From conventional to green extraction of saponins: A review on plant matrices and byproducts

Abstract

Saponins are plant-derived compounds with broad bioactivities and applications in pharmaceuticals, nutraceuticals, and cosmetics. Traditional extraction methods, although effective, often rely on toxic solvents, long processing times, and generating environmental burdens. Recently, greener alternatives such as supercritical fluid extraction, ultrasound, microwave, and enzyme-assisted techniques have gained momentum for improving efficiency while reducing hazardous inputs. This review provides a comparative evaluation of conventional and green extraction strategies. Beyond technical performance, it considers solvent recyclability, energy efficiency, lifecycle impacts, scalability, and techno-economic feasibility. Eco-friendly solvents, including deep eutectic solvents, hold promise but face limitations related to toxicological gaps, regulatory uncertainty, and scale-up. Major challenges across green approaches include process optimization for diverse plant matrices, lack of standardized methodologies, and insufficient environmental assessments to validate sustainability claims. The analysis emphasizes that greener extraction techniques can markedly lower ecological footprints but must be validated through recognized green chemistry metrics and lifecycle assessments. Future progress will require multidisciplinary integration of process engineering, environmental analysis, and economic evaluation. Hybrid systems and artificial intelligence-based optimization are highlighted as emerging tools. By consolidating existing knowledge into a unified sustainability framework, this work offers practical guidance for developing scalable, safe, and environmentally responsible saponin extraction processes aligned with global sustainability priorities. • Saponins have broad health benefits and industrial applications. • ●Conventional extraction methods are inefficient and polluting. • ●Green extraction offers safer, eco-friendly alternatives. • ●Key challenges: scalability, standardization, and impact assessment. • ●Future focus: hybrid methods and sustainable industrial scaling.