ABSTRACT
Objective To develop an HPLC-UV-DPPH method to compare anti-oxidants of Rehmanniae Radix and Rehmanniae Radix Praeparata sample from different manufactories and to provide an effective method for the processing and quality control of traditional Chinese medicine. Methods HPLC in HPLC-UV-DPPH system was performed on Aglient Extend C18 (250 mm × 4.6 mm, 5 μm) column with gradient elution of acetonitrile-0.1% acetic acid at the flow rate of 1.0 mL/min, and the detection wavelength was at 334 nm. The column temperature was 30 ℃. Flow rate of DPPH solution is 0.5 mL/min, and detection wavelength was set at 517 nm. The total activities of the samples and the contribution rate of each component to the total activity were evaluated by the “quantity-effect” research idea, and verbascoside was regarded as a positive reference. The main anti-oxidants in original and processed herbs were identified by HPLC-FT-MS and were compared. Results The detection of HPLC-UV-DPPH method showed that there were nine anti-oxidants in Rehmanniae Radix extract, while 13 anti-oxidants were found in Rehmanniae Radix Praeparata. There were eight common anti-oxidants in the two herbs. The anti-oxidants were obviously different before and after Rehmanniae Radix processed. The activities of the antioxidants in different samples were markedly different. Anti-oxidants with higher contributions were mussaenosidic acid, echinacoside, jionoside A1/A2, verbascoside, and isoverbascoside, respectively. Conclusion The HPLC-UV-DPPH method is stable, sensitive, reproducible, and suitable for rapid screening of anti-oxidants and quality evaluation of Rehmanniae Radix and Rehmannia Radix Praeparata.
ABSTRACT
OBJECTIVE:To optimize the extraction technology of Tibetan medicine Pedicularis kansuensis and compare con-tent of verbascoside and isoverbascoside differences in P. kansuensis from various habitats. METHODS:Using verbascoside and iso-verbascoside and dry paste yield as comprehensive evaluation indexes,single factor test and orthogonal test were used to investigate the extraction solvent,solvent dosage,extraction time and times to optimize extraction technology,and the verification test was conducted. Contents of the 2 constituents verbascoside and isoverbascoside in P. kansuensis from Gansu,Qinghai and Sichuan were compared. RESULTS:The optimal extraction technology was as follows as 8-fold 50% ethanol,extraction for 3 times,90 min each time. The verification results showed that the average contents of verbascoside and isoverbascoside were 3.49%(RSD=1.28%,n=3),1.26%(RSD=1.32%,n=3),and average dry paste yields were 37.99%(RSD=1.97%,n=3). The contents of verbascoside and isoverbascoside in P. kansuensis from Qinghai were relatively higher. CONCLUSIONS:Optimized extraction tech-nology is reasonable,stable,feasible;the contents of index constituents in P. kansuensis from different habitats have certain differ-ences. The study can provide scientific evidence for the development and utilization of extraction,and the in-depth study of quality evaluation for medicinal material.
ABSTRACT
Objective: To establish a preparation method for verbascoside and isoverbascoside with high purity from Pediculariskansuensis. Methods: With the contents of verbascoside and isoverbascoside as indexes, static and dynamic adsorption-desorption were used to select the best macroporous resin from 01A1, D101, HPD100, AB-8, XAD-6, DM130, DM-301, DM-201, YWD06B, and YWD06C. The purification technology parameters of total phenylethanoid glycosides (PhGs) from P. kansuensis were optimized by selected macroporous resin. Medium pressure column chromatography was further used to purify verbascoside and isoverbascoside. The chemical structures were identified on the basis of the spectral data. Results: D101 type resin showed the best purifying profile, its optimum technology conditions were as follows: Sample injection concentration was 20 mg/mL, sample flow rate was 3 BV/h, then washing off the impurity with 3 BV deionized water, and being eluted by 5 BV 50% ethanol with the desorption rate at 2 BV/h. The 50% ethanol fraction was evaporated and dried with cry desiccation to obtain the total PhGs. The contents of verbascoside and isoverbascoside in total PhGs were 42.29% and 28.51%, respectively. After purified by medium pressure column chromatography, the contents of prepared verbascoside and isoverbascoside reached 98.3% and 99.2%, respectively. Conclusion: This method can be used for the large-scale preparation of verbascoside and isoverbascoside with high purity, which is rapid, simple, and practicable with high efficiency.