title: Structural elucidation and antioxidant activities of proanthocyanidins from Chinese bayberry (Myrica rubra Sieb. et Zucc.) leaves.
abstract: Proanthocyanidins in Chinese bayberry leaves (PCBLs) were qualitatively analyzed. NMR data suggest that PCBLs are mostly composed of (epi)gallocatechin gallate units. Matrix-assisted laser desorption time-of-flight MS data indicate 95 possible prodelphinidin structures, ranging from dimers to tridecamers. Preparative normal-phase HPLC and further analysis by reverse-phase HPLC together with electrospray ionization MS enabled detection of 20 compounds, including seven newly identified compounds in Chinese bayberry leaves. The antioxidant capacity of PCBLs was evaluated by (1,1-diphenyl-2-picryl-hydrazyl), ferric-reducing antioxidant power, and oxygen radical absorption capacity assays. The EC50 of DPPH radical scavenging activities (as 50% decrease in the initial DPPH concentration) were 7.60 µg. The FRAP and ORAC values were 8859.33 ± 978.39 and 12991.61 ± 1553.34 µmol Trolox equivalents per gram, respectively. The results indicate the high antioxidant potency of PCBLs.
authors.affiliation: Department of Food Science and Nutrition, College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou, PR China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Department of Food Science and Nutrition, College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou, PR China.
authors.forename: Liping
authors.initials: L
authors.lastname: Qiao
authors.affiliation: Department of Food Science and Nutrition, College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou, PR China.
authors.forename: Yuming
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Department of Food Science and Nutrition, College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou, PR China.
authors.forename: Xiaozhou
authors.initials: X
authors.lastname: Zhou
authors.affiliation: College of Life Science, Zhejiang University, Hangzhou, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Food Science and Nutrition, College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou, PR China.
authors.forename: Xingqian
authors.initials: X
authors.lastname: Ye
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D031641:Myrica / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D044945:Proanthocyanidins / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D044945:Proanthocyanidins