Simultaneous determination of naphthalene and anthraquinone derivatives in Rumex nepalensis Spreng. roots by HPLC: comparison of different extraction methods and validation

Introduction – Rumex nepalensis contains mainly anthraquinone and naphthalene derivatives. Although HPLC methods have been reported for the analysis of anthraquinones, neither a phytochemical analysis of Rumex species nor the simultaneous determination of anthraquinone and naphthalene derivatives in other samples has been reported so far. Objective – To develop and validate a HPLC method for the simultaneous determination of anthraquinone and naphthalene derivatives in R. nepalensis roots. Methodology – Anthraquinones and naphthalenes were extracted from R. nepalensis roots by three methods (reflux, ultrasonication and pressurized liquid extraction) using methanol. Separation was achieved on an RP C₁₈ column with a gradient mobile phase consisting of 0.05% orthophosphoric acid in water (solvent A) and methanol (solvent B) using a UV detector (254 nm). Results – Small differences were observed in the contents of anthraquinone and naphthalene derivatives extracted by the three methods. Chrysophanol‐8‐O‐β‐D‐glucopyranoside and nepodin were detected as major constituents. The method showed a good linearity (r² > 0.9992), high precision (RSD < 5%) and a good recovery (97–105%) of the compounds. The lowest detection limit was found to be 0.97 ng and the method was found to be robust. Conclusion – Reflux and ultrasonication were found to be the best suited methods for the extraction of glycosides and aglycones, respectively. The developed and validated HPLC method is simple, precise and accurate; and can hence be recommended as the method of choice for the analysis of anthraquinones and naphthalenes in R. nepalensis and other Rumex species for both quality control as well as routine analytical purposes. Copyright © 2010 John Wiley & Sons, Ltd.     

逆阿落中的黄酮化合物

从藏药逆阿落(Polygonum periginatoris Pauls)的乙酸乙酯提取物中分离得到四个黄酮化合物,通过波谱分析及化学方法鉴定了它们的结构,其中5,4’-二甲氧基．6,7-二氧亚甲基黄酮-3-0-β-芹糖(1→6)-β-葡萄糖甙(Periginatorine I)为新化合物,其余三个已知黄酮类化合物为首次从该植物中分离得到。     

铝胁迫对蓼科植物生长和光合、蒸腾特性的影响

采用水培试验,设置5种铝处理浓度,研究了铝对3种蓼科植物酸模叶蓼、杠板归和辣蓼叶片光合、蒸腾和叶绿素荧光参数的影响。结果表明,高铝处理(400μmol.L-1)显著抑制3种蓼科植物地上部和根系生长,并且导致3种蓼科植物叶片叶绿素含量、Chla/Chlb、净光合速率(Pn)、水分利用效率(WUE)、PSII光合电子传递量子效率(φPSII)和光化学猝灭系数(qP)显著下降。中低铝处理(25~100μmol.L-1)时,与对照相比,酸模叶蓼生物量显著增加,杠板归显著减少,辣蓼先增加后减少。其中,酸模叶蓼和辣蓼叶绿素含量、Chla/Chlb、Pn、蒸腾速率(Tr)、胞间CO2浓度(Ci)、PSII最大光化学效率(Fv/Fm)、qP均未发生显著变化,但辣蓼WUE、φPSII和非光化学猝灭系数(NPQ)显著下降,酸模叶蓼无显著变化;而杠板归除Ci、Fv/Fm外,其余叶片光合、蒸腾及叶绿素荧光参数均出现显著下降。上述结果表明,酸模叶蓼在中低铝处理条件下可通过保持较高的叶绿素含量、Chla/Chlb、WUE、Pn、PSII反应中心光化学反应效率以及提高非辐射能量耗散来增强其对铝的耐性。     

六个不同类型荞麦花花粉粒形态的电镜观察比较研究

对二倍体甜荞长花柱类型 (ES2 s)、二倍体甜荞短花柱类型 (ES2 S)、四倍体甜荞长花柱类型 (ES4s)、四倍体甜荞短花柱类型 (ES4S)、四倍体有翅细野荞 (GR4HI)、四倍体无翅细野荞 (GR4HO)等 6个不同荞麦类型花的花粉形态学进行了电镜观察。结果表明 :这些荞麦类型的花粉粒都是椭圆形 ,都有网状纹饰、3孔沟等特征。二倍体甜荞染色体加倍后形成的四倍体甜荞 ,相对于二倍体甜荞而言 ,花粉粒显著增大和明显变圆。无论二倍体还是四倍体甜荞 ,其长花柱型花的花粉粒都比其对应短花柱型花的花粉粒要小。尽管四倍体甜荞和四倍体细野荞在染色体数目和倍性上一样 ,但是它们在花粉粒的大小上有显著差异。四倍体细野荞有翅类型和无翅类型的花粉粒大小和形态差异不显著