高效液相色谱法同时测定黄芩及其制剂中4种黄酮的含量

目的建立反相高效液相色谱法同时测定黄芩药材及其制剂中黄芩苷（1）、汉黄芩苷（2）、黄芩素（3）和汉黄芩素（4）的含量。方法采用Agilent Zorbax SB-C18色谱柱（4.6 mm×250 mm,5μm）;以乙腈-0.15%三氟乙酸水为流动相,梯度洗脱;流速：1.0 ml·min^-1;检测波长：280 nm;柱温：室温。结果已测定的4种黄酮在以下浓度范围内呈现良好的线性：（1）0.51～164 mg·L^-1（r=0.9999）,（2）0.33～104 mg·L^-1（r=0.9998）,（3）0.24～76 mg·L^-1（r=0.999 8）,（4）0.31～100mg·L^-1（r=0.9999）。平均回收率（n=3）分别为：（1）98.47%（RSD=1.35%）,（2）100.73%（RSD=0.57%）,（3）101%（RSD=2.63%）,（4）100.77%（RSD=0.27%）。结论该方法简便,准确,灵敏,结果可靠,可用于黄芩药材及其制剂的质量控制。     

Pharmacological effects and pharmacokinetics properties of Radix Scutellariae and its bioactive flavones

Radix Scutellariae is the dried root of the medicinal plant Scutellariae baicalensis Georgi. It exhibits a variety of therapeutic effects and has a long history of application in traditional formulations as well as in modern herbal medications. It has been confirmed that flavonoids are the most abundant constituents and induce these therapeutic effects. Six flavones are proven to be the major bioactive flavones in Radix Scutellariae existing in the forms of aglycones (baicalein, wogonin, oroxylin A) and glycosides (baicalin, wogonoside, oroxylin A-7-glucuronide). All six flavones are pharmacologically active and show great potential in the treatment of inflammation, cancers and virus-related diseases. The current review covers the preparation of the herb Radix Scutellariae, quantification of its major bioactive ingredients, and pharmacological effects of the proposed six bioactive flavones. In addition, this review summarizes the pharmacokinetic profiles of the bioactive flavones reported so far that could be used for further improvement of their pharmacokinetic study. Moreover, due to abundant co-occurring bioactive components in Radix Scutellariae, our review further documents the pharmacokinetic interactions among them.     

Pharmacokinetic interactions among major bioactive components in Radix Scutellariae via metabolic competition

Baicalein (B), wogonin (W) and oroxylin A (OA) are major components in Radix Scutellariae with similar pharmacokinetic properties. Due to the co‐presence of these three flavones in herbal formulations for Radix Scutellariae, they are likely consumed together. The aim of this study is to investigate whether the pharmacokinetics of individual flavones is influenced by each other and the underlying mechanism of the interaction. Various systems were utilized in the current study including a rat in vivo study, a Caco‐2 cell monolayer model and a rat in situ single‐pass intestinal perfusion as well as in vitro enzymatic kinetics studies. The B, W and OA given singly as well as in a mixture were administered and the corresponding pharmacokinetic parameters were calculated and compared. After co‐administration of the three flavones to rats, OA absorption increased significantly in comparison with when OA was administered alone. Mechanistic studies on the Caco‐2 cell monolayer and rat in situ single‐pass intestinal perfusion models revealed that co‐administration of B, W and OA could significantly enhance their absorption and decrease the extent of phase II metabolism. Further in vitro enzymatic study and a transport study in transfected MDCK cells revealed that metabolic competition rather than membrane transporters might contribute to the pharmacokinetic interactions. The co‐presence of multiple active components would result in metabolic interactions, which may induce further changes in pharmacodynamics. Copyright © 2012 John Wiley & Sons, Ltd.     

采用UFLC-IT-TOF/MS鉴定大鼠口服黄芩提取物后胆汁、血浆和尿液中的主要成分(英文)

黄酮类化合物是中国传统中药黄芩的主要活性成分。大鼠口服黄芩提取物后, 采用超快速液相色谱-离子阱飞行时间质谱(UFLC-IT-TOF/MS)对胆汁、血浆和尿液进行分析, 鉴定入血成分和代谢产物。根据对这些成分质谱裂解规律的分析, 共鉴定了36种不同的黄酮类化合物, 其中包括13个新的代谢产物。本实验在体外对黄芩提取物进行分析,鉴定了其中16个黄酮类成分, 大鼠胆汁中鉴定了25个黄酮类化合物, 血浆中15个黄酮类化合物, 尿液中14个黄酮类化合物。结果表明, 黄芩提取物中的黄酮类化合物以葡萄糖醛酸化、硫酸化和甲基化的为主要代谢途径。本实验首次对黄芩提取物的代谢产物进行综合分析。     

黄芩及其炮制品黄芩片的HPLC指纹图谱研究

目的对黄芩药材及其炮制品黄芩片进行HPLC指纹图谱研究。方法选择HPLC-UV指纹图谱。色谱条件：Hypersil C18柱（200mm×5.0mm,5μm）;流动相为甲醇-0.4%磷酸水溶液-乙腈线性梯度洗脱;流速：1.0mL·min^-1;柱温28℃;检测波长277nm。结果10批不同产地正品黄芩进行规范炮制加工后得到的黄芩片指纹图谱无明显差异,14个不同产地黄芩药材的指纹图谱也具有极高的相似度。结论该方法重复性好,可为黄芩药材及其饮片的质量控制提供科学依据。     

静脉注射黄芩总苷后黄芩苷在大鼠血浆及大脑皮层的药物动力学比较

黄芩苷(Baicalin)是常用中药黄芩的主要活性成分之一,具有解热、抗氧化等作用,近来研究表明黄芩苷还具有中枢镇静和脑保护作用[1,2].但黄芩苷能否透过血脑屏障分布至脑核团,至今未见报道.为此,本实验主要对黄芩总苷中黄芩苷在大鼠大脑皮层的分布及其规律进行了研究,并与其在血中的动力学变化进行了比较.     

高效液相色谱法测定柴胡和黄芩配伍的化学成分变化

目的:研究柴胡和黄芩配伍后化学成分在质和量上的变化。方法:采用HPLC法比较柴胡-黄芩单煎液与合煎液中各成分的变化。结果:柴胡-黄芩配伍后大多数化学成分在质和量上没有变化,少数化学成分含量发生了增减变化,发现有成分种类的减少,但未发现增加。结论:中药复方的配伍并不是单味中药的简单相加,而是有一定科学依据的。     

不同来源黄芩药材HPLC指纹图谱比较

目的对不同来源黄芩药材进行HPLC指纹图谱的比较研究。方法选择HPLC UV指纹图谱分析条件 :天津深航ZirchromKromasilC8色谱柱 (5 μm,2 0 0mm× 4 6mm) ;流动相为甲醇 水 (V∶V =5 2∶48) ,含 8mmol·L-1四丁基溴化铵 ,磷酸调pH2 8;检测波长为 2 76nm。以系统聚类分析进行分类 ,用计算机辅助相似度计算软件进行指纹图谱相似度比较。结果系统聚类分析将样品分为 5类 ,正品黄芩、滇黄芩、甘肃黄芩各分为 1类 ;2份粘毛黄芩各分为 1类。滇黄芩与正品黄芩的指纹图谱差异较明显 ,而粘毛黄芩、甘肃黄芩与正品黄芩指纹图谱无明显差异 ,不同产地正品黄芩间指纹图谱无明显差异。结论该方法能较好地识别黄芩药材的种类 ,为黄芩药材质量评估提供有益的信息。     

黄芩提取物中有效成分黄芩苷和汉黄芩苷在糖尿病大鼠中的药动学研究

目的比较黄芩提取物中主要成分黄芩苷和汉黄芩苷在糖尿病大鼠和正常大鼠体内的药动学.方法腹腔注射链脲佐菌素建立糖尿病大鼠模型,灌胃黄芩提取物后取血分离血浆,采用HPLC-Uv法检测血浆中黄芩苷和汉黄芩苷浓度,以矩量法计算药动学参数,AUC(0-τ)的计算采用梯形法.采用黄芩提取物与大鼠粪便温孵,从肠道代谢研究黄芩苷和汉黄芩苷动力学改变的初步机制.结果与正常大鼠比较,糖尿病大鼠给予黄芩苷和汉黄芩苷后体内Cmax1明显增加[黄芩苷(6.07±0.95)vs.(17.01±3.60)μg·mL-1,P＜0.01;汉黄芩苷(3.50±0.72)vs.(9.34±2.04)μg·mL-1,P＜0.01],Cmax2明显增加[黄芩苷(1.61±0.18)vs.(7.39±3.04)μg·mL-1,P＜0.01;汉黄芩苷(1.95±0.52)vs.(6.72±2.60)μg·mL-1,P＜0.01],AUC(0-τ)也明显增加[黄芩苷(38.72±7.25)vs.(86.70±20.91)μg·mL-1·h,P＜0.01;汉黄芩苷(39.20±12.10) vs.(69.40±24.20)μg·mL-1·h,P＜0.01],粪便悬浮液中黄芩苷降解也加快(Ke0.087 vs.0.173 min-1).结论黄芩苷和汉黄芩苷在糖尿病大鼠与正常大鼠之间存在明显的药动学差异,在糖尿病大鼠肠道内代谢加快.     

GC法检测黄芩中三种农药残留量

目的建立黄芩中的六六六（BHC）、滴滴涕（DDT）和五氯硝基苯（PNCB）3种农药残留量的毛细管气相色谱测定方法。方法样品采用丙酮-二氯甲烷为提取溶剂,以超声法提取,采用磺化法净化。检测使用弹性毛细管柱为分离柱,电子捕获检测器（ECD）检测。结果 3种成分在25min内得到良好的分离;两个色谱峰之间的分离度最小为1.57,峰与峰之间达到良好分离;该法中9个农药残留物组分的线性关系良好,其平均加样回收率为72.20%～116.18%,RSD值为0.55%～7.81%。结论该法准确,灵敏度高,易操作,重复性良好。     

近五年黄芩药理学研究进展

通过查阅近五年来国内外黄芩药理作用的研究文献,总结了近五年来国内外对黄芩药理作用研究的最新动向和进展,展望了黄芩药理作用今后的研究方向,为黄芩的现代化研究提供参考与借鉴。     

HPLC法测定广东土牛膝中二羟基泽兰素的含量

目的建立广东土牛膝中二羟基泽兰素含量的高效液相测定方法。方法 采用高效液相色谱法,色谱柱为Diamonsil C18柱(250mm×4.6 mm,5μm),流动相为乙腈-0.2%(V/V)磷酸水梯度洗脱,流速为1.0 ml/min,检测波长240 nm。结果二羟基泽兰素在0.58～6.96μg/ml浓度范围内有良好的线性关系(r=0.999 8),平均加样回收率为99.65%,RSD为0.8%(n=6)。结论该方法简便、灵敏,准确,可用于广东土牛膝的质量控制。     

气相色谱-质谱联用分析黄连、黄芩、白芍合煎液中挥发性成分

目的:定性分析黄连阿胶汤中黄连、黄芩、白芍单煎液与合煎液中的挥发性成分,研究其对合煎液中挥发性成分的归属以及在煎煮过程中可能发生的变化.方法:分别用石油醚萃取黄连、黄芩、白芍3味药的单煎液与合煎液,浓缩萃取物并定容至1 mL,使用Agilent GC-MS色质联用仪和HP-5 MS毛细管柱对样品进行分析.柱温程序为50℃保温5 min,8℃/min,升温至250℃.结果:共鉴定出了19个主要化合物.结论:除19号峰外,单煎液中的挥发性成分均在合煎液中检出.     

甘肃产四倍体黄芩与二倍体黄芩止血作用的比较

目的 比较甘肃产四倍体黄芩与二倍体黄芩的止血作用。方法 将70只SD大鼠随机分为正常对照组、模型对照组、阳性对照组、二倍体黄芩生品组、二倍体黄芩炭品组、四倍体黄芩生品组、四倍体黄芩炭品组。除正常对照组外,其余各组给予5%的乙醇自由饮用,并给予干姜水煎液灌胃,连续造模15 d。第15天造模后7 h,各给药组按10 g·kg^-1剂量灌胃给予相应黄芩水煎液,连续给药7 d,检测各组大鼠出血时间(bleeding time,BT)、血浆复钙时间(plasma recalcification time,PRT)、凝血功能4项。结果 与正常对照组比较,模型对照组大鼠BT、PRT、凝血酶原时间(PT)、凝血酶时间(thrombin time,TT)、活化部分凝血活酶时间(activated partial thromboplastin time,APTT)显著延长(P<0.05),纤维蛋白原(fibrinogen,FIB)含量显著增加(P<0.05);与模型对照组比较,各药物组大鼠BT、PRT、PT、TT、APTT时间均显著缩短(P<0.05),FIB含量显著降低(P<0.05);与同一品种生品组比较,二倍体黄芩炭品、四倍体黄芩炭品组大鼠BT、PRT、PT、TT、APTT时间均显著缩短(P<0.05)。结论 甘肃产四倍体黄芩与二倍体黄芩水煎液止血作用无显著差异,而炭品的止血效果显著优于同品种生品。     

Influence of cholestyramine on the pharmacokinetics of rosiglitazone and its metabolite,desmethylrosiglitazone, after oral and intravenous dosing of rosiglitazone: Impact on oral bioavailability,absorption, and metabolic disposition in rats

The possible influence of the bile acid-sequestering agent cholestyramine (CSA), which is a basic co-medication in hypercholesterolemic patients, on the pharmacokinetics of rosiglitazone (RGL) and its circulating metabolite desmethylrosiglitazone (DMRGL) was investigated following a single oral and intravenous dose of RGL to Wistar rats. The pharmacokinetic parameters of RGL and DMRGL were evaluated following oral or intravenous administration of RGL to rats at 10?mg?kg^?1 with and without pre-treatment (0.5?h before RGL administration) of CSA at 0.057, 0.115, 0.23 and 0.34?g?kg^?1 doses. With an increase in CSA dose there was dose-dependent decrease in area under the curve (AUC)_(0?∞) and C_max with no change in T_max, K_el and t_1/2 values for both RGL and DMRGL following oral administration of RGL. The oral bioavailability of RGL was reduced by 19.9, 35.6, 53.8 and 72.0% in rats following pre-treatment with CSA at 0.057, 0.115, 0.230 and 0.340?g?kg^?1, respectively. There was no change in the above-mentioned pharmacokinetic parameters for RGL and DMRGL in rats when RGL was given intravenously following pre-treatment with the above-mentioned oral doses of CSA. Another objective of the study was to determine the effect of staggered oral CSA dosing at 1, 2 and 4?h after oral RGL administration at 10?mg?kg^?1. AUC_(0?∞) of RGL and DMRGL was reduced following CSA staggered administration at 1?h, whereas 2- and 4-h staggered dose administration of CSA had no effect on the AUC_(0?∞) of RGL and DMRGL. Irrespective of CSA staggered dose administration there was no change in other pharmacokinetic parameters, namely C_max, T_max, K_el and t_1/2. The apparent formation rate constant (K_f) of DMRGL was also calculated to show that only the absorption of RGL was affected, not the apparent formation rate of DMRGL. The authors also studied the in vitro adsorption of RGL (100, 250, 500?µg?ml^?1) at various pH conditions (pH 2, 4 and 7) and different concentrations of CSA (15, 30, 60 and 120?mg?ml^?1). The percentage binding of CSA was in the range 50–72% (at pH 2), 74–89% (at pH 4) and 97–100% (at pH 7). In conclusion, we carried out a systematic investigation demonstrating mechanistically the interaction potential of RGL when co-administered with CSA. The applicability of the metabolite data after intravenous and oral dosing and pH-based binding experiments further adds credence to the key findings.     

Dose-independent pharmacokinetics of torasemide after intravenous and oral administration to rats

After intravenous (at doses of 1, 2, 5, and 10 mg/kg) and oral (at doses of 1, 5, and 10 mg/kg) administration of torasemide, the pharmacokinetic parameters were dose-independent. Hence, the extent of absolute oral bioavailability (F) was also independent of oral doses; the values were 95.6, 98.8, and 97.3% for oral doses of 1, 5, and 10 mg/kg, respectively. The high F values indicated that the first-pass (gastric, intestinal, and hepatic) effects of torasemide in rats could be almost negligible. After intravenous administration, the total body clearances of torasemide were extensively slower than the reported cardiac output in rats and hepatic extraction ratio was only 3-4% suggesting almost negligible first-pass effects of torasemide in the heart, lung, and liver in rats. Based on in vitro rat tissue homogenate studies, the tissues studied also showed negligible metabolic activities for torasemide. Equilibrium of torasemide between plasma and blood cells of rat blood reached fast and plasma-to-blood cells concentration ratio was independent of initial blood concentrations of torasemide, 1, 5, and 10 microg/ml; the mean value was 0.279. Protein binding of torasemide to fresh rat plasma was 93.9 +/- 1.53% using an equilibrium dialysis technique.     

宁夏黄芩不同干燥方法与药材质量的相关性研究

目的研究宁夏栽培黄芩采用不同干燥方法进行产地加工时药材中4种化合物成分的变化规律,确定最佳产地加工干燥方法。方法采用HPLC法评价不同干燥方法的黄芩药材中4种化合物的含量。结果 80℃为最佳干燥温度。结论黄芩产地鲜切为最佳加工方法,即将黄芩鲜药材蒸30min后切片,置于烘箱中80℃烘干。其结果可为规范黄芩产地加工提供依据。     

不同配伍比例下生姜对黄芩中化学成分溶出率的影响

目的 探讨黄芩配伍不同比例生姜前后黄芩中化学成分溶出率的变化,基于微观量化标准揭示“生姜恶黄芩”的科学内涵,为临床应用提供一定的科学参考。方法 采用Agilent C₁₈色谱柱（4.6 mm×150 mm,5 μm）,流动相为甲醇和0.1%磷酸梯度洗脱,柱温30 ℃,进样量20 μL,流速1 mL·min^-1,检测波长280 nm。建立黄芩-生姜不同比例提取液的HPLC色谱图,以黄芩单品图谱为对照,标定共有峰,分析不同配伍比例下各图谱的变化,考察黄芩特征峰相对峰面积与配伍比例的关系,并分析黄芩中4种指标性成分的含量变化。结果 黄芩单品提取液分离得到30个色谱峰,其中15,19,24和29号峰分别为黄芩苷、汉黄芩苷、黄芩素和汉黄芩素;不同配伍比例中共有峰为22个,与单品图谱相比较,其余配伍比例中均存在黄芩特征峰消失现象,且不同比例下消失峰的种类和数目存在差异;与黄芩单品相比,各比例中除个别色谱峰外黄芩特征峰相对峰面积总体上呈不同程度的下降,其中黄芩-生姜1∶1中下降程度最小,且此比例下除黄芩苷外,汉黄芩苷、黄芩素及汉黄芩素的含量较单品下降程度均不明显,而在其余比例中4成分的含量下降程度均显著（P<0.05）。结论 黄芩配伍不同比例生姜后,总体降低了黄芩中化学成分的溶出率,但不是所有成分的溶出率均降低;黄芩-生姜1∶1配伍对黄芩溶出率的影响最小。     

Urinary pharmacokinetics of baicalein,wogonin and their glycosides after oral administration of Scutellariae Radix in humans

Baicalin, baicalein, wogonoside and wogonin are flavone constituents of Scutellariae Radix with various beneficial biological activities. The purpose of this study was to investigate the urinary pharmacokinetics of these flavones after oral administration of Scutellariae Radix commercial powder. Ten healthy male volunteers received a dose of 5.2 g commercial powder (comparable to 9 g crude drug), respectively. The concentrations of baicalin, baicalein and wogonin in the commercial powder as well as their metabolites in urine were assayed by HPLC method. The glucuronides and sulfates of baicalein and wogonin in urine were hydrolyzed with beta-glucuronidase and sulfatase, respectively. Our results showed that the mean cumulated renal excretion of baicalein glucuronides and sulfates were 43.1+/-4.5 micromol (2.9% of dose) and 64.8+/-6.3 micromol (4.3% of dose), respectively, whereas wogonin glucuronides and sulfates were 21.6+/-2.0 micromol (5.9% of dose) and 20.7+/-1.7 micromol (5.7% of dose), respectively. The result indicated that the renal excretion of conjugated metabolites of wogonin (11.6% of dose) were higher than that of baicalein (7.2% of dose). The baicalein sulfates was predominant than the corresponding glucuronides, whereas wogonin sulfates was comparable to the corresponding glucuronides.     

RP—HPLC法测定7种药用黄芩中黄芩苷和汉黄芩苷的含量

目的:建立测定7种药用黄芩中黄芩苷和汉黄芩苷的反相高效液相色谱法,7种药用黄芩为黄芩,粘毛黄芩,甘肃黄芩,滇黄芩,韧黄芩,川黄芩和丽江黄芩。方法:采用Wakosil;C_(18)柱(150mm×4.6mm,5μm),以甲醇-水-冰乙酸(41:59:0.2)和(36:64:0.2)为流动相,流速为1.0mL·min~(-1),检测波长为280nm。应用二极管阵列检测器对峰的纯度进行鉴定。结果:样品中黄芩苷和汉黄芩苷平均回收率分别为98.3％和96.8％,RSD分别为0.48％和1.3％,n=5;黄芩苷在0.08～0.4μg内,r=0.9998,汉黄芩苷在0.04～0.2 μg内,r=0.9995;峰面积与浓度线性关系良好。结论:黄芩苷、汉黄芩苷与其他成分能得到很好的分离,不同品种间2种苷含量差别比较大。