[Mass Transfer Kinetics Model of Ultrasonic Extraction of Pomegranate Peel Polyphenols].

OBJECTIVE: The dynamic mathematical model of ultrasonic extraction of polyphenols from pomegranate peel was constructed with the Fick's second law as the theoretical basis. METHODS: The spherical model was selected, with mass concentrations of pomegranate peel polyphenols as the index, 50% ethanol as the extraction solvent and ultrasonic extraction as the extraction method. In different test conditions including the liquid ratio, extraction temperature and extraction time, a series of kinetic parameters were solved, such as the extraction process (k), relative raffinate rate, surface diffusion coefficient(D(S)), half life (t½) and the apparent activation energy (E(a)). RESULTS: With the extraction temperature increasing, k and D(S) were gradually increased with t½ decreasing,which indicated that the elevated temperature was favorable to the extraction of pomegranate peel polyphenols. The exponential equation of relative raffinate rate showed that the established numerical dynamics model fitted the extraction of pomegranate peel polyphenols, and the relationship between the reaction conditions and pomegranate peel polyphenols concentration was well reflected by the model. CONCLUSION: Based on the experimental results, a feasible and reliable kinetic model for ultrasonic extraction of polyphenols from pomegranate peel is established, which can be used for the optimization control of engineering magnifying production.

Hernsubanine E, a new hasubanan alkaloid from Stephania hernandifolia.

A new hasubanan alkaloid, hernsubanine E (1), as well as two known compounds p-hydroxybenzaldehyde (2) and (-)-syringaresinol (3) have been isolated from the whole plants of Stephania hernandifolia by various column chromatographic methods. Their structures were identified by physicochemical properties and spectral analyses. Compounds 2 and 3 were isolated from the genus of Stephania for the first time.

Cepharatines A-D, hasubanan-type alkaloids from Stephania cepharantha.

Four new hasubanan-type alkaloids, cepharatines A-D (1-4), were isolated from the leaves and stems of Stephania cepharantha, and their structures were elucidated by spectroscopic analysis. The structure of 1 was further confirmed by X-ray crystallographic diffraction.

[Study on the alkaloids in the stems and leaves of Stephania cepharantha (II)].

OBJECTIVE: To study the alkaloids in the stems and leaves of Stephania cepharantha Hayata. METHODS: The dried stems and leaves of Stephania cepharantha Hayata were percolated with 95% ethanol and the solvent was removed by rotary evaporation to give a concentrate, and the concentrate was extracted by petroleum ether and chloroform. Column chromatograghy on MCI CHP 20P, silica gel, Rp-18, Sephadex LH-20 and polyamide were applied for the isolation and purification of the chloroform fraction. The structures were elucidated by their physicochemical properties and spectral data. RESULTS: Five alkaloids were obtained and identified as, Stephasunoline (I) Aknadinine (II), Discretamine (III), Acutumine (IV), Sinomenine (V). CONCLUSION: Compounds I, III, IV are isolated from this plant for the first time, and compound IV is isolated from the genus for the first time.

[Study on the alkaloids in Stephania hernandifolia].

OBJECTIVE: To study the alkaloids in Stephania hernandifolia. METHODS: The dried herbs of S. hernandifolia were extracted with 95% ethanol. After removal of the solvent, the residue was first partitioned between acid water and petroleum ether, then the aqueous layer was basified and extracted with chloroform to obtain crude alkaloids. Column chromatography on silica gel, Rp-18, MCI CHP 20P, Sephadex LH-20 were applied for the isolation and purification of the crude alkaloids fraction. The structures were elucidated by their physicochemical properties and spectral data. RESULTS: Six alkaloids were obtained and identified as Cepharamine (I), l-tetrahadropalmatine (II), Plmatine (III), Stephamiersine (IV), Telitoxine (V), Daurioxoisoporphine D (VI). CONCLUSIONS: Compounds I - VI are isolated from this plant for the first time, and compounds V, VI are isolated from the plants of Stephania for the first time.

Monoterpenoid indole alkaloids from Gardneria multiflora.

Six new monoterpenoid indole alkaloids, 19(E)-9-demethoxy-16-dehydroxylchitosenine-17-O- ß-d-glucopyranoside (1), 19(E)-9,10-didemethoxy-16-dehydroxylchitosenine-17-O-ß-d-gluco-pyranoside (2), 19(E)-9,10-didemethoxy-16-dehydroxyl-11-methoxychitosenine (3), 19(E)-9,10-didemethoxy-16-dehydroxyl-11-methoxychitosenine-17-O-ß-d-glucopyranoside (4), 19(Z)-18-carboxylgardneramine (5), and 19(E)-18-demethoxygardneramine-N (4)-oxide (6), along with four known alkaloids, were isolated from Gardneria multiflora, and their structures were elucidated by spectroscopic analysis. Compounds 1, 2 and 4 are the first example of Gardneria alkaloids whose glucose units were attached to C-17. None of the compounds were cytotoxic to any of five human cancer cell lines.

[Studies on chemical constituents in spikes of Schizonepeta tenuifolia].

OBJECTIVE: To study the chemical constituents in the spikes of Schizonepeta tenuifolia. METHOD: Compounds were isolated and purified with silica gel, ODS and Sephadex LH-20 gel column chromatography, and their structures were determined by using spectroscopic analysis including MS and NMR. RESULT: Nine compounds were isolated and identified as 5, 7-dihydroxy-6, 4'-dimethoxyflavone (1), 5, 7-dihydroxy-6, 3', 4'-trimethoxyflavone (2), ursolic acid (3), 3-hydroxy-4(8)-ene-p-menthane-3(9)-lactone (4), 5, 7, 4'-trihydroxyflavone (5), 5, 4'-dihydroxy-7-methoxyflavone (6), hesperidin (7), luteolin (8) and daucesterol (9). CONCLUSION: Compounds 1, 2, 6 were first obtained from the spikes of S. tenuifolia.

[Studies on the chemical constituents in herb of Mentha haplocalyx].

OBJECTIVE: To study the chemical constituents of Mentha haplocalyx. METHOD: The chemical constituents were isolated and purified with column chromatography and the structures were elucidated by spectral analysis. RESULT: Nine compounds were obtained and identified as emodin (I), chrysophanol (II), physcione (II), benzoic acid (IV), trans-cinnamic acid (V), beta-sitosterol (VI), aloe-emodin (VII), ursolic acid (VIII) and daucosterol (IX). CONCLUSION: Compounds I, II, III, V, VII were first isolated from M. haplocalyx.

A new bufadienolide with cytotoxic activity from the Chinese traditional drug Ch'an Su.

AIM: To study the bufadienolides in the Chinese traditional drug "Ch'an Su" and their cytotoxic activity. METHOD: Various chromatographic techniques were used to isolate the constituents, and their structures were elucidated through physical and spectroscopic data. RESULTS: Twenty compounds were isolated, and eighteen were evaluated in vitro for their cytotoxic activity against A-549 and K-562 cells. CONCLUSION: Compound 1 (bufalin 3ß-acrylic ester) was a new bufadienolide and exhibited the most potent activity against the two tumor cell lines with IC50 values of 7.16 and 6.83 nmol · L(-1). The relationships between structure and activity are discussed.