两面针的化学成分研究

目的：对两面针根的化学成分进行分离和鉴定。方法：采用硅胶柱色谱、Sephadex LH-20柱色谱及重结晶等方法进行成分分离及精制,并利用¹H-NMR,¹³C-NMR,MS等光谱技术鉴定其化学结构。结果：从两面针根乙醇提取液的氯仿部分和正丁醇部分分离得到10个单体化合物,分别鉴定为2,4-二羟基嘧啶(2,4-dihydroxypyrimidine,1),紫丁香酸(syringic acid,2),2,6-二甲氧基对苯醌(2,6-dimethoxy-1,4-benzoquinone,3),对羟基苯甲酸(4-hydroxybenzoic acid,4),对羟基苯甲酸乙酯(ethylparaben,5),顺-3-(2,3,4-三甲氧基苯基)丙烯酸［(Z)-3-(2,3,4-trimethoxyphenyl)acrylic acid,6］,5,6,7-三甲氧基香豆素(5,6,7-trimethoxycoumarin,7),stigmast-9(11)-en-3-ol(8),胡萝卜苷(9),β-谷甾醇(10)。结论：化合物1～9为首次从两面针中分离得到,化合物6是新天然产物。     

巴山花椒根中的生物碱类成分研究

目的 研究巴山花椒Zanthoxylum pashanense根的醋酸乙酯部位的化学成分及其抗炎活性.方法 采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、MCI以及半制备高效液相色谱等多种分离手段进行分离纯化,并结合化合物的理化性质、质谱以及核磁数据进行结构鉴定.采用脂多糖(lipopolysaccharid...     

Biocontrol of Fusarium graminearum,a Causal Agent of Fusarium Head Blight of Wheat,and Deoxynivalenol Accumulation: From In Vitro to In Planta

Crop diseases caused by Fusarium graminearum threaten crop production in both commercial and smallholder farming. F. graminearum produces deoxynivalenol mycotoxin, which is stable during food and feed processing. Therefore, the best way to prevent the sporulation of pathogens is to develop new prevention strategies. Plant-based pesticides, i.e., natural fungicides, have recently gained interest in crop protection as alternatives to synthetic fungicides. Herein we show that treatment with the methanolic extract of medicinal plant Zanthoxylum bungeanum (M20 extract), decreased F. graminearum growth and abrogated DON production. The F. graminearum DNA levels were monitored by a quantitative TaqMan real-time PCR, while DON accumulation was assessed by HPLC quantification. This M20 extract was mainly composed of four flavonoids: quercetin, epicatechin, kaempferol-3-O-rhamnoside, and hyperoside. The in vitro bioassay, which measured the percent inhibition of fungal growth, showed that co-inoculation of four F. graminearum strains with the M20 extract inhibited the fungal growth up to 48.5%. After biocontrol treatments, F. graminearum DNA level was reduced up to 85.5% compared to that of wheat heads, which received F. graminearum mixture only. Moreover, DON production was decreased in wheat heads by 73% after biocontrol treatment; meanwhile in wheat heads inoculated with F. graminearum conidia, an average of 2.263 ± 0.8 mg/kg DON was detected. Overall, this study is a successful case from in vitro research to in planta, giving useful information for wheat protection against F. graminearum responsible for Fusarium Head Blight and DON accumulation in grains. Further studies are needed to study the mechanism by which M20 extract inhibited the DON production and what changes happened to the DON biosynthetic pathway genes.     

花椒属植物中生物活性成分研究近况

综述了近10年来花椒属（ZanthoxylumL)植物中发现的新化合物及其生物活性研究概况。并且简单讨论了化合物结构同生物活性之间的关系。     

调味品花椒的诱变性研究

用小鼠骨髓多染性红细胞（PCE）微核形成和精子畸形测试系统对花椒食用成份的遗传毒性作了进一步检测。花椒食用成份按照模拟用作调味品时的实际烹煮方式提取。实验结果表明由此获得的花椒内提取物各剂量组的小鼠骨髓PCE微核诱发率与阴性对照组1％的微核率间无明显差异（P＞0．5）；精子畸形诱变率与阴性对照组的40．2‰畸形率间亦无显著差异（P≥0．5）。故可认为按习惯使用方式用作调味品时，花椒在体内系统中对真核细胞并无重要遗传毒性。     

两面针果壳的化学成分分析及活性

目的:利用高效液相色谱-线性离子阱/静电场轨道阱高分辨质谱(HPLC-LTQ/Orbitrap-MS)技术对两面针非药用部位果壳中的生物碱类成分进行分析和鉴定,并对其抗氧化活性进行研究,为两面针植物更深入地研究开发提供科学依据。方法:采用HPLC-LTQ/Orbitrap-MS采集数据后,对各色谱峰的质谱图高分辨一级和二级质谱数据进行解析,与文献数据库进行对比,对各色谱峰进行结构推测和确认。采用1,1-二苯基-2-三硝基苯肼(DPPH)清除自由基能力法及2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸(ABTS)自由基清除能力对两面针果壳样品抗氧化活性进行研究。结果:从两面针果壳中共鉴定了25个生物碱类化合物,主要化学成分为异喹啉类生物碱(两面针碱、鹅楸掌碱、木兰箭毒碱),吡咯类生物碱(别隐品碱、氧化苦参碱、氧化槐果碱),喹啉类生物碱(木兰花碱、氯化两面针碱),有机胺类生物碱(γ-山椒素)。DPPH清除自由基能力法及ABTS自由基清除能力对其抗氧化活性进行了研究,结果显示在测定的浓度范围内,抗氧化活性均随着试样浓度的增加而逐渐增强,呈现良好的剂量依赖性。结论:该文对两面针果壳进行了化学成分及活性的研究,研究证明其具有多种生物碱类成分,并具有较好的抗氧化活性,为两面针植物更深入地研究开发提供了参考。     

Chromatographic isolation and estimation of zanthoxylol: an antisickling agent from the roots of Zanthoxylum species

The roots of four species of Zanthoxylum were examined for the presence of zanthoxylol (2-dimethylallyl-4-(3-hydroxy-propyl)phenol) but only Z. zanthoxyloides was found to contain this substance. Purification was effected using Sephadex ionexchange resins; isolation and quantification were performed on reversed-phase HPLC columns. The identity was confirmed by UV, IR, NMR, GC and MS analysis. The zanthoxylol content was calculated as p-hydroxybenzoic acid. The possible chemotaxonomic value of the zanthoxylol content in Zanthoxylum species is speculated.     

Zanthoxylum usambarense (Engl.) Kokwaro (Rutaceae) Extracts Inhibit the Growth of the Breast Cancer Cell Lines MDA‐MB‐231 and MCF‐7, But Not the Brain Tumour Cell Line U251 In Vitro

Zanthoxylum usambarense (Engl.) Kokwaro has traditionally been used for the treatment of malaria, upper respiratory tract infections, cough, rheumatism, tooth decay and sore gums in Kenya and other African countries. Dried ground parts of Z. usambarense were extracted by maceration using methanol (MeOH) at room temperature, extract was dried and reconstituted in 70% aq. MeOH and partitioned against n‐hexane and chloroform (CHCl₃) to obtain MeOH, n‐hexane and CHCl₃ extracts. All extracts were assessed for cytotoxicity against two breast cancer cell lines, MDA‐MB‐231 and MCF‐7, and the brain tumour cell line U251 by the MTT assay. The free‐radical scavenging activity of the extracts was also determined by the 2,2‐diphenyl‐1‐picryhydrazyl (DPPH) assay. In the DPPH assay, the MeOH extract was found to be the most active free‐radical scavenger with a RC₅₀ value of 41.1 × 10^?3 mg/mL. It also displayed significant cytotoxicity against the MCF‐7 cell line (IC₅₀ 42.9 µg/mL) and appeared to have induced cell death through apoptosis. None of the test extracts showed any activity against the U251 cell line at test concentrations. The present findings demonstrated that Z. usambarense could be a potential source for new cytotoxic compounds for possible anticancer drug development. Copyright © 2012 John Wiley & Sons, Ltd.     

两面针提取工艺研究

目的 优选两面针药材的最佳提取工艺.方法 采用正交试验,以乙醇体积分数、乙醇用量、提取次数和提取时间作为优选因素,以出膏率和氯化两面针碱转移率为综合指标,确定合理的醇提取工艺.结果 最佳提取工艺条件是:乙醇体积分数为70%,乙醇用量为8倍,提取4次,每次1.5 h.结论 优化得到的提取工艺稳定可行,为生产提供了实验依据...