Three new flavonol glycosides from the aerial parts of Rodgersia podophylla. (9/29)

Three new flavonol glycosides were isolated together with five known flavonoids and six bergenin derivatives from the aerial parts of Rodgersia podophylla. The structures of these new compounds were elucidated by spectral methods as kaempferol-3-O-alpha-L-5''-acetyl-arabinofuranoside (1), kaempferol 3-O-alpha-L-3''-acetyl-arabinofuranoside (2), and quercetin-3-O-alpha-L-3'',5''-diacetyl-arabinofuranoside (3).  (+info)

Cytotoxicity of triterpenes isolated from Aceriphyllum rossii. (10/29)

Bioassay-guided fractionation of a MeOH extract of the whole plant of Aceriphyllum rossii (Saxifragaceae) led to the isolation of two new triterpenes, 3alpha,23-isopropylidenedioxyolean-12-en-27-oic acid (1) and 23-hydroxy-3-oxoolean-12-en-27-oic acid (2), together with six known triterpenes, 3-oxoolean-12-en-27-oic acid (3), 3alpha-hydroxyolean-12-en-27-oic acid (4), beta-peltoboykinolic acid (5), aceriphyllic acid A (6), oleanolic acid (7), and gypsogenic acid (8). The structures of these compounds were elucidated on the basis of physicochemical and spectroscopic analyses. These compounds were evaluated for in vitro cytotoxicity against the K562 and HL-60 cell lines. Olean-12-en-27-oic acid derivatives (1-6) exhibited considerable cytotoxicity against K562 and HL-60 cell lines with IC(50) values ranging from 12.2 to 28.7 microM and from 12.1 to 25.8 microM, respectively.  (+info)

Replacement of species along altitude gradients: the role of branch architecture. (11/29)

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A yellow chlorophyll catabolite is a pigment of the fall colours. (12/29)

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3-Oxoolean-12-en-27-oic acid isolated from Aceriphyllum rossii induces caspase-8-dependent apoptosis in human promyelocytic leukemia HL-60 cells. (13/29)

In the present study, we investigated the effects of 3-oxoolean-12-en-27-oic acid (3-OA) isolated from the underground parts of Aceriphyllum rossii (Saxifragaceae) on the viability and apoptosis of HL-60 human promyelocytic leukemia cells, and the mechanisms underlying its action. 3-OA-treated HL-60 cells and HeLa human cervix adenocarcinoma cells displayed several apoptotic features, such as, DNA fragmentation, DNA laddering by agarose gel electrophoresis, and hypodiploid DNA contents by flow cytometry, and 3-OA also caused the activations of caspase-8, -9 and -3. Pretreatment with z-VAD-fmk (a broad-caspase inhibitor) almost completely suppressed 3-OA-induced DNA ladder formation and hypodiploid DNA contents, thereby implicating the caspase cascade in the apoptotic process. In addition, z-IETD-fmk (a caspase-8 inhibitor) and z-DEVD-fmk (a caspase-3 inhibitor) also completely neutralized the apoptotic effect of 3-OA in HL-60 cells. Furthermore, 3-OA increased Fas-related protein contents and the mRNA expressions of Fas ligand (FasL), Fas, and Fas-associated death domain (FADD). Preincubation with anti-Fas or anti-FasL blocking antibodies completely prevented 3-OA-induced apoptosis. Taken together, these results suggest that 3-oxoolean-12-en-27-oic acid induces apoptosis by activating caspase-8 via FasL-stimulated death receptor signaling.  (+info)

Population dynamics along a primary succession gradient: do alpine species fit into demographic succession theory? (14/29)

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Unveiling cryptic species diversity of flowering plants: successful biological species identification of Asian Mitella using nuclear ribosomal DNA sequences. (15/29)

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Diversity of floral visitors to sympatric Lithophragma species differing in floral morphology. (16/29)

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