Dissertation > Excellent graduate degree dissertation topics show

Extraction Technology, Quality Standards and Preliminary Pharmacodynamic Study of Rhynchophylline

Author: LiuMing
Tutor: TangJianLin
School: Third Military Medical University
Course: Pharmaceutical Analysis
Keywords: rhynchophylline qualitative and quantitative extraction and purification quality standards anxiolytic effect
CLC: R285
Type: Master's thesis
Year: 2011
Downloads: 194
Quote: 0
Read: Download Dissertation

Abstract

Modern pharmacological studies have shown that Uncaria indole alkaloids which are the effective composition of traditional Chinese medicine–Uncaria, not noly had antihypertension and anti-epileptic effect, but also had anti-anxiety effect. How to get the active ingredients of Uncaria alkaloid from Uncaria is the key to further research. Current extraction technology is mainly for crude extracts and total alkaloids of Uncaria, but few for the extraction of active ingredients. To determine the optimal extraction and purification technology, establish quality standards and conduct a preliminary evaluation of the anxiolytic efficacy of rhynchophylline, the extraction, quality standards, and anti-anxiety effect were investigated by this subject.1. Qualitative and quantitative methodsTLC method was established to identify rhynchophylline. Acetone: petroleum ether: ammonia（1:2:0.2） was used as Developing agent and rhynchophylline can be separated from other alkaloids and impurities on the GF254 silica gel plates （size: thickness 0.2-0.25mm, 25×40mm） in a few minutes. HPLC method was established to quantify rhynchophylline. Chromatography was performed on a Platisil ODS column （150×4.6mm, 5μm）. Gradient elution was employed with a mobile phase consisting of acetonitrile （solution A） and potassium dihydrogen phosphate buffer（0.01M,pH8.0 adjusted by KOH, solution B） as follows:A:B from 30:70 to 60:40 between 0 and 40 min. The flow rate of the mobile phase was 1.0 mL/min and the column was maintained at 30℃. The detector was monitored at 245 nm and the injection volume was 20μL. The calibration curve was linear among the concentration range of 0.25-64.0μg/mL （Y=3.64×10⁴X-2.13×10⁴, r=0.9995） and the relative recovery was between 95.95%-114.4%. The determination RSD was 6.50% and the retention time RSD was 0.69% of the reproducibility test. The assay method can be used for the determination of rhynchophylline. 2. Extraction and purificationThe optimum extraction technology of crude extracts was established through single factor experiment and L₉（3）³ orthogonal experiment in the first step and the the extraction rate of crude extracts of herbs was 7.54%. The extraction conditions was with 80% ethanol as solvent, medicinal quality and solvent volume ratio is 1:5, cold soakunder 4℃for 12 h and ultrasound under 50 Hz for 1 h. A silica gel column chromatography method was established in the second step using acetone: petroleum ether: ammonia（1:2:0.2） as eluent, the quantity of sample and silica ratio was 1:40. The fraction of rhynchophylline was collected, extracted by 2% hydrochloric acid and chloroform and washed by water. The product was obtained after freeze-dried, the purity of rhynchophylline was above 90%, and the extraction rate came to 0.201‰.3. Quality standards and preliminary stabilityThe structure and molecular weight of rhynchophylline prepared by the new technology were confirmed by UV, MS,and NMR methods. The arsenic salt, heavy metals, and residual solvent were inspected and the results meet the standards of pharmacopoeia 2010 edition. Rhynchophylline content did not change significantly under conditions of high temperature, high humidity and bright light within 10 days. The stability of rhynchophylline in strong acid and alkali media were investigated and the results showed that rhynchophylline was stable in 2%, 4%, 8% HCl within 24 h and in 0.1 mol/L NaOH within 8 h at room temperature.4. Preliminary anxiolytic pharmacodynamicsThe elevated plus maze and open field test for both rats and mice, wearing light and dark box test for mice were put on to investigate the anxiolytic effects of different doses of rhynchophylline. Normal control animals were given 20% DMSO. 5mg/kg diazepam was used as positive control drugs. Results showed that 80 mg/kg rhynchophylline had significant anxiolytic effects in the elevated plus maze and wearing light and dark box test for mice and open field test for rats. The remaining doses of rhynchophylline and total alkaloids in some models showed varying degrees of anti-anxiety effects.

Extraction Technology, Quality Standards and Preliminary Pharmacodynamic Study of Rhynchophylline

Abstract

Related Dissertations