title: Antioxidant activity of polysaccharide-enriched fractions extracted from pulp tissue of Litchi Chinensis sonn.
abstract: Natural antioxidants such as polysaccharides with strong antioxidant activities are used to protect against oxidative damage, yet little is known so far about the antioxidant effects of litchi fruit polysaccharides. In the present study, four different polysaccharide-enriched fractions were isolated from litchi pulp tissue and partially purified by a stepwise method of ethyl alcohol (EtOH) precipitation. Their chemical and physical characteristics were determined by chemical methods, gas chromatography and IR spectrophotometry. Antioxidant activities of these fractions were investigated using various in vitro assay systems. These four polysaccharide-enriched fractions exhibited a dose-dependent free radical scavenging activity as shown by their DPPH radical, superoxide anion and hydroxyl radical inhibition, chelating ability and reducing power. Among the different fractions, LFP-III showed the strongest scavenging activity against DPPH radical, superoxide and hydroxyl radicals and chelating ability. These findings suggest litchi polysaccharides from pulp tissue have potential as functional foods with enhanced antioxidant activity.
authors.affiliation: Key Laboratory of Functional Food, Ministry of Agriculture, Bio-tech Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China.
authors.forename: Fanli
authors.initials: F
authors.lastname: Kong
authors.forename: Mingwei
authors.initials: M
authors.lastname: Zhang
authors.forename: Sentai
authors.initials: S
authors.lastname: Liao
authors.forename: Shujuan
authors.initials: S
authors.lastname: Yu
authors.forename: Jianwei
authors.initials: J
authors.lastname: Chi
authors.forename: Zhencheng
authors.initials: Z
authors.lastname: Wei
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000431:Ethanol; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D032125:Litchi / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D011134:Polysaccharides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D010936:Plant Extracts; D011134:Polysaccharides; D000431:Ethanol