Electron spin resonance characterization of radical components in irradiated black pepper skin and core

► We identified the radical components in irradiated black pepper skin and core. ► The ESR spectra near g=2.005 with 3-7 lines were emerged after irradiation. ► Spectra simulated basing on the content and the stability of radical from the plant constituents. ► Cellulose radical component in black pepper skin was highly stable. ► Single signal near g=2.005 was the most stable in black pepper core.