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排序方式: 共有347条查询结果,搜索用时 31 毫秒
1.
Three new phenylpropanoid glycosides 1–3, along with nine known phenylpropanoid glycosides 4–12, were isolated from the aerial parts of Cirsium japonicum. The structures of isolated compounds were elucidated by chemical and spectroscopic methods. Compounds 1, 3, 6, 8, and 11 showed moderate cytotoxicities against MCF-7, U87, HCT116, and A549 cell lines with IC50 values in the range of 1.35–11.32 μM. The known compounds 4–12 were obtained from this plant for the first time. 相似文献
2.
Aster spathulifolius, Coreopsis drummondii, Chrysanthemum morifolium, Chrysanthemum boreale, Chrysanthemum indicum and Rudbeckia laciniata var. hortensis had 30–70 mg gallic acid equivalents (GAE)/g dw of the total phenolic contents. Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing powers of tested Compositae plant extract appeared to be linear and consistent with total phenolic/flavonoids compound contents in the same manner with DPPH radical scavenging activity. R. laciniata (200 µg/mL) inhibited nitric oxide (NO) production to approximately 92.8% from lipopolysaccharide (LPS)-stimulated macrophage cells. Although the total phenolic/flavonoids contents and antioxidant activity of R. laciniata is low compared with other Compositae plants, R. laciniata shows the superior inhibitory activity against NO biosynthesis from LPS-induced macrophage cells. For antiobesity activity, C. boreale, C. morifolium and C. drummondii might act to accelerate lipid degradation and to decrease lipid synthesis in 3T3-L1 adipocyte cells, and C. indicum, A. spathulifolius and R. laciniata extract had antiobesity activity to inhibit lipid synthesis in 3T3-L1 adipocyte cells. 相似文献
3.
Lettuce (Lactuca sativa L.) and its varieties are important vegetable crops worldwide. They are also well‐known, rarely reported, causes of contact allergy. As lettuce allergens and extracts are not commercially available, the allergy may be underdiagnosed. The aims of this article are to present new data on lettuce contact allergy and review the literature. Lettuce is weakly allergenic, and occupational cases are mainly reported. Using aimed patch testing in Compositae‐allergic patients, two recent Danish studies showed prevalence rates of positive lettuce reactions of 11% and 22%. The majority of cases are non‐occupational, and may partly be caused by cross‐reactivity. The sesquiterpene lactone mix seems to be a poor screening agent for lettuce contact allergy, as the prevalence of positive reactions is significantly higher in non‐occupationally sensitized patients. Because of the easy degradability of lettuce allergens, it is recommended to patch test with freshly cut lettuce stem and supplement this with Compositae mix. As contact urticaria and protein contact dermatitis may present as dermatitis, it is important to perform prick–to–prick tests, and possibly scratch patch tests as well. Any person who is occupationally exposed to lettuce for longer periods, especially atopics, amateur gardeners, and persons keeping lettuce‐eating pets, is potentially at risk of developing lettuce contact allergy. 相似文献
4.
Azadeh Manayi Mahdieh Kurepaz-mahmoodabadi Ahmad R Gohari Yousef Ajani Soodabeh Saeidnia 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2014,22(1)
Background
Phthalate, esters of phthalic acid, are mainly applied as plasticizers and cause several human health and environment hazards. The essential oils of Achillea species have attracted a great concern, since several biological activities have been reported from varieties of these medicinal species. On the other side, due to the problems regarding the waste disposal in developing countries, phthalate derivatives can easily release from waste disposal to the water and soil resulting in probable absorption and accumulation by medicinal and dietary plants. As a matter of fact, although the toxicity of phthalate derivatives in human is well-known, food crops and medicinal plants have been exposing to phthalates that can be detected in their extracts and essential oils. Achillea tenuifolia (Compositea) is one of these herbaceous plants with traditional applications which widely growing in Iran.Finding
The plant root was subjected to hydro-distillation for 4 h using Clevenger type apparatus to obtain its essential oil before and after acid treatment. Both of the hydro-distilled essential oils were analysed by GC-MS method resulted in recognition of their constituent. Phthalate contamination as (1, 2-benzenedicarboxylic acid, bis (2-methylpropyl) ester (5.4%) and phthalic acid (4.5%), were identified in the first and second extracted oils, respectively.Conclusion
As a warning, due to the potential role of phthalates to cause reproductive toxicity, disturb of endocrine system and causing cancers, medicinal plants have to be considered through quality control for detection of these compounds. 相似文献5.
采用溶剂提取、萃取粗分离、硅胶和Sephadex LH-20凝胶柱色谱以及制备HPLC等纯化技术,从采自北京郊区的尼泊尔菊三七栽培品中分离得到4个化合物,通过波谱分析并参考文献数据鉴定其结构分别为7S,8R-9'-O-乙基-去氢双松柏醇-9-乙酸酯(1)、9'-O-乙基-去氢双松柏醇(2)、去氢双松柏醇-9,9'-二乙酸酯(3)和(+)-梣皮树脂醇(4)。1为新的2,3-二氢苯并呋喃-8,3'-新木脂素型化合物,2~4均为首次从尼泊尔菊三七中分离得到的木脂素类化合物。对4个化合物在DMSO-d6溶剂中的1H-和13C-NMR数据进行了全归属。 相似文献
6.
Background. Two preparations are currently in use for the diagnosis of allergic contact dermatitis caused by Asteraceae: (i) Sesquiterpene lactone (SL) mix [three pure sesquiterpene lactones (STLs)], whose use has been questioned, owing to an insufficient rate of true‐positive results; and (ii) Compositae mix, consisting of five Asteraceae extracts, which is problematic because of lack of standardization and questionable reproducibility. Objectives. To analyse the reasons for the narrow sensitivity of SL mix from a chemoinformatic point of view, and to propose a solution by rational selection of alternative constituents for a new SL mix II covering a broader cohort of allergic patients. Materials/methods. Structural and biological information on allergenic STLs was retrieved from databases and the literature, and molecular modelling and chemoinformatic computations were performed. Results. An explanation for the insufficient hit rate of SL mix is that the three constituents possess extremely similar molecular structures/properties and do not represent well the structural diversity of allergenic STLs. STLs that are known as constituents of Compositae mix plants show much a wider diversity, which explains the higher positive rate. Conclusions. On the basis of their positions in chemical property space, a new collection of STLs that more evenly cover the overall structural diversity spectrum is proposed. SL mix II is likely to detect a larger number of patients sensitized to Asteraceae. 相似文献
7.
Inhibitory Effects of Saussurea involucrata. Against Melanogenesis of Mouse-Derived Melanocyte Cells
Qing Mu Hyun-Jung Choi Li-Fei Wang Xiao-Jin Li Jae-Sung Hwang Byeong-Gon Lee 《Pharmaceutical biology》2013,51(9):678-682
AbstractExtracts and fractions from the aerial parts of herbal materials of Saussurea involucrata. Kar et Kir ex Maxim (Compositae) were investigated for their whitening activity against mouse-derived immortalized melanocyte cell line. The extract of wild herbs (FS2) possessed a better inhibition (28.2% growth) against melanin cells than that (46.7%) of cultivated herbs (FS1). The whole extracts and middle-polar partitioning fraction show the inhibitory effects, whereas the water-soluble parts show a poor activity in the same assay. 相似文献
8.
目的:研究小蓟的化学成分。方法:通过多种色谱手段进行化学成分的分离与纯化。结果:-个新的大柱香波龙烷苷和六个已知化合物被分离得到,分别是(7E,9R)-9-hydroxy-5,7-megastigmadien-4-one-9-O-α-L-arabinopyranosyl.(1-6)-β-D-glucopyanoside(1),(6R,7E,9R)-9-hydroxy-4,7-megastigmadien-3-one-9-O-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside(2),uro-lignoside(3),4,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-7-O-β-D-glucopyranoside(4),citrosideA(5),红景天苷(6),和腺苷(7)。结论:化合物1为新化合物。 相似文献
9.
Background. The development of mixes containing Compositae plant extracts has improved the diagnosis of Compositae contact allergy, but none of them has fulfilled the criteria for an ideal European plant mix. Objective. To evaluate which constituents of two commercial Compositae mixes were most useful as screening agents. Patients. These comprised 76 patients testing positive to Compositae mix 6% in petrolatum and 29 patients testing positive to Compositae mix 5% pet., all of whom were tested with constituents of the respective mixes. Results. The majority of patients tested positive to parthenolide or parthenolide‐containing extracts, followed by German chamomile, yarrow, and arnica. As German chamomile is a weak sensitizer, the results suggest cross‐reactions or reactions to unknown allergens. No one was positive to Roman chamomile. Conclusions. Even though parthenolide seems to be a suitable supplement to the baseline series, the results emphasize that it is important to patch test with extracts of native or locally grown plants, not only because of the geographical variation, but also because of the potential unknown allergens contained in short ether preparations and the variability in the individual patient's exposure and cross‐reaction patterns. 相似文献
10.
目的:研究菊科中药四气属性与药物成分和功效的关联性。方法:通过查阅相关文献资料,对菊科中药的四气属性、药物所含化学成分和传统功效进行归纳、总结,并采用两因素关联分析方法,对菊科中药的四气属性与药物所含化学成分、功效的关联性进行分析。结果:查阅到的157种菊科中药中性温者43味,占27.39%;性寒者40味,占25.48%;性凉者40味,占25.48%;性平者32味,占20.38%;性热者2味,占0.01%。其所含化学成分的类型以挥发油、黄酮、萜类、生物碱、酸类为主;菊科中药功能擅长清热解毒、散瘀止痛、祛风除湿、凉血止血等。结论:菊科中药四气属性以寒凉为主,四气属性与功效关系密切。 相似文献