title: Antioxidant capacities and polyphenolics of Chinese cabbage (Brassica rapa L. ssp. Pekinensis) leaves.
abstract: Chinese cabbage (Brassica rapa L. ssp. Pekinensis) is a green leafy vegetable used mainly in kimchi, salted and fermented dishes. Consumer preference for the leaf portion differs according to the type of dishes. In this study, Chinese cabbage was divided into three parts, and their antioxidant activities were investigated through in vitro assays. The total phenolic contents (TPC), total flavonoid contents (TFC), and vitamin C contents were also determined as indicators of antioxidant contents. The phenolic acids and flavonoids were separated and identified using high performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS). The outer leaf had the strongest antioxidant activity with the maximum antioxidant contents, followed by the mid- and inner leaves. Principal component analysis (PCA) revealed that outer leaf is positively related to caffeic acid, p-coumaric acid, ferulic acid, and myricetin contents, whereas the mid- and inner leaves are negatively related to sinapic acid contents.
authors.affiliation: School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: Gi-Un
authors.initials: GU
authors.lastname: Seong
authors.affiliation: Food and Bio-industry Research Institute, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: In-Wook
authors.initials: IW
authors.lastname: Hwang
authors.affiliation: School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701, Republic of Korea. Electronic address: kchung@knu.ac.kr.
authors.forename: Shin-Kyo
authors.initials: SK
authors.lastname: Chung
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D001205:Ascorbic Acid / Q000032:analysis*; D001937:Brassica / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003373:Coumaric Acids / Q000032:analysis; D005419:Flavonoids / Q000032:analysis*; D010636:Phenols / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry*; D011422:Propionates
chemical_list: D000975:Antioxidants; D003373:Coumaric Acids; D005419:Flavonoids; D010636:Phenols; D011422:Propionates; C073734:sinapinic acid; C040015:myricetin; C004999:ferulic acid; C495469:p-coumaric acid; D001205:Ascorbic Acid
keywords: Antioxidants; Chinese cabbage leaves; Polyphenolics; Principal component analysis; Sinapic acid