No abstract

We developed a rapid and simple analytical method for the simultaneous determination of seven 3,28-bidesmosidic triterpenoid saponins in the roots of Codonopsis lanceolata. The saponins are lancemaside A, lancemaside B, lancemaside C, lancemaside E, lancemaside G, foetidissimoside A, and aster saponin Hb. Root samples were extracted with 50% methanol and prepared for analysis. Saponins were detected by reversed-phase high-performance liquid chromatography with electrospray ionization mass spectrometry, and ginsenoside Rb(1) was used as an internal standard. The overall recoveries of all saponins were 92-116%, and the relative standard deviation values of intra- and inter-day precision were lower than 3.7 and 7.7%, respectively. Eight root samples collected from Korea and Japan were analyzed using the developed method. Lancemaside A was the most abundant saponin in the root samples from Korea, ranging from 2.65 to 3.64 mg/g dry root. However, the maximum content of lancemaside A among Japanese samples was 0.101 mg/g dry root.

The simple and efficient method for the preparative isolation of lancemaside A along with two other saponins, foetidissimoside A and astersaponin Hb, from the saponin fraction of C. lanceolata was established using CPC.

Lancemaside A, a triterpenoid saponin isolated from the roots of Codonopsis lanceolata, has been reported to ameliorate the reduction of blood testosterone levels induced by immobilization stress in mice. In the present study, we investigated the metabolism and absorption of lancemaside A in mice. After oral administration of lancemaside A at 100 mg/kg body weight, the unmetabolized compound appeared rapidly in plasma (t (max) = 0.5 h). Lancemaside A has a low bioavailability (1.1%) because of its metabolism by intestinal bacteria and its poor absorption in the gastrointestinal tract. Furthermore, we identified four metabolites from the cecum of mice after oral administration of lancemaside A: codonolaside II, echinocystic acid, echinocystic acid 28-O-beta-D: -xylopyranosyl-(1 --> 4)-alpha-L: -rhamnopyranosyl-(1 --> 2)-alpha-L: -arabinopyranosyl ester, and echinocystic acid 28-O-alpha-L: -rhamnopyranosyl-(1 --> 2)-alpha-L: -arabinopyranosyl ester. Among these metabolites, codonolaside II and echinocystic acid were detected in plasma, and their t (max) values were 4 and 8 h, respectively. These findings should be helpful for understanding the mechanism of the biological effect of lancemaside A.

Liquid chromatography coupled with sequential mass spectrometry (LC-MS(n)) has been used to identify 3,28-bidesmosidic triterpenoid saponins, lancemaside A (1), foetidissimoside A (2), aster saponin Hb (3), lancemaside E (4), lancemaside B (5), lancemaside F (6), lancemaside G (7), lancemaside C (8), and lancemaside D (9) in the roots of Codonopsis lanceolata. Structural information about both the aglycone and the sugar moiety at the C-3 position of saponins was obtained in the negative-ion mode. On the other hand, positive-ion spectra mainly provide structural information about the sugar chains of saponins, especially the oligosaccharide moiety at the C-28 position. During subsequent fragmentation of the product ions derived from the oligosaccharide moiety at the C-28 position, fragments produced by sequential loss of a monosaccharide unit were observed. Furthermore, the structural features of two unknown saponins in the roots of C. lanceolata were assigned on the basis of the fragmentation patterns of the known saponins. These studies demonstrate that LC-MS(n) analysis has great potential for the identification and characterization of triterpenoid saponins in plant extracts.

A methanol extract of the leaves of Cephalotaxus harringtonia var. nana and its ethyl acetate (EtOAc)-soluble fraction demonstrated strong antitumor activity against A549 and HT-29 cell lines. The EtOAc-soluble fraction was purified by column chromatography and high-performance liquid chromatography (HPLC) using a reverse-phase column to yield three novel acyl flavonoids and a biflavonoid, along with 15 other known compounds that included flavonoids, biflavonoids, and other phenolics. The structures of the new compounds were elucidated using spectral data from HR-MS and NMR, including two-dimensional NMR studies, as (2R,3R)-3-O-eicosanoyltaxifolin (1), (2R,3R)-3-O-docosanoyltaxifolin (2), (2R,3R)-3-O-tetracosanoyltaxifolin (3), and 6-methyl-4',7,7″-tri-O-methylamentoflavone (4). The isolated compounds, including the known compounds, were tested for possible antitumor activity; some of the biflavones were found to be active. The potent antitumor activity of the extract was attributed to Cephalotaxus alkaloids, such as homoharringtonine (20).