超高效液相色谱法测定钩藤中的钩藤碱和异钩藤碱的含量

目的:用超高效液相色谱法同时测定钩藤中的钩藤碱和异钩藤碱的含量。方法:以ACQUITYUPLCR BEH130C18(2.1mm×100mm,1.7μm)为色谱柱,乙腈-0.01mol/L三乙胺水溶液(45:55,冰醋酸调pH7.0)为流动相,检测波长为245nm,流速0.2mL/min。结果:钩藤碱在0.052-0.309μg具有良好的线性关系,r=0.9997,平均回收率为98.3%,RSD为0.88%,异钩藤碱在0.060μg-0.363μg具有良好的线性关系,r=0.9999,平均回收率为97.7%,RSD为1.29%。结论:该方法简便快捷、精密度高、结果准确。可用于钩藤的质量控制。     

钩藤中不同成分降压作用的差异

目的：比较钩藤中提取的异钩藤碱、钩藤碱、钩藤总碱及非生物碱部分的降压作用。方法：大鼠麻醉后经颈总动脉插管记录外周血压和经股静脉微量输注实验用药。结果：实验表明钩藤中４种成分的降压强度为异钩藤碱（４２．０％）〉钩藤碱（３２．１％）〉钩藤总碱（２１．３％）〉钩藤非生物碱（１２．４％）。结论：提示钩藤中主要降压成分为异钩藤碱的钩藤碱。     

凯氏定氮测定钩藤饮片总氮含量研究

目的 优选凯氏定氮法测定钩藤饮片总氮含量的条件参数,探索将总氮量作为钩藤饮片质量评价参考指标的可行性.方法 采用均匀设计法优化凯氏定氮仪(FOSS Kjeltec 8100)测定总氮的消解条件,并测定不同来源饮片总氮含量.结果 凯氏定氮仪测定的消解最佳条件为硫酸加入量为14 ml,硫酸钾加入量为7.0g,硫酸铜加入量为0.8g.结论 该方法快速、准确,重现性好,为钩藤饮片质量研究提供了新的参考.     

藏药萨折抗单胺氧化酶活性成分研究

目的分离鉴定藏药萨折中的单胺氧化酶抑制剂。方法运用硅胶、聚酰胺、凝胶柱色谱和HPLC分离纯化萨折的化学成分,并根据其理化性质和波谱数据鉴定化合物结构。采用Holt法进行抗单胺氧化酶活性测定。结果从萨折的乙醇提取物中分离得到3个化合物,分别鉴定为没食子酸(1),没食子酸甲酯(2),3,4,8,9,10-pentahydroxydibenzo[b,d]pyran-6-one(3)3个化合物。其对单胺氧化酶的半数抑制浓度(IC50)分别为10.0、35.9、35.2μmol/L。结论化合物3为首次从萨折中分离得到,化合物1³均具有较强单胺氧化酶抑制活性,其中化合物1活性最好,其IC50为10.0μmol/L。     

Monoamine oxidase inhibition by Rhodiola rosea L. roots

Aim of the study

Rhodiola rosea L. (Crassulaceae) is traditionally used in Eastern Europe and Asia to stimulate the nervous system, enhance physical and mental performance, treat fatigue, psychological stress and depression. In order to investigate the influence of Rhodiola rosea L. roots on mood disorders, three extracts were tested against monoamine oxidases (MAOs A and B) in a microtitre plate bioassay.

Materials and methods

Methanol and water extracts gave the highest inhibitory activity against MAOs. Twelve compounds were then isolated by bioassay-guided fractionation using chromatographic methods. The structures were determined by ¹H, ¹³C NMR and HR-MS.

Results

The methanol and water extracts exhibited respectively inhibitions of 92.5% and 84.3% on MAO A and 81.8% and 88.9% on MAO B, at a concentration of 100 μg/ml. The most active compound (rosiridin) presented an inhibition over 80% on MAO B at a concentration of 10⁻⁵ M (pIC₅₀ = 5.38 ± 0.05).

Conclusions

The present investigation demonstrates that Rhodiola rosea L. roots have potent anti-depressant activity by inhibiting MAO A and may also find application in the control of senile dementia by their inhibition of MAO B.     

三种一般钩藤ITS序列的RFLP分析

目的以核糖体转录间隔区(rDNA ITS)序列为分子标记,对采集自3个不同地区的一般钩藤Uncaria rhynchophylla(Miq.)Jack.进行RFLP遗传分析,研究不同地理区域一般钩藤的rDNA ITS序列是否具有生物地理差异。方法通过改良CTAB法提取一般钩藤总DNA,利用通用引物对其rDNA ITS序列进行PCR扩增,并对连接转化后扩增得到的rDNAITS序列进行限制性片段长度多态性(Restriction Fragment Length Polymorphism,RFLP)分析。结果获得采集自广东韶关阳山、广东梅州大埔、广西植物园的3种一般钩藤两种限制性内切酶(Msp I&HaeⅢ)酶切图谱。结论通过基于rDNAITS序列进行的RFLP分析,表明这3个地区的一般钩藤rDNA ITS序列无明显差异,不同区域的一般钩藤其遗传本质不具有地理差异。     

酸性染料比色法测定钩藤的总生物碱含量

目的：探讨钩藤中总生物碱含量测定的方法。方法：采用酸性染料比色法测定钩藤中总生物碱含量。结果：酸性染料比色法的显色条件为pH3．6缓冲液5．0ml，溴甲酚绿液5．0ml；氯仿萃取三次，每次4．0ml，每次萃取振摇2min，静置5min。钩藤碱在6．018μg-108．324μg范围内呈线性关系，回收率平均值97．19％，RSD=1．34％（n=6）。结果：该方法灵敏度高，准确度好、重现性好。     

Inhibition of phospholipase cgamma1 and cancer cell proliferation by triterpene esters from Uncaria rhynchophylla

Investigation of the hooks of Uncaria rhynchophylla resulted in isolation of six phospholipase Cgamma1 (PLCgamma1) inhibitors (1-6). The structures of these compounds were elucidated as pentacyclic triterpene esters by spectroscopic and chemical analysis. Three of them, namely uncarinic acids C (1), D (2), and E (3), are newly reported as natural products. All the compounds showed dose-dependent inhibitory activities against PLCgamma1 in vitro with IC(50) values of 9.5-44.6 microM and inhibited the proliferation of human cancer cells with IC(50) values of 0.5-6.5 microg/mL.     

不同产地及不同采收期钩藤中异钩藤碱的含量分析

目的：研究不同产地及不同采收期钩藤中异钩藤碱的含量。方法应用HPLC测定8个不同产地及不同采收期钩藤中异钩藤碱含量,采用Waters Symmetry C18色谱柱(250 mm34.6 mm,5μm),流动相为甲醇-0.01 mol/L醋酸铵缓冲液(pH 8.0)(60∶40),柱温25℃,进样体积20μl,流速1.0 ml/min,检测波长246 nm。结果不同产地及不同采收期的钩藤中异钩藤碱含量不同,其中含量最高的地区为宁明县;含量最高的采收时间为每年9月至次年2月。结论不同产地钩藤药材异钩藤碱的含量不同,每年9月至次年2月采收的钩藤中异钩藤碱含量较高。     

Oral Uncaria rhynchophylla (UR) reduces kainic acid-induced epileptic seizures and neuronal death accompanied by attenuating glial cell proliferation and S100B proteins in rats

Aim of the study

Epilepsy is a common clinical syndrome with recurrent neuronal discharges in cerebral cortex and hippocampus. Here we aim to determine the protective role of Uncaria rhynchophylla (UR), an herbal drug belong to Traditional Chinese Medicine (TCM), on epileptic rats.

Materials and methods

To address this issue, we tested the effect of UR on kainic acid (KA)-induced epileptic seizures and further investigate the underlying mechanisms.

Results

Oral UR successfully decreased neuronal death and discharges in hippocampal CA1 pyramidal neurons. The population spikes (PSs) were decreased from 4.1 ± 0.4 mV to 2.1 ± 0.3 mV in KA-induced epileptic seizures and UR-treated groups, respectively. Oral UR protected animals from neuronal death induced by KA treatment (from 34 ± 4.6 to 191.7 ± 48.6 neurons/field) through attenuating glial cell proliferation and S100B protein expression but not GABAA and TRPV1 receptors.

Conclusions

The above results provide detail mechanisms underlying the neuroprotective action of UR on KA-induced epileptic seizure in hippocampal CA1 neurons.     

Anticonvulsant effect of Uncaria rhynchophylla (Miq) Jack. in rats with kainic acid-induced epileptic seizure.

This study investigated the anticonvulsant effect of Uncaria rhynchophylla (UR) and the physiological mechanisms of its action in rats. A total of 70 male Sprague-Dawley (SD) rats were selected for study. Thirty four of these rats were divided into 5 groups as follows: 1) Control group (n = 6): received intraperitoneal injection (i.p.) of kainic acid (KA, 12 mg/kg); 2) UR1000 group (n = 10), 3) UR500 group (n = 6) 4) UR250 group, received UR 1000, 500, 250 mg/kg i.p. 30 min prior to KA administration, respectively; 5) Contrast group: received carbamazepine 20 mg/kg i.p. 30 min prior to KA administration. Behavior and EEG were monitored from 15 min prior to drug administration to 3 hours after KA administration. The number of wet dog shakes were counted at 10 min intervals throughout the experimental course. The remaining 36 rats were used to measure the lipid peroxide level in the cerebral cortex one hour after KA administration. These rats were divided into 6 groups of 6 rats as follows: 1) Normal group: no treatment was given; 2) Control group: received KA (12 mg/kg) i.p.; 3) UR1000 group, 4) UR500 group, 5) UR250 group, received UR 1000, 500, 250 mg/kg i.p. 30 min prior to KA administration, respectively; 6) Contrast group: received carbamazepine 20 mg/kg i.p. 30 min prior to KA administration. Our results indicated that both UR 1000 and 500 mg/kg decreased the incidence of KA-induced wet dog shakes, no similar effect was observed in the UR 250 mg/kg and carbamazepine 20 mg/kg group. Treatment with UR 1000 mg/kg, 500 mg/kg, or 250 mg/kg and carbamazepine 20 mg/kg decreased KA-induced lipid peroxide level in the cerebral cortex and was dose-dependent. These findings suggest that the anticonvulsant effect of UR possibly results from its suppressive effect on lipid peroxidation in the brain.     

Alkaloids from the leaves of Uncaria rhynchophylla and their inhibitory activity on NO production in lipopolysaccharide-activated microglia

Two new isomeric alkaloids, 18,19-dehydrocorynoxinic acid B (1) and 18,19-dehydrocorynoxinic acid (2), were isolated from the CHCl3 extract of the leaves of Uncaria rhynchophylla, together with four known rhynchophylline-type alkaloids, corynoxeine (3), isocorynoxeine (4), rhynchophylline (5), and isorhynchophylline (6), and an indole alkaloid glucoside, vincoside lactam (7). The structures of compounds 1 and 2 were elucidated by spectroscopic methods including UV, IR, HREIMS, 1D and 2D NMR, and CD experiments. The activity assay showed that compounds 3-6, with a C-16 carboxylic ester group, and 7 exhibited inhibitory activity on lipopolysaccharide (LPS)-induced NO release in primary cultured rat cortical microglia (IC 50: 13.7-19.0 microM). However, only weak inhibitory activity was observed for compounds 1 and 2, with a C-16 carboxylic acid group (IC 50: >100 microM).     

Macrophyllionium and macrophyllines A and B, oxindole alkaloids from Uncaria macrophylla

An unusual oxindole alkaloid inner salt, macrophyllionium (1), and a pair of new tetracyclic oxindole alkaloids, macrophyllines A (2) and B (3), together with six known alkaloids, were isolated from the aerial parts of Uncaria macrophylla. Corynantheidine (8) exhibited moderate cytotoxicity against HL-60 and SW480 cells with IC(50) values of 13.96 and 23.28 μM, respectively. Dihydrocorynantheine (9) exhibited significant vasodilating activity against phenylephrine-induced contraction in rat thoracic aorta rings (IC(50) = 6.73 μg/mL). In addition, compounds 2, 6, and 9 showed weak inhibitory action on KCl-induced contraction.     

New trends in the separation of active principles from plants

The extraction and separation of active principles of plant constituents is a difficult task, even for specialized chemists, when many similar substances are found in a single plant.In the case of the presence of alkaloids a separation method based on counter-current distribution with a discontinuous variation of pH can be used for the resolution of very complex mixtures.The alkaloids separated from twenty-seven medicinal plants are reported.     

Possible involvement of amine oxidase inhibition in the sympathetic activation induced by khat (Catha edulis) chewing in humans

The possibility that phenylalkylamines (cathinone and cathine) of khat, like amphetamines, are amine oxidase inhibitors with clinical significance is evaluated. Results show that khat chewing induces a significant increase in blood pressure, body temperature and urinary catecholamines in khat naive subjects. On the other hand, in habitual consumers a significant enhancement only of blood pressure is observed. Urinary concentrations of vanilmandelic acid show an inhibitory trend in both groups of subjects. This has been related to a decrease in catecholamine deamination. In fact, oxidative deamination of benzylamine catalyzed by beef plasma amine oxidase is non-competitively inhibited in vitro by cathinone (Ki = 0.05 mM) and cathine (Ki = 10 mM) as well as by amphetamine (Ki = 7.9 mM).     

Anti-inflammatory activity of two different extracts of Uncaria tomentosa (Rubiaceae)

We assessed in vivo the anti-inflammatory activity of two Cat's claw bark extracts, by comparing a spray-dried hydroalcoholic extract against an aqueous freeze-dried extract, to determine which extract was more effective. We used the carrageenan-induced paw edema model in mice. In addition, to assess the molecular mechanism of action, we determined the inhibition of NF-kappa B through the Electrophoretic Mobility Shift Assay (EMSA) and the effects on cycloxygenase-1 and -2. Results showed that the anti-inflammatory activity was significantly higher using the hydroalcoholic compared with the aqueous extract (P<0.05). The extracts also showed little inhibitory activity on cyclooxygenase-1 and -2. It cannot be excluded that the slight inhibitory activity on DNA binding of NF-kappa B is due to cytotoxic effects.     

3种广西钩藤属药用植物的RAPD多态性分析

目的运用随机扩增多态性技术探索广西钩藤属药用植物的遗传多态性,为其种质鉴定提供依据。方法采用优化的试剂盒提取法提取大叶钩藤、白钩藤、毛钩藤3种植物的总DNA。用经过筛选的18条10个碱基的随机引物进行PCR扩增。结果优化后的试剂盒提取法可有效获取3种钩藤属植物的基因组DNA,18条随机引物扩增得到条带共260条,其中多态性条带231条,多态率达到88.9%,扩增效果好。按UPGMA法进行聚类分析,计算其遗传相似系数,结果显示,5份钩藤供试材料聚为3类。结论 3种广西钩藤属药用植物的聚类结果与其种和地理区域远近一致,与形态学观察可能存在差异。所得RAPD标记可用于钩藤属药用植物的多态性研究,并为今后开发遗传鉴定的分子标记奠定基础。     

Biologically active compounds from Aphyllophorales (polypore) fungi

This review describes biologically active natural products isolated from Aphyllophorales, many of which are known as polypores. Polypores are a large group of terrestrial fungi of the phylum Basdiomycota (basidiomycetes), and they along with certain Ascomycota are a major source of pharmacologically active substances. There are about 25 000 species of basidiomycetes, of which about 500 are members of the Aphyllophorales, a polyphyletic group that contains the polypores. Many of these fungi have circumboreal distributions in North America, Europe, and Asia and broad distributions on all inhabited continents and Africa; only a small number of the most common species with the most obvious fruiting bodies (basidiocarps) have been evaluated for biological activity. An estimated 75% of polypore fungi that have been tested show strong antimicrobial activity, and these may constitute a good source for developing new antibiotics. Numerous compounds from these fungi also display antiviral, cytotoxic, and/or antineoplastic activities. Additional important components of this vast arsenal of compounds are polysaccharides derived from the fungal cell walls. These compounds have attracted significant attention in recent years because of their immunomodulatory activities, resulting in antitumor effects. These high molecular weight compounds, often called biological response modifiers (BRM), or immunopotentiators, prevent carcinogenesis, show direct anticancer effects, and prevent tumor metastasis. Some of the protein-bound polysaccharides from polypores and other basidiomycetes have found their way to the market in Japan as anticancer drugs. Finally, numerous compounds with cardiovascular, phytotoxic, immunomodulatory, analgesic, antidiabetic, antioxidant, insecticidal, and nematocidal activities, isolated from polypores, are also presented. In fact many of the fungi mentioned in this paper have long been used in herbal medicine, including polypores such as Ganoderma lucidum (Reishi or Ling Zhi), Laetiporus sulphureus (Chicken-of-the-Woods), Trametes versicolor (Yun Zhi), Grifola umbellata (Zhu Lin), Inonotus obliquus (Chaga), and Wolfiporia cocos (Hoelen).     

Hepatitis B surface antigen (HBsAg) inactivation and angiotensin-converting enzyme (ACE) inhibition in vitro by Combretum glutinosum perr. (Combretaceae) extract

Among the aqueous extracts of ten African medicinal plants traditionally used for the treatment of hepatic disease and which can inhibit hepatitis B virus antigen (HBsAg) in vitro, extracts from the leaf decoction of Combretum glutinosum proved to be the most active (100–500 ng/mL^?1). With solvents of increasing polarity, a precipitate was isolated from the methanolic phase of this extract which contains gallic tannins and these compounds may be responsible for the effect on angiotensin-converting enzyme (ACE).