常山碱稳定性及其降解动力学研究

对常山碱的稳定性及其降解动力学进行研究。结果表明,24 h内流动相作溶剂时,常山碱含量仅降低1%,但在水、甲醇、50%甲醇及10%乙腈溶液中其含量降低为起始含量的90%。当溶液pH介于3~7时,24 h内常山碱的保留率在98%以上,但在碱性溶液中(pH 9.0)含量降低约12%。温度越高,常山碱稳定性越差,40~80℃放置10 h后,常山碱降为起始含量的60%左右,但在20℃下放置10 h,其含量仅降低约5%;40,60℃放置10 h,常山碱主要转化为异常山碱,二者的总含量较起始总含量基本不变,但是80℃下放置10 h,常山碱和异常山碱的总含量降低为起始总含量的83.33%,说明高温下常山碱结构发生了彻底改变,而不仅仅是异构化为异常山碱。光照对常山碱稳定性影响显著,强光照射108 h,常山碱质量分数较起始含量降低23%左右,但在避光和自然光条件下,其含量仅降低10%左右。无论在人工胃液(pH 1.4)还是人工肠液(pH6.8)中,放置10 h后,常山碱质量分数降低均小于5%。常山碱固体在高温(60℃)、高湿[(75±1)%]和强光(3 000 lx)照射下放置10 d后,其含量分别减少0.27%,7.6%,5.39%。常山碱在水、甲醇、50%甲醇和10%乙腈溶剂中、碱性溶液、不同光照和不同温度(20,40℃)下的降解基本符合化学动力学一级反应。因此,无论是常山碱的制备纯化还是相关制剂的生产,都应在偏酸性溶液,低温、避光条件下快速操作完成,而常山碱固体则应在干燥、避光条件下保存。     

Comparison of antimalarial activity of the alkaloidal fraction of Hydrangea macrophylla var. Otaksa leaves with the hot-water extract in ICR mice infected with Plasmodium yoelii 17 XL

The antimalarial activity of the fractions isolated from the leaves of Hydrangea macrophylla Seringe var. Otaksa Makino was evaluated against Plasmodium yoelii 17 XL in mice. Four different fractions were prepared in the usual manner to obtain an alkaloid fraction. All mice treated with the fraction containing febrifugine and isofebrifugine mixture at 1 mg/kg twice a day for 5 consecutive days survived during the experiment, and the change of mean parasitemia level showed almost the same pattern as that from mice treated with the hot-water extract of the same plant leaves. Activity of this fraction, however, was markedly reduced compared with the hot-water extract. Furthermore, no antimalarial activity was shown in the hotwater extract from H. macrophylla var. Otaksa roots or Dichroa febrifuga Lour. leaves.     

常山叶中一种新的喹唑酮生物碱

从常山中分离得到一种新的生物碱，命名为新常山碱，还分离得到已知的常山碱、异常山碱、香豆素，双氢黄酮和香草醛。新生物碱的结构通过波谱解析和与自常山碱的半合成产品对照来确定。     

Different responses of three rodent Plasmodia species,Plasmodium yoelii 17XL,P. berghei NK65 and P. chabaudi AS on treatment with febrifugine and isofebrifugine mixture from Hydrangea macrophylla var. Otaksa leaf in ICR mice

The antimalarial activity of Hydrangea macrophylla var. Otaksa alkaloids was evaluated against Plasmodium yoelii 17XL, P. berghei NK65 and P. chabaudi AS in ICR mice. For trials in P. yoelii 17XL or P. chabaudi AS infections, mice were infected intraperitoneally with 10(5), 10(6) and 10(7) parasitized erythrocytes, respectively, and in P. berghei NK65 infections, mice were infected intraperitoneally with 10(3), 10(4) and 10(5) parasitized erythrocytes, respectively. Three days after injection, mice were orally given febrifugine and isofebrifugine mixture at 1 mg/kg in the treated group and 0.5% cremophor EL solution in the untreated, infected one, respectively, twice a day for 5 consecutive days. In P. yoelii 17XL infections, mice in all the non-treated controls died from 5 to 9 dpi with a gradual body weight loss and increasing parasitemias. In the treated groups, the mouse body weight gradually decreased after the end of administration but turned to increase in several days, and except one mouse in the group given 10(6) parasitized erythrocytes, other mice survived during the experiment. Mice given orally the mixture showed low parasitemia levels during administration. Following a transient recrudescence of malaria parasites in the bloodstream of treated mice, no parasites could be detected by a microscopic examination. In P. berghei NK65 infections, mice in all the non-treated controls died from 7 to 12 dpi with a gradual body weight loss and increasing parasitemias. In the treated groups, the body weight gradually decreased from 11 dpi and all mice died from 12 to 30 dpi. During a mixture administration all mice showed slight suppression of multiplication of malaria parasites. After the end of administration, however, malaria parasites increased in the bloodstream of the treated mice and all mice died. In P. chabaudi AS infections, there were two different patterns in the course of infection; lethal infection or recovery in both the non-treated control and treated groups. In the non-treated and treated groups, mice showed a gradual body weight loss. But the body weights of survivals in both groups turned to increase in several days. Mice in control and treated groups showed as the same profile in the changes of parasitemia. In the non-treated controls, after a transient peak parasitemia malaria parasites in the bloodstream of survivals could not be detected by a microscopic examination. During a mixture administration, all mice showed suppression of multiplication of malaria parasites. After the end of medication, some mice died with increasing parasitemia. After a transient recrudescence, however, malaria parasites in the bloodstream of survivals could not be detected by a microscopic examination.     

Combination effects of chloroquine with the febrifugine and isofebrifugine mixture against a blood-induced infection with chloroquine-resistant Plasmodium berghei NK65 in ICR mice

The combination effects of chloroquine with a mixture of febrifugine and isofebrifugine were evaluated against a blood-induced infection with chloroquine-resistant P. berghei NK65 in ICR mice. Mice in the untreated control showed a progressively increasing parasitemia leading to mouse death. A two-day dosage of 20 mg base/kg of chloroquine alone showed little effect against P. berghei NK65 infection, and all mice died from day 13 to 14 with an increasing parasitemia. A four-day dosage of 1 mg/kg of the febrifugine and isofebrifugine mixture alone showed a little antimalarial activity, but all mice died from day 19 to 27 with an increasing parasitemia. On the other hand, mice treated with chloroquine plus alkaloids survived during the experiment. All mice treated with chloroquine alone or the alkaloid mixture alone showed low parasitemia levels during a drug administration and following a few days, but then malaria parasites increased in the bloodstream of the treated mice until death. On the other hand, malaria parasites in the mice given chloroquine plus alkaloids decreased on day 6 and then were not detected by a microscopic examination during observation period.     

常山和常山碱的药理作用及减毒研究进展

常山Dichroa febrifuga Lour.为涌吐中药,亦具截疟药效。历代古籍、近现代临床及药理研究结果均表明常山及活性成分常山碱有良好的抗疟作用,同时也发现常山治疗疟疾时存在严重的消化系统毒性,尤其易造成呕吐等不良反应。为促进常山及常山碱的安全合理应用,近现代医药工作者从中医药理论、药理作用、化学成分等多个角度进行了大量的探索。对常山的主要药理作用、作用机制及减毒相关研究（炮制减毒、相畏配伍、成分联用、结构修饰）进行系统综述,以期为常山的安全合理用药及进一步开发提供参考。     

核磁共振氢谱内标法测定常山碱的绝对含量

建立测定常山碱绝对含量的核磁共振氢谱定量分析方法。采用Bruker Ascend 600 MHz超导核磁共振仪,在298 K下,以氘代二甲基亚砜为溶剂,对苯二酚为内标,在频率600 MHz,谱宽7 211 Hz,脉冲宽度（P1）9.70μs,zg30脉冲序列,扫描次数（NS）32次,弛豫时间（Dl）2 s的条件下采集常山碱样品的氢谱。以化学位移在δ7.71的常山碱双峰和化学位移在δ6.55的对苯二酚的单峰作为定量峰,将样品与内标选定峰的峰面积比对其质量比回归得到标准曲线方程为Y=0.083 3X＋0.008 6,r为0.999 6。常山碱的线性范围为2.17-17.07 g·L^-1,精密度试验RSD为0.78%（n=6）,重复性试验RSD为1.2%（n=6）,测得3批常山碱样品量分别为94.91%,95.09%和95.52%。采用高效液相色谱法测得常山碱的含量为96.44%,二者的相对误差为1.27%。结果表明,核磁共振氢谱内标法可用于常山碱绝对含量的测定。     

常山中常山碱和异常山碱的同步测定研究

建立常山中常山碱和异常山碱HPLC同步测定方法,并在此基础上探讨一测多评模式用于这2种生物碱测定的可行性。采用十八烷基键合硅胶色谱柱进行分离,乙腈-水-冰醋酸-三乙胺(9∶91∶0.36∶0.745)为流动相,检测波长225 nm,流速1.0 m L·min~(-1),柱温30℃。结果表明,常山碱和异常山碱分别在10.7~426 ng,10.6~424 ng线性关系良好,平均加样回收率分别为98.33%,100.4%,RSD分别为2.7%,1.8%。在此基础上,以常山碱为内参物,建立了异常山碱对常山碱的相对校正因子与相对保留值。采用一测多评质量评价模式,经一系列方法学考察,最终实现在同一色谱条件下,仅采用常山碱1个对照品就能同时对常山碱和异常山碱2个活性成分进行同步测定。研究结果为一测多评模式在同分异构体测定中的应用起到示范作用。     

中药常山中常山碱和异常山碱的含量测定

 目的 建立高效液相色谱法同时测定中药常山中常山碱和异常山碱总含量的测定方法。方法 采用HPLC测定常山药材和饮片中常山碱和异常山碱的总含量。色谱柱：Kromasil C₁₈(4.6 mm×250 mm,5 μm;流动相：乙腈-水-冰醋酸-三乙胺(9∶91∶0.3∶0.745,冰醋酸调pH值至5.2～6.2之间;流速：1 mL·min-1;检测波长：225 nm;柱温：30 ℃。外标一点法定量。结果 常山碱和异常山碱的混合物在0.021～2.18 μg内呈良好线性关系,方法回收率介于95.16％ ～103.97％之间,回收率的RSD值为3.28％。结论 本法简便、快捷、准确,可用于常山药材及饮片中常山碱和异常山碱的含量测定。