Harnessing cold plasma for sustainable extraction of bioactive compounds: a critical review of mechanisms and applications

Cold plasma (CP) represents a transformative, non-thermal approach for enhancing the extraction efficiency of bioactive compounds from diverse plant matrices. This review provides a critical synthesis of recent advances in CP-assisted extraction, emphasizing its mechanisms, optimization parameters, and comparative effectiveness relative to conventional and emerging extraction methods. CP operates through the synergistic action of reactive oxygen and nitrogen species, inducing cell wall disruption, surface activation, and in some cases, induced metabolic responses within plant tissues. Comprehensive analysis reveals that treatment parameters, including voltage, gas composition, and exposure time, have significant, compound-specific impacts on extraction yield and bioactive stability. Notably, CP enhances the recovery of polyphenols, flavonoids, and essential oils from multiple plant types, often outperforming conventional solvent-based techniques while aligning with green chemistry principles. However, improper parameter optimization can lead to oxidative degradation, particularly in thermolabile compounds like carotenoids and volatile oils. The review identifies key research gaps in the standardization of CP protocols, matrix-specific optimization, and industrial scalability. Future research should focus on mechanistic elucidation, post-extraction stability, and integration with complementary technologies to fully harness the potential of CP in sustainable food and pharmaceutical applications.