Effect of Pueraria Flavonoid on Diabetes in Mice Complicated by Hyperlipidemia

A new model is presented for hyperglycemia in animals complicated by hyperlipidemia (HD) to study the action of pueraria flavonoids (PF). Kunming mice were treated with alloxan (150 mg/kg) intraperitoneally and fed a high fat diet. Glucose (Glu), total cholesterol (TC) and triglycerides (TG) in the plasma were measured at week 0, 1, 2, 4, and 8. PF (600, 400, 200 mg/kg) was given to the mice for 14 days beginning from week 1. The effects of PF on the lipase activity and the ability to produce cholesterol and glycogen in the cultured hepatic cells were also tested in vitro. In week 1, 2, 4, and 8 following the final alloxan injection, Glu increased by 763%, 504%, 526%, and 641%;TC increased by 269%, 409%, 449%, and 428%; and TG increased by 415%, 485%, 461%, and 418%. These increases in the model were significant compared with those in normal Kunming mice. PF acted effectively as hypoglycemic and hypolipidemic agents on the mice. The results suggest that the model may be suitable for studies of drugs on diabetes complicated by hyperlipidemia and that PF may be a useful drug for patients with diabetes complicated by hyperlipidemia.

Kinetics of Leaching Flavonoids from Pueraria Lobata with Ethanol

The kinetics of leaching flavonoids from Pueraria Lobata with ethanol was investigated. The effects of leaching temperature, mechanical agitation rate,concentration of ethanol and feed particle size on leaching kinetics were examined.It is found that the smaller the feed particle size or the higher the leaching temperature,the higher the leaching rate. The leaching process can be described by the shrinking-core model. The apparent activation en- ergy is 10.8kJ·mol-1, suggesting that the leaching process is controlled by the inner diffusion. An empirical equa- tion relating the flavonoids leaching rate constant to the feed particle size and leaching temperature was expected.

Extraction and separation of total flavonoids from Flos Puerariae and its antioxidant activity

Objective To study the optimum extraction and separation process of total flavonoids in the flowers of Flos Puerariae and its antioxidative activity.Methods The total flavonoids were extracted with assistance of ultrasonic wave and the content was determined at 265 nm wavelength by Spectrophotometric method.Orthogonal experiment L9(34)was carried out to investigate the effects of concentration of solvent,the ratio of material to liquid,time length of extraction,and frequency of extraction on extraction results of total flavonoids from Flos Puerariae.The extracted solution was purified by petroleum ether and ethanol sequently.Under these conditions,the total flavonoids was eluted gradiently with mixed mobile phase of methanol-chloroform solution in the silica gel column system,and then determined by UV scanning and HPLC.Fenton reaction was used to produce and detect hydroxyl radicals(·OH),and pyrogallol system was used to produce and detect the superoxide radical anion(O2-·).Results The optimum conditions were as follows;using 40%(V/V)methanol as extractor with the ratio of material to liquid at 1∶30,and extracting for 2.5 h a time for 3 times.The extraction yield of total flavonoids was 13.6%.Six isoflavone compounds were isolated from the flowers of Flos Puerariae by the method of silica gel column chromatography.Antioxidative test results showed good performance of flavonoid scavenging capacity in both hydroxyl radical system and superoxide radical system and its IC50 was 7.65 μg·mL-1 and 0.18 mg·mL-1,respectively.Conclusions This study provided scientific basis for further development and utilization of Flos Puerariae and make preparation for later pharmacological research.

Extraction Technology of Total Flavonoids from Pueraria lobata (Willd.) Ohwi and Content Determination of Pueraria lobata (Willd.) Ohwi at Different Altitudes

[Objectives]To optimize the extraction technology of total flavonoids from Pueraria lobata( Willd.) Ohwi. [Methods]The ultraviolet-visible spectrophotometry was used to determine the content of total flavonoids in Pueraria lobata( Willd.) Ohwi. With the puerarin as index,the reflux extraction and single factor test were employed to investigate the effects of temperature,time,ethanol concentration and solid-liquid ratio on the content of total flavonoids in Pueraria lobata( Willd.) Ohwi,respectively. Under the optimal extraction technology,the content of total flavonoids in Pueraria lobata( Willd.) Ohwi at different altitudes was determined.[Results] The optimum extraction process was as follows: 70%ethanol; solid-liquid ratio of 1∶ 30; 1 h reflux extraction. Under these conditions,the extraction rate of flavonoids in Pueraria lobata( Willd.) Ohwi was 11. 48%,the total flavonoids content of different kudzu parts was in the order of roots > stems > leaves,and the total flavonoids content of the sample at about an altitude of 1000 m was significantly higher than at the altitudes of 1400 m and 1700 m.[Conclusions]It was suggested that the Pueraria lobata( Willd.) Ohwi should not be cultivated as medicinal plant in too high mountains,and the stems and leaves of Pueraria lobata( Willd.) Ohwi could be used as raw materials for extracting total flavonoids.

葛根中总黄酮含量测定方法比较研究

目的:紫外-可见分光光度测定葛根总黄酮含量的两种方法(显色法、直接测定)结果具有显著差异,因此将两种测定方法与HPLC法进行对比,找出导致其差异的原因和解决方案。方法:以芦丁为对照品,采用亚硝酸钠-硝酸铝-氢氧化钠显色,通过UV法测定葛根总黄酮含量;以葛根素为对照品,直接于250 nm处测定吸光度计算葛根总黄酮含量;采用高效液相色谱法测定葛根素的含量,对比三种方法的含量差异,评价两种紫外测定法所得结果的准确性。结果:显色法测定23批野葛总黄酮含量为0.93%~8.02%,23批粉葛总黄酮含量为0.04%~1.12%,直接测定法测得23批野葛总黄酮含量为3.31%~15.74%,23批粉葛总黄酮含量为0.80%~7.59%;显色法测得葛根总黄酮含量均显著低于非显色法。HPLC测定23批葛根的葛根素含量为1.98%~5.85%,23批粉葛的葛根素含量为0.17%~2.37%。结论:显色法测定的总黄酮含量大部分低于单一成分葛根素的含量,不显色法测得总黄酮含量均高于单一成分葛根素的量。在葛根总黄酮的测定中,以葛根素为对照品的直接测定法更加合理准确。

葛根黄酮浸取工艺优化研究

通过六组单因素试验和四因素正交试验探讨了葛根黄酮的最佳浸取工艺。结果表明：在温度８５℃、ｐＨ值为８的条件下，用１０倍于葛根量的浓度为７０％的乙醇，浸取２次，每次３ｈ，葛根黄酮浸取效果最好，得率在９％以上、浸出物黄酮含量大于４０％。

葛根黄酮降血糖防治糖尿病并发症的实验研究

通过尾静脉注射四氧嘧啶(50mg/kg体重)建立糖尿病小鼠模型,实验分为正常组、糖尿病组、糖脉康药物对照组和葛根黄酮组,实验40d后检测各组动物体重、饮水量、血糖、糖耐量、果糖胺、山梨醇、醛糖还原酶、山梨醇脱氢酶和糖基化终产物(AGEs)等实验指标.结果表明,葛根黄酮能明显改善糖尿病小鼠的病理症状,降低血糖水平,降低血液中果糖胺、山梨醇、醛糖还原酶和AGEs的含量,升高血液中山梨醇脱氢酶的含量,同时还能降低肝脏、肾脏、大脑、心脏和皮肤组织中AGEs和山梨醇的含量,与糖尿病组小鼠比较差异显著(P<0.01).由此得出结论,葛根黄酮除具有明显降血糖作用外,还对糖尿病并发症有一定的预防和治疗效果.

响应面法优化葛根总黄酮的超声辅助提取工艺

为提高葛根总黄酮的得率,采用响应面试验设计优化超声辅助提取葛根总黄酮的工艺条件。在单因素试验基础上确定以超声时间、料液比及超声温度为3个主要因素,以总黄酮得率为响应值,根据Box-Behnken原理采用三因素三水平响应面试验设计进行优化。结果表明超声辅助法提取葛根总黄酮的最佳工艺条件为:以蒸馏水作为超声提取溶剂,超声时间43min、料液比1:10(g/mL)、超声温度68℃,总黄酮得率为5.28%,与预测得率5.36%相比,相对误差仅为1.4 9%。说明该模型可靠,与实际情况拟合较好。

超声波预处理微波萃取葛根总黄酮的工艺优化

以湘西野葛根为原料,优化葛根总黄酮超声微波双辅助萃取工艺。研究超声提取温度、超声作用时间、微波功率、微波作用时间、固液比5个影响因素对葛根总黄酮提取量的影响,采用紫外分光光度计测定葛粉中总黄酮的含量,建立葛根总黄酮的最佳提取工艺条件。结果表明,在以80%的乙醇为提取溶剂、微波辐射功率300W、微波辐射时间9min、固液比1:25(g/mL)、超声提取温度50℃、超声提取时间30min的条件下,总黄酮的提取量可达14.685mg/g。

抗氧化效应法研究葛根黄酮微丸的药动学

目的:研究葛根黄酮微丸的药动学。方法:采用抗氧化效应法测定给药后不同时间点大鼠血浆中所含黄酮类成分的抗氧化能力,计算出血浆中黄酮类物质的含量,得到大鼠给药葛根黄酮后血浆中黄酮类物质的含量的变化曲线,得出微丸制剂在体内的药动学过程。结果:葛根黄酮微丸给药后的AUC为愈风宁心片的4.40倍。结论:将葛根黄酮制成微丸能够有效提高葛根中黄酮类物质的生物利用度。

葛根黄酮提取物诱导HL-60细胞凋亡调控研究

用RT-PCR技术和蛋白质免疫印迹技术,检测caspase-8和caspase-3基因转录和蛋白质翻译水平的变化,以探讨葛根黄酮提取物诱导HL-60细胞凋亡的调控途径。结果表明,50μg/mL葛根总黄酮提取物可以上调caspase-8和caspase-3基因转录和蛋白质翻译水平,且其能力分别强于葛根素和大豆甙元单体;说明葛根黄酮提取物诱导HL-60细胞凋亡可能通过经F as死亡受体和/或线粒体途径共同介导执行,葛根黄酮提取物抑制诱导凋亡能力强于葛根素和大豆甙元单体。

CO_2超临界萃取葛根总黄酮的研究

以葛根为原料,采用CO2超临界提取法提取葛根中的总黄酮。用L9(34)正交试验考查了提取温度、提取时间、料液比、萃取压力四因素对总黄酮提取率的影响。实验结果表明,在温度为50℃,料液比为280:330(g/mL),萃取压力35MPa条件下萃取2h,总黄酮的提取率为1.4572%。

微波辅助提取葛根黄酮的工艺研究

以葛根为原料,乙醇为溶剂,采用微波辅助提取葛根总黄酮。考察了溶剂体积分数、固液比、提取时间、微波功率以及提取次数对提取液葛根总黄酮含量的影响。并在单因素试验的基础上,进行4因素3水平的中心组合试验,通过响应面分析优化确定葛根总黄酮的提取工艺。结果表明,在乙醇体积分数56%、固液比1∶25、提取时间31s、微波功率539W、提取次数为2次的条件下总黄酮含量最高,模型预测值可达7.26mg/g,实际验证值为7.32mg/g。

几种中药组分对家兔体外血小板聚集作用的比较

目的:对多种活血化淤中药的有效组分抑制血小板聚集的作用进行比较。方法:以二磷酸腺苷(ADP)、血小板活化因子(PAF)和胶原为诱导剂,用Born比浊法测定六种中药有效组分对家兔体外血小板聚集的影响,比较各组分的作用强弱和特点。结果:人参皂苷、三七皂苷和红花色素对ADP、PAF和胶原诱导的血小板聚集都有明显的抑制作用,人参皂苷的抑制作用优于其它两种组分;丹参酚酸和葛根黄酮可明显抑制ADP和胶原诱导的血小板聚集,但不影响PAF引起的血小板聚集;麦冬皂苷可明显抑制胶原诱导的血小板聚集,但对ADP和PAF引起的血小板聚集无明显抑制。结论:人参皂苷抑制血小板聚集的作用最强;三七皂苷、人参皂苷和红花色素具有广谱抗血小板聚集作用;丹参酚酸、葛根黄酮及麦冬皂苷各有特点。

葛根黄酮对大鼠脑缺血再灌注损伤的保护作用

目的:探讨葛根黄酮对脑缺血再灌注损伤的保护作用。方法:采用大鼠大脑中动脉栓塞模型,研究葛根黄酮对脑缺血再灌注脑组织含水量和脑梗死体积,脑组织中SOD,MDA的影响。结果:葛根黄酮能明显降低大脑中动脉大鼠脑含水量,缩小脑梗死体积,提高SOD的活性,减少缺血再灌大鼠MDA的含量。结论:葛根黄酮具有抗自由基损伤和保护缺血脑组织的作用。

葛根多糖和黄酮综合提取工艺优化

研究热水浸提葛根多糖和黄酮综合提取的工艺路线。在单因素试验的基础上,选定料液比、提取时间及提取温度3个因素的3个水平进行中心组合试验,建立多糖和黄酮总含量的二次回归方程,进一步优化提取工艺条件,验证模型的有效性,通过响应面分析得到优化组合条件。结果表明,提取温度、提取时间对多糖得率均有显著影响,而料液比无显著影响。当提取工艺条件为提取时间2.2h、料液比1:25.2(g/mL)和提取温度98.4℃时,水提葛根多糖黄酮提取量达到极大值。此条件下多糖和黄酮总提取量预测值为29.0591%,验证值为28.9472%。

葛根总黄酮对刀豆蛋白A诱导的小鼠免疫性肝损伤保护作用及其机制的初步研究

病毒性肝炎（viral hepatitis）是常见病、多发病,通过一系列的免疫应答可引起肝细胞损伤,其中以细胞免疫为主,特别是TNF-α大量释放,可导致肝脏急性出血性坏死[1]。葛根是豆科植物野葛Pueraria lobata（Willd.）Ohwi.的干燥根,含多种黄酮类成分,具有解酒毒、降血脂等多种药理活性[2]。

葛根提取方法的比较研究及其工艺条件优化

采用水提法、回流法、渗漉法、索氏提取法、微波辅助萃取法、超声提取法等不同的方法提取葛根药材,以干浸膏得率、总黄酮得率及葛根素粗品得率为考察指标,对6种提取方法进行比较,并对其中一种最优方法进行工艺优化。结果表明,传统水提法提取葛根药材的效果最好。通过正交试验获得最佳提取工艺条件为8倍量溶剂,提取3次,每次1.5 h,其中溶剂倍量和提取次数为显著影响因素。水提法提取葛根药材,方法简便,有效成分的提取率高。

不同干燥方法对葛根黄酮含量的影响研究

目的:研究不同干燥方法对葛根总黄酮及葛根素、大豆苷、大豆素、染料木苷、染料木素含量的影响。方法:采用分光光度法和高效液相色谱法测定热风干燥、真空干燥、冷冻干燥法干制葛根粉中葛根总黄酮、葛根素、大豆苷、大豆素、染料木苷、染料木素含量,研究干燥方法对葛根黄酮含量变化的影响规律,探寻最佳葛根干燥方法。结果:冷冻干燥葛根总黄酮含量最高,热风干燥葛根总黄酮含量最低,冷冻干燥、真空干燥和低温热风干燥葛根总黄酮含量无显著差异;热风干燥中,随着干燥温度升高,葛根总黄酮、葛根素、染料木苷、大豆素含量降低,染料木素损失殆尽,大豆苷含量增加;冷冻干燥、真空干燥对葛根素、大豆苷、染料木素含量影响差异显著,对大豆素、染料木苷含量影响差异不显著。结论:葛根干燥时,考虑干燥成本宜采用低温热风干燥;考虑葛根内在品质宜采用真空干燥,冷冻干燥对葛根内在品质提高有限。

葛根总黄酮经鼻与口服给药的药代动力学研究

目的:考察葛根黄酮滴鼻剂经鼻腔给药后在兔体内的药代动力学过程,并与口服给药途径进行对比研究。方法:10只新西兰大白兔随机分为两组,分别采用经鼻腔给药和口服给药(葛根黄酮106.4mg/kg),用HPLC检测,DAS2.0软件计算两种给药途径的生物利用度。结果:经鼻给药和口服给药的主要药动学参数分别为AUC(0-∞)1(30.55±4.93)mg/(L.h),(6.90±2.76)mg/(L.h);Tmax1=(0.90±0.14)h,(0.63±0.34)h;Cmax1=(11.27±1.66)mg/L,(1.68±0.84)mg/L。相对生物利用度F=442.8%。结论:葛根总黄酮滴鼻剂在兔体内的吸收好,生物利用度较高。