Isolation of antioxidants from Psoralea corylifolia fruits using high-speed counter-current chromatography guided by thin layer chromatography-antioxidant autographic assay.
A combinative method using high-speed counter-current chromatography (HSCCC) and thin layer chromatography (TLC) as an antioxidant autographic assay was developed to separate antioxidant components from the fruits of Psoralea corylifolia. Under the guidance of TLC bioautography, eight compounds including five flavonoids and three coumarins were successfully separated from the fruits of P. corylifolia by HSCCC with an optimized two-phase solvent system, n-hexane-ethyl acetate-methanol-water (1:1.1:1.3:1, v/v/v/v). The separation produced 5.91mg psoralen, 6.26mg isopsoralen, 3.19mg psoralidin, 0.92mg corylifol A, and 2.43mg bavachinin with corresponding purities of 99.5, 99.8, 99.4, 96.4, and 99.0%, as well as three sub-fractions, in a single run from 250mg ethyl acetate fraction of P. corylifolia extract. Following an additional clean-up step by preparative TLC, 0.4mg 8-prenyldaidzein (purity 91.7%), 4.18mg neobavaisoflavone (purity 97.4%) and 4.36mg isobavachalcone (purity 96.8%) were separated from the three individual sub-fractions. The structures of the isolated compounds were identified by (1)H NMR and (13)C NMR. The results of antioxidant activity estimation by electron spin resonance (ESR) method showed that psoralidin was the most active antioxidant with an IC50 value of 44.7microM. This is the first report on simultaneous separation of eight compounds from P. corylifolia by HSCCC.
Xiao
Guodong
G
The MOE Key Laboratory for Standardization of Chinese Medicines, the SATCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, and the Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Zhangjiang Hi-Tech Park, Shanghai 201210, China.
Li
Guowen
G
Chen
Liang
L
Zhang
Zijia
Z
Yin
Jun-Jie
JJ
Wu
Tao
T
Cheng
Zhihong
Z
Wei
Xiaohui
X
Wang
Zhengtao
Z
D000085:Acetates / Q000737:chemistry; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification*; D001345:Autoradiography / Q000379:methods; D001713:Biphenyl Compounds / Q000737:chemistry; D002855:Chromatography, Thin Layer / Q000379:methods*; D003374:Coumarins / Q000737:chemistry / Q000302:isolation & purification; D003377:Countercurrent Distribution / Q000379:methods*; D000431:Ethanol / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification; D005638:Fruit / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular; D010851:Picrates / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*; D029907:Psoralea / Q000737:chemistry*
D000085:Acetates; D000975:Antioxidants; D001713:Biphenyl Compounds; D003374:Coumarins; D005419:Flavonoids; D010851:Picrates; D010936:Plant Extracts; D000431:Ethanol; C007650:ethyl acetate; C004931:1,1-diphenyl-2-picrylhydrazyl