Author(s)

Ajay P. Singh¹, Yifei Wang¹, Rachel M. Olson², Devanand Luthria³, Gary S. Banuelos⁴, Sajeemas Pasakdee⁴, Nicholi Vorsa^1*, Ted Wilson^2*

¹Department of Plant Biology & Pathology Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.
²Department of Biology, Winona State University, Winona, MN, USA.
³USDA, Agricultural Research Service Food Composition and Methods Development Lab, Beltsville, MD, USA.
⁴USDA, Agricultural Research Service San Joaquin Valley Agricultural Sciences Center, Parlier, CA, USA.

Eggplant fruits are known to contain different classes of phenolic phytochemicals (flavonols, phenolic acids, and anthocyanins) that can exert beneficial effects on human health. This study developed methods for the qualitative and quantitative composition analysis of phenolic compounds in the skin of eggplant fruits harvested following conventional and certified organic farming conditions. Eggplant skin was extracted using aqueous methanol prior to phenolic profiling with UHPLC-ESI-MS-MS. Eggplant skin extracts yielded a profile of 16 phenolic acids, 4 anthocyanins, and 11 flavonols, the first report of quercetin-3-diglucoside, myricetin-3-neohesperidoside, myricetin-3-galactoside, kaempferol-3,7-diglucoside, kaempferol-diglucoside and quercetin-3-rhamnoside. Polyphenolic extracts from all sources potently delayed the cupric ion-mediated lag-time for LDL lipid oxidation and protected Apo-B100 proteins against oxidative modification. Organic growing environment positively influences eggplant skin extract phenolic profile but not antioxidant capacity. In conclusion, eggplant skin has a robust profile of phenolic phytochemicals with excellent antioxidant properties.

Eggplant Skin, Polyphenols, LDL Antioxidant Activity, Conventional and Organic, HPLC, LC-MS

Singh, A. , Wang, Y. , Olson, R. , Luthria, D. , Banuelos, G. , Pasakdee, S. , Vorsa, N. and Wilson, T. (2017) LC-MS-MS Analysis and the Antioxidant Activity of Flavonoids from Eggplant Skins Grown in Organic and Conventional Environments. Food and Nutrition Sciences, 8, 873-888. doi: 10.4236/fns.2017.89063.