AIMTo establish a suitable condition for extraction of phenylalanine (Phe), 5-hydroxytryptophan (5-OH-Trp) and four diastereomeric salts, (1R,2S)-ephedrine- (2S,3S)-tartaric acid, (1R,2S)-ephedrine-(2R,3R)-tartaric acid, (1S,2S)-pseudoephedrine-(2S,3S)-tartaric acid, (1S,2S)-pseudoephedrine- (2R,3R)-tartaric acid in supercritical fluid extraction and to assess the solubilities of Phe, 5-OH-Trp and the four diastereomeric salts in CO2.

METHODSSingle-pass method and HPCE.

RESULTSThe solubilities of Phe, 5-OH-Trp and the four diastereomeric salts in CO2 were determined over temperature and pressure ranges of 25-50 degrees C and 6.32-34.03 MPa respectively. The experimental results showed that the solubilities of Phe, 5-OH-Trp and the four diastereomeric salts do not increase with density of CO2. There existed a maximum in the critical region of CO2.

CONCLUSIONThe dramatically high solubilities in the pressure of 6.32-7.78 MPa show a critical behavior, which can be explained by critical characteristic through thermodynamics analysis. The results suggest that the separation of Phe, 5-OH-Trp and the four diastereomeric salts is more efficient in critical region of CO2.

5-Hydroxytryptophan ; chemistry ; Ephedrine ; chemistry ; Phenylalanine ; chemistry ; Pressure ; Solubility ; Stereoisomerism ; Tartrates ; chemistry ; Temperature

AIM: To investigate the chemical constituents of the roots of Polygala sibirica L. (Polygalaceae) METHOD: The isolation was performed by solvent extraction and various chromatographic techniques, including silica gel, Sephadex LH-20, ODS, semi-preparative HPLC, and preparative TLC. The chemical structures were elucidated based on extensive spectroscopic analysis, including HR-ESI-MS and 1D- and 2D-NMR spectroscopic data. RESULTS: A total of sixteen compounds, including five xanthones (5, 7-10), five saccharide esters (1, 3, 4, 12, 13), two flavonoids (14, 16), two triterpenoids (11, 15), one phenylpropanoid (6), and one benzophenone glycoside (2) were isolated. Their structures were determined as sibiricose A7 (1), sibiriphenone A (2), polygalatenoside A (3), polygalatenoside C (4), lancerin (5), 3, 4, 5-trimethoxycinnamic acid (6), 6-hydroxy-1, 2, 3, 7-tetramethoxyxanthone (7), 1, 3, 7-trihydroxy-2-methoxyxanthone (8), onjixanthone II (9), 1, 2, 3, 6, 7-pentamethoxyxanthone (10), presenegenin (11), 3'-O-3, 4, 5-trimethoxycinnamoyl-6-O-4-methoxy benzoyl sucrose (12), tenuifoliside C (13), 5, 3'-dihydroxy-7, 4'-dimethoxyflavonol-3-O-β-D-glucopyranoside (14), tenuifolin (15), and rhamnetin 3-O-β-D-glucopyranoside (16). CONCLUSION Compounds 1 and 2 are two new compounds from P. sibirica.
Benzophenones ; chemistry ; isolation & purification ; Coumaric Acids ; chemistry ; isolation & purification ; Glucosides ; chemistry ; isolation & purification ; Molecular Structure ; Plant Extracts ; chemistry ; Plant Roots ; chemistry ; Polygala ; chemistry ; Triterpenes ; chemistry ; isolation & purification ; Xanthones ; chemistry ; isolation & purification