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ABSTRACT: To study chemical constituents contained in Aeschynanthus moningeriae.
The chemical constituents were separated and purified by column chromatographic methods such as Diaion HP-20, Toyopearl HW-40, Sephadex LH-20, MCI-Gel CHP-20, RP18 and normal phase silica gel. Their structures were identified on the basis of physiochemical property and spectral techniques (1H, 13C-NMR, DEPT, 1H-1H COSY, HSQC, HMBC, HR-MS).
Twelve compounds were separated and identified as 5,7-dihydroxy-8-C-beta-D-glucosyl-chromone (1), 5-hydroxyl-7,4'-dimethoxyl-flavone (2), 2,3,19, 24-tetrahydroxy-urs12-en-28-oic acid (3), 2,3,19, 24-tetrahydroxy-urs-12-en-28-oic acid ester-28-O-beta-D-gucoside (4), 5-hydroxyl-6,4'-dimethoxyl-7-O-[alpha-L-rhamnosyl-(1-->6)]-beta-D-glucopyranosyl-flavone (5), 5,7,3',4'-tetrahydroxy-6-C-beta-D-glucosyl-flavonol (6), 5,7-dihydroxy-6-C-beta-D-glucosyl-flavonones (7), 5,7, 3',4'-tetrahydroxy-6-C-beta-D-glucosyl-dihydroflavonol (8), daucosterol (9), stigmasterol (10), beta-sitosterol (11), and 3-O-beta-D-glucosyl-stigmasterol (12).
Compound 1 is a new compound, while other compounds were separated from this plant for the first time.
Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 07/2012; 37(13):1963-7.
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ABSTRACT: Abelmoschus esculentus L. is a healthy vegetable belonging to the family Malvaceae. This article reports the contents of total phenolics (TP) and total flavonoids (TF) in 80% methanol extracts of the flower (FL), fruit (FR), leaf (L), and seed (S) of A. esculentus, and in 0, 10, 30, 50, and 70% methanol eluates (ME), through the HP-20 column chromatography of 80% of the methanol fruit extract after it is defatted with petroleum and extracted with ethyl acetate. All the names of the samples are shortened for AEE-FL, AEE-FR, AEE-L, AEE-S and 0% MEF-WE, 10% MEF-WE, 30% MEF-WE, 50% MEF-WE, 70% MEF-WE respectively. In addition, the effects of the aforementioned extracts on 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging and on ferric reducing antioxidant power (FRAP) have been evaluated.
The antioxidant activity of the extracts and the enrichment fraction of A. esculentus were also evaluated by two assays, the DPPH radical-scavenging and ferric reducing antioxidant power (FRAP). The content measurement of TF and TP adopts the UV-2102 PCS method, and the measurement of the antioxidant activity adopts the Infinite M 200 method.
The experiment results show that all the different parts and different enrichment fractions of the water extracts of A. esculentus contain phenolics and flavonoids. Through the research of antioxidant activity we know that all the parts of the methanol extracts and different enrichment fractions of water extracts in the A. esculentus have the effect of scavenging free radicals, among which the antioxidant activity in the 50% MEF-WE part is the strongest. Here, the main components of antioxidant activity must be the flavonoids and phenolics, and furthermore, we know that there is a direct relationship between the contents of flavonoids and phenolics and the antioxidant activity.
The study suggests that A. esculentus may be the potential rich source of natural antioxidant. The experiment result provided a scientific basis for the further research and development of A. esculentus.
Pharmacognosy Magazine 04/2012; 8(30):156-61. · 1.16 Impact Factor
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ABSTRACT: A high-performance liquid chromatography fingerprint of different variants of Phyllostachys pubescens was developed for the source discrimination and quality control of Phyllostachys pubescens medicines produced in Zhejiang Province, China.
Samples of Phyllostachys pubescens collected from nine cultivars in Zhejiang Province were used to establish the fingerprint. Taking the chromatographic peak (isoorientin) as the reference peak, the chromatographic column was Sunfire C(18) ODS (250 mm×4.6 mm, 5 μm) at a column temperature of 25°C. The mobile phase was acetonitrile 0.8% acetic acid water solution (in a gradient elution mode) at a flow rate of 1 ml/min. The detection wavelength was 330 nm.
20 common peaks were established in the chromatographic fingerprints of Phyllostachys pubescens. And then by comparing the UV and standard substance with those of the authentic standards and literature, eight main peaks in the fingerprints were identified. Data of nine cultivars were evaluated statistically using similarity analysis, hierarchical cluster analysis (HCA) in order to establish a similarity standard of fingerprint for quality control of Phyllostachys pubescens, then to classify the samples. The similarity indexes were all above 0.95 between reference chromatogram and each sample's chromatogram.
in this study, the methods established are reliable, and could be used to evaluate the quality and to identify the species of Phyllostachys pubescens in the future.
Pharmacognosy Magazine 01/2012; 8(29):42-8. · 1.16 Impact Factor
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ABSTRACT: Abelmoschus esculentus L. belonging to the family Malvaceae is a kind of one year herbage plant, which is one of the most important vegetables widely grown in Nigeria for its tender fruits and young leaves. It's easy to be cultivated and grows well in both tropical and temperate zones, that is, it is widely planted from Africa to Asia, South European to America. A new flavonol glycoside characterized as 5,7,3',4'-tetrahydroxy-4''-O-methyl flavonol -3-O-β-D- glucopyranoside (1) has been isolated from the fruit of A. esculentus together with one known compound 5,7,3',4'-tetrahydroxy flavonol -3-O-[β-D-glucopyranosyl-(1→6)]-β-D-glucopyranoside (2). The structure of the new compound was elucidated on the basis of its spectral data, including 2-D NMR and mass (MS) spectra. The antioxidant activities of the isolated compounds 1 and 2 were evaluated by 2 assays, the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). The present work deals with the isolation, identification and antioxidant activity of the two compounds.
The compounds were isolated by Diaion HP-20, Sephedex LH-20 column chromatography methods, their structures were identified by physicochemical properties and spectroscopic analysis. The antioxidant activities of the isolated compounds 1 and 2 were evaluated by two assays, e.g., DPPH and FRAP.
Two flavonol glycosides have been isolated from the fruit of Abelmoschus esculentus L. for the first time, and the compound 1 was a new compound, the compound 2 was isolated from the plant for the first time.
The results show that the two flavonol glycosides have strong ability for scavenging DPPH and FRAP free radical by the experiment of antioxidant activities, so A. esculentus may be a natural antioxidants resource.
Pharmacognosy Magazine 01/2012; 8(29):12-5. · 1.16 Impact Factor
