title: Investigation of radiation-induced free radicals and luminescence properties in fresh pomegranate fruits.
abstract: Radiation-induced free radicals and luminescence properties were investigated in γ-irradiated (0-3 kGy) pomegranate ( Punica granatum L.) fruits. Photostimulated luminescence (PSL) analysis showed limited applicability, and only 3 kGy-irradiated pomegranates showed positive PSL values (>5000 PCs). Thermoluminescence (TL) glow curve features, such as intensity and the presence of maximum glow peak in radiation-specific temperature range (150-250 °C), provided definite proof of irradiation, and the TL ratios (TL1/TL2) also confirmed the reliability of TL results. Scanning electron microscopy energy dispersive X-ray (SEM-EDX) analysis of the separated minerals showed that feldspar and quartz minerals were responsible for the luminescence properties. Radiation-induced cellulose radicals were detected in the seeds and rinds by ESR analysis. The ESR results were better in freeze-dried samples than in alcohol-extracted ones. A positive correlation was found between the ESR and TL signal intensities and irradiation doses; however, the most promising detection of the irradiation status was possible through TL analysis.
authors.affiliation: School of Food Science and Biotechnology, Kyungpook National University , Daegu 702-701, South Korea.
authors.forename: Hafiz M
authors.initials: HM
authors.lastname: Shahbaz
authors.forename: Kashif
authors.initials: K
authors.lastname: Akram
authors.forename: Jae-Jun
authors.initials: JJ
authors.lastname: Ahn
authors.forename: Joong-Ho
authors.initials: JH
authors.lastname: Kwon
mesh_terms: D005514:Food Irradiation / Q000009:adverse effects; D005609:Free Radicals / Q000737:chemistry*; D005612:Freeze Drying; D005638:Fruit / Q000737:chemistry / Q000528:radiation effects*; D005720:Gamma Rays; D049449:Luminescence; D008163:Luminescent Measurements; D029561:Lythraceae / Q000737:chemistry / Q000528:radiation effects*; D008855:Microscopy, Electron, Scanning; D015203:Reproducibility of Results; D012639:Seeds / Q000737:chemistry / Q000528:radiation effects; D014965:X-Rays
chemical_list: D005609:Free Radicals