Distribution of Sarcophytol A in Soft Coral of the Sarcophyton Genus

The distribution of sarcophytol-A in the Sarcophyton genus was investigated in seven samples belonging to S. glaucum (3 samples), S. infundibulifurme (2 samples), S. crassocaule (1 sample) and S. trocheliophorum (1 sample) that were collected on Ishigaki Island in Okinawa Prefecture. Sarcophytol-A was present in one sample each of S. glaucum and S. infundibulifurme. This study indicates that the composition of cembranoids in the Sarcophyton genus is not related with the respective species, but with the individual samples collected.     

Sequence Analysis of the Mitochondrial Genome of Sarcophyton glaucum: Conserved Gene Order Among Octocorals

The nucleotide sequence for an 11,715-bp segment of the mitochondrial genome of the octocoral Sarcophyton glaucum is presented, completing the analysis of the entire genome for this anthozoan member of the phylum Cnidaria. The genome contained the same 13 protein-coding and 2 ribosomal RNA genes as in other animals. However, it also included an unusual mismatch repair gene homologue reported previously and codes for only a single tRNA gene. Intermediate in length compared to two other cnidarians (17,443 and 18,911 bp), this organellar genome contained the smallest amount of noncoding DNA (428, compared to 1283 and 781 nt, respectively), making it the most compact one found for the phylum to date. The mitochondrial genes of S. glaucum exhibited an identical arrangement to that found in another octocoral, Renilla kolikeri, with five protein-coding genes in the same order as has been found in insect and vertebrate mitochondrial genomes. Although gene order appears to be highly conserved among octocorals, compared to the hexacoral, Metridium senile, few similarities were found. Like other metazoan mitochondrial genomes, the A + T composition was elevated and a general bias against codons ending in G or C was observed. However, an exception to this was the infrequent use of TGA compared to TGG to code for tryptophan. This divergent codon bias is unusual but appears to be a conserved feature among two rather distantly related anthozoans. Received: 27 January 1998 / Accepted: 25 May 1998     

Sarcophytrols G – L,Novel Minor Metabolic Components from South China Sea Soft Coral Sarcophyton trocheliophorum Marenzeller

Minor metabolic components, six new cembranoids sarcophytrols G – L ( 1  –  6 ) along with two known related analogues 7 and 8 , were isolated from the South China Sea soft coral Sarcophyton trocheliophorum. Their structures were elucidated by extensive spectroscopic analyses (1D‐, 2D‐NMR, and ESI‐MS) as well as comparison with literature data. As part of our ongoing research project for discovering bioactive substances from Chinese marine invertebrates, compounds 1  –  8 were tested for their inhibitory activity against protein tyrosine phosphatase 1B (PTP1B), a key target for the treatment of Type‐II diabetes and obesity. However, none of them exhibited potent PTP1B inhibitory activities.     

Mitochondrial DNA of the coral sarcophyton glaucum contains a gene for a homologue of bacterial muts: A possible case of gene transfer from the nucleus to the mitochondrion

The nucleotide sequences of two segments of 6,737 ntp and 258 ntp of the 18.4-kb circular mitochondrial (mt) DNA molecule of the soft coral Sarcophyton glaucum (phylum Cnidaria, class Anthozoa, subclass Octocorallia, order Alcyonacea) have been determined. The larger segment contains the 3′ 191 ntp of the gene for subunit 1 of the respiratory chain NADH dehydrogenase (ND1), complete genes for cytochrome b (Cyt b), ND6, ND3, ND4L, and a bacterial MutS homologue (MSH), and the 5′ terminal 1,124 ntp of the gene for the large subunit rRNA (l-rRNA). These genes are arranged in the order given and all are transcribed from the same strand of the molecule. The smaller segment contains the 3′ terminal 134 ntp of the ND4 gene and a complete tRNA^f-Met gene, and these genes are transcribed in opposite directions. As in the hexacorallian anthozoan, Metridium senile, the mt-genetic code of S. glaucum is near standard: that is, in contrast to the situation in mt-genetic codes of other invertebrate phyla, AGA and AGG specify arginine, and ATA specifies isoleucine. However, as appears to be universal for metazoan mt-genetic codes, TGA specifies tryptophan rather than termination. Also, as in M. senile the mt-tRNA^f-Met gene has primary and secondary structural features resembling those of Escherichia coli initiator tRNA, including standard dihydrouridine and TψC loop sequences, and a mismatched nucleotide pair at the top of the amino-acyl stem. The presence of a mutS gene homologue, which has not been reported to occur in any other known mtDNA, suggests that there is mismatch repair activity in S. glaucum mitochondria. In support of this, phylogenetic analysis of MutS family protein sequences indicates that the S. glaucum mtMSH protein is more closely related to the nuclear DNA-encoded mitochondrial mismatch repair protein (MSH1) of the yeast Saccharomyces cerevisiae than to eukaryotic homologues involved in nuclear function, or to bacterial homologues. Regarding the possible origin of the S. glaucum mtMSH gene, the phylogenetic analysis results, together with comparative base composition considerations, and the absence of an MSH gene in any other known mtDNA best support the hypothesis that S. glaucum mtDNA acquired the mtMSH gene from nuclear DNA early in the evolution of octocorals. The presence of mismatch repair activity in S. glaucum mitochondria might be expected to influence the rate of evolution of this organism's mtDNA. Received: 13 January 1997 / Accepted: 23 September 1997     

Crassocolides G–M,Cembranoids from the Formosan Soft Coral Sarcophyton crassocaule

Seven new polyoxygenated cembranoids possessing an α‐methylene‐γ‐lactone group, crassocolides G–M ( 1 – 7 , resp.), have been isolated from the AcOEt extract of the Formosan soft coral Sarcophyton crassocaule. The structures of compounds 1 – 7 were established by detailed spectroscopic analyses, including 2D‐NMR spectroscopy (¹H,¹H‐COSY, HMQC, HMBC, and NOESY), while the absolute configuration of 1 was determined using a modified reaction of Mosher's method. The cytotoxicity of compounds 1 – 7 against a limited panel of cancer cell lines was also determined.     

Hirsutane sesquiterpenoids from the marine-derived fungus Chondrostereum sp

A new hirsutane sesquiterpenoid, hirsutanol E (1), together with the known compounds hirsutanol A (2) and hirsutanol F (3; gloeosteretriol) were obtained from AcOEt extract of the marine fungus Chondrostereum sp., which was isolated from the soft coral Sarcophyton tortuosum. The structures were elucidated mainly on the basis of the NMR, MS, and X-ray single-crystal diffraction data. Hirsutanol A (2) exhibited potent cytotoxic activities against various cancer cell lines.     

Crassocolides N-P, three cembranoids from the Formosan soft coral Sarcophyton crassocaule

Three new cembranoids crassocolides N-P (1-3), was isolated from the organic extract of a Formosan soft coral Sarcophyton crassocaule. These structures were elucidated on the basis of spectroscopic analyses and by comparison with those previously reported in literature. The cytotoxicity of these compounds toward various cancer cell lines has also been determined.     

中国南海结实肉芝软珊瑚中的一种新鲨肝醇甙

从中国南海西沙群岛附近海域采集的结实肉软珊瑚中分离得到一种新的鲨肝醇甙,命名为结实内之苷。经ＩＲ,ＭＳ＾１Ｈ和＾１３ＣＮＭＲ谱分析和化学转变确定了它的化学结构。     

Terpenes from the Soft Corals Litophyton arboreum and Sarcophyton ehrenbergi

The new cembrane diterpene (3E,11E)‐cembra‐3,8(19),11,15‐tetraene‐7α‐ol ( 1 ), nephthenol ( 2 ), and all‐trans‐peridinin ( 3 ) have been isolated from the soft coral Litophyton arboreum. The tetraterpene 3 , (+)‐7,8‐epoxy‐7,8‐dihydrocembrene C ( 4 ), emblide ( 5 ), sarcophytoxide ( 6 ), sarcoglaucol‐16‐one ( 7 ), guajacophine ( 8 ), and 1,4‐peroxymuurol‐5‐ene ( 9 ) have been obtained from the soft coral Sarcophyton ehrenbergi. The compounds were characterized primarily by NMR spectroscopy. Some of the terpenes were tested for their antiproliferative activity against the cell lines HUVEC and K‐562 and for cytotoxicity against the cell line HeLa, and they showed moderate activities.