Potential inhibitors of platelet aggregation from plant sources, III

3,4-Dihydroxybenzoic acid (DBA) was isolated from Acanthopanax senticosus as an antiplatelet aggregatory substance. This paper also reports the results of the investigations on the structural activity relationships among the various dihydroxybenzoic acid derivatives against rat platelet aggregations induced by ADP (adenosine 5'-diphosphate), AA (arachidonic acid), or collagen.     

Modified smear method for screening potential inhibitors of platelet aggregation from plant sources

The smear method developed by Velaskar and Chitre was modified to allow the massive screening of plant extracts and/or fractions for platelet antiaggregating activity. Aspirin and papaverine, known inhibitors of platelet aggregation, were tested by the modified method and showed comparable results with previously reported data. Fifty-four fractions prepared from eighteen plant species were screened for their inhibitory effects on adenosine 5'-diphosphate, arachidonic acid, or collagen-induced rat platelet aggregation. The results suggest that plants could be a potential source of inhibitors of platelet aggregation.     

决明种子硬实及萌发特性研究

目的通过对决明种子硬实和萌发特性的研究,找到打破种子硬实、提高种子萌发率的适宜条件。方法观察种子外部形态,对决明种子长宽、千粒质量、净度、硬实率、含水量和吸水率进行测定,通过研磨、预先冷冻和热水处理,找到破除种子硬实的方法,考察不同温度、不同质量浓度化学物质对种子萌发率的影响。结果决明种子含水量为10.43%,未经处理的种子吸水率为45.82%,经过研磨处理和浓硫酸处理的种子吸水率分别为154.2%、159.7%。经过98%浓硫酸处理20 min后的种子发芽率为99.8%,变温下(25℃1、4 h/15℃1、0 h)种子萌发率为98.7%,200 mg/L GA3和200 mg/L PEG处理后的萌发率分别为100%和98.9%,较高质量浓度的NNA和6-BA对种子萌发具有明显的抑制效应。结论种皮硬实是限制种子萌发的主要因素,98%的浓硫酸浸泡20 min可以较好地打破决明种子硬实,200 mg/L GA3和200 mg/L PEG能在短时间内显著提高种子的萌发率,最佳萌发温度为25℃,14 h/15℃,10 h。     

决明子中总蒽醌苷元的大孔吸附树脂纯化工艺的研究

目的探索决明子蒽醌苷元的大孔吸附树脂纯化工艺。方法以决明子总蒽醌苷元质量分数和收率为主要考察指标,比较了乙醚和氯仿对蒽醌苷元提取的专属性,考察了大孔吸附树脂S-8、AB-8、X-5、NKA-12、D4020、D-101对决明子蒽醌苷元的吸附和解吸附特性以及纯化能力。结果决明子药粉采用氯仿浸提,上S-8型大孔树脂柱,水洗至中性,乙醇-5%NaOH(4∶1)洗脱,醇碱洗脱液浓缩、酸化处理得到质量分数为42.62%的蒽醌苷元。结论建立了一种蒽醌苷元的纯化工艺,为决明子中蒽醌苷元类成分的工业化生产提供依据。     

Four new compounds from the seeds of Cassia fistula

Four new compounds, 5-(2-hydroxyphenoxymethyl)furfural (1), (2'S)-7-hydroxy-5- hydroxymethyl-2-(2'-hydroxypropyl)chromone (2), benzyl 2-hydroxy-3,6-dimethoxybenzoate (3), and benzyl 2beta-O-D-glucopyranosyl-3,6-dimethoxybenzoate (4), together with four known compounds, 5-hydroxymethylfurfural, (2'S)-7-hydroxy-2-(2'-hydroxypropyl)-5-methylchromone, and two oxyanthraquinones, chrysophanol and chrysophanein, were isolated and identified from the seeds of Cassia fistula. The structures of 1-4 were determined on the basis of spectral data explanation, and the synthesis of compound 1 was carried out.     

HPLC测定决明子中决明子苷A,B含量

 目的:建立决明子中降血脂有效成分决明子苷A,B(以下简称苷A,B)的HPLC定量测定方法。方法:决明子药材经氯仿脱脂后再由甲醇提取,甲醇提取液经释释后直接进样分析;在μ-Bondapak C₁₈柱上,以乙腈-水-四氢呋喃-冰醋酸(20∶76.5∶3.0∶0.5)为流动相,流速为1ml·min^-1,检测波长为278nm,测定了样品中苷A、B含量,并采用光谱法和色谱法对A、B峰的色谱纯度进行了鉴定。结果:苷A、B的保留时间分别为12.13min和13.27min,经鉴定苷A、B峰均为单一物质色谱峰:苷A、B的标准曲线分别在0.25～1.25μg(r=0.9999)和0.125μg～0.625μg(r=0.9999)之间有较好线性关系,苷A、B的加样回收率分别为(96.83±3.53)%和(97.78±2.16)%。结论:本法专属性强,可用于决明子中决明子苷A、B的含量测定。     

决明子炒制前后指纹图谱比较研究

目的:研究建立决明子不同饮片的HPLC指纹图谱鉴别方法,比较生、炒决明子化学成分的差别.方法:采用RP-HPLC,流动相乙腈-0.1%磷酸水溶液梯度洗脱,研究生、炒决明子饮片指纹图谱的区别,作相似度分析,并对其主要色谱峰进行指认.结果:生、炒决明子饮片的HPLC指纹图谱有明显差异,并指认了12个主要色谱峰.结论:采用HPLC图谱比较法可作为生、炒决明子饮片的一项质控鉴别指标.     

决明子挥发油成分的GC-MS分析△

目的:应用GC-MS分析决明子挥发油的化学成分,比较水蒸气蒸馏法和超临界CO2萃取方法所萃取决明子挥发油的化学成分.方法:分别采用水蒸气法和超临界CO2萃取法提取决明子中的挥发性成分,气谱-质谱联用(GC-MS)测定和分析其化学组分.结果:超临界CO2萃取法得率高于水蒸气法得率,其决明子挥发油在保持较高的亚油酸和油酸含量同时含有更多其他成分.结论:超临界CO2萃取法适于提取决明子挥发油.     

决明子炒制前后2类成分的含量比较研究

目的:建立HPLC测定生、炒决明子中2类成分的方法,以期了解生、炒决明子中成分的含量差异.方法:使用Alltima C_(18)(4.6 mm × 150 mm,5μm),柱温30℃;流速1.0 mL·min~(-1).色谱条件I乙腈-四氢呋喃-0.1%磷酸水溶液(17:3:80),检测波长278 nm;色谱条件Ⅱ甲醇-0.1%磷酸水溶液(79:21),检测波长254 nm,分别测定2类成分的含量.通过结果分析比较2类成分在生、炒决明子中的差别.结果:2类成分5个化合物在一定范围内均呈现良好的线性关系(r>0.999 7);精密度可靠RSD<1.6%;重复性好RSD<1.8%;样品在24 h内基本稳定.2类成分5个化合物在生、炒决明子中的含量均有差异.结论:本研究为决明子饮片的质量评价提供了较为全面的参考.     

葡萄籽原花青素对血小板聚集与实验性血栓形成的影响

目的 观察葡萄籽原花青素对血小板聚集和实验性血栓形成的影响.方法 ①大鼠血栓形成实验按随机数字表法分为5组:生理盐水(对照)组、阿司匹林(ASP)组(60 mg/kg)及原花青素100 mg/kg、200 mg/kg、400 mg/kg组,每组各10只.②小鼠血栓形成实验按随机数字表法分为5组,生理盐水(对照)组、阿司匹林组(84mg/kg)及原花青素140mg/kg、280mg/kg、560mg/kg组,各10只.实验动物采用二磷酸腺苷(ADP)、胶原(COL)、花生四烯酸(AA)灌胃,诱导大鼠血小板聚集;采用大鼠动-静脉旁路丝线上血检形成和胶原蛋白-肾上腺素诱发小鼠体内血栓形成,两种方法均以阿司匹林为阳性对照.结果 ①原花肯素高、中、低剂量组均可抑制大鼠颈总动脉-颈外静脉血流旁路血栓的湿重:高、中剂量对血栓干重有明显作用,但不及阿司匹林.②原花青素高剂量组可对抗胶原蛋白-肾上腺素混合诱导剂引起的血栓形成,减少动物死亡数.⑨原花青素中、高剂量组均可抑制ADP、COL、AA诱导的大鼠血小板聚集及两种方法引起的实验性血栓形成.结论 原花青素具有抑制实验性血栓形成和抗血小板聚集作用.     

Blepharocalyxins C--E, three new dimeric diarylheptanoids, and related compounds from the seeds of Alpinia blepharocalyx

Three novel diarylheptanoids, blepharocalyxins C--E (5--7), together with four new (1--4) and one known (8) diarylheptanoids bearing a tetrahydropyran ring were isolated from the residual fraction of an EtOH extract of the seeds of Alpinia blepharocalyx. The structures and the stereochemistry at the chiral centers of the new diarylheptanoids were elucidated by spectroscopic techniques including 2D NMR spectroscopy. Blepharocalyxins C--E (5--7) have a novel carbon framework and are dimeric diarylheptanoids consisting of two diarylheptanoid units. Blepharocalyxin D (6) showed potent antiproliferative activity against murine colon 26-L5 carcinoma cells (ED(50), 3.61 microM), while against human HT-1080 fibrosarcoma cells, blepharocalyxin E (7) showed potent activity (ED(50), 9.02 microM).     

望江南蒽醌类成分的提取及抗肝癌活性研究

目的:研究望江南蒽醌类成分的提取工艺及抗肝癌活性。方法:以植物望江南为研究对象,设计了望江南蒽醌类成分的提取工艺,并采用CCK-8法观察了望江南蒽醌类各化合物体外对肝癌细胞(HepG2)的可能作用。Hoechst 33258染色实验观察了胡萝卜苷、芦荟大黄素、大黄酚、大黄酸对Hep G2细胞凋亡的影响。结果:本文的提取工艺对望江南种子进行提取,结果分离并鉴定了7个化合物,分别为:β-谷甾醇(1)、胡萝卜苷(2)、大黄素甲醚吡喃葡糖苷(3)、大黄素甲醚(4)、芦荟大黄素(5)、大黄酚(6)、大黄酸(7)。其中,化合物1、2、3、5、7为首次从望江南中分离得到。胡萝卜苷、大黄素甲醚、芦荟大黄素、大黄酚、大黄酸等望江南中蒽醌类化合物均对肝癌Hep G2的具有抑制作用。不同望江南蒽醌类化合物对Hep G2细胞的抑制率是不同的。大黄酸药物干预组HepG2细胞凋亡比较明显,部分细胞核浓染呈亮蓝色,出现凋亡小体。结论:望江南可能具有良好的体外抗肝癌作用,作为天然抗肿瘤植物,具有很好的发展前景和开发利用价值。     

决明子水提液对高血压小鼠血压血脂及肾脏结构的影响

目的: 检测决明子水提液对冷激诱导的高血压小鼠血压、血脂及肾脏结构的影响。 方法: 制备决明子水提液备用。实验小鼠分为正常对照组、冷激对照组、冷激决明子饲喂组(5,10,20 mg·kg^-1.BW),对照组相应给予等量生理盐水,连续饲喂18 d。检测各组小鼠血压、血脂含量,切片观察肾脏结构。 结果: 冷激对照组血压显著高于正常对照组( P <0.01),决明子水提液饲喂组小鼠的收缩压、舒张压、平均动脉压与正常对照组相比,差异不显著( P >0.05)。冷激对照组TG含量显著高于正常对照组( P<0.01 ),而冷激饲喂组TG含量明显降低( P<0.05 );冷激饲喂(10 mg·kg^-1,20 mg·kg^-1)组TC含量降低( P<0.05 );冷激饲喂(10 mg·kg^-1)组LDL与HDL含量均降低,其他饲喂组与冷激对照组相比含量虽有降低但无统计学意义。冷激对照组肾小管管壁水肿,内腔极度缩小,肾小球明显胀大,肾小囊腔显著变窄,决明子饲喂组肾小管水肿基本消失,内腔明显增大,肾小球、肾小囊结构趋于正常。 结论: 决明子水提液具有降血压、降血脂、改善病变肾脏结构的作用。     

Potential antipsoriatic agents: lapacho compounds as potent inhibitors of HaCaT cell growth.

A number of lapacho compounds, representing the most common constituents of the inner bark of Tabebuia impetiginosa, together with some synthetic analogues, were evaluated in vitro against the growth of the human keratinocyte cell line HaCaT. With an IC(50) value of 0.7 microM, beta-lapachone (4) displayed activity comparable to that of the antipsoriatic drug anthralin. 2-Acetyl-8-hydroxynaphtho[2,3-b]furan-4,9-dione (7), which was prepared in a four-step synthesis from 2,8-dihydroxy-1, 4-naphthoquinone, was the most potent inhibitor among the known lapacho-derived compounds and inhibited cell growth with an IC(50) value of 0.35 microM. Furthermore, other active constituents of lapacho inhibited keratinocyte growth, with IC(50) values in the range of 0.5-3.0 microM. However, as already observed with anthralin, treatment of HaCaT cells with these potent lapacho compounds also caused remarkable damage to the plasma membrane. This was documented by leakage of lactate dehydrogenase into the culture medium, which significantly exceeded that of the vehicle control. Because of their potent activity against the growth of human keratinocytes, some lapacho-derived compounds appear to be promising as effective antipsoriatic agents.     

Nutmeg oil: identification and quantitation of its most active constituents as inhibitors of platelet aggregation

Three distilled or commercially available nutmeg oils were analysed and their chemical composition compared with their capacity to inhibit platelet aggregation in vitro. It could be clearly shown that eugenol and isoeugenol play the major role in the detected activity of nutmeg. Medicinally, it appears that nutmeg oil and nutmeg powder can be replaced by eugenol and/or isoeugenol.     

红花提取物抗血小板聚集及抗血栓作用的观察

我 们的实验观察了红花提取物对体外ADP诱导的血小板聚集和体内血栓 形成的作用。结果发现红花提取物能明显抑制ADP诱导的兔血小板聚集,显抑制大鼠实验性血栓形成并延长其凝血时间和凝血酶时间。     

Cactus alkaloids. XXXVI. Mescaline and related compounds from Trichocereus peruvianus

Agurell has previously detected (tlc, glc-ms) tyramine, 3-methoxytyramine, and two unknown alkaloids in the Peruvian cactus, Trichocereus peruvianus Br. and R. The presence of mescaline in other similar Trichocereus species prompted us to reinvestigate this species, which is commercially available in the United States. The nonphenolic alkaloid extracts yielded an abundance of crystalline mescaline hydrochloride (0.82% yield) and a trace of 3,4-dimethoxyphenethylamine (tlc-ms). Crystalline tyramine hydrochloride, 3-methoxytyramine hydrochloride, and 3,5 dimethoxy-4-hydroxphenethylamine hydrochloride were isolated from the phenolic alkaloid extracts; the last compound has not been previously crystallized from nature, although it is the immediate biosynthetic precursor of mescaline. Crystalline 2-chloromescaline hydrochloride was isolated drom the nonphenolic extracts; but, as determined by mass-analyzed ion kinetic energy spectrometry, this new compound is an extraction artifact. Both 2-chloromescaline and 2.6-dichloromescaline hydrochlorides were prepared synthetically from mescaline. This cactus species has a mescaline content equal or superior to peyote and should be legally controlled as an item of drug abuse.     

Antibacterial and antifungal activity of Cassia fistula L.: an ethnomedicinal plant

Hexane, chloroform, ethyl acetate, methanol and water extracts from the flower of Cassia fistula (an ethnomedicinal plant) were tested against bacteria and fungi. All the extracts exhibited antibacterial activity against Gram-positive organisms with minimum inhibitory concentrations (MIC) between 0.078 and 2.5 mg/ml. Among the Gram-negative bacteria, only Pseudomonas aeruginosa was susceptible to the extracts. Ethyl acetate crude extract was fractionated using chromatographic techniques. A crystal was isolated, which was confirmed as 4-hydroxy benzoic acid hydrate using X-ray crystallography. It exhibited antifungal activity against Trichophyton mentagrophytes (MIC 0.5 mg/ml) and Epidermophyton floccosum (MIC 0.5 mg/ml).     

Lipoxygenase inhibitors from natural plant sources. Part 2: medicinal plants with inhibitory activity on arachidonate 12-lipoxygenase, 15-lipoxygenase and leukotriene receptor antagonists

The metabolism of arachidonic acid can be catalysed by either one of two enzyme families: the cyclooxygenases or the lipoxygenases. The lipoxygenase enzymes are classed into several subcategories including 5-, 12- and 15-lipoxygenases. The 5-lipoxygenase pathway has been the major focus of study due to the pronounced pro-inflammatory role of leukotrienes and the approval of 5-lipoxygenase inhibitors and leukotriene receptor antagonists for the clinical treatment of asthma. Although less well characterized, the 12-lipoxygenase as well as the 15-lipoxygenase pathway may also play an important role in the progression of human diseases such as cancer, psoriasis and atherosclerosis. The present review article summarizes the findings from an extensive literature search on plants that have been assessed for 12- and 15-lipoxygenase inhibitory activity as well as for leukotriene receptor antagonistic properties. The results are presented in a tabular format, and a discussion about promising plant species and natural compounds as well as relevant in vitro assays are included in this article.