In vivo anti-inflammatory activity of saponins from Bupleurum rotundifolium

Seven oleanane-type triterpene saponins were isolated from the methanolic extract of the aerial parts of Bupleurum rotundifolium. They were identified on the basis of their spectral data as 3-O-[alpha -L-rhamnopyranosyl (1-->2)-beta -D-glucopyranosyl (1-->2)-beta -D-glucopyranosyl]-28-O-[beta -D-glucopyranosyl (1-->2)-beta -D-glucopyranosyl] echinocystic acid (saponin 1), 3-O-[alpha -L-rhamnopyranosyl (1-->2)-beta -D-glucopyranosyl (1-->2)-beta -D-fucopyranosyl] 11-methoxy-primulagenin A (saponin 2), rotundioside E (saponin 3), rotundioside F (saponin 4), 3 beta -sulfate, 28-O-[beta -D-glucopyranosyl (1-->6)-beta -D-glucopyranosyl. (1-->2)-beta -D-glucopyranosyl (1-->2)-beta -D-glucopyranosyl] ester of primulagenin A (saponin 5), rotundioside C (saponin 6) and 3-O-[alpha -L-rhamnopyranosyl (1-->2)-beta -D-glucopyranosyl (1-->2)-beta -D-fucopyranosyl] 11-methoxy-16 beta ,21 alpha ,28-trihydroxyolean-12-ene (saponin 7). All these saponins proved to be effective against TPA-induced ear edema in mice. Their ID,, were determined to be 248, 288, 128, 99 and 297 nmol/ear for saponin 1, 2, 3, 4 and 6, respectively. Saponins 3 and 6 were also active on a TPA multiple-dose model of skin chronic inflammation. (C) 2001 Elsevier Science Inc. All rights reserved.