Quantitative chemical analysis of flavonoids in purple fruited selections of pitanga (Eugenia uniflora L.)

Abstract

A variety of flavonoids have been quantified from purple-fruited seedling selections of pitanga (Eugenia uniflora L.). Flavonoids are widely known as antioxidants that function as photoprotectants in plants. Flavonoids have previously exhibited anticancer, antioxidant, and cardioprotectant effects. High Performance Liquid Chromatography was utilized to investigate the composition of flavonoids present in fruits of E. uniflora. Methods of quantification were improved using pre-purification methods to remove undesired compounds that may interfere with analyses. Lipophilic compounds were removed by a hexane/water partition. Pitanga extracts were passed through a preconditioned Waters Sep-Pak™ C18 column. Anthocyanins and flavonols were selectively separated using ethyl acetate and 0.1N HCl MeOH. A Waters XBridge™ column facilitated selective retention, resolution, and high sensitivity. The pitanga fruits are underutilized as possible sources of dietary antioxidants and relatively unknown to the public. These results will be useful to exemplify the pitanga as a nutritionally desirable crop for consumption.