[Screening of G-quadruplex ligands from Macleaya cordata extract by contrast ultrafiltration with liquid chromatography-mass spectrometry and molecular docking].

G-quadruplex DNA has become an important target for tumor therapy and anti-tumor development. Modern pharmacology has proved that Macleaya cordata has anti-inflammatory, antibacterial, anti-tumor and other pharmacological effects. Affinity ultrafiltration method can screen active ingredients from compounds rapidly, but G-quadruplex DNA ligands are difficult to dissociate, which is a key step in conventional ultrafiltration method. In this paper, the filtrates after ultrafiltration were determined by HPLC-MS in substitution. The peaks with 20% reduction of MS response from the incubation vs control were considered to be ligand components to G-quadruplex. Two of the peaks with the relative abundance above 30% were identified as sanguinarine(SAN) and chelerine(CHE). Their circular dichroism conformations further proved that SAN and CHE are active ligands of HT4. In addition, another two gradients with high relative abundance were identified as protopine(PRO) and allpcryprotopine(ALL). The binding rate of SAN, CHE, PRO and ALL was calculated according to the HPLC-MS results, and the results showed a consistency with that of the molecular docking method. The proposed method can be used to screen active components from mixture.

Four Pentasaccharide Resin Glycosides from Argyreia acuta.

Four pentasaccharide resin glycosides, acutacoside F-I (1-4), were isolated from the aerial parts of Argyreia acuta. These compounds were characterized as a group of macrolactones of operculinic acid A, and their lactonization site of 11S-hydroxyhexadecanoic acid was esterified at the second saccharide moiety (Rhamnose) at C-2. The absolute configuration of the aglycone was S. Their structures were elucidated by established spectroscopic and chemical methods.

Three new resin glycosides compounds from Argyreia acuta and their α-glucosidase inhibitory activity.

Three new phenolic compounds, acutacoside C (1), acutacoside D (2) and acutacoside E (3) were isolated from the aerial part of Argyreia acuta. The oligosaccharide chain was composed of two glucoses and three rhamnoses, and the aglycone was (11S)-hydroxyhexadecanoic acid (jalapinolic acid). The core of the three compounds was operculinic acid B, which was rare in resin glycosides. Their structures were established by a combination of spectroscopic and chemical methods. Compounds 1-3 have been evaluated for inhibitory activity against α-glucosidase, which all showed weak inhibitory activities.

Two pentasaccharide resin glycosides from Argyreia acuta.

Two new compounds of acutacosides 1 and 2, pentasaccharide resin glycosides were isolated from the aerial parts of Argyreia acuta. The core of the two compounds was operculinic acid A, and they were esterfied at the same position, just one substituent group was linked at C-2 of Rha. The absolute configuration of the aglycone in the two compounds was established by Mosher's method, which was (11S)-hydroxyhexadecanoic acid (jalapinolic acid). Their structures were established by a combination of spectroscopic and chemical methods.

[UPLC fingerprint of rhei radix et rhizoma from different habitats].

OBJECTIVE: To establish the UPLC fingerprint of Rhei Radix et Rhizoma and reference crude drugs, analyze the characteristics among fingerprints of three species of reference crude drugs and the common components of Rhei Radix et Rhizoma, and compare the application of different analysis methods. METHODS: UPLC procedure was performed on ACQUITY BEH C18 chromatographic column with mobile phase consisted of water (contained 0.1% phosphoric acid)-acetonitrile (gradient elution) at a flow rate of 0.21 mL/min. Detection wavelength was set at 260 nm and the column temperature was set at 30 degrees C. Fingerprints were analyzed by similarity evaluation, cluster analysis and principal component analysis. RESULTS: There were obvious characteristics among fingerprints of three species of reference crude drugs, 19 common chromatographic peaks were obtained from Rhei Radix et Rhizoma and 14 peaks were identified according to standard reference substances and by HPLC-MS. The cluster analysis and similarity evaluation showed the same result that 21 batches of sample were grouped into 5 categories and the result had no direct correlation with the botanical species. Both the contents of4 important ingredients suggested by principal component analysis and the whole fingerprint analysis were necessary in quality evaluation of Rhei Radix et Rhizoma. There was certain limitation in quality evaluation of multiple sources drug which analysis by similarity evaluation and cluster analysis. CONCLUSION: The method with good reproducibility and separation saves time and solvent, it can be used in identification of three species of reference crude drugs but can not be used in species identification of commercial Rhei Radix et Rhizoma.

[Study on the extraction process of total flavonoids from Psoralea corylifolia by enzyme-assisted technique].

OBJECTIVE: To study the optimum extraction process of total flavonoids from Psoralea coryl folia by cellulose-assisted technique. METHODS: Based on single-factor experiments, the effects of pH value, temperature of enzymatic hydrolysis, time of enzymatic hydrolysis and enzyme amount on the extraction yields of total flavonoids from Psoralea corylifolia were studied by response surface methodology. RESULTS: The optimum enzyme-assisted extraction process was: pH value 4.9, temperature 46 degrees C, time 150 min and enzyme amount 7.2 mg/g,under this condition,the relative error of the observed and predicted values was 1.16%. CONCLUSION: The optimum enzyme-assisted extraction process is simple and feasible, the extraction rate of total flavonoids increases by 28% compared with ultrasonic extraction, so it can be used to extract total flavonoids from Psoralea corylifolia.

[Study on the effects of different compatibility of guizhi decoction on component of volatile oil from Cinnamomum cassia by GC-MS].

OBJECTIVE: To study the changes of volatile oil from different compatibility of Guizhi decoction and explore their connection. METHODS: The volatile oil of Cinnamomum cassia and different compatibility of Guizhi decoction extracted by steam distillation were analyzed by GC-MS. RESULTS: The main components of volatile oil in Cinnamomum cassia were found in different compatibility of Guizhi decoction and they accounted the most amount of total volatile oil,but the contents of the main components were decreased, there were more components existed in different compatibility of Guizhi decoction than those in Cinnamomum cassia, the new components came from Zingiber officinale mostly. CONCLUSION: GC-MS can be used to reflect the changes of volatile oil from different compatibility of Guizhi decoction, and the result will provide some evidence for the research of regular pattern of compatibility in Guizhi decoction.

[Studies on phloroglucinol derivatives of Dryopteris fragrans L].

OBJECTIVE: To study the phloroglucinol derivatives of Dryopteris fragrans. METHODS: Isolation and purification were carried out on repeated silica gel, Sephadex LH-20 column chromatography and prepare HPLC. The structures of the compounds were determined by physicochemical properties and spectral analysis. RESULTS: Four compounds were isolated and identified as aspidin PB (I), dryofragin (II), aspidinol (III), aspidin BB (IV). CONCLUSION: Compounds IV is isolated from this plant for the first time.

[Study on terpene of Dryopteris fragrans L].

OBJECTIVE: To study the terpene of Dryopteris fragrans. METHODS: Isolation and purification were carried out on repeated silica gel, Sephadex LH-20 column chromatography and prepare HPLC. The structures of the compounds were determined by physicochemical properties and spectral analysis. RESULTS: Four compounds were isolated and identified as 10-hydroxyl-15-oxo-alpha-cadinol (I), albicany acetate (II), alpha-cadinene (III), albicanol (IV). CONCLUSION: Compounds I is isolated from this plant for the first time.