title: Purification, antioxidant activity and protein-precipitating capacity of punicalin from pomegranate husk.
abstract: Punicalin is a kind of ellagitannin, existing in pomegranate husk, and has shown remarkable biological activities. A rapid and large-scale separation method of punicalin from pomegranate husk was established, using medium pressure liquid chromatography (MPLC). The optimal mobile phase consisted of 5% methanol and 0.1% (v/v) TFA in water, and the optimal loading amount and flow rate were 1.0 g and 80 ml/min, respectively. Under this condition, 339 mg of 95.9% punicalin could be obtained in 40 min. 59.7 mg of 78.0% gallic acid could be separated simultaneously. This method was practical for industrial utilisation of pomegranate husk. Afterwards, the antioxidant and protein-precipitating capacities of the purified punicalin, together with punicalagin, were evaluated. Results showed that punicalin had strong antioxidant activity, and it exhibited a low affinity for protein. This suggested that the antioxidant of punicalin would not be greatly masked by tannin-protein precipitation in application, and hence confirmed punicalin to be a promising antioxidant.
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Hongchao
authors.initials: H
authors.lastname: Zhang
authors.forename: Hao
authors.initials: H
authors.lastname: Liang
authors.forename: Qipeng
authors.initials: Q
authors.lastname: Yuan
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification; D011232:Chemical Precipitation; D047348:Hydrolyzable Tannins / Q000737:chemistry* / Q000302:isolation & purification; D029561:Lythraceae / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D011506:Proteins / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D047348:Hydrolyzable Tannins; D010936:Plant Extracts; D011506:Proteins; C115643:punicalin