Green and Efficient Extraction Strategies for Anthocyanins From Purple Plant Sources: Advances, Challenges, and Functional Potential

Anthocyanins are water-soluble flavonoid pigments that contribute to the red, purple, and blue hues of many fruits, vegetables, and cereals. Beyond their esthetic function, they exhibit potent antioxidant, anti-inflammatory, cardioprotective, and neuroprotective properties, making them valuable bioactive compounds for food, cosmetic, and pharmaceutical industries. However, their industrial utilization is limited by instability and susceptibility to degradation during extraction, processing, and storage. Conventional solvent extraction methods often involve toxic solvents and high energy consumption, reducing both yield and sustainability. To address these challenges, green extraction technologies—such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), pressurized liquid extraction (PLE), and supercritical fluid extraction (SFE)—have been developed to enhance efficiency, minimize solvent use, and preserve anthocyanin integrity. These approaches align with the principles of circular economy and green chemistry by reducing environmental impact and enabling the valorization of agricultural and food by-products. Nevertheless, issues related to scalability, selectivity, and stability under industrial conditions still need to be addressed. This review summarizes recent advances in sustainable extraction of anthocyanins from purple plant sources, discusses factors influencing their stability and recovery, and highlights their growing potential as natural colorants and functional ingredients in next-generation food and nutraceutical formulations.