Recent Progress in the Regioselective Biotransformation and Multitarget Therapeutic Potential of Ginsenoside Rd.

Ginsenoside Rd, a protopanaxadiol (PPD)-type tetracyclic triterpenoid saponin, has emerged as a promising bioactive constituent for multitarget therapeutic interventions. However, its natural abundance in the source plant is extremely low, making direct extraction both costly and inefficient. This review systematically summarizes the latest research progress on regioselective biotransformation strategies for Rd production since 2022. Furthermore, it comprehensively reviews recent advances in the diverse pharmacological activities of Rd. Beyond its well-recognized neuroprotective effects against neurological disorders including Alzheimer's disease and Parkinson's disease, we also highlight its antitumor activity and multitarget protective effects in liver diseases. This review provides a theoretical basis for developing Rd as a high-value nutraceutical and therapeutic candidate for systemic health.