Green Extraction of Nephroprotective Phytochemicals for Chronic Kidney Disease: A Pharmacognostic and Pharmacological Review

Abstract

Chronic Kidney Disease (CKD) is a major global health burden characterized by progressive loss of renal function and high morbidity. Traditional pharmacological therapies are often limited by side effects and inadequate disease modification, prompting significant interest in plant-derived bioactive compounds with nephroprotective properties. Recent advances in green extraction technologies — including ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and supercritical fluid extraction (SFE) — offer sustainable, efficient methods to isolate potent phytochemicals while minimizing environmental impact. Green extractions enhance yield and preserve pharmacological integrity of compounds such as flavonoids, polyphenols, terpenoids, and other nephroprotective metabolites, essential for therapeutic development. Importantly, multiple clinical trials and preclinical studies demonstrate that plant-derived bioactive compounds can modulate pathways implicated in CKD pathogenesis, including oxidative stress, inflammation, fibrosis, apoptosis and uremic toxin accumulation. Common nephroprotective agents include curcumin, catechins, rhein, flavonoids, and saponins extracted from species such as Camellia sinensis, Rheum spp., Curcuma longa, and others, which exhibit antioxidant, anti-inflammatory, anti-fibrotic, and renal function-preserving effects. While conventional extraction methods have yielded valuable data, modern green extraction techniques maximize bioactive compound yield and selectivity with reduced organic solvent use and energy consumption, aligning with environmental sustainability goals. This review synthesizes phytochemical profiles of nephroprotective plants, compares green extraction methodologies, and explores the pharmacological mechanisms through which these phytochemicals may mitigate CKD progression. We also discuss challenges including standardization, bioavailability, clinical translation, and regulatory considerations necessary to advance these phytochemicals to therapeutic application. Collectively, green extraction of nephroprotective phytochemicals represents a promising intersection of sustainable technology and evidence-based therapeutics in the management of CKD.