title: Ultrasound extraction of polysaccharides from mulberry leaves and their effect on enhancing antioxidant activity.
abstract: A Box-Behnken design (BBD) was applied to optimize the ultrasound-assisted extraction of polysaccharides from mulberry leaves. Under the optimum conditions of an extraction temperature of 57 °C, an extraction time of 80 min and a liquid/solid ratio of 53 mL/g, the mulberry leaf polysaccharide (MLP) yield was 6.92 ± 0.29%. Then, three fractions of MLPs were obtained by deproteinization, dialysis and decolorization. The carbohydrate content, FT-IR spectrum and monosaccharide composition of the MLPs were also investigated. The antioxidant activities of the three fractions were compared, and the results indicated that the antioxidant activities decreased with the increasing MLP purity. Therefore, highly concentrated MLPs were shown to have very little antioxidant activity. After quercetin (10 μg/mL) was added, the antioxidant activities were improved significantly. This result showed that MLPs and quercetin have a synergistic effect on the antioxidant activity. Although the MLPs have very little antioxidant activity alone, they greatly enhance the antioxidant activity of flavonoids. Thus, MLPs can be used as an antioxidant activity enhancer in the food industry.
authors.affiliation: College of Biotechonlogy and Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, China.
authors.forename: Dong-Yang
authors.initials: DY
authors.lastname: Zhang
authors.affiliation: College of Biotechonlogy and Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wan
authors.affiliation: College of Biotechonlogy and Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, China.
authors.forename: Jian-Yi
authors.initials: JY
authors.lastname: Xu
authors.affiliation: College of Biotechonlogy and Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, China. Electronic address: zdy87227@163.com.
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Wu
authors.affiliation: College of Biotechonlogy and Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, China.
authors.forename: Long
authors.initials: L
authors.lastname: Li
authors.affiliation: College of Biotechonlogy and Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, China.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Yao
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D005591:Chemical Fractionation / Q000379:methods; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D031625:Morus / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry* / Q000494:pharmacology; D013010:Sonication / Q000379:methods
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010936:Plant Extracts; D011134:Polysaccharides
keywords: Antioxidant activity; BBD test; Mulberry leaf; Polysaccharides; Ultrasound extraction