A fast screening method for antioxidant capacity of plant leaves based on red fluorescence was studied. The red fluorescence of young and matured leaves of A. occidentale, M. indica, S. dulcis, belonging to Anacardiaceae, and P. betle Linn., P. sarmentosum, and P. crocatum of Piperaceae family using fluorescence imaging microscopy was investigated. The total antioxidant capacity of methanol extracts of plant leaves was determined using the 2,2-diphenyl-1- picrylhydrazine (DPPH) free radical scavenging assay. From young to matured leaves of the plants belonging to the Anacardiaceae and Piperaceae, the red fluorescence and the total antioxidant capacity show the same trend.
Keywords: antioxidant; Anacardiaceae; DPPH assay; Piperaceae; Red fluorescence