Electron spin resonance of free radicals produced by ultraviolet photolysis in some vegetables and their juices

Abstract

Paramagnetic species produced by ultraviolet photolysis in various vegetables of domestic origin have been investigated by electron spin resonance technique. The ESR spectra of the small cut pieces of the vegetable fleshes and their frozen juices have been investigated before and under UV photolysis. The samples of potato and carrod exhibit too complex ESR spectra, but parsley, dill, white radish and green pepper do not exhibit any ESR signal before UV photolysis at 113 K. However both the small cut pieces of fleshes of potato, carrot, parsley, dill, white radish and green pepper and their juices exhibit ESR spectra during UV photolysis that we attributed to the HCO and CO2– radicals. The ESR parameters of these radicals have been obtained and the origins of these radicals have been shown to be the glucose molecules in the carbohydrate chains of these substances. © 1991, Taylor & Francis Group, LLC. All rights reserved.