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81.
The purpose of the research was to investigate the multiple response optimizations for the extraction of protopine and allocryptopine from the stems of Macleaya cordata (Willd) R. Br. by using microwave‐assisted extraction (MAE). A three‐level, three‐factor Box–Behnken design of response surface methodology was used to develop response model, and desirability function was employed to optimize the effects of main extraction parameters. Three variables, ethanol concentration (20–80%, v/v), extraction temperature (30–70°C) and solvent/solid ratio (10:1 to 30:1, mL/g), were investigated in this study. The results showed that the optimum parameters of MAE were ethanol concentration of 45.2 % (v/v), extraction temperature of 54.7°C and solvent/solid ratio of 20.4:1 (mL/g). Under these conditions, the extraction yields of protopine and allocryptopine were 89.4 and 102.0%, respectively, and the extracta sicca yield was 12.5%. The combination use of response surface methodology, Box‐Behnken design and the appropriate desirability function could provide an insight into a lab‐scale MAE process, and help to develop procedures for commercial production of active ingredients from medical plants.  相似文献   
82.
The germacranolide 11,13-dihydroridentin, for which the previously unknown S-configuration of the asymmetric center on C-11 was established, was isolated for the first time from Artemisia pontica L. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 341–342, July–August, 2005.  相似文献   
83.
Macleaya cordata (Willd) R. Br. is a medicinal plant. The most important bioactive compounds of M. cordata are alkaloids that have many biological activities including antifungal, anti‐inflammatory, and antitumor. In this study, an ionic‐liquid‐modified high‐speed counter‐current chromatography method was established to obtain alkaloids from the fruits of M. cordata. The conditions of ionic‐liquid‐modified high‐speed counter‐current chromatography, including solvent systems, the content of ionic liquid (1‐butyl‐3‐methylimidazolium tetrafluoroborate [C4mim][BF4]), and the posttreatment of the ionic liquid, were investigated. Five alkaloids protopine, allocryptopine, sanguinarine, 8‐O‐demethylchelerythrine, and chelerythrine were separated from the extract of the fruits using a high speed counter‐current chromatography with two‐phase solvent system composed of dichloromethane/methanol/0.3 mol/L hydrochloric acid aqueous solution/[C4mim][BF4] (4:2:2:0.015, v/v). Their purities were 96.33, 95.56, 97.94, 96.22, and 97.90%, respectively. The results indicated that a small amount of ionic liquids as modifier of the two‐phase solvent system could shorten the separation time and improve the separation efficiency of the alkaloids from the fruits. The ionic‐liquid‐modified high‐speed counter‐current chromatography would provide a feasible way for highly effective separation of alkaloids from natural products.  相似文献   
84.
火焰原子吸收法测定栽培柴胡中六种金属元素含量的研究   总被引:21,自引:4,他引:17  
采用浓硝酸-高氯酸(V:V=4:1)常压微沸条件下消解柴胡样品,应用火焰原子吸收法测定栽培柴胡中的金属元素Ca,Mg,Fe,Cu,Zn,Pb的含量.研究了测定不同元素的仪器最佳工作条件及溶液介质对测定结果的影响,并做了方法的准确性和精密度考察.结果表明,栽培柴胡中Ca,Mg,Fe,Cu,Zn的含量分别为5 588.9,1 790.5,869.3,78.4,44.3μg·g-1,Pb未检出.方法的加标回收率为99.57%~102.10%,相对标准偏差(n=9)为0.18%~2.26%.测定方法简单易行,方便快捷,结果可靠.  相似文献   
85.
Coeloglossum viride (L.) Hartm. var. bracteatum (Willd.) Richter is a plant of the Orchidaceae family, distributed in the Xinjiang, Inner Mongolia, Gansu and Qinghai provinces of China1. Its dried rhizomes have been used as a tonic in chinese folk medicine2. No chemical constituent is reported from this plant. The present paper deals with the isolation and structural elucidation of two new isobutyltartrate monoesters, named coelovirin A 1 and B 2. The ethanolic extract of the air-drie…  相似文献   
86.
矿物元素的种类和含量是中药材质量评价的重要指标,与中药材的生长发育、药用物质的形成以及临床疗效的发挥密切相关。中药材矿物元素的分布因产地间气候、土壤、水文等生态因子不同而凸显的质量特征和作用规律是值得探索的问题。以4个省份5个主产区的75份艾叶样品为实验材料,利用电感耦合等离子体质谱法(ICP-MS)和电感耦合等离子体原子发射光谱法(ICP-AES)法测定Ca,K,Mg,Na,Fe,Sn,Be,As,Al,V,Sc,Cr,Mn,Co,Bi,Ga,Ni,La,Mo,Ag,Hg,Cu,Nb,Zn,Ge,Se,Tl,Cd,Sb,Ba,Y,Ti,Pb,Zr和Sr等元素的含量,并采用方差分析、主成分分析、因子分析等计量学方法进行统计与评价。结果表明:(1)所建立的分析方法线性关系良好,加标回收率高,具有较高的准确度和精密度。(2)35种矿物元素中有33种矿物元素的含量在不同产地间存在显著差异(p<0.05)。(3)以35种矿物元素的含量为变量,共提取7个主成分,累计方差贡献率达82.75%,主成分得分图显示不同产地艾叶样品的分布相对集中,具备分类和评价的条件。(4)选择前7个因子对艾叶进行综合评价,评价函数为F=0.449 1F1+0.118 0F2+0.097 2F3+0.055 5F4+0.042 5F5+0.034 5F6+0.030 7F7,通过计算总因子得分值F可知,河北安国的祁艾与湖北蕲春的蕲艾排在前列,表明从矿物元素角度考虑,以上2个产地的艾叶品质较好。研究建立了不同产地艾叶中矿物元素的准确高效分析方法及评价体系,为艾叶的质量控制及标准建立提供科学依据,也为其他药材的等同性研究提有益参考。  相似文献   
87.
A green palladium‐based catalyst supported on Artemisia abrotanum extract‐modified graphene oxide (Pd NPs/RGO‐A. abrotanum) hybrid material has been used as a recoverable and heterogeneous nanocatalyst for the catalytic reduction of various dyes, including methylene blue, methyl orange and rhodamine B, in the presence of NaBH4 as reducing agent in aqueous medium at room temperature. With the help of UV–visible spectroscopy, the catalytic reactions were investigated. According to the results, these reactions followed the pseudo‐first‐order rate equation.  相似文献   
88.
Artemisia annua is a promising and potent antimalarial herbal drug. This activity has been ascribed to its component artemisinin, a sesquiterpene lactone. The ability to determine artemisinin and its known analogs in plant extracts is an especially difficult task because the compounds are present in low concentrations, are thermolabile, and lack ultraviolet or fluorescent chromophores. We report herein a facile and rapid 1-D 1H, 1-D total correlation spectroscopy, 2-D 1H–13C heteronuclear single quantum coherence, and 1H–13C heteronuclear multiple bond correlation nuclear magnetic resonance techniques for the simultaneous identification and quantification of artemisinin and five of its analogs along with five flavonoids, an aromatic ketone, and camphor (in total, 13 compounds) in crude diethyl ether A. annua extract without the need of laborious isolation of the individual analytes. The above method was validated in terms of precision, linearity, and limit of detection. The analytical results were found to be in excellent agreement with those obtained with the use of the time consuming high-performance liquid chromatography with diode-array detection and liquid chromatography with tandem mass spectrometry for the compounds that standards were available.  相似文献   
89.
联合国政府间气候变化专门委员会(IPCC,2007)指出,伴随着全球变暖,氮沉降的现象也日益加剧。通过野外控制实验,使用红外辐射器增温(+2℃)和人工添加NH4NO3(+10g N·m-2.a-1),模拟未来气候变暖与氮沉降状态,设计对照(CK)、增温(IR)、施氮(N)、增温施氮(IRN)四种处理,结合ICP-AES法研究气候变暖与氮沉降对传统蒙药材——阿给12种必需元素在生殖(营养)部位中分配的影响。结果表明:增温与施氮处理改变阿给对必需元素的吸收与分配。增温条件下12种元素含量虽有波动,但基本上呈现出负效应大于正效应的趋势。施氮处理明显改善磷、锰的吸收。同时,增温与施氮处理之间的交互作用不显著。生殖枝与营养枝之间,只有氮、钾、钙、镁四种元素表现出显著性差异。  相似文献   
90.
Cirsium setosum (Willd.) MB. has been reported to exert significant anti‐hemorrhagic, anti‐inflammation, antimicrobial, sedative and detoxicating efficacy. It has been widely used to treat gastrointestinal bleeding, uterine bleeding, infectious hepatitis and cardiovascular disease in China. Recent studies have shown that flavonoids are the main active components in C. setosum. Nevertheless, to the best of our knowledge, there is no report concerning the simultaneous determinations and pharmacokinetics of constituents in C. setosum flavonoids in rat plasma. In this study, a rapid, sensitive and selective triple quadrupole liquid chromatography–mass spectrometry method was developed to determine eight analytes from the flavonoids of C. setosum in rat plasma. In addition, the pharmacokinetic study of the eight analytes in rats after oral administration of C. setosum flavonoids was successfully completed through this method. According to the pharmacokinetic parameters of the eight analytes, rutin, naringin, quercetin, acacetin, wogonin were the long‐acting components of the C. setosum flavonoids, with long elimination time and high bioavailability. Of note, the method developed in this study fills a blank in pharmacokinetic studies of C. setosum flavonoids. Our findings provide valuable views on the understanding of the absorption mechanism of C. setosum flavonoids and their clinical efficacy.  相似文献   
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