of the verbascoside/isoverbascoside content of L. javanica, harvested from the same and different localities, was investigated. The concentrations of the two phenylethanoids remained fairly consistent within and between different populations, even when geographically separated. While these compounds are produced by many genera, they may now be added to the list of iridoid glucosides employed as chemotaxonomic markers for Lippia species.     

Phenylethanoid and aliphatic alcohol glycosides from Acanthus ilicifolius

A phenylethanoid glycoside (ilicifolioside A) and an aliphatic alcohol glycoside (ilicifolioside B), have been isolated from the aerial parts of Acanthus ilicifolius, together with eight known compounds. Their structures were determined from spectroscopic analyses.     

毛蕊花和粟米草毛状根培养系统的建立(简报)

用发根农杆菌Ａ４、Ｒ１６０１、ＡＴＣＣ１５８３４从毛蕊花和粟米草的无菌子叶中诱导出毛状根,经高压纸电泳鉴定,这两种毛状根中均含有甘露碱,并测定了它们的生长曲线。     

Fitness consequences of branching in Verbascum thapsus (Scrophulariaceae)

The reserve meristem hypothesis proposes that strong apical dominance suppresses lateral meristems and branches to escape from predictable damage (herbivory). This hypothesis was tested for Verbascum thapsus and its seed predator the weevil Gynmnetron tetrum by two mensurative experiments. The following predictions were made under this hypothesis: the proportion of individuals branched within a population will increase with increased damage, the main stalk of branched plants will be more damaged, and branching increases net seed production. Fifty populations of V. thapsus were extensively surveyed, and one pair of similar-sized individuals (branched vs. unbranched) were selected from each population to determine damage patterns and measure seed production. Two of the predictions of the reserve meristem hypothesis were clearly supported. The proportion of fruits damaged on the main stalk of branched plants was significantly greater than unbranched plants, and branched plants produced significantly more seeds. Hence, the reserve meristem hypothesis is supported as an adaptive interpretation of apical dominance in this species. This study is a potential example of overcompensation following granivory in the field.     

Phenylethanoid glycosides from the leaves of Magnolia hodgsonii

Three new phenylethanoid glycosides, 2-(3-hydroxy-4-methoxyphenyl)ethyl 1-O-β-d-allopyranoside (hodgsonialloside A, 1), 2-(3-hydroxy-4-methoxyphenyl)ethyl 1-O-β-d-glucopyranosyl-(1 → 4)-β-d-allopyranoside (hodgsonialloside B, 2) and 2-(3-methoxy-4-hydroxyphenyl)ethyl 1-O-β-d-allopyranoside (hodgsonialloside C, 3) were isolated from the leaves of Magnolia hodgsonii in addition to six known compounds, tyrosol 4-O-β-d-xylopyranosyl-(1 → 6)-β-d-glucopyranoside (4), kaempferol 3-O-neohesperidoside (5), kaempferol 3-O-rutinoside (6), kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (7), (+)-syringaresinol O-β-d-glucopyranoside (8), and oblongionoside C (9). The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments.     

Phenylethanoid and secoiridoid glycosides from the leaves of Ligustrum purpurascens

A new phenylethanoid glycoside (2) and a new secoiridoid glycoside (16) were isolated from the leaves of Ligustrum purpurascens together with fourteen known compounds (1 and 3–15). The structures of the new compounds were determined by spectroscopic analyses (UV, IR, HR-ESI-MS, 1D, and 2D NMR). The absolute configuration of 16 was further determined by CD analysis. All phenylethanoid glycosides were prepared and their up-regulation of IFN-γ production in mouse splenic lymphocytes was evaluated. Compounds 1, 5, 6, 10, 11, 13 and 15 exhibited potent stimulatory effect on IFN-γ secretion.     

In vitro culture of common mullein (Verbascum thapsus L.)

Summary Verbascum thapsus L. is a medicinal herb and has been used to treat inflammatory disease, asthma, spasmodic coughs and migraine headaches. Studies were initiated to establish an in vitro culture protocol for V. thapsus. Explants (leaf dises, petioles and roots) were cultured on Murashing and Skoog minimal organics (MSMO) medium with benzyladenine (BA) or kinetin. Best shoot proliferation was obtained from leaf dise and petiole explants at 13.32 μM BA. Leaf dises were cultured on MSMO medium with 13.32 μM BA in combination with naphthalene acetic acid (NAA) or 2,4-dichlorphenoxyacetic acid (2,4-D). More shoot development was obtained with 13.32 μM BA and 5.37 μM NAA. Shoots were transferred to rooting media containing different levels of NAA and 2,4-D. Most of the shoots formed roots on media with 5.37 μM NAA. Plants were transferred to vermiculite and subsequently to potting media and maintained in the greenhouse.     

A test of the reserve meristem hypothesis using Verbascum thapsus (Scrophulariaceae)

The reserve meristem hypothesis predicts that latent meristems may act as a bet-hedging strategy given high-cost, predictable herbivory. Under this hypothesis, damage to a plant should elicit greater branching. This prediction was tested in Verbascum thapsus with three experiments manipulating the intensity and type of damage to reproductive tissue. In the first experiment, seed set was prevented in the treatment group by stigma excision and lanolin application to 80% of the flowers of each plant. In the second experiment, a minimum of two mating pairs of weevils were added to treated plants prior to the onset of flowering. In the third experiment, all fruits were sliced lengthwise twice. All three treatments significantly reduced seed set. In the first two experiments, treated plants significantly increased degree of branching (branch number and total branch length). This supports the reserve meristem hypothesis as an explanation for greater branching in larger plants of V. thapsus. Interestingly, the fruit destruction experiment failed to elicit a branching response, which suggests that the timing of damage is important.     

Pollination in Verbascum thapsus (Scrophulariaceae): the advantage of being tall

According to the "effective pollination" hypothesis, tall stature resulting from strong apical dominance attracts greater pollinator visitation, thus allowing larger pollen loads and/or greater outcrossing rates, which in turn produces more vigorous offspring with greater genotypic variability and/or less inbreeding depression. Components of this hypothesis were tested in Verbascum thapsus, which commonly grows unbranched to over 2 m tall with strong apical dominance suppressing all axillary meristems. A natural population survey indicated that plants with visiting pollinators were significantly taller than their nearest neighboring individuals not possessing a visiting pollinator. Plants in natural populations with excluded pollinators produced seeds via a delayed selfing mechanism. However, delayed selfing under pollinator exclusion resulted in only 75% of the seed set obtained with natural pollinators. Under natural pollination, emasculated flowers experienced a 50% reduction in pollen deposition by the time of flower closure but only a 5% reduction in seed set relative to intact flowers. Hence, taller plants attracted more pollinators and maximum seed set could not be achieved without pollinators. Comparison of seed set and seed mass in plants that were artificially selfed and artificially crossed (in both the greenhouse and in natural populations) indicated that plants were fully self-compatible with no evidence of early-acting inbreeding depression. However, this does not exclude the possibility that inbreeding depression is manifested in later life stages. The results suggest that V. thapsus has a mixed mating system with potential for reproductive assurance and various levels of outcrossing depending on variables affecting pollinator availability (e.g., population size).     

Antinociceptive and anti-inflammatory effects of saponin and iridoid glycosides from Verbascum pterocalycinum var. mutense Hub.-Mor

The anti-inflammatory and antinociceptive properties of four major compounds from the flowers of Verbascum pterocalycinum var. mutense were investigated. Saponin glycosides called ilwensisaponin A and C and iridoid glycosides known as ajugol and picroside IV were isolated from the methanolic extract. A dose-related anti-inflammatory and antinociceptive response were obtained in this study at doses of 100 and 200 mg/kg. The results of the evaluation of the anti-inflammatory activity induced by carrageenan and PGE1 showed that this species possesses active constituents that could diminish the cyclooxygenase activitiy. No effects were observed in the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema model. Our results support the anti-inflammatory and analgesic effects of Verbascum pterocalycinum var. mutense. Ilwensisaponins A and C could explain in part the anti-inflammatory and analgesic activities of this species. Although antinociceptive and anti-inflammatory activities of ajugol and picroside IV were found insignificant in the statistical analysis, ilwensisaponin A and C showed notable activity without inducing any apparent acute toxicity as well as gastric damage.     

New lignan glycosides from the root barks of Litsea glutinosa

An investigation on the chemical constituents in the root barks of Litsea glutinosa was performed for the first time. Three new lignan glycosides named Litseasins A–C (1–3), together with a known one (4), were obtained. The structures of the new compounds were established through extensive spectroscopic analyses including HR-ESI–MS, NMR, and circluar dichroism (CD). The new compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induce nitric oxide (NO) production in RAW264.7 murine macrophage cells. However, these compounds showed no inhibition on LPS-induced NO productions.     

秦巴山区野生绞股蓝枝叶中多糖提取工艺的优化

采用微波辅助法提取秦巴山区野生绞股蓝枝叶中的多糖,用苯酚-硫酸法测定多糖含量。选取酸碱度、料液比、微波温度和微波时间作为提取因素,通过单因素实验和L9(34)正交试验来优化绞股蓝枝叶中的多糖提取工艺。结果表明,野生绞股蓝枝叶中多糖的最佳提取条件为pH 9,料液比1∶20,微波温度60℃,微波处理时间15min,在此工艺条件下提取量高达40.10mg.g-1。     

Saponins from Verbascum nigrum.

Two triterpene saponins have been isolated from the inflorescences of Verbascum nigrum. Their structures were determined by chemical and spectral methods as 3-O-([alpha-L-rhamnosyl-(1-->4)-(beta-D-glucopyranosyl-(1-->3)]-be ta-D-glucopyranosyl]-(1-->2)-beta-fucopyranosyl)-13 beta,28-epoxyolean-11-ene-3 beta,23-diol and 3-O-([alpha-L-rhamnosyl-(1-->4)-(beta-D-glucopyranosyl-(1-->3)-bet a-D- glucopyranosyl]-(1-->2)-beta-fucopyranosyl)-11-methoxy-olean-12-en e-3 beta,23,28-triol.     

Influence of low temperature on phosphatase in roots of Verbascum thapsus,a biennial weed

The temperature peak (15 °C) of acid and alkaline phosphatase in this study coincides with a peak in alpha-amylase as seen in an earlier study of roots of Verbascum thapsus. It is speculated that one of the results of higher phosphatase activities may be increased amount of orthophosphate which can be utilized in phosphorylation of soluble carbohydrates which in turn are in greater supply due to the higher activities of the starch-degrading enzymes.A second peak in activities of acid and alkaline phosphatase was seen in plants which were returned to the greenhouse following cold treatment. This increase in enzymatic activities is also similar to increases in activities of three starch degrading enzymes studied earlier. Alkaline phosphatase showed greater activities than did acid phosphatase at lower temperatures (10 and 4 °C) and under greenhouse conditions following cold treatment.     

Triterpene saponins from Verbascum songaricum.

Songarosaponin A, B and C isolated from the aerial parts of Verbascum songaricum were shown to be 3-O-[alpha-L-rhamnopyranosyl-(1----4)-beta-D-glucopyranosyl-(1----3)]-[b eta-D-glucopyranosyl-(1----2)-beta-D-fucopyranosyl]-olea-11,13-die ne-3 beta-23,28-triol, 3-0-[alpha-L-rhamnopyranosyl-(1----4)-beta-D-glucopyranosyl-(1----3)]-[b eta-D-glucopyranosyl-(1----2)]-beta-D-fucopyranosyl]-olea-1 1-ene-3 beta-13,23,28-tetrol and 3-O-[beta-D-glucopyranosyl-(1----4)]-[beta-D-glucopyranosyl-(1----3)]-[b eta-D-glucopyranosyl-(1----2)]-beta-D-fucopyranosyl]-13 beta,28-epoxyolea-11-ene-3 beta,23-diol.