Recombinant Expression of Archaeal Superoxide Dismutases in Plant Cell Cultures: A Sustainable Solution with Potential Application in the Food Industry

Superoxide dismutase (SOD) is a fundamental antioxidant enzyme that neutralises super-oxide ions, one of the main reactive oxygen species (ROS). Extremophile organisms possess enzymesthat offer high stability and catalytic performances under a wide range of conditions, thus represent-ing an exceptional source of biocatalysts useful for industrial processes. In this study, SODs from thethermo-halophilic Aeropyrum pernix (SODAp) and the thermo-acidophilic Saccharolobus solfataricus(SODSs) were heterologously expressed in transgenic tomato cell cultures. Cell extracts enriched withSODAp and SODSs showed a remarkable resistance to salt and low pHs, respectively, together withoptimal activity at high temperatures. Moreover, the treatment of tuna fillets with SODAp-extractsinduced an extension of the shelf-life of this product without resorting to the use of illicit substances.The results suggested that the recombinant plant extracts enriched with the extremozymes couldfind potential applications as dietary supplements in the nutrition sector or as additives in the foodpreservation area, representing a more natural and appealing alternative to chemical preservativesfor the market