共查询到16条相似文献,搜索用时 180 毫秒
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目的研究鱼腥草中黄酮类成分的有效提取方法。方法采用改良流体萃取法提取鱼腥草中黄酮类化合物,优选最佳提取工艺,并进行含量测定。结果乙醇浓度50%,乙醇溶液流量1.8ml/分钟,温度70℃。萃取时间为27分钟,萃取率为3.15%,总黄酮含量为24.0%,其中芦丁、金丝桃苷、槲皮苷、槲皮素的萃取率分别为0.35%mg/g,1.52%mg/g,1.70%mg/g,0.50mg/g。结论鱼腥草中黄酮类成分的改良流体萃取法效果明显,值得推广。 相似文献
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Suppressive effects of Houttuynia cordata Thunb (Saururaceae) extract on Th2 immune response 总被引:1,自引:0,他引:1
ETHNOPHARMACOLOGICAL RELEVANCE: Houttuynia cordata Thunb (Saururaceae), known as 'E-Sung-Cho' in Korea, has been traditionally used for the treatment of herpes simplex, chronic sinusitis, and allergy. AIM OF THE STUDY: To investigate the inhibitory activity of Houttuynia cordata Thunb fractions (HcFs) on the T helper 2 (Th2) immune response, we evaluated the alternation of the release of Th2-type cytokines and chemokines such as interleukin (IL)-4 and IL-5, and thymus and activation-regulated chemokine (TARC/CCL17). MATERIALS AND METHODS: Ethanol fraction was obtained from dried and powdered whole plants of Houttuynia cordata Thunb using ethanol. The residue was diluted with water and was then successively partitioned with n-hexane, EtOAc and BuOH. HcFs include ethanol, n-hexane, EtOAc, BuOH and water fractions. RT-PCR and ELISA were performed to measure mRNA and protein expression of cytokines. RESULTS: HcFs inhibited the expression of IL-4 and IL-5 in response to phorbol 12-myristate 13-acetate (PMA) and calcium ionophore (CaI) in Jurkat T cells and the human mast cell line, HMC-1. IL-4- and tumor necrosis factor-alpha (TNF-alpha)-induced TARC production was blocked by HcFs in skin fibroblast CCD-986sk cells, particularly by the ethanol extract of Hc. Stimulants included in PMA, phytohemagglutinin (PHA) and CaI, increased the mRNA level of CC chemokine receptor 4 (CCR4), a receptor of TARC, in Jurkat T cells, and the ethanol extract of HcF weakly blocked the increased mRNA level. However, the stimulants and ethanol extract had no effect on the CCR4 protein level. The ethanol extract inhibited TARC-induced migration, as well as basal migration of Jurkat T cells. CONCLUSIONS: This study may show the usefulness of HcFs in the ethnopharmacological treatment of Th2-mediated or allergic inflammation, through the down-regulation of the production of Th2 cytokines and TARC, as well as cell migration. 相似文献
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