Determination of Prooxidant Activities of Several Fruit Juices and Herbs

Abstract

Under oxidative stress conditions, which are defined as the deterioration of antioxidant and prooxidant balance in the organism in favor of prooxidants, ROS species that trigger the formation of various diseases occur. The fact that these harmful species cause oxidative damage to biological macromolecules is expressed as prooxidant activity. In this study, Cu(II)‒catalyzed prooxidant activities of pomegranate, apricot, peach, and pear juices and extracts of mint, white tea, and rosehip were measured by using gold nanoclusters synthesized via chicken egg white proteins. Fluorometric and spectrophotometric gold nanocluster biosensors and carbonyl assay were used. The fruit juices were used directly by diluting with pure water. Herbal plant samples were extracted in an ultrasonic water bath, filtered through microfilters, and stored in the refrigerator. Total prooxidant activities of fruit juices and herbal plants were calculated in terms of mM epicatechin equivalent, and the results obtained by applying all methods were compared with each other. It has been found that the applied methods can be used to accurately determine the total prooxidant activity of many food products.