Two polyacetylenic phytoalexins from Arctium lappa

Treatment of sliced burdock root tissue with copper (II) sulphate stimulated phytoalexin formation. Two were isolated and characterized as (S)-12,1     

牛蒡幼苗基本成分测定分析

牛蒡含有多种氨基酸,且含有苏氨酸、缬氨酸、亮氨酸、异亮氨酸、苯丙氨酸、赖氨酸以及组氨酸和精氨酸必需氨基酸和半必需氨基酸。必需氨基酸含量占总氨基酸含量的26.59%。无机元素测定结果表明,牛蒡含有16种化学元素,其中铁含量高达1560.4mg/kg,明显高于其它野生植物。     

A quantitative assay for total fructans in burdock (Arctium spp.) roots

A quantitative assay of the total content of polysaccharides (fructans) in burdock roots in fructose equivalent has been elaborated. Extraction of free carbohydrates and polysaccharides has been studied using spectrophotometry and quantitative HPTLC. The optimal parameters for extracting the target group of compounds have been determined. Metrological analysis of the elaborated assay has been performed. It has been shown that the detection error does not exceed 3%.     

Hepatoprotective effects of Arctium lappa Linne on liver injuries induced by chronic ethanol consumption and potentiated by carbon tetrachloride

Arctium lappa Linne (burdock) is a perennial herb which is popularly cultivated as a vegetable. In order to evaluate its hepatoprotective effects, a group of rats (n = 10) was fed a liquid ethanol diet (4 g of absolute ethanol/ 80 ml of liquid basal diet) for 28 days and another group (n = 10) received a single intraperitoneal injection of 0.5 ml/kg carbon tetrachloride (CCl(4)) in order to potentiate the liver damage on the 21st day (1 day before the beginning of A. lappa treatment). Control group rats were given a liquid basal diet which did not contain absolute ethanol. When 300 mg/kg A. lappa was administered orally 3 times per day in both the 1-day and 7-day treatment groups, some biochemical and histopathological parameters were significantly altered, both in the ethanol group and the groups receiving ethanol supplemented with CCl(4). A. lappa significantly improved various pathological and biochemical parameters which were worsened by ethanol plus CCl(4)-induced liver damage, such as the ethanol plus CCl(4)-induced decreases in total cytochrome P-450 content and NADPH-cytochrome c reductase activity, increases in serum triglyceride levels and lipid peroxidation (the deleterious peroxidative and toxic malondialdehyde metabolite may be produced in quantity) and elevation of serum transaminase levels. It could even restore the glutathione content and affect the histopathological lesions. These results tended to imply that the hepatotoxicity induced by ethanol and potentiated by CCl(4) could be alleviated with 1 and 7 days of A. lappa treatment. The hepatoprotective mechanism of A. lappa could be attributed, at least in part, to its antioxidative activity, which decreases the oxidative stress of hepatocytes, or to other unknown protective mechanism(s).     

Isolation and Characterization of a Xyloglucan from Gobo (Arctium lappa L.)

A xyloglucan was isolated from the 24% KOH extract of gobo (edible burdock, Arctium lappa L.). A methylation analysis and enzymic degradation studies on the polysaccharide showed that gobo-xyloglucan was built up predominantly of repeating-oligosaccharide units of hepta-(Glc: Xyl=4: 3), nona- (Glc: Xyl: Gal: Fuc=4: 3: 1: 1) and deca- (Glc: Xyl: Gal: Fuc=4: 3: 2: 1) saccharides in an approximate molar ratio of 14: 12: 5, which are the typical structural units of dicot xyloglucans.     

Resource limitation of tephritid flies on lesser burdock,Arctium minus (Hill) Bernh. (Compositae)

Summary The intensity of resource exploitation by phytophagous insects is usually considered to reflect population size. For populations of two flowerhead-attacking tephritid flies, however, the resources utilised were not related to the numbers of searching adults. Tephritis bardanae Schrank attacked 11–13% of the total flowerheads each year, and Cerajocera tussilaginis (Fab) 17–65%, despite much wider and uncorrelated variation in adult numbers. Analysis of field data showed that the proportion of flowerheads used was not limited by poor flowerhead quality, but was restricted by (1) the synchronisation of adult activity with the appearance of flowerheads at the correct age for oviposition, and (2) by factors which influenced the ability of female flies to locate available heads. These restrictions were more severe in T. bardanae and explained its relatively low rate of infestation. Both tephritids tended to avoid flowerheads in open areas. The processes governing resource exploitation in each tephritid operated independently of the other, and a partial separation of the two species between flowerhead types and habitats arose simply because of their different timing of attack.     

Isolation and identification of arctiin and arctigenin in leaves of burdock (Arctium lappa L.) by polyamide column chromatography in combination with HPLC-ESI/MS

A simple method involving polyamide column chromatography in combination with HPLC-PAD and HPLC-ESI/MS for isolating and identifying two kinds of lignans, arctiin and arctigenin, in the leaves of burdock (Arctium lappa L.) has been established. After extraction of burdock leaves with 80% methanol, the aqueous phase of crude extracts was partitioned between water and chloroform and the aqueous phase was fractionated on a polyamide glass column. The fraction, eluting with 100% methanol, was concentrated and gave a white precipitate at 4 degrees C from which two main compounds were purified by semi-preparative HPLC. In comparison with the UV and ESI-MS spectra and the HPLC retention time of authentic standards, the compounds were determined to be arctiin and arctigenin. The extraction/separation technique was validated using an internal standard method.     

A biologically active fructan from the roots of Arctium lappa L., var. Herkules

From the roots of Arctium lappa L., var. Herkules a low-molecular-weight fructofuranan of the inulin-type has been isolated by water extraction and ethanol precipitation, followed by ion-exchange chromatography and gel filtration of the crude precipitate. The methods employed in structural determination were methylation analysis and 1H and 13C NMR spectral measurements. In tests for antitussive activity in cats the fructan was found to be equally active as some non-narcotic, synthetic preparations used in clinical practice to treat coughing, and in mitogenic and comitogenic tests its biological response was comparable to that of the commercial Zymosan immunomodulator.     

Latitudinal trends in herbivory and performance of an invasive species, common burdock (Arctium minus)

Plants often lose natural enemies (herbivores and pathogens) while invading new geographic regions, as predicted by the Enemy Release Hypothesis. However, a similar reduction in attack might occur at a more local scale within an invader’s range as plants in marginal areas escape enemies that fail to find them or cannot maintain local populations. In this study, we test the hypothesis that isolated populations near the northern edge of an invader’s range escape the enemies present in more southern populations, using the non-native monocarpic biennial, common burdock (Arctium minus), as a model species. In southern Ontario, this plant is attacked by a wide range of insect herbivores, including generalist leaf chewers as well as leaf-mining flies (Liriomyza arctii, Calycomyza flavinotum) and an abundant lepidopteran seed predator (Metzneria lappella). Surveys over an 815 km transect from temperate southern to boreal northern Ontario indicate that damage by all of these enemies declines sharply with latitude, while plants in more northern areas are slightly larger and more fecund. Critically, seed parasitism drops from more than 85 % in the south to less than 25 % in the north. These results indicate that populations of Arctium near this species’ northern limit escape many of their usual natural enemies, potentially counteracting less favourable environmental conditions. Such escape from enemies near invaders’ range margins may accelerate further spread, including expected migration in response to climate change.     

Natural lignans from Arctium lappa modulate P-glycoprotein efflux function in multidrug resistant cancer cells

Arctium lappa is a well-known traditional medicinal plant in China (TCM) and Europe that has been used for thousands of years to treat arthritis, baldness or cancer. The plant produces lignans as secondary metabolites which have a wide range of bioactivities. Yet, their ability to reverse multidrug resistance (MDR) in cancer cells has not been explored. In this study, we isolated six lignans from A. lappa seeds, namely arctigenin, matairesinol, arctiin, (iso)lappaol A, lappaol C, and lappaol F. The MDR reversal potential of the isolated lignans and the underlying mechanism of action were studied using two MDR cancer cell lines, CaCo2 and CEM/ADR 5000 which overexpress P-gp and other ABC transporters. In two-drug combinations of lignans with the cytotoxic doxorubicin, all lignans exhibited synergistic effects in CaCo2 cells and matairesinol, arctiin, lappaol C and lappaol F display synergistic activity in CEM/ADR 5000 cells. Additionally, in three-drug combinations of lignans with the saponin digitonin and doxorubicin MDR reversal activity was even stronger enhanced. The lignans can increase the retention of the P-gp substrate rhodamine 123 in CEM/ADR 5000 cells, indicating that lignans can inhibit the activity of P-gp. Our study provides a first insight into the potential chemosensitizing activity of a series of natural lignans, which might be candidates for developing novel adjuvant anticancer agents.     

Callus induction and high-frequency plant regeneration from hypocotyl and cotyledon explants of Arctium lappa L.

Summary This study describes a protocol for plant regeneration from cultured seedling explants of Arctium lappa. Hypocotyls and cotyledons of A. lappa were induced to form callus by culturing on Murashige and Skoog (MS) medium supplemented with 2.0mg l^−1 2,4-dichlorophenoxyacetic acid and 0.5–2.0 mg l^−1 benzyladenine (BA). Formation of adventitious buds could be induced from calluses or explants directly by culturing on MS medium containing 1.0–2.0 mg l^−1 α-naphthaleneacetic acid (NAA) and 0.5–2.0 mg l^−1 BA. These regenerated shoots were rooted on MS medium with 1.0 mg l^−1 indole-3-butyric acid or indole-3-acetic acid in combination with 1.0 mgl^−1 NAA. The regenerated plants acclimatized in soil were normal morphologically and in growth characters. They flowered and set seeds in the following year after acclimatization.     

Stereochemical Difference in Secoisolariciresinol Formation between Cell-free Extracts from Petioles and from Ripening Seeds of Arctium lappa L.

Cell-free extracts from ripening seeds of Arctium lappa L. catalyzed the enantioselective formation of (-)-pinoresinol, (-)-lariciresinol and (-)-secoisolariciresinol from achiral coniferyl alcohol in the presence of NADPH and H₂O₂. The enantioselectivity of the lignan formation was opposite to that of the (+)-secoisolariciresinol formation catalyzed by cell-free extracts from petioles of the same plant species.     

伊犁地区野生毛牛蒡与牛蒡的成分分析比较研究

对伊犁地区野生牛蒡属两种植物,即牛蒡和毛牛蒡根的主要营养及保健成分和主要矿质元素进行了分析,发现毛牛蒡和牛蒡的主要成分没有显著差异（P〈0．05）,说明毛牛蒡也是一种药食两用的野生资源。     

Seed production and predispersal seed predation in the biennial composite species,Arctium minus (Hill) Bernh. and A. lappa L.

Summary Comparison was made of the seed production of two species of burdock, Arctium minus (Hill) Bernh. and A. lappa L., which are found in a variety of recently disturbed habitats throughout Waterloo County, Ontario. The mean number of seeds per plant of A. minus was significantly greater, 13,400 compared with 8,200 seeds in A. lappa. The mean number of heads per plant was also greater for A. minus than for A. lappa, 338 versus 112 heads respectively. Above-ground biomass allocated to reproductive heads was similar in A. minus (44.2%) and A. lappa (43.7%). Significant variation in the mean number of seeds per head was observed in A. minus, ranging from 29.0 to 47.1. The between-plant variation in this character is significantly greater than the variation between populations from various sites.Predispersal seed predation by the microlepidopteran Metzneria lappella (Fam. Gelechiidae) resulted in 28% to 71% loss of seeds of A. minus at different sites. The observed loss in A. lappa was dramatically lower at 15.5%. The number of seeds attacked by one larval predator varied from 2 to 15 with means from 7 to 9. In addition, great variation in the number of seeds and the number of predators per head was observed. Larvae were randomly distributed among the heads at 4 of 7 sites and aggregated at the other sites. Seed predation per head greater than 60% was found with the aggregated larval distributions. Only rarely was the number of seeds attacked by a larva associated with the number of larvae in the head. The winter dispersal of heads of A. minus was much lower than that for A. lappa, 62.2% and 21.0% respectively. Also, the dispersal of seeds from heads differed between the two species. Only 21.8% of the seeds of A. minus were lost compared with a seed dispersal rate of 56.5% for A. lappa.     

Inhibitory Effect of Supercritical Extracts from Arctium lappa L. on the Lectin Pathway of the Complement System

The complement system participates in host defense by eliminating microorganisms and triggering inflammation. However, insufficient control or exacerbated complement activation contributes to inflammatory diseases. Since promising antioxidant and anti‐inflammatory activities have been identified in Arctium lappa L. extracts, this study aims to explore the effect of A. lappa extracts on the lectin pathway (LP) of complement activation. Four extracts were obtained by supercritical extraction using scCO₂ with or without ethanol as co‐solvent, at different temperatures and pressures (E1: 2.2 mg/mL, E2: 2.6 mg/mL and E3: 2.0 mg/mL, E4: 1.5 mg/mL). To evaluate the effect of A. lappa extracts on the LP activation, an ELISA assay using mannose binding lectin pathway of complement was carried out with C4 detection. All extracts showed a concentration‐dependent inhibitory effect on the activation of complement by the LP. The following IC₅₀ were observed for E1, E2, E3 and E4: 179.4 μg/mL, 74.69 μg/mL, 119.1 μg/mL and 72.19 μg/mL, respectively. Our results suggest that A. lappa extracts are potential candidates for the treatment of inflammatory disorders that are complement‐related.     

A new cell line from the wax moth Galleria mellonella Linne (lepidoptera: Pyralididae)

Summary A cell line derived from the larval-fat body tissues of the wax moth, Galleria mellonella Linne, was established in MGM-450 medium. The cells grew in suspension and were mainly spherical in shape. Population doubling time was between 1.4 and 1.7 d over a range of 15 to 35°C, and the maximum growth rate was at 25°C. The chromosome number ranged from 70–239, with a mode of 170. The cells were sensitive to 20-hydroxyecdysone, which stimulated their growth and induced morphological changes. The cell line was designated GaMe-LF1.     

牛蒡L1-2组分对桔全爪螨的毒性和几种代谢酶的作用

【目的】探讨杀螨植物牛蒡Arctium lappa L.提取物中主要杀螨成分L1-2的杀螨作用机理。【方法】采用叶片浸渍法处理桔全爪螨Panonychus citri雌成螨后,测定了静止期、兴奋期、痉挛期、麻痹期、复苏和死亡期5个中毒阶段试虫体内几种代谢酶的活性。【结果】L1-2组分在静止期和复苏期对羧酸酯酶（carboxylesterase, CarE）具有一定的抑制作用,在其他时期均激活CarE活性。除了静止期外,在其他时期均能激活乙酰胆碱酯酶（acetylcholinesterase , AChE）和谷胱甘肽转移酶（glutathione S-transferases, GSTs）的活性,在痉挛期和麻痹期活性增强,随后在麻痹期和复苏期降低。【结论】L1-2组分对CarE的抑制与其毒杀活性有关,而中毒试虫的复苏可能与AChE和GSTs有关。该组分可在较长时期内影响桔全爪螨的神经传导及消化和生殖系统,具有潜在的应用研究价值。     

A probable new adhesive factor (F42) produced by enterotoxigenic Escherichia coli isolated from pigs

Three enterotoxigenic Escherichia coli (ETEC) strains (coded 62, 104, and 567/7) isolated from piglets with neonatal diarrhea produced only a thermostable enterotoxin. Although these strains showed mannose-resistant microhemagglutination (MRMH), the responsible factor was serologically different from the known hemagglutinating colonization factors from porcine strains (K88, K99, and F41). Bacterial cells from these strains adhered to HeLa cells and pig brush borders. Electron microscope studies revealed the presence of fimbria-like structures on bacterial cells grown at 37 C but not on cells grown at 18 C. The antiserum prepared from partially purified fimbrial antigen (provisionally called F42) inhibited chicken erythrocyte MRMH caused by these strains as well as adherence of strain 567/7 to HeLa cells and to pig brush borders. These data taken together suggest the existence of a new hemagglutinating adhesin that is different from those so far described for porcine ETEC.