It occurs the increasing production of the agro-industrial waste which is a great environmental problem that we need to face. Through a critical review of recent successes (2023–2024) in green extraction technologies for conversion of agro-waste to valuable bioactive compounds for use in the food and nutraceutical sectors, this study is conducted. The paper focuses on polyphenols, flavonoids and essential oils from their corresponding agro-waste sources by extraction using non-thermal techniques, namely; pulsed electric field (PEF), ultrasound assisted extraction (UAE) using deep eutedic solvents (DES) and supercritical fluid extraction (SFE-CO₂). Synergistic experiments on emerging hybrid methods of enzyme assisted microwave extraction (EA-MAE) and ohmic heating combined with solvent free extraction to enhance yield but preserve compound integrity are explored. The use of the artificial neural networks (ANN) and genetic algorithms are discussed within the context of extraction process optimization integration of artificial intelligence (ai) models. Plant based proteins, natural preservatives, nanoemulsions, probiotic synbiotics from agro-waste and its valorization pathways are reviewed focusing on the utilization of the plant-based proteins in the development of functional foods and nutraceuticals. The feasibility of these technologies is assessed using sustainability metric, such as life cycle assessment (LCA), regulatory challenge and economic viability. Then, future directions of the paper are outlined, namely the integration of zero waste and higher consumer acceptance of upcycled products to promote a circular bioeconomy.