UHPLC-PDA-ESI/HRMS/MSn analysis of anthocyanins, flavonol glycosides, and hydroxycinnamic acid derivatives in red mustard green (Brassica juncea (L) Coss variety)

Authors: LIN, LONG-ZE - Johns Hopkins University; SUN, JIANGHAO - Johns Hopkins University; Chen, Pei; Harnly, James - Jim

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/3/2011
Publication Date: 12/3/2011
Citation: Lin, L., Sun, J., Chen, P., Harnly, J.M. 2011. UHPLC-PDA-ESI/HRMS/MSn analysis of anthocyanins, flavonol glycosides, and hydroxycinnamic acid derivatives in red mustard green (Brassica juncea (L) Coss variety). Journal of Agricultural and Food Chemistry. 60:544-553.

Interpretive Summary: Many classes of dietary polyphenols, such as anthocyanins, flavonol glycosides, and hydroxycinnamic acid derivatives, have been linked to resistance to cancer, diabetes, infections, inflammation, and neurological diseases related to the aging process. Thus the systematic identification of food poylphenolic components is important. In this study we identified 67 anthocyanins, 102 flavonol glycosides, and 40 hydroxycinnamic acid derivatives in red mustard greens, a brassica vegetable found in local food stores in recent years. Among the identified compound, 90 are reported in brassica vegetables for the first time. This data will expand our knowledge on food polyphenolic compounds.

Technical Abstract: An UHPLC-PDA-ESI/HRMS/MSn profiling method was used for a comprehensive study of the polyphenols in red mustard greens and identified 209 phenolic compounds: 67 anthocyanin, 102 flavonol glycosides, and 40 hydroxycinnamic acid derivatives. The glycosylation patterns of the flavonoids were assigned based on direct comparison of the parent flavonoid glycosides with reference compounds. The putative identifications were obtained from tandem mass data analysis and confirmed by the retention time, elution order, and the UV/Vis and high resolution mass spectra. Further identifications were made by comparing the LC-PDA-MSn data with those of reference compounds in the polyphenolic database and in the literature. Twenty-seven acylated cyanidin 3-sophoroside-5-diglucoside, 24 acylated cyanidin 3-sophoroside-5-glucosides, 3 acylated cyanidin triglucoside-5-glucosides, 40 flavonol glycosides and 10 hydroxycinnamic acid derivatives were detected for the first time in brassica vegetables. At least 50 of these compounds are reported for the first time in any plant materials.