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61.
Ji-Fa Zhang Yu Li Feng Gao Lian-Hai Shan 《Journal of Asian natural products research》2019,21(7):716-724
Four new C20-diterpenoid alkaloids, rotundifosines D-G (1–4), along with eight known ones (5–12) were isolated from the whole plant of Aconitum rotundifolium Kar. & Kir. The structures of the compounds were elucidated on the basis of spectroscopic analyses, including HR-ESI-MS and 1D, 2D NMR. Rotundifosine F (3) is a rare C20-diterpenoid alkaloid with quaternary ammonium salt. Alkaloids 1–4, 5, 6, 9, and 12 were evaluated for cytotoxicity against MCF-7, HCT-116 and HepG2 human cancer cell lines. 相似文献
62.
益母草为唇彤科植物益母草的全草,是常用的中药。现代研究表明,益母草具有广泛的医药用途和应用前景。通过查阅近几年对其化学作用以及药理作用研究成果的文献,对其化学成分及药理作用进行分析、归纳、总结,完成本篇综述,目的是希望能为益母草的进一步开发利用提供一定的参考。 相似文献
63.
Dynamic detection of non‐protein‐bound strychnine and brucine in rabbit muscle and synovial fluid after topical application of total Strychnos alkaloid patches
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Semen Strychni, a known toxic drug in Chinese pharmacopoeia, is notable for its therapeutic effects on local muscle and joint pain. However, oral administration can be risky. Topically administered drugs accumulate in the topical muscles and knee joints without any major increase in plasma levels; only non‐protein‐bound drugs in the biological fluids of target tissues are effective for therapeutic effects. A sensitive and rapid ultra performance liquid chromatography ‐ mass spectrometry (UPLC‐MS) method coupled with a microdialysis technique was developed to determine the non‐protein‐bound strychnine (Str) and brucine (Bru) in rabbit muscle and synovial fluid microdialysate. The UPLC separation was carried out using a 1.7μm BEH C18 column (50 mm × 2.1 mm) with a mobile phase consisting of methanol: water (29.5:70.5, v/v) with 0.1% formic acid and 20 mM ammonium acetate in water. The method was validated at concentrations ranging from 0.58 ng/ml to 467.20 ng/ml for Str and from 0.42 ng/ml to 422.40 ng/ml for Bru. Intra‐day and inter‐day accuracy ranged from 99.1% to 103.2% for Str and from 95.8% to 108.8% for Bru with intra‐day and inter‐day precision within 9.7%. The proposed method was successfully applied to determine non‐protein‐bound Str and Bru, and the analysates concentration remained stable in rabbit muscle and synovial fluid after topical application of total Strychnos alkaloid patches, which indicated that total Strychnos alkaloid patches could substitute for the traditional oral administration of Semen Strychni. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
64.
Ergot alkaloids are nitrogen-containing natural products belonging to indole alkaloids. The best known producers are fungi of the phylum Ascomycota, e.g., Claviceps, Epichloë, Penicillium and Aspergillus species. According to their structures, ergot alkaloids can be divided into three groups: clavines, lysergic acid amides and peptides (ergopeptines). All of them share the first biosynthetic steps, which lead to the formation of the tetracyclic ergoline ring system (except the simplest, tricyclic compound: chanoclavine). Different modifications on the ergoline ring by specific enzymes result in an abundance of bioactive natural products, which are used as pharmaceutical drugs or precursors thereof. From the 1950s through to recent years, most of the biosynthetic pathways have been elucidated. Gene clusters from several ergot alkaloid producers have been identified by genome mining and the functions of many of those genes have been demonstrated by knock-out experiments or biochemical investigations of the overproduced enzymes. 相似文献
65.
目的 探究滇黄精Polygonatum kingianum传统炮制过程化学成分变化规律。方法 按照九蒸九晒法进行滇黄精炮制,应用分光光度法和HPLC测定炮制过程中总多糖、总皂苷、总多酚、总黄酮和游离氨基酸的含量。应用UPLC-MS/MS的广泛靶向代谢组学技术检测原料和炮制后的代谢产物。结果 随着炮制次数的增加,颜色逐渐加深,第3次蒸制后为深褐色,第4次至炮制结束缓慢转变为黑色。滇黄精原料具有麻味,第4蒸之后麻味消失,变为酸甜味。炮制过程中多糖和16种游离氨基酸含量降低,总皂苷、总黄酮和总多酚含量增加。广泛靶向代谢组学共检测到419个代谢物,氨基酸及其衍生物66个,脂质65个,酚酸类52个,黄酮类51个,有机酸42个,生物碱41个,核苷酸及其衍生物32个,甾体9个,木脂素和香豆素7个,异黄酮1个,萜类3个,其他类物质50个。结论 系统阐述了滇黄精九蒸九晒炮制过程中化学成分的变化,九蒸九晒对滇黄精中的化学成分影响较大,随着炮制时间的增加,氨基酸及其衍生物和生物碱类化合物的相对丰度降低,有机酸和酚酸类相对丰度增加等。该研究可为炮制滇黄精有效成分的筛选与质量评价提供参考,同时差异性成分的发现为研究滇黄精生熟饮片中差异性物质的分析提供新思路,对滇黄精的扩大开发利用有重要意义。 相似文献
66.
夹竹桃科(Apocynaceae)狗牙花属(Ervatamia Stapf)植物中的化学成分以及其生物活性一直是研究热点。其在全世界有约120种,主要分布在印度、中国西南地区,东南亚、大洋洲、北美洲、南美洲部分地区以及各海岛;在我国主要有15种和5变种,主要分布在华南地区及西南地区和台湾。我国傣族将云南狗牙花茎用于治疗产后体虚、头晕目眩、恶露淋漓等症状。据《中国植物志》中记载,产于亚洲热带与亚热带地区的单瓣狗牙花,其叶有降低血压功效,常用于治眼病、疮疥、乳疮、咬伤等;根可治头痛和骨折等。生物碱是狗牙花属植物中的主要化学成分,具有新颖的化学结构。现代药理学研究发现,狗牙花属植物中生物碱类成分具有抗肿瘤和抗乙酰胆碱脂酶等生物活性,其中抗肿瘤活性最为显著。因此狗牙花属植物具有很好的开发价值。但是,科研人员对狗牙花属植物生物碱类成分的研究仅限于发现与生物活性的测定,临床功效的研究较少。笔者结合近20年来的国内外文献对该属植物中149个生物碱进行总结,为进一步研究具有显著活性的生物碱类化学成分,合理充分利用狗牙花属植物的药用资源提供有价值的参考。 相似文献
67.
The aim of this review is to collect together the results of the numerous studies over the last two decades on the pharmacological properties of palmatine published in scientific databases like Scopus and PubMed, which are scattered across different publications. Palmatine, an isoquinoline alkaloid from the class of protoberberines, is a yellow compound present in the extracts from different representatives of Berberidaceae, Papaveraceae, Ranunculaceae, and Menispermaceae. It has been extensively used in traditional medicine of Asia in the treatment of jaundice, liver‐related diseases, hypertension, inflammation, and dysentery. New findings describe its possible applications in the treatment of civilization diseases like central nervous system‐related problems. This review intends to let this alkaloid come out from the shade of a more frequently described alkaloid: berberine. The toxicity, pharmacokinetics, and biological activities of this protoberberine alkaloid will be developed in this work. 相似文献
68.
Pratik Shriwas Xiaozhuo Chen A. Douglas Kinghorn Yulin Ren 《Phytotherapy research : PTR》2020,34(5):1027-1040
Glucose, a key nutrient utilized by human cells to provide cellular energy and a carbon source for biomass synthesis, is internalized in cells via glucose transporters that regulate glucose homeostasis throughout the human body. Glucose transporters have been used as important targets for the discovery of new drugs to treat cancer, diabetes, and heart disease, owing to their abnormal expression during these disease conditions. Thus far, several glucose transport inhibitors have been used in clinical trials, and increasing numbers of natural products have been characterized as potential anticancer agents targeting glucose transport. The present review focuses on natural product glucose transport inhibitors of plant origin, including alkaloids, flavonoids and other phenolic compounds, and isoprenoids, with their potential antitumor properties also discussed. 相似文献
69.
Bahare Salehi Dmitry A. Konovalov Pascaline Fru Petrina Kapewangolo Gregorio Peron Mileski S. Ksenija Susana M. Cardoso Olivia R. Pereira Manisha Nigam Silvana Nicola Giuseppe Pignata Simona Rapposelli Simona Sestito Nanjangud V. Anil Kumar María de la Luz Cdiz‐Gurrea Antonio Segura‐Carretero Abhay P. Mishra Mehdi Sharifi‐Rad William C. Cho Yasaman Taheri William N. Setzer Javad Sharifi‐Rad 《Phytotherapy research : PTR》2020,34(9):2140-2158
The family Arecaceae includes 181 genera and 2,600 species with a high diversity in physical characteristics. Areca plants, commonly palms, which are able to grow in nearly every type of habitat, prefer tropical and subtropical climates. The most studied species Areca catechu L. contains phytochemicals as phenolics and alkaloids with biological properties. The phenolics are mainly distributed in roots followed by fresh unripe fruits, leaves, spikes, and veins, while the contents of alkaloids are in the order of roots, fresh unripe fruits, spikes, leaves, and veins. This species has been reputed to provide health effects on the cardiovascular, respiratory, nervous, metabolic, gastrointestinal, and reproductive systems. However, in many developing countries, quid from this species has been associated with side effects, which include the destruction of the teeth, impairment of oral hygiene, bronchial asthma, or oral cancer. Despite these side effects, which are also mentioned in this work, the present review collects the main results of biological properties of the phytochemicals in A. catechu. This study emphasizes the in vitro and in vivo antioxidant, antimicrobial, anticancer, and clinical effectiveness in humans. In this sense, A. catechu have demonstrated effectiveness in several reports through in vitro and in vivo experiments on disorders such as antimicrobial, antioxidant, or anticancer. Moreover, our findings demonstrate that this species presents clinical effectiveness on neurological disorders. Hence, A. catechu extracts could be used as a bioactive ingredient for functional food, nutraceuticals, or cosmeceuticals. However, further studies, especially extensive and comprehensive clinical trials, are recommended for the use of Areca in the treatment of diseases. 相似文献
70.
目的研究海南地不容(Stephania hainanensis H.S.Lo et Y.Tsoong)生物碱对人肝癌细胞Hep G-2、乳腺癌细胞MCF-7、胃癌细胞SGC-7901增殖的影响,筛选出有效的抗肿瘤化合物以及其敏感细胞株;分析其生物碱的构效关系。方法采用MTT法检测不同浓度的海南地不容生物碱对人肝癌细胞Hep G-2、乳腺癌细胞MCF-7、胃癌细胞SGC-7901增殖的抑制率;通过查阅国内外相关文献,分析海南地不容生物碱抗肿瘤活性的基本构效关系。结果MTT结果显示荷包牡丹碱、氧化克班宁、去甲荷包牡丹碱和克班宁对人肝癌Hep G-2、乳腺癌MCF-7和胃癌SGC-7901细胞的增值分别具有不同程度的剂量依赖性的抑制作用,各给药组分吸光度值与空白对照组比具有显著性差异(P<0.01),与阳性对照比较无明显统计学差异(P>0.05);海南地不容生物碱结构中的1,2-亚甲二氧基、N-亚甲基等取代基以及其化学结构的平面性对其抗肿瘤活性有重要影响。结论海南地不容中具有明显抗肿瘤作用的生物碱为荷包牡丹碱、氧化克班宁、去甲荷包牡丹碱和克班宁,其敏感细胞株均为乳腺癌细胞MCF-7;通过分析海南地不容生物碱的结构和抗肿瘤活性的关系,初步明确了其抗肿瘤活性可能与其结构易于抑制DNA拓扑异构酶和诱导细胞凋亡有关。 相似文献