Antinociceptive activity of Quillaja saponaria Mol. saponin extract, quillaic acid and derivatives in mice

Abstract Ethnopharmacological relevance Quillaja saponaria bark contains a high percentage of triterpene saponins and has been used for centuries as a cleansing and analgesic agent in Chilean folk medicine. Aim of the study The topical and systemic analgesic effects of a commercial partially purified saponin extract, 3β,16α-dihydroxy-23-oxoolean-12-en-28-oic acid (quillaic acid), methyl 3β,16α-dihydroxy-23-oxoolean-12-en-28-oate and methyl 4-nor-3,16-dioxoolean-12-en-28-oate. Materials and methods The samples were assessed in mice using the topical tail-flick and i.p. hot-plate tests, respectively. Results All the samples showed activity in both analgesic tests in a dose-dependent manner. The most active against tail flick test was commercial partially purified saponin extract (EC50 27.9 mg%, w/v) and more than the ibuprofen sodium. On hot-plate test, methyl 4-nor-3, 16-dioxoolean-12-en-28-oate was the most active (ED50 12.2 mg/kg) and more than the ibuprofen sodium. Conclusions The results of the present study demonstrated that Quillaja saponaria saponins, quillaic acid, its methyl ester, and one of the oxidized derivatives of the latter, elicit dose-dependent antinociceptive effects in two murine thermal models.