Identification of Radiation-Processed Edible Grains and Seeds using Single Cell Microgel Electrophoresis Assay: A Comparative Analysis

The DNA Comet assay (microgel electrophoresis method) is a recommended technique for detection of radiation treatment in food containing DNA material. It involves isolating cells/nuclei (DNAs) from both un-irradiated and irradiated samples of food and embedding them on microscope slides, lysing the cells/nuclei, performing electrophoresis, staining the cells/nuclei and then evaluating the patterns of migration of DNA in agarose gel. In this study, the assay was applied to identify irradiated grains and seeds commonly consumed by humans and animals such as wheat, melon seeds, sesame seeds, red lentils and pinto beans. Samples were irradiated within a permissible dose range and microscope slides were evaluated under an ordinary transmission microscope. The controlled samples showed intact membrane cells/nuclei while irradiated samples displayed dose-dependent comets with varying shapes, lengths and sizes of the tail. On the basis of comet morphology, this method enables rapid screening and differentiation of food samples exposed to different radiation doses, providing a valuable tool for food quality and safety assessment. The study's main results demonstrate the effectiveness of the DNA Comet assay in distinguishing between irradiated and un-irradiated food samples, complementing the microscopic results obtained.