Project description:Two novel diterpenoids, sinularbols A (1) and B (2), which were found to possess a new carbon skeleton were isolated from the soft coral Sinularia arborea. The structures of compounds 1 and 2 were elucidated by spectroscopic methods and 2 displayed a moderately inhibitory effect on the generation of superoxide anion by human neutrophils.
Project description:Two new 13-hydroxycembrane diterpenoids, arbolides A (1) and B (2), along with a known trihydroxysteroid, crassarosterol A (3), were isolated from the soft coral Sinularia arborea. The structures of new cembranes 1 and 2 were elucidated by spectroscopic methods. Steroid 3 was found to exhibit cytotoxicity toward K562 and MOLT-4 leukemia.
Project description:Our work provides strong support for the hypothesis that Sinularia flexibilis ingests diatoms such as Thalassiosira pseudonana. We assessed algal ingestion by S. flexibilis through estimates of algal removal, histological analyses, scanning electron microscopy observations, and gene expression determination (18S and silicon transporter 1) by real time PCR. Cell counts are strongly suggestive of algal removal by the coral; light and scanning microscopy provide qualitative evidence for the ingestion of T. pseudonana by S. flexibilis, while molecular markers did not prove to be sufficiently selective/specific to give clear results. We thus propose that previous instances of inability of corals to ingest algae are reconsidered using different technical approach, before concluding that coral herbivory is not a general feature.
Project description:Chemical examination of the Taiwanese soft coral Sinularia flexibilis led to the isolation of five cembrane-based diterpenoids 1-5, including two new metabolites, 11-acetylsinuflexolide (1) and 11-acetyldihydrosinuflexolide (2). The structures of the new metabolites were determined based on extensive spectroscopic analysis, particularly mass spectrometry and 2D NMR (1H-1H COSY, HMQC, HMBC, and NOESY) spectroscopy. Metabolites 1, 3 and 4 exhibited moderate to weak cytotoxicity to human tumor cell lines, HeLa, HEp-2, MCF-7 and MDA-MB-231.
