title: Role of hydroxyl radical in modification of cell wall polysaccharides and aril breakdown during senescence of harvested longan fruit.
abstract: The effects of reactive oxygen species (ROS), especially hydroxyl radical (OH), on cellular wall disassembly in vitro and in vivo, and aril breakdown in longan fruit, were investigated. OH caused the disassembly of cell wall material (CWM) in vitro, demonstrated by the increases of total sugars and uronic acid released, and the downshift in molecular mass of CDTA soluble pectin (CSP) and Na2CO3 soluble pectin (CO3-SP). In addition, OH resulted in decreased CO3-SP content and increased CSP content in CWM suspension, suggesting the conversion of CO3-SP to CSP. Application of exogenous OH accelerated aril breakdown in longan fruit while the process was delayed by l-cysteine·HCl, a ROS scavenger. Furthermore, lower CWM content and decreased molecular mass of pectins were observed in OH-treated fruit. These results indicated that OH contributed to the degradation of cell wall polysaccharides, resulting in aril breakdown in longan fruit.
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China. Electronic address: xwduan@scbg.ac.cn.
authors.forename: Xuewu
authors.initials: X
authors.lastname: Duan
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China.
authors.forename: Jiangfeng
authors.initials: J
authors.lastname: Sheng
authors.affiliation: College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Hetong
authors.initials: H
authors.lastname: Lin
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China.
authors.forename: Yueming
authors.initials: Y
authors.lastname: Jiang
keywords: ()OH; Cellular wall disassembly; Longan; Polysaccharides; Reactive oxygen species