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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).

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.

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.

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.

Molasses of tangerine orange (Citrus unshiu Markovich) is obtained as a waste product in the course of tangerine orange juice production. This molasses is expected to be a useful source of organic compounds such as flavonoids and limonoids. To elucidate a use for this molasses waste, we isolated and identified its organic constituents. Two new flavanonol glycosides were isolated from tangerine orange molasses, along with several flavonoids such as hesperidine, narirutin, eriodictyol, 3',4',5,6,7,8-hexamethoxy-3-O-beta-D-glucopyranosyloxyflavone, and 3',4',5,6,7,8-hexamethoxy- 3-beta-D-[4-O-(3-hydroxy-3-methylglutaloyl)]-glucopyranosyloxyflavone, and limonoids such as limonin, nomilin, and cyclic peptide, citrusin III. The structures of the new flavanonol glycosides were determined as (2R,3R)-7-O-(6-O-alpha-L-rahmnopyranosyl-beta-D-glucopyranosyl)-aromadendrin and 7-O-(6-O-alpha-L-rahmnopyranosyl-beta-D-glucopyranosyl)-3,3',5,7-tetrahydroxy-4'-methoxyflavanone by means of spectral analyses using (1)H-NMR, (13)C-NMR, and 2D-NMR. Of these compounds, flavanone glycoside, hesperidin and narirutin were isolated as the main constituents. Thus, molasses is a promising source of flavonoid glycosides.