Simultaneous estimation of scavenging capacities of peach extract for multiple reactive oxygen species by fluorescence fingerprint method

Abstract

In this study, the potential of using fluorescence fingerprint, also known as fluorescence excitation-emission matrix, for estimating the scavenging capacity of peach extract on reactive oxygen species (ROS) was investigated. Samples from each of the five cultivars (Asama Hakuto, Hakuho, Kawanakajima Hakuto, Natsukko and Ougonto) were freeze-dried and crushed. The scavenging capacities of peach extracts for the target ROS (hydroxyl, superoxide, alkoxyl radicals and singlet oxygen) were measured by electron paramagnetic resonance spin trapping method. Fluorescence fingerprints of the same samples were obtained. Partial least squares regression analysis was carried out to develop prediction models for ROS scavenging capacity. The models were assessed by external validation. Fluorescence fingerprint was found to accurately estimate the scavenging capacity for the alkoxyl and superoxide radicals with the prediction error of 0.06mmoltroloxeq./mL and 0.31mmolα-lipoicacideq./mL with a coefficient of determination of prediction (R²P) of 0.78 and 0.91, respectively.

Keywords: Electron paramagnetic resonance (EPR); Fluorescence fingerprint; Peach; Procyanidins; Scavenging capacity.