Investigation of Oxidative Damage Mechanism of <i>Chlorella sorokiniana</i> by Gas–Liquid Phase Plasma

This study explores the mechanisms of oxidative damage in Chlorella sorokiniana under continuous gas-liquid phase plasma exposure. The oxidative damage mechanism of C. sorokiniana was revealed through multiple analytical techniques, including scanning electron microscopy (SEM), flow cytometry (FCM), and fluorescence excitation-emission matrix (EEM). Plasma-induced damage to algal cell membranes, causing seepage of photosynthetic pigments and dissolved organic matter; chlorophyll fluorescence changes confirmed damage to the photosynthetic system. Alterations in MDA, intracellular ROS/NO, and antioxidant enzyme activities reflect lipid peroxidation and oxidative stress levels. These results show that plasma induces oxidative damage to algal membranes, intracellular components, and photosystems via reactive oxygen and nitrogen species (RONS). C. sorokiniana activates its antioxidant defense system under stress. This gradual, cumulative damage exerts distinct biological effects at different times. The findings support the precise control of low-temperature plasma for beneficial microorganisms and provide a basis for advancing microalgae transformation technologies.