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This study focused on the preparation procedures and quantitative analysis of alkaline hydrolysis products of total saponins in Radix Polygala{ AHP). Moreover, this study also tested the protective effects on nerve cells in vitro of AHP, which provided scientific evidences for exploitation of anti-AD medicines from AHP.The technology parameters for alkaline hydrolysis were researched, by taking pH value, temperature and hydrolysis time as investigated factors, the contents of tenuifolin as index, TLC and HPLC as methods. The results showed that alkaline hydrolysis was most efficient under the optimal conditions which pH=14, temperature 100℃and hydrolyzing 4h. Then the alkaline hydrolysis solution was isolated and purified by macroporous resin absorption column, eluting first with the distilled water and then 95% alcohol. Finally AHP was obtained.The main chemical constituents of AHP were isolated and purified by repeated column chromatography, TLC knowledge and recrystallization. And all the structures were identified on the basis of physicochemical and spectrometric characteristies (ESI-MS,’H-NMR and 13C-NMR). As a result, tenuifolin, fallaxsaponin,3,4,5 trimethoxycinnamic acid(TMCA), p-methoxycinnamic acid(PMCA) and cinnamic acid(CA) were isolated from AHP.Afterwards, taking tenuifolin, fallaxsaponin, TMCA and PMCA as reference substance, the contents of the main chemical constituents of AHP were determined by HPLC. And a quantitative method was developed for the determination, such as linear range, precision, repeatability, stability and average recovery. The results indicated that the contents of each constituents were as follow, tenuifolin 14.9%, fallaxsaponin 19.7%, TMCA 24.7%, and PMCA 7.7%, respectively. A total of 8 samples, alkaline hydrolysis products(AHP), total saponins(TS), oligosaccharide esters(OE), tenuifolin, fallaxsaponin, TMCA, PMCA and CA, were subjected to activity screening in vitro with SH-SY5Y cells and PC 12 cells, which were induced by 4 injury models such as H2O2, Aβ25-35, Corticosterone and Glutamic acid. And the result suggested:> For the SH-SY5Y and PC 12 normal cells, AHP, TS, tenuifolin and fallaxsaponin expressed function of helping the cells to propagate;> For the H2O2-induced SH-SY5Y cells, AHP, TS, tenuifolin and fallaxsaponin showed nerve cells protection activity;> For the Aβ25-35-induced PC 12 cells, AHP and TS showed nerve cells protection activity;> For the Corticosterone-induced PC 12 cells, TS and OE showed nerve cells protection activity;> For the Glutamic acid-induced PC 12 cells, AHP, TS, tenuifolin and fallaxsaponin showed nerve cells protection activity.In view of the anti-AD activity of TS, this study was conducted to use Ellman method to screen the anti-acetylcholinesterase activity of 8 samples mentioned above. The results showed that AHP and TS expressed positive anti-acetylcholinesterase activity.In addition, advances in the present research of the chemical constituents and pharmacologic activities of Polygala were reviewed, which provided a reference to further development and exploitation of Polygala.
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