title: Enzyme release of phenolics from muscadine grape (Vitis rotundifolia Michx.) skins and seeds.
abstract: Enzyme degradation of plant cell wall polysaccharides can potentially enhance the release of bioactive phenolics. The aim of this study was to evaluate various combinations of solvent and enzyme, enzyme type (cellulase, pectinase, ß-glucosidase), and hydrolysis time (1, 4, 8, 24 h) on the release of muscadine grape skin and seed phenolics, and their antioxidant activities. Results showed that pre-treated muscadine skins and seeds with enzymes decreased total phenolic yield compared with solvent (50% ethanol) alone. Enzyme release of phenolics from skins of different muscadine varieties was significantly different while release from seeds was similar. Enzyme hydrolysis was found to shorten extraction time. Most importantly, enzyme hydrolysis modified the galloylated form of polyphenols to low molecular weight phenolics, releasing phenolic acids (especially gallic acid), and enhancing antioxidant activity.
authors.affiliation: Department of Food Science and Human Nutrition, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Changmou
authors.initials: C
authors.lastname: Xu
authors.affiliation: Department of Food Science and Human Nutrition, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Yavuz
authors.initials: Y
authors.lastname: Yagiz
authors.affiliation: Department of Food Science and Human Nutrition, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Wlodzimierz
authors.initials: W
authors.lastname: Borejsza-Wysocki
authors.affiliation: Center for Viticulture and Small Fruit Research, Florida Agricultural & Mechanical University, Tallahassee, FL 32317, United States.
authors.forename: Jiang
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Food Science and Human Nutrition, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Liwei
authors.initials: L
authors.lastname: Gu
authors.affiliation: Department of Food Science and Human Nutrition, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Milena M
authors.initials: MM
authors.lastname: Ramírez-Rodrigues
authors.affiliation: Department of Food Science and Human Nutrition, University of Florida, Gainesville, FL 32611, United States. Electronic address: unclemarty_2001@ufl.edu.
authors.forename: Maurice R
authors.initials: MR
authors.lastname: Marshall
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry*; D010636:Phenols / Q000032:analysis*; D010936:Plant Extracts; D059808:Polyphenols; D012639:Seeds / Q000737:chemistry; D027843:Vitis / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols
keywords: DPPH; Enzyme; Hydrolysis; Muscadine grape; Phenolics