Briavioids E-G, Newly Isolated Briarane-Diterpenoids from a Cultured Octocoral Briareum violaceum

The chemical screening of a cultured soft coral, Briareum violaceum, led to the isolation of eight natural, briarane-related diterpenoids, including three unreported metabolites, briavioids E-G (1-3), and five known briaranes, briacavatolides B (4) and C (5), briaexcavatin L (6), briaexcavatolide U (7) and briarenol K (8). The structures of briaranes 1-8 were established using spectroscopic methods. The absolute configuration of briavioid A (9), obtained in a previous study, was reported for the first time in this study by a single-crystal X-ray diffraction analysis using a copper radiation source. The anti-inflammatory activity of briaranes 1 and 2 and briaranes 4-8 was evaluated by screening their inhibitory ability against the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins in lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells.

Natural Products from Octocorals of the Genus Dendronephthya (Family Nephtheidae)

In this review, 170 natural substances, including steroid, diterpenoid, sesquiterpenoid, peptide, prostaglandin, base, chlorolipid, bicyclolactone, amide, piperazine, polyketide, glycerol, benzoic acid, glycyrrhetyl amino acid, hexitol, pentanoic acid, aminoethyl ester, octadecanone, alkaloid, and a 53-kD allergenic component from octocorals belonging to genus Dendronephthya, were listed. Some of these compounds displayed potential bioactivities.

Novel Caryophyllane-Related Sesquiterpenoids with Anti-Inflammatory Activity from Rumphella antipathes (Linnaeus, 1758)

Two previously undescribed caryophyllane-related sesquiterpenoids, antipacids A (1) and B (2), with a novel bicyclo[5.2.0] core skeleton, and known compound clovane-2β,9α-diol (3), along with rumphellolide L (4), an esterified product of 1 and 3, were isolated from the organic extract of octocoral Rumphella antipathes. Their structures, including the absolute configurations were elucidated by spectroscopic and chemical experiments. In vivo anti-inflammatory activity analysis indicated that antipacid B (2) inhibited the generation of superoxide anions and the release of elastase by human neutrophils, with IC₅₀ values of 11.22 and 23.53 μM, respectively, while rumphellolide L (4) suppressed the release of elastase with an IC₅₀ value of 7.63 μM.

Geographical and temporal origins of Neocaridina species (Decapoda: Caridea: Atyidae) in Taiwan

BACKGROUND

The freshwater species on Taiwan Island have been documented to have originated from mainland China and the Japanese islands from multiple events and by multiple colonization routes. Moreover, the sequences from the mitochondrial DNA cytochrome c oxidase subunit I (COI) have been used for DNA barcoding to identify the species. This study used the COI sequences to identify Neocaridina species in Taiwan and to examine their geographical and temporal origins.

RESULTS

In total, 479 specimens were collected from 35 localities, which covered almost all rivers in Taiwan. In addition, some sequences were downloaded from GenBank. The maximum likelihood (ML) tree displayed that all sequences were sorted into 13 taxa (clades), and all sequences in Taiwan were sorted into four clades. The Bayesian skyline plots revealed that these four Neocaridina species have declined recently in Taiwan.

CONCLUSIONS

All results support that (1) there are four Neocaridina species in Taiwan, which are N. davidi, N. saccam, N. ketagalan and an undescribed Neocaridina species (N. sp.); (2) these four species colonized Taiwan Island in four colonization events; (3) N. sp. colonized Taiwan first; (4) after the island reached its shape, N. ketagalan and N. saccam colonized Taiwan from the Japanese islands and mainland China, respectively; (5) N. davidi colonized northern Taiwan last; and (6) the cyclic glacial and landform changes in East Asia shaped the colonization events and population structures of the Neocaridina species.

New 8-Hydroxybriaranes from the Gorgonian Coral Junceella fragilis (Ellisellidae)

Three new 8-hydroxybriaranes—fragilides R–T (1–3) were obtained from a sea whip gorgonian coral Junceella fragilis. The structures of briaranes 1–3 were elucidated by using spectroscopic methods, including 1D (¹H and ¹³C NMR), 2D (COSY, HSQC, HMBC, and NOESY experiments) NMR studies, and (+)-HRESIMS. Fragilides S and T (2 and 3) are the only briaranes known to possess 8α-hydroxy and 17β-methyl groups, respectively. Briarane 2 exerted an inhibition effect on iNOS release from RAW264.7; a macrophage cell line that originated from a mouse monocyte macrophage, stimulated with lipopolysaccharides.

New Furanocembranoids from Briareum violaceum

Three new furanocembranoids—briaviodiol F (1) and briaviotriols A (2) and B (3)—along with a known analogue, briaviodiol A (4), were obtained from a cultured-type octocoral Briareum violaceum. The structures of cembranoids 1–3 were elucidated by using spectroscopic methods. In vitro study demonstrated that compounds 2 and 4 exerted inhibition effects on inducible nitric oxide synthase (iNOS) release from RAW 264.7, a macrophage cell line that originated from a mouse monocyte macrophage, stimulated with lipopolysaccharides.

[Regulation of hypoxia inducible factor-1α on permeability of vascular endothelial cells and the mechanism]

Objective: To investigate the regulation of hypoxia-inducible factor-1α (HIF-1α) on permeability of rat vascular endothelial cells and the mechanism. Methods: Twelve male Sprague-Dawley rats aged 35 to 38 days were collected and vascular endothelial cells were separated and cultured. The morphology of cells was observed after 4 days of culture, and the following experiments were performed on the 2nd or 3rd passage of cells. (1) Rat vascular endothelial cells were collected and divided into blank control group, negative control group, HIF-1α interference sequence 1 group, HIF-1α interference sequence 2 group, and HIF-1α interference sequence 3 group according to the random number table (the same grouping method below), with 3 wells in each group. Cells in negative control group, HIF-1α interference sequence 1 group, HIF-1α interference sequence 2 group, and HIF-1α interference sequence 3 group were transfected with GV248 empty plasmid, recombinant plasmid respectively containing HIF-1α interference sequence 1, interference sequence 2, and interference sequence 3 with liposome 2000. Cells in blank control group were only transfected with liposome 2000. After transfection of 24 h, expression levels of HIF-1α mRNA and protein of cells in each group were respectively detected by reverse transcription real-time fluorescent quantitative polymerase chain reaction and Western blotting (the same detecting methods below) . The sequence with the highest interference efficiency was selected. (2) Another batch of rat vascular endothelial cells were collected and divided into blank control group, negative control group, and HIF-1α low expression group, with 3 wells in each group. Cells in blank control group were only transfected with liposome 2000, and cells in negative control group and HIF-1α low expression group were respectively transfected with GV248 empty plasmid and low expression HIF-1α recombinant plasmid selected in experiment (1) with liposome 2000. After 14 days of culture, the mRNA and protein expressions of HIF-1α in each group were detected. (3) Another batch of rat vascular endothelial cells were collected and divided into blank control group, negative control group, and HIF-1α high expression group, with 3 wells in each group. Cells in blank control group were transfected with liposome 2000, and cells in negative control group and HIF-1α high expression group were respectively transfected with GV230 empty plasmid and HIF-1α high expression recombinant plasmid with liposome 2000. After 14 days of culture, the mRNA and protein expressions of HIF-1α of cells in each group were detected. (4) After transfection of 24 h, cells of three groups in experiment (1) and three groups in experiment (2) were collected, and mRNA and protein expressions of myosin light chain kinase (MLCK), phosphorylated myosin light chain (p-MLC), and zonula occludens 1 (ZO-1) of cells were detected. Data were processed with one-way analysis of variance and t test. Results: After 4 days of culture, the cells were spindle-shaped, and rat vascular endothelial cells were successfully cultured. (1) The interference efficiencies of HIF-1α of cells in HIF-1α interference sequence 1 group, HIF-1α interference sequence 2 group, and HIF-1α interference sequence 3 group were 47.66%, 45.79%, and 62.62%, respectively, and the interference sequence 3 group had the highest interference efficiency. After transfection of 24 h, the mRNA and protein expression levels of HIF-1α of cells in interference sequence 3 group were significantly lower than those in blank control group (t=18.404, 9.140, P<0.01) and negative control group (t=15.099, 7.096, P<0.01). (2) After cultured for 14 days, the mRNA and protein expression levels of HIF-1α of cells in HIF-1α low expression group were significantly lower than those in blank control group (t=21.140, 5.440, P<0.01) and negative control group (t= 14.310, 5.210, P<0.01). (3) After cultured for 14 days, the mRNA and protein expression levels of HIF-1α of cells in HIF-1α high expression group were significantly higher than those in blank control group (t=19.160, 7.710, P<0.01) and negative control group (t= 19.890, 7.500, P<0.01). (4) After transfection of 24 h, the mRNA expression levels of MLCK and p-MLC of cells in HIF-1α low expression group were significantly lower than those in blank control group (t=2.709, 4.011, P<0.05 or P<0.01) and negative control group (t=2.373, 3.744, P<0.05 or P<0.01). The mRNA expression level of ZO-1 of cells in HIF-1α low expression group was significantly higher than that in blank control group and negative control group (t=4.285, 5.050, P<0.01). The mRNA expression levels of MLCK and p-MLC of cells in HIF-1α high expression group were significantly higher than those in blank control group (t=9.118, 11.313, P<0.01) and negative control group (t=9.073, 11.280, P<0.01). The mRNA expression level of ZO-1 of cells in HIF-1α high expression group was significantly lower than that in blank control group and negative control group (t=2.889, 2.640, P<0.05). (5) After transfection of 24 h, the protein expression levels of MLCK and p-MLC of cells in HIF-1α low expression group were significantly lower than those in blank control group (t=2.652, 3.983, P<0.05 or P<0.01) and negative control group (t=2.792, 4.065, P<0.05 or P<0.01). The protein expression of ZO-1 of cells in HIF-1α low expression group was significantly higher than that in blank control group and negative control group (t=3.881, 3.570, P<0.01). The protein expression levels of MLCK and p-MLC of cells in HIF-1α high expression group were 1.18±0.24 and 0.68±0.22, which were significantly higher than 0.41±0.21 and 0.35±0.14 in blank control group (t=5.011, 3.982, P<0.05 or P<0.01) and 0.43±0.20 and 0.36±0.12 in negative control group (t= 4.880, 3.862, P<0.05 or P<0.01). The protein expression level of ZO-1 of cells in HIF-1α high expression group was 0.08±0.06, which was significantly lower than 0.20±0.09 in blank control group and 0.19±0.09 in negative control group (t=4.178, 3.830, P<0.05 or P<0.01). Conclusions: HIF-1α up-regulates expressions of MLCK and p-MLC and down-regulates expression of ZO-1, thereby increasing the permeability of rat vascular endothelial cells.

Genetic variation of the land-locked freshwater shrimp Caridina pseudodenticulata (Decapoda: Atyidae: Caridina) in Taiwan

Caridina pseudodenticulata is a land-locked freshwater shrimp, which is endemic to North and West Taiwan. It is listed as Vulnerable under criteria A1ce in the IUCN Red List. Our study used mitochondrial DNA fragment sequences of the cytochrome oxidase subunit I (COI) gene to examine its genetic structure. In total, 204 sequences were analyzed from 22 populations, and all 39 haplotypes were identified. Our study (1) found that the genetic diversity within population of this species was similar to that of other land-locked freshwater prawn in Taiwan; (2) displayed that during glaciation, the Taiwan Strait was largely above water, an event which created opportunities for colonization Taiwan and dispersal widely; (3) showed that although the phylogenetic analysis showed the lack of a population genetic structure, the AMOVA and haplotypes distribution pattern revealed geographically divided; (4) indicated that C. pseudodenticulata could across to neighbor rivers through the mouths of rivers, which confluent with each other during floods.

Oxytoxin-2, An Algal-Derived Molecule from a Cultured Mollusc Volvatella vigourouxi

A natural caulerpenyne-derived sesquiterpene, oxytoxin-2 (1), was isolated from a cultured mollusc Volvatella vigourouxi. The structure of 1 was elucidated on the basis of spectroscopic analysis and this compound was suggested to be a diet-derived metabolite from the green alga Caulerpa sertularioides.-This is the first study on the chemical constituents of V. vigourouxi. Oxytoxin-2 (1) was found to inhibit significantly the expression of the pro-inflammatory inducible nitric oxide synthase (iNOS) protein of lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.

Oxytoxin-2, An Algal-Derived Molecule from a Cultured Mollusc Volvatella vigourouxi

A natural caulerpenyne-derived sesquiterpene, oxytoxin-2 (1), was isolated from a cultured mollusc Volvatella vigourouxi. The structure of 1 was elucidated on the basis of spectroscopic analysis and this compound was suggested to be a diet-derived metabolite from the green alga Caulerpa sertularioides. This is the first study on the chemical constituents of V. vigourouxi. Oxytoxin-2 (1) was found to inhibit significantly the expression of the pro-inflammatory inducible nitric oxide synthase (iNOS) protein of lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.

New marine sterols from an algal-bearing gorgonian coral Pinnigorgia sp

Four new marine sterols, (22E,24R)-ergosta-5,22-diene-3β,11α-diol (1), (24S)-ergosta-5-ene-3β,11α-diol (2), 5α,6α-epoxy-23-demethylgorgost-8-ene-3β,7α-diol (3), and 5α,6α-epoxy-23-demethylgorgost-8(14)-ene-3β,7α-diol (4), along with a known metabolite, 23-demethylgorgost-7-ene-3β,5α,6β-triol (5), were isolated from an algal-bearing gorgonian coral Pinnigorgia sp., collected off the waters of Taiwan. The structures of these sterols were elucidated on the basis of spectroscopic methods. Sterols 1-5 were tested for in vitro cytotoxicity in hepatic stellate cells (HSCs). Proliferation of HSCs plays a key role in the pathogenesis of liver fibrosis.

Persistent organic pollutants in the Antarctic coastal environment and their bioaccumulation in penguins

Persistent organic pollutants (POPs), including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), polybrominated biphenyls (PBBs), and polybrominated diphenyl ethers (PBDEs), have been identified in penguins, lichens, soils, and ornithogenic soils in the Antarctic coastal environment in this study. To the best of our knowledge, no previous study has reported PBDD/F and PBB data from Antarctica. The POP mass contents in penguins were in the following order: PCBs >> PBDEs >> PCDD/Fs; PCBs were the dominant pollutants (6310-144,000 pg/g-lipid), with World Health Organization toxic equivalency values being 2-14 times higher than those of PCDD/Fs. Long-range atmospheric transport is the most primary route by which POPs travel to Antarctica; however, local sources, such as research activities and penguin colonies, also influence POP distribution in the local Antarctic environment. In penguins, the biomagnification factor (BMF) of PCBs was 61.3-3760, considerably higher than that for other POPs. According to BMF data in Adélie penguins, hydrophobic PBDE congeners were more biomagnified at log Kow > 6, and levels decreased at log Kow > 7.5 because larger molecular sizes inhibited transfer across cell membranes.

Pubinernoid A and Apo-9′-fucoxanthinone, Secondary Metabolites from a Gorgonian Coral Pinnigorgia sp

The structures of pubinernoid A (1) and apo-9′-fucoxanthinone (2), isolated from a gorgonian coral Pinnigorgia sp., were elucidated on the basis of spectroscopic analysis and by comparison of their spectroscopic data with those of known compounds. This is the first report of 1 and 2 from an animal source. Apo-9′-fucoxanthinone (2) displayed a significant inhibitory effect on the release of elastase by human neutrophils, with an IC50 value of 5.75 μM.

Pubinernoid A and Apo-9'-fucoxanthinone, Secondary Metabolites from a Gorgonian Coral Pinnigorgia sp

The structures of pubinernoid A (1) and apo-9'-fucoxanthinone (2), isolated from a gorgonian coral Pinnigorgia sp., were elucidated on the basis of spectroscopic analysis and by comparison of their spectroscopic data with those of known compounds. This is the first report of 1 and 2 from an animal source. Apo-9'-fucoxanthinone (2) displayed a significant inhibitory effect on the release of elastase by human neutrophils, with an IC50 value of 5.75 μM.

Different strategies of energy storage in cultured and freshly isolated Symbiodinium sp

The endosymbiotic relationship between cnidarians and Symbiodinium is critical for the survival of coral reefs. In this study, we developed a protocol to rapidly and freshly separate Symbiodinium from corals and sea anemones. Furthermore, we compared these freshly-isolated Symbiodinium with cultured Symbiodinium to investigate host and Symbiodinium interaction. Clade B Symbiodinium had higher starch content and lower lipid content than those of clades C and D in both freshly isolated and cultured forms. Clade C had the highest lipid content, particularly when associated with corals. Moreover, the coral-associated Symbiodinium had higher protein content than did cultured and sea anemone-associated Symbiodinium. Regarding fatty acid composition, cultured Symbiodinium and clades B, C, and D shared similar patterns, whereas sea anemone-associated Symbiodinium had a distinct pattern compared coral-associated Symbiodinium. Specifically, the levels of monounsaturated fatty acids were lower than those of the saturated fatty acids, and the level of polyunsaturated fatty acids (PUFAs) were the highest in all examined Symbiodinium. Furthermore, PUFAs levels were higher in coral-associated Symbiodinium than in cultured Symbiodinium. These results altogether indicated that different Symbiodinium clades used different energy storage strategies, which might be modified by hosts.

New Scalarane Sesterterpenoids from the Formosan Sponge Ircinia felix

Five new scalarane sesterterpenoids, felixins A–E (1–5), were isolated from the Formosan sponge Ircinia felix. The structures of scalaranes 1–5 were elucidated on the basis of spectroscopic analysis. Cytotoxicity of scalaranes 1–5 against the proliferation of a limited panel of tumor cell lines was evaluated.

Trocheliolide A, a Hydroperoxycembranoidal Diterpene from the Octocoral Sarcophyton trocheliophorum

A new hydroperoxycembranoidal diterpene, trocheliolide A (1), was isolated from the octocoral Sarcophyton trocheliophorum. The structure of 1 was elucidated on the basis of spectroscopic and mass spectrometric methods.

Briarenolides K and L, new anti-inflammatory briarane diterpenoids from an octocoral Briareum sp. (Briareidae)

Two new briarane-type diterpenoids, briarenolides K (1) and L (2), were isolated from an octocoral identified as Briareum sp. The structures of new briaranes 1 and 2 were elucidated by spectroscopic methods. In the in vitro anti-inflammatory effects test, briaranes 1 and 2 were found to significantly inhibit the accumulation of the pro-inflammatory iNOS protein of the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.

Rumphellaoic acid A, a novel sesquiterpenoid from the formosan gorgonian coral Rumphella antipathies

A novel sesquiterpenoid, rumphellaoic acid A (1), was isolated from the gorgonian coral Rumphella antipathies, and was found to possess a carbon skeleton that was obtained for the first time from a natural sources. The structure of 1 was elucidated by spectroscopic methods and this compound and was found to exert a moderate inhibitory effect on the release of elastase by human neutrophils.

The identification of the biological characteristics of human ovarian cancer stem cells

OBJECTIVE

Identifying the biological characteristics of previously screened ovarian cancer cell line HO8910-derived stem cells.

MATERIALS AND METHODS

The pre-screening of ovarian cancer cell line HO8910-derived stem cells were subcultured (HO8910 cells were used as a control group) in serum-free medium. Firstly, the capacities of forming spheroids and self-renewal were observed. Then ovarian cancer stem cells (CSCs) were seeded in medium containing serum and cultured to observe the changes in their ability to differentiate. The stem cell-specific markers were also tested. Secondly, we tested the sensitivity of stem cells to cisplatin, doxorubicin, and mitoxantrone using drug susceptibility test. Finally, we inoculated the ovarian CSCs after passaging from culturing in serum-free media to NOD/SCID (non-obese diabetic/severe combined immunodeficient mice) mice in order to observe the tumorigenicity in vivo.

RESULTS

Ovarian CSCs cultured in serum-free medium are capable of forming stable passaged cells spheres and have strong ability of self-renewal and differentiation. Under the condition of serum-free medium culture, the expression levels of CDl33+, CD117+, ABCG2, Nanog, Oct4, and BCRP in ovarian cancer stem cell are significantly higher than the counterparts in HO8910 cells. With the increase of the ability of differentiation, the stem cell marker expression levels reduced. While the differentiation, potential marker-E-cadherin expression levels were significantly lower than the control group. With the increase of the ability to differentiate, E-cadherin expression level was increased. Ovarian CSCs have significant resistance to cisplatin, doxorubicin, and mitoxantrone. NOD/SCID nude mice experiments showed that ovarian cancer stem cell tumorigenicity was significantly higher than control cells and has a continuous tumorigenicity.

CONCLUSIONS

Comparing ovarian CSCs derived from HO8910 to HO8910 cells, the stem cells have significantly enhanced abilities of self-renewal, differentiation, in vivo tumorigenicity, highly expressed stem cell genes, and multidrug resistance.

The complete mitochondrial genome of Holland's spinibarbel Spinibarbus hollandi Oshima (Cypriniformes, Cyprinidae)

In this study, the complete mitogenome sequence of cyprinid fish, Holland's spinibarbel Spinibarbus hollandi Oshima (1919) (Cypriniformes, Cyprinidae, Barbinae) has been amplified and sequenced by employing long polymerase chain reaction method. The mitogenome, consisting of 16,523 base pairs (bp), had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes, and a non-coding control region (CR). CR of 867 bp length is located between tRNA(Pro) and tRNA(Phe). The overall base composition of S. hollandi is 31.87% for A, 26.56% for C, 25.89% for T, and 15.68% for G, with a slight AT bias of 57.76%. The complete mitogenome may provide rather essential and important DNA molecular data for further phylogenetic analysis for not only congeneric species but also higher different taxa of Cyprinid fishes.

Rumphellaones B and C, new 4,5-seco-caryophyllane sesquiterpenoids from Rumphellan antipathies

Two new 4,5-seco-caryophyllane sesquiterpenoids, rumphellaones B (1) and C (2), which were found to possess unprecedented γ-lactone moieties, were obtained from the gorgonian coral Rumphella antipathies. The structures of 1 and 2 were elucidated by spectroscopic methods and compound 2 was found to display modest inhibitory effects on the generation of superoxide anions and the release of elastase by human neutrophils at a concentration of 10 μg/mL.

Cladieunicellin J, a new hydroperoxyeunicellin from cladiella sp

A new 6-hydroperoxyeunicellin diterpenoid, designated as cladieunicellin J (1), was isolated from an octocoral Cladiella sp., and its structure elucidated by spectroscopic methods. Compound 1 was found to exhibit cytotoxicity toward CCRF-CEM human T-cell acute lymphoblastic leukemia.

Cladieunicellin J, a New Hydroperoxyeunicellin from Cladiella sp

A new 6-hydroperoxyeunicellin diterpenoid, designated as cladieunicellin J (1), was isolated from an octocoral Cladiella sp., and its structure elucidated by spectroscopic methods. Compound 1 was found to exhibit cytotoxicity toward CCRF-CEM human T-cell acute lymphoblastic leukemia.

Fatty acid and phospholipid syntheses are prerequisites for the cell cycle of Symbiodinium and their endosymbiosis within sea anemones

Lipids are a source of metabolic energy, as well as essential components of cellular membranes. Although they have been shown to be key players in the regulation of cell proliferation in various eukaryotes, including microalgae, their role in the cell cycle of cnidarian-dinoflagellate (genus Symbiodinium) endosymbioses remains to be elucidated. The present study examined the effects of a lipid synthesis inhibitor, cerulenin, on the cell cycle of both cultured Symbiodinium (clade B) and those engaged in an endosymbiotic association with the sea anemone Aiptasia pulchella. In the former, cerulenin exposure was found to inhibit free fatty acid (FFA) synthesis, as it does in other organisms. Additionally, while it also significantly inhibited the synthesis of phosphatidylethanolamine (PE), it did not affect the production of sterol ester (SE) or phosphatidylcholine (PC). Interestingly, cerulenin also significantly retarded cell division by arresting the cell cycles at the G₀/G₁ phase. Cerulenin-treated Symbiodinium were found to be taken up by anemone hosts at a significantly depressed quantity in comparison with control Symbiodinium. Furthermore, the uptake of cerulenin-treated Symbiodinium in host tentacles occurred much more slowly than in untreated controls. These results indicate that FFA and PE may play critical roles in the recognition, proliferation, and ultimately the success of endosymbiosis with anemones.

Natural product chemistry of gorgonian corals of the family Plexauridae distributed in the Indo-Pacific Ocean

The structures, names, bioactivities and references of 105 natural products obtained from gorgonian corals belonging to the family Plexauridae with an Indo-Pacific distribution are described in this review. All compounds mentioned in this review were obtained from gorgonian corals belonging to the genera Astrogorgia, Bebryce, Echinomuricea, Euplexaura and Menella.

Environmental influence on coastal phytoplankton and zooplankton diversity: a multivariate statistical model analysis

In a marine ecosystem, the diversity of phytoplankton can influence the diversity of zooplankton, or vice versa, and both can be affected by the environmental factors. In this study, we used principal component analysis (PCA) to identify the major sources of influence on the coastal water near an industrial park, following by construction of structural equation model (SEM) to determine the direct and indirect effect of the factors on phytoplankton and zooplankton diversity. PCA results indicated that the coastal area was mainly affected by riverine discharge (represented by high PC factor loadings of transparency and turbidity) and seasonal change (represented by temperature). SEM further suggested that both riverine discharge and seasonal influences can directly affect phytoplankton diversity, but indirectly affected zooplankton diversity via changes in phytoplankton. Using PCA to determine the sources of influence followed by construction of SEM allowed us to understand the relative importance of the environmental factors, direct or indirect, on phytoplankton and zooplankton diversity. When environmental changes occur, a new SEM could be constructed using the same category of physical and biological data and then compared to the current model to verify whether the environmental changes were the cause of alterations in planktonic communities in the area.

Assessment of metabolic modulation in free-living versus endosymbiotic Symbiodinium using synchrotron radiation-based infrared microspectroscopy

The endosymbiotic relationship between coral hosts and dinoflagellates of the genus Symbiodinium is critical for the growth and productivity of coral reef ecosystems. Here, synchrotron radiation-based infrared microspectroscopy was applied to examine metabolite concentration differences between endosymbiotic (within the anemone Aiptasia pulchella) and free-living Symbiodinium over the light-dark cycle. Significant differences in levels of lipids, nitrogenous compounds, polysaccharides and putative cell wall components were documented. Compared with free-living Symbiodinium, total lipids, unsaturated lipids and polysaccharides were relatively enriched in endosymbiotic Symbiodinium during both light and dark photoperiods. Concentrations of cell wall-related metabolites did not vary temporally in endosymbiotic samples; in contrast, the concentrations of these metabolites increased dramatically during the dark photoperiod in free-living samples, possibly reflecting rhythmic cell-wall synthesis related to light-driven cell proliferation. The level of nitrogenous compounds in endosymbiotic cells did not vary greatly across the light-dark cycle and in general was significantly lower than that observed in free-living samples collected during the light. Collectively, these data suggest that nitrogen limitation is a factor that the host cell exploits to induce the biosynthesis of lipids and polysaccharides in endosymbiotic Symbiodinium.

Lobocrassins A-E: new cembrane-type diterpenoids from the soft coral Lobophytum crassum

Five new cembrane-type diterpenoids, lobocrassins A-E (1-5), were isolated from the soft coral Lobophytum crassum. The structures of cembranes 1-5 were established by spectroscopic and chemical methods and by comparison of the spectral data with those of known cembrane analogues. Lobocrassin A (1) is the first cembranoid possessing an α-chloromethyl-α-hydroxy-γ-lactone functionality and is the first chlorinated cembranoid from soft corals belonging to the genus Lobophytum. Lobocrassins B (2) and C (3) were found to be the stereoisomers of the known cembranes, 14-deoxycrassin (6) and pseudoplexaurol (7), respectively. Lobocrassin B (2) exhibited modest cytotoxicity toward K562, CCRF-CEM, Molt4, and HepG2 tumor cells and displayed significant inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils.

Lipid bodies in coral-dinoflagellate endosymbiosis: proteomic and ultrastructural studies

Gastrodermal lipid bodies (LBs) are organelles involved in the regulation of the mutualistic endosymbiosis between reef-building corals and their dinoflagellate endosymbionts (genus Symbiodinium). As their molecular composition remains poorly defined, we herein describe the first gastrodermal LB proteome and examine in situ morphology of LBs in order to provide insight into their structure and function. After tissue separation of the tentacles of the stony coral Euphyllia glabrescens, buoyant LBs of the gastroderm encompassing a variety of sizes (0.5-4 μm in diameter) were isolated after two cycles of subcellular fractionation via stepwise sucrose gradient ultracentrifugation and detergent washing. The purity of the isolated LBs was demonstrated by their high degree of lipid enrichment and as well as the absence of contaminating proteins of the host cell and Symbiodinium. LB-associated proteins were then purified, subjected to SDS-PAGE, and identified by MS using an LC-nano-ESI-MS/MS. A total of 42 proteins were identified within eight functional groups, including metabolism, intracellular trafficking, the stress response/molecular modification and development. Ultrastructural analyses of LBs in situ showed that they exhibit defined morphological characteristics, including a high-electron density resulting from a distinct lipid composition from that of the lipid droplets of mammalian cells. Coral LBs were also characterized by the presence of numerous electron-transparent inclusions of unknown origin and composition. Both proteomic and ultrastructural observations seem to suggest that both Symbiodinium and host organelles, such as the ER, are involved in LB biogenesis.

Cladieunicellins A-E, new eunicellins from an Indonesian soft coral Cladiella sp

Five new eunicellin-type diterpenoids, cladieunicellins A-E (1-5), were isolated from an Indonesian soft coral identified as Cladiella sp. The structures of diterpenoids 1-5 were established using spectroscopic methods. Eunicellins 2 and 5 were found to be cytotoxic against DLD-1 and HL-60 tumor cells, respectively, and 3 displayed inhibitory effects against superoxide anion generation by human neutrophils.

Cladielloides A and B: new eunicellin-type diterpenoids from an Indonesian octocoral Cladiella sp

Two new eunicellin-type diterpenoids, cladielloides A (1) and B (2), which were found to possess a 2-hydroxybutyroxy group in their structures, were isolated from an Indonesian octocoral identified as Cladiella sp. The structures of eunicellins 1 and 2 were elucidated by spectroscopic methods. Cladielloide B (2) exhibited moderate cytotoxicity toward CCRF-CEM tumor cells and this compound displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils.