| Rhodiola species have been used in China for thousands of years.Among Rhodiola species,Rhodiola crenulata is one of the most commonly used species and has been recorded in Chinese Pharmacopoeia（2005 Edition）.In this thesis,the chemical constituents,quality control methods and the pharmacokinetics of Rhodiola crenulate were investigated in detail.The chemical constituents of Rhodiola crenulate were systematically studied and 10 compounds were purified with silica gel,polyamide,sephadex LH-20 column chromatography and pre-HPLC methods.Utilizing chemical and spectroscopic methods （UV,NMR,MS）,the structures of 10 compounds were fully characterized as kaempferol, kaempferol-7,O-α-L-rhamnoside,gallic acid ethyl ester,tyrosol,salidroside, herbacetin-7-O-α-L-rhamnoside,gallic acid,crenulatin,β-sitosterol and dancosterol.These compounds were suitable as standard substances for quantitative and pharmacokinetic purposes.The method of HPLC fingerprint analysis was established for the quality control of Rhodiola crenulate.All of the 14 samples were selected to develop the common recognition pattern and to generate the representative characteristic chromatograms.The similarity was calculated.Based on the results of similarity,the evaluation criterion for quality control of the herb was established.HPLC-UV quantitative analysis methods were established for assessing the quality of Rhodiola crenulate.Under the gradient elution mode,an HPLC-UV method was developed for the simultaneous quantification of those four phenolic compounds:gallic acid, salidroside,tyrosol and gallic acid ethyl ester.Under the isocratic elution mode,an HPLC-UV method was developed for the simultaneous quantification of those three flavonoids constituents:herbacetin-7-O-α-L-rhamnoside,kaempferol-7-O-α-L-rhamnoside and kaempferol.The methods were rapid,accurate and could be readily utilized as quality control methods of Rhodiola crenulate. A simple,rapid and sensitive liquid chromatography-mass spectrometry（LC-MS） method was developed for the quantification of salidroside in rat plasma and the study of its pharmacokinetics after oral administration of 15 g·kg-1Rhodiola crenulata extract and 46.2 mg-kg-1of salidroside to Wistar rats respectively.A 200μL plasma sample was extracted by acetonitrile and performed on Kromasil C18column（150 mm×4.6 mm,5μm） with the mobile phase of acetonitrile-water（11:89）within a run time of 8 min.The analyte was monitored with electrospray ionization（ESI）by selected ion monitoring（SIM） mode.The target ions were m/z 299.20 for salidroside and m/z 150.00 for internal standard （IS）acetaminophen.A good linear relationship was obtained over the range of 100～20000 ng.mL-1and the validated method was successfully applied for the pharmacokinetic study of salidroside in rat.The T1/2were 0.6±0.2 h and 0.7±0.3 h respectively.The Cmaxwere 3386±2138 ng·mL-1and 8719±532.9 ng·mL-1respectively.The TmaxWere 7.9±4.4 h and 2.8±0.7 h respectively.The AUC0-twere 16146±6558 ng·h·mL-1and 23707±2612 ng·h·mL-1respectively.The AUC0-∞were 18599±6529 ng·h·mL-1and 23965±3127 ng·h·mL-1respectively.There are significant differences among the pharmacokinetic parameters.Salidroside and tyrosol were qualitatively analyzed by HPLC-MS in different bio-matrices,such as urine,feces and all tissues in Wistar rats.The absorption,distribution and excretion of salidroside and tyrosol inWistat rats after oral administration of Rhodiola crenulata extract were preliminarily investigated.The results indicated that after oral administration of Rhodiola crenulata extract,4.78%of administration dosage as salidroside were detected in urine and 0.43%of administration dosage as tyrosol was detected in feces;while there were no tyrosol detected in urine nor salidroside detected in feces.The contents of salidroside and tyrosol were highest in stomach,and the contents in pancreas,small intestine,uterus and ovary were higher than others,and decreased with the prolongation of time in almost all tissues.Combining the utilization of phytochemistry,pharmaceutical analysis,pharmacognosy, pharmacology and pharmacokinetics,the constituents and quality assessment standards for Rhodiola crenulata were studied,and the metabolism of this medicinal herb and its active constituents were also investigated.This research provided a beneficial exploration for the modernization of the herb. |
