Phytochemical and Pharmacological Studies of Natural Saponins from Platycodon grandiflorum

Platycodon grandiflorum (Jacq.) A.DC is a perennial single-species herb in the Campanulaceae family, and its dried roots have been widely used for a long time to diffuse the lung, soothe the throat, dispel phlegm, and expel pus as a Chinese traditional medicine. In addition, P. grandiflorum compounds are homologous to those in medicines and foods approved by the Ministry of Health of China, and many related foods have been marketed. It has been reported that the glycosides in pentacyclic triterpenoids, also known as saponins, are the main biologically active constituents of P. grandiflorum. This article offers a systematic review of recently reported saponins isolated from P. grandiflorum over the past decade covering the literature from the beginning of 2017 through the end of 2022 and describes their structural diversity and pharmacological studies. To the best of our knowledge, a total of 74 natural saponins have been isolated to date. For this review, 131 references on saponins were obtained, and the information from these articles is compiled herein. This review may be of interest to pharmacognosists and natural-product chemists. This review provides new ideas for the development and utilization of natural saponins for clinical applications in the future.