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31.
Twelve compounds were isolated from Chrozophora tinctoria (L.) Raf. They were identified as kaempferol, kaempferol 3-O-β-glucopyranoside, kaempferol 3-O-(6″-α-rhamnopyranosyl)-β-glucopyranoside, quercetin, quercetin 3-O-β-glucopyranoside, quercetin 3-O-(6″-α-rhamnopyranosyl)-β-glucopyranoside, apigenin, apigenin 7-O-β-glucopyranoside, acacetin, gallic acid, methyl gallate and β-sitosterol-3-O-β-glucopyranoside. Their structures were elucidated by chemical and spectral methods. Furthermore, chemosystematics of the isolated compounds is briefly discussed. It was indicated that C. tinctoria is the only species of Chrozophora that has the capability to synthesis kaempferol aglycone and their glycosides, and the finding is supported by its distinct morphological and anatomical aspects.  相似文献   
32.
Coreopsis tinctoria, also called “snow chrysanthemum” in China, is a flower tea material that has been reported to possess excellent pharmacological properties such as antioxidant and antidiabetic activities. The chemical characteristics of different parts (flowers, buds, seeds, stems, and leaves) of C. tinctoria were investigated based on microwave‐assisted extraction and the simultaneous determination of 13 major active compounds by high‐performance liquid chromatography, including taxifolin‐7‐O‐glucoside, chlorogenic acid, (R/S)‐flavanomarein, isocoreopsin, quercetagetin‐7‐O‐glucoside, isookanin, 5,7,3′,5′‐tetrahydroxyflavanone‐7‐O‐glucoside, marein, 3,5‐dicaffeoylquinic acid, coreopsin, okanin, 5,7,3′,5′‐tetrahydroxyflavanone, and N1,N5,N10,N14‐tetra‐p‐coumaroylspermine. Chemometric analysis based on the contents of investigated compounds from 13 samples showed that C. tinctoria and the related flower tea materials, Chrysanthemum morifolium cv “Hangju” and “Gongju,” were in different clusters, and different parts (flowers, buds, seeds, stems, and leaves) of C. tinctoria were obviously different. This study is helpful for the quality control and pharmacological evaluation of different parts from C. tinctoria and its related products.  相似文献   
33.
Abstract

Seventeen compounds were isolated from the capitula of Coreopsis tinctoria Nutt. with various column chromatographic methods and semi-preparative HPLC. Their structures were identified by the spectroscopic data and comparison with literatures as 2′-hydroxy-4,4′-dimethoxy-chalcone; (1), isoliquiritigenin (2), eriodictyol (3), naringenin (4), maritimetin (5), butin (6), taxifolin (7), luteolin (8), 7,3′,4′-trihydroxyflavone (9), 8,3′,4′-trihydroxyflavone-7-O-β-d-glucoside (10), quercetin (11), quercetagitin-7-O-β-d-glucoside (12), quercetin-7-O-β-d-glucoside (13), 3,4-dihydroxybenzoic acid (14), caffeic acid (15), coreoside B (16), and myo-inositol (17). Compounds 1, 4, 9, 10 and 17 were isolated from C. tinctoria Nutt. for the first time. Compounds 7 and 12 possessed the highest antioxidant activity (IC50?=?64.37 and 32.86?µg/ml, respectively) among the tested compounds (IC50 value of positive control was 5.34?µg/ml). Compound 7 exhibited potent PTP1B enzymatic inhibition with an IC50 value of 7.73?μg/ml (IC50 value of positive control is 1.46?µg/ml). Furthermore, compound 5 showed strong antibacterial activity against the Gram-positive bacterium, S. aureus.  相似文献   
34.
外来观赏植物大花金鸡菊在中国的 潜在地理分布预测   总被引:1,自引:0,他引:1  
大花金鸡菊(Coreopsis grandiflora Hogg.)被引种后,因具有较强繁殖和适应能力,在我国山东等地区成为入侵物种,对当地植物多样性造成了一定威胁。笔者运用Maxent生态学模型,基于全球海拔变量及19个生物环境变量,结合地理信息系统ArcGIS,对大花金鸡菊在中国的潜在地理分布区做了预测。结果表明,大花金鸡菊在我国的适生范围主要集中在98°~125°E、21.5°~43°N水分充沛、温度适宜的暖温带、亚热带地区。其中,华东、华中大部,即江苏、安徽、上海市、山东等地为大花金鸡菊的集中分布区,为高适生区; 西南、华南北部与华东、华中地区相接的区域,以及华北南部邻接华东地区的局部地区为中适生区,西南、华南南部地区则为低适生区; 其他地区不适于大花金鸡菊生长。ROC 曲线分析表明,Maxent 生态位模型预测大花金鸡菊潜在地理分布的训练数据和测试数据的AUC值分别为0.960和0.965,达到了极高的精度。各环境变量重要性的刀切法检验表明,影响大花金鸡菊地理分布的环境变量依次为年均温、年平均降水量和最冷季平均温度。根据 Maxent 模型预测结果,以及大花金鸡菊的生物学特性和在中国的入侵现状,在我国中东部地区需要采取一定的有效措施对该物种的扩张进行控制。  相似文献   
35.
Chrozophora tinctoria (Euphorbiaceae) has been used as an emetic, anthelminthic, and cathartic agent in traditional medicine. We used gas chromatography-mass spectrometry (GC-MS) to characterize the composition of ethyl acetate (EAC) and dichloromethane (DCMC) fractions from the whole Chrozophora tinctoria plant. EAC and DCMC fractions were evaluated for acetylcholinesterase (AChE) inhibitory activity and acute toxicity. Their effects on intestinal propulsive movement and spasmogenic activity of the gastrointestinal tract (GIT) muscle were also assessed. The compounds detected in both fractions were mostly fatty acids, with about seven compounds in EAC and 10 in DCMC. These included pharmacologically active compounds such as imipramine, used to treat depression, or hexadecanoic acid methyl ester, an antioxidant. Both EAC and DCMC fractions inhibited acetylcholinesterase (AChE) activity with IC50 values of 10 µg and 130 µg, respectively. Both the fractions were found to be toxic in a dose-dependent manner, inducing emesis at 0.5 g or higher and lethargy and mortality from 3–5 g upwards. Similarly, both of the fractions showed laxative activity in metronidazole- and loperamide-induced constipation models. EAC relaxed the intestinal muscle at a lower dose (1 mg/mL) than DCMC. Similarly, the EAC extract showed a significant relaxation effect (EC50 = 0.67 ± 0.15 mg/mL) on KCL-induced contraction in rabbit jejunum as compared to DCMC (EC50 = 5.04 ± 0.05 mg/kg). The present study strongly supports the folklore that this valuable plant is a cathartic agent. Further work is required to isolate and validate the bioactive compounds that act as diarrheal agents in Chrozophora tinctoria.  相似文献   
36.
矢车菊和大花金鸡菊的核型研究   总被引:2,自引:0,他引:2  
对矢车菊和大花金鸡菊的染色体进行了研究。结果显示,矢车菊(Centaurea cyanus L.)染色体数目为2n=48,核型公式为K(2n)=4x=48=20m 28sm,相对长度组成为2n=48=4L 24M2 12M1 8S,核型为“2A”;大花金鸡菊(Coreopsis grandifiora Hogg.)的染色体数目为2n=26,核型公式为K(2n)=2X=26=26m,相对长度组成为2n=26=14M2 10M1 2S,核型为“1A”.  相似文献   
37.
ARTP(常压室温等离子体)作为一种新型安全高效的生物诱变育种手段,已成功应用于微生物的育种研究,在植物上的应用刚刚起步.本研究首次采用ARTP处理两色金鸡菊(Coreopsis tinctoria Nutt.)种子,研究其对种子萌发、幼苗生长、花形和品质的影响,以期获得观赏价值大、品质好的诱变品系.结果表明:(1)与对照相比,不同时间(7.50~37.50min)的ARTP辐照提高了两色金鸡菊种子的发芽势和发芽率,辐照22.50min时其发芽势(80.00%)和发芽率(86.70%)达最大;不同时间的ARTP辐照也不同程度地增加了其幼苗的最大冠幅、叶片数量、叶柄长度、叶面积,以22.50min的辐照效果最好.(2)ARTP辐照种子22.50min后,其大部分植株最大花径明显增加、舌状花红褐色区域明显增大,13.33%的植株舌状花瓣数增多(Tm)、6.67%的植株雄蕊瓣化(Ts)、6.67%的植株舌状花管状化(似喇叭状)(Tt);部分植株花朵总黄酮、绿原酸和木犀草苷成分增加,其中Tt植株不仅花形发生变化且活性成分也有所提高.ARTP诱变有望成为两色金鸡菊育种的新途径.  相似文献   
38.
用超声法提取昆仑雪菊中黄酮类化合物,通过大孔树脂对提取液进行纯化,纯化物经聚酰胺层析柱梯度洗脱得到初步分离物,通过颜色反应和紫外光谱扫描进行定性分析。设计正交实验得到超声法提取的最佳工艺条件是65%乙醇、料液比为1∶40、超声时间60 min,此条件下提取3次,总黄酮得率可达132.6 mg/g。通过聚酰胺柱层析法分离出五个组分,初步判断它们属于不同的黄酮类物质。超声法提取总黄酮,提取率较高,聚酰胺树脂对黄酮类化合物的分离效果较好。  相似文献   
39.
用制备的铜掺杂二氧化硅作为吸附剂, 富集雪菊提取液中的木犀草苷, 测量富集有目标组分吸附剂的近红外光谱, 所得光谱经预 处理后, 用偏最小二乘法建立木犀草苷的定量校正模型并进行验证. 结果表明: 当铜掺杂二氧化硅的用量为0.25 g、 常温振荡20 min时, 对木犀草苷吸附率达89.7%; 雪菊提取液中的木犀草苷经吸附剂富集后, 无需脱附可直接检测; 所得近红外光谱经多元散射校正结合一阶导数预处理后, 木犀草苷校正模型的预测质量浓度和参考质量浓度间的相关系数为0.975 0, 交叉验证均方根误差为0.959 8 mg/L, 木犀草苷在1.5~19.5 mg/L的较低质量浓度范围内, 预测集的回收率可达82.6%~111.4%.  相似文献   
40.
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