Proteomic characterization and biological activities of the mucus produced by the zoanthid Palythoa caribaeorum (Duchassaing & Michelotti, 1860).

Mucus, produced by Palythoa caribaeorum has been popularly reported due to healing, anti-inflammatory, and analgesic effects. However, biochemical and pharmacological properties of this mucus remains unexplored. Therefore, the present study aimed to study its proteome profile by 2DE electrophoresis and MALDI-TOF. Furthermore, it was evaluated the cytotoxic, antibacterial, and antioxidant activities of the mucus and from its protein extract (PE). Proteomics study identified14 proteins including proteins involved in the process of tissue regeneration and death of tumor cells. The PE exhibited cell viability below 50% in the MCF-7 and S-180 strains. It showed IC50 of 6.9 µg/mL for the J774 lineage, and also, favored the cellular growth of fibroblasts. Furthermore, PE revealed activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Staphylococcus epidermidis (MIC of 250 µg/mL). These findings revealed the mucus produced by Palythoa caribaeorum with biological activities, offering alternative therapies for the treatment of cancer and as a potential antibacterial agent.

Polyoxygenated cembranoids from the South China Sea soft coral Sarcophyton boettgeri and their stereochemistry.

Four new polyoxygenated cembranoids, namely sarcoboettgerol A (1), 12-epi-humilisin D (2), sarcoboettgerol B (3), and sarcoboettgerol C (4), together with one known related analogue, humilisin D (5), were isolated and characterized from the soft coral Sarcophyton boettgeri collected off Ximao island, Hainan Province, China. The structures and absolute configurations of the new compounds were determined by extensive spectroscopic data analyses, Cu kα single crystal X-ray diffraction analysis, and TDDFT-ECD calculations. A plausible biogenetic relationship of 3 and 4 was proposed.

Anti-epileptic Kunitz-like peptides discovered in the branching coral Acropora digitifera through transcriptomic analysis.

Approximately 50 million people are suffering from epilepsy worldwide. Corals have been used for treating epilepsy in traditional Chinese medicine, but the mechanism of this treatment is unknown. In this study, we analyzed the transcriptome of the branching coral Acropora digitifera and obtained its Kyoto Encyclopedia of Genes and Genomes (KEGG), EuKaryotic Orthologous Groups (KOG) and Gene Ontology (GO) annotation. Combined with multiple sequence alignment and phylogenetic analysis, we discovered three polypeptides, we named them AdKuz1, AdKuz2 and AdKuz3, from A. digitifera that showed a close relationship to Kunitz-type peptides. Molecular docking and molecular dynamics simulation indicated that AdKuz1 to 3 could interact with GABAA receptor but AdKuz2-GABAA remained more stable than others. The biological experiments showed that AdKuz1 and AdKuz2 exhibited an anti-inflammatory effect by decreasing the aberrant level of nitric oxide (NO), IL-6, TNF-α and IL-1ß induced by LPS in BV-2 cells. In addition, the pentylenetetrazol (PTZ)-induced epileptic effect on zebrafish was remarkably suppressed by AdKuz1 and AdKuz2. AdKuz2 particularly showed superior anti-epileptic effects compared to the other two peptides. Furthermore, AdKuz2 significantly decreased the expression of c-fos and npas4a, which were up-regulated by PTZ treatment. In addition, AdKuz2 reduced the synthesis of glutamate and enhanced the biosynthesis of gamma-aminobutyric acid (GABA). In conclusion, the results indicated that AdKuz2 may affect the synthesis of glutamate and GABA and enhance the activity of the GABAA receptor to inhibit the symptoms of epilepsy. We believe, AdKuz2 could be a promising anti-epileptic agent and its mechanism of action should be further investigated.

Further new cembranoids from the South China Sea soft coral Sarcophyton trocheliophorum.

Two new cembranoids, ximaosarcophytols A (1) and B (2), together with three related known ones (3-5), were isolated from the soft coral Sarcophyton trocheliophorum collected off the Ximao Island, Hainan Province, China. Their structures including the absolute configurations were elucidated by extensive spectroscopic analysis, TDDFT/ECD (time-dependent density functional theory/electronic circular dichroism) calculations and comparison with the reported data.

Further new nardosinane-type sesquiterpenoids from the Xisha soft coral Litophyton nigrum.

Further chemical investigation of the Xisha soft coral Litophyton nigrum has resulted in the isolation of four new nardosinane-type sesquiterpenoids, namely linardosinenes D-G (1-4). The structures of new compounds were elucidated by extensive analyses of their spectroscopic data and by comparison with the reported data of known related ones. All compounds exhibited weak inhibitory effect against bromodomain-containing protein 4 (BRD4), a promising therapeutic target in various human diseases, at a concentration of 10 µM.

New lobane-type diterpenoids from the Xisha soft coral Sinularia polydactyla.

Lobane-type diterpenoids are not frequently discovered from marine soft corals. In this paper, three new lobane type diterpenes, 13-methoxyloba-8,10,15(16),17(18)-tetraene (1), 8,10,13(15)Z,16E-lobatetraene (2) and 19-hydroxy-lobatetraene (3), and a new natural compound, 17,18-epoxyloba-16-acetoxy-8,10,13(15)-trien (4), co-occurring with a known related diterpenoid, 18-methoxyloba-8,10,13(15),16(17)-tetraene (5), were isolated from the South China Sea soft coral Sinularia polydactyla. The structures of new compounds were determined by extensive spectroscopic analysis and by comparison with those reported in the literature. In bioassay, all the isolates were inactive on antibacterial, PTP1B inhibitory, and immunological activities. This study increased the chemical diversity of marine diterpenoids.

Cytotoxic polyhydroxy sterols from the Egyptian Red Sea soft coral Sarcophyton acutum.

The methanolic extract and its sub-extracts (viz, n-hexane, DCM, EtOAc and MeOH) of the soft coral Sarcophyton acutum were evaluated as anti-Leishmania major and as anticancer (against the HepG2, MCF-7, and A549 cell lines) using the MTT assay. Six polyhydroxy sterols (1-6) were isolated from the most active cytotoxic and anti-leishmanial EtOAc-soluble fraction. Their structures were established as two new polyhydroxy sterols, acutumosterols A (1) and B (2), and four known structural analogues (3-6) by intensive spectroscopic analyses, and by comparison with data of related compounds. Compound 4 exerted noticeable cytotoxicity against HepG2 cell line (IC50 17.2 ± 1.5 µg/mL), while the other pure isolates showed weak to moderate cytotoxicity (24.8 ± 2.8-57.2 ± 5.2). The results were discussed in relation to the structural features of these closely related sterols.

New cytotoxic cembranolides from an Okinawan soft coral, Lobophytum sp.

Three new cembranolides (1-3) were isolated from an Okinawan soft coral, Lobophytum sp., together with the known cembranolide diterpenoids (4-9). Their structures were determined by extensive analysis of spectroscopic data (1D and 2D NMR, IR, and MS), molecular modeling, and comparison with data reported elsewhere. All compounds contain an α-methylene-γ-lactone ring adjacent to a cembrane, and some of them (1, 6-8) have an epoxide ring as well. The new metabolites were evaluated for cytotoxicity against HeLa, A459, B16-F10, and RAW 264.7 cells and anti-inflammatory effect in LPS-stimulated inflammatory RAW 264.7 macrophage cells.

Four new cembranoids from the Chinese soft coral Sinularia sp. and their anti-Aß aggregation activities.

Four new cembranoids (1-4) were isolated from the extracts of a soft coral collected from the sea area near Xisha Island, South China Sea. The structures of these compounds were determined mainly by spectroscopic analyses, with the absolute configuration of 1 being established by X-ray diffraction analysis. In bioassay, compounds 1 and 3 displayed moderate inhibitory activity against Aß42 aggregation (20.6% and 37.2% inhibition at 10 µM). The binding mode of 1 with Aß42 monomer was predicted by molecular docking. In addition, compounds 1 and 3 did not show cytotoxicity against human tumor cell lines (SH-SY5Y, MDA-MB-426, A549, Hep3B, and HT-29) at 100 µM. Taken together, these cembranoids as new anti-Aß aggregation agents derived from Sinularia sp. provided a new chemical scaffold for anti-Alzhemer's disease drug discovery.

Two new cembrane-type diterpenoids from the xisha soft coral Lemnalia flava.

Further chemical investigation of the South China Sea soft coral Lemnalia flava resulted in the isolation and characterization of two new cembranoids, namely, xishaflavalins G and H (1 and 2), along with three known related compounds (3-5). The structures of the new compounds were elucidated by detailed spectroscopic analysis and by the comparison of their spectroscopic data with those reported in the literature. The discovery of cembrane-type diterpenes from soft coral of the genus Lemnalia was reported for the first time. In addition, compound 5 exhibited moderate inhibitory effects on the ConA-induced T lymphocytes and/or lipopolysaccharide (LPS)-induced B lymphocytes proliferation.

Screening of NO Inhibitor Release Activity from Soft Coral Extracts Origin Palu Bay, Central Sulawesi, Indonesia.

BACKGROUND: As a marine organism, soft corals can be utilized to be various bioactive substances, especially terpenoids and steroids. The soft corals family which produces bioactive generally come from clavulariidae, alcyoniidae, nephtheidae and xeniidae family. OBJECTIVE: To investigate the bioactivity of Nitric Oxide (NO) inhibitor release from soft coral crude extracts of Sinularia sp. (SCA), Nephthea sp. (SCB), Sarcophyton sp. (SCC), Sarcophyton sp. (SCD), Sinularia sp. (SCE) and Sinularia sp. (SCF). MATERIALS AND METHODS: Soft coral is collected from Palu Bay (Central Sulawesi). NO inhibitory release activity measured according to the Griess reaction. Soft corals sample macerated with 1:2 (w/v). Then, Soft coral extracts with the best NO Inhibitor activity partitioned with Dichloromethane, Ethyl acetate, and n-butanol. The bioactive of all crude extracts were identified by GC-MS to find compounds with anti-inflammatory potential. RESULTS: Sarcophyton sp. (SCC) and Sinularia sp. (SCF) are able to inhibit NO concentrations of 0.22 ± 0.04 and 0.20 ± 0.04 µM at 20 mg/mL, respectively. The chemical constituents determined and showed the potential as anti-inflammatory in the crude of Sinularia sp. (SCA) were Octacosane (3.25%). In Nephthea sp., (SCB) were Cyclohexene, 6-ethenyl-6- methyl-1-(1-methylethyl)-3-(1-methylethylidene)-,(S)- (0.55%); Azulene, 1,2,3,4,5,6,7,8- octahydro-1,4-dimethyl-7-(1-methylethylidene)-, (1S-cis)- (0.53%); and 1,7,7-Trimethyl- 2-vinylbicyclo[2.2.1]hept-2-ene (4.72%). In Sarcophyton sp, (SCC) were Eicosane (0.12%); Nonacosane (10.7%); 14(ß)-Pregnane (0.87%); Octacosane 6.39%); and Tricosane (1.53%). In Sarcophyton sp. (SCD) were 14(ß)-Pregnane (2.69%); and Octadecane (27.43%). In crude of Sinularia sp. (SCE) were Oleic Acid (0.63%); 7,10-Hexadecadienoic acid, methyl ester (0.54%); 14(ß)-Pregnane (1.07%); 5,8,11,14-Eicosatetraenoic acid, ethyl ester, (all-Z)- (4.60%); Octacosane (7.75%); and 1,2-Benzisothiazole, 3-(hexahydro-1Hazepin- 1-yl)-, 1,1-dioxide (1.23%). In the crude of Sinularia sp., (SCF) were Oxirane, decyl- (1.38%); Nonacosane (0.57%); Cyclohexanol, 5-methyl-2-(1-methylethenyl)- (0.61%); 14B-Pregnane (0.76%); and Tetratriacontane (1.02%). CONCLUSION: The extract of Sarcophyton sp. (SCC) and Sinularia sp. (SCF) showed the best NO inhibitory release activity. This study is making soft corals from Central Sulawesi, Indonesia can become a potential organism in the discovery and development of bioactive substances anti-inflammatory.

New cembrane-type diterpenoids from Bornean soft coral Nephthea sp. with antifungal activity against Lagenidium thermophilum.

Three new cembrane diterpenes, nephthecrassocolides A-B (1-2) and 6-acetoxy nephthenol acetate (3) along with three known compounds, 6-acetoxy-7,8-epoxy nephthenol acetate (4), epoxy nephthenol acetate (5) and nephthenol (6) were isolated from one population of Nephthea sp. Their structures were elucidated based on spectroscopic data analysis and the antifungal activities of compounds 1-6 were evaluated.

Three new capnosane-type diterpenoids from the South China Sea soft coral Lobophytum sp.

Three new diterpenoids with an unusual capnosane skeleton named lobophytrols A-C (1-3) were isolated from the South China Sea soft coral Lobophytum sp. along with one known related diterpene, (11S,12S,1E,3E,7E)-11,12-epoxycembra-1,3,7-triene (7). Their structures were elucidated on the basis of spectroscopic analysis and by comparison with those reported in the literature.

Further new eunicellin-based diterpenoids from the Guangxi Weizhou soft coral Cladiella krempfi.

Three new polyoxygenated diterpenes (1, 3 and 4) of eunicellin-type, namely, 8-n-butyryl-litophynol A, 6-keto-litophynol B and 6-epi-litophynol B, respectively, together with two related known ones (2 and 5), were isolated from the soft coral Cladiella krempfi collected off the Weizhou island, Guangxi Zhuang Autonomous Region, China. The structures of the new compounds were elucidated by extensive spectroscopic analysis and chemical correlation. In bioassay, all the new compounds displayed moderate anti-inflammatory effects.

CO2 storage and release in the deep Southern Ocean on millennial to centennial timescales.

The cause of changes in atmospheric carbon dioxide (CO2) during the recent ice ages is yet to be fully explained. Most mechanisms for glacial-interglacial CO2 change have centred on carbon exchange with the deep ocean, owing to its large size and relatively rapid exchange with the atmosphere1. The Southern Ocean is thought to have a key role in this exchange, as much of the deep ocean is ventilated to the atmosphere in this region2. However, it is difficult to reconstruct changes in deep Southern Ocean carbon storage, so few direct tests of this hypothesis have been carried out. Here we present deep-sea coral boron isotope data that track the pH-and thus the CO2 chemistry-of the deep Southern Ocean over the past forty thousand years. At sites closest to the Antarctic continental margin, and most influenced by the deep southern waters that form the ocean's lower overturning cell, we find a close relationship between ocean pH and atmospheric CO2: during intervals of low CO2, ocean pH is low, reflecting enhanced ocean carbon storage; and during intervals of rising CO2, ocean pH rises, reflecting loss of carbon from the ocean to the atmosphere. Correspondingly, at shallower sites we find rapid (millennial- to centennial-scale) decreases in pH during abrupt increases in CO2, reflecting the rapid transfer of carbon from the deep ocean to the upper ocean and atmosphere. Our findings confirm the importance of the deep Southern Ocean in ice-age CO2 change, and show that deep-ocean CO2 release can occur as a dynamic feedback to rapid climate change on centennial timescales.

Zoanthid mucus as new source of useful biologically active proteins.

Palythoa caribaeorum is a very common colonial zoanthid in the coastal reefs of Brazil. It is known for its massive production of mucus, which is traditionally used in folk medicine by fishermen in northeastern Brazil. This study identified biologically active compounds in P. caribaerum mucus. Crude mucus was collected during low tides by the manual scraping of colonies; samples were maintained in an ice bath, homogenized, and centrifuged at 16,000 g for 1 h at 4 °C; the supernatant (mucus) was kept at -80 °C until use. The enzymatic (proteolytic and phospholipase A2), inhibitory (metallo, cysteine and serine proteases), and hemagglutinating (human erythrocyte) activities were determined. The results showed high levels of cysteine and metallo proteases, intermediate levels of phosholipase A2, low levels of trypsin, and no elastase and chymotrypsin like activities. The mucus showed potent inhibitory activity on snake venom metalloproteases and cysteine proteinase papain. In addition, it showed agglutinating activity towards O+, B+, and A+ erythrocyte types. The hemostatic results showed that the mucus prolongs the aPTT and PT, and strongly inhibited platelet aggregation induced by arachidonic acid, collagen, epinephrine, ADP, and thrombin. The antimicrobial activity was tested on 15 strains of bacteria and fungi through the radial diffusion assay in agar, and no activity was observed. Compounds in P. caribaeorum mucus were analyzed for the first time in this study, and our results show potential pharmacological activities in these compounds, which are relevant for use in physiopathological investigations. However, the demonstration of these activities indicates caution in the use of crude mucus in folk medicine. Furthermore, the present or absent activities identified in this mucus suggest that the studied P. caribaeorum colonies were in thermal stress conditions at the time of sample collection; these conditions may precede the bleaching process in zoanthids. Hence, the use of mucus as an indicator of this process should be evaluated in the future.

15-deoxy-isoxeniolide-A, new diterpenoid from a bornean soft coral, Xenia sp.

A new xenicane diterpenoid, 15-deoxy-isoxeniolide-A (1) along with four known compounds 9-deoxy-isoxeniolide-A (2), isoxeniolide-A (3), xeniolide-A (4) and coraxeniolide-B (5) were isolated from the Bornean soft coral Xenia sp. The structures of these metabolites were elucidated on the basis of spectral analysis, NMR and HRESIMS. Compound 5 showed cytotoxic activity against ATL cell line, S1T.

Flaccidoxide-13-Acetate Extracted from the Soft Coral Cladiella kashmani Reduces Human Bladder Cancer Cell Migration and Invasion through Reducing Activation of the FAK/PI3K/AKT/mTOR Signaling Pathway.

Metastasis of cancer is the cause of the majority of cancer deaths. Active compound flaccidoxide-13-acetate, isolated from the soft coral Cladiella kashmani, has been found to exhibit anti-tumor activity. In this study, Boyden chamber analysis, Western blotting and gelatin zymography assays indicated that flaccidoxide-13-acetate exerted inhibitory effects on the migration and invasion of RT4 and T24 human bladder cancer cells. The results demonstrated that flaccidoxide-13-acetate, in a concentration-dependent manner, reduced the levels of matrix metalloproteinase-2 (MMP-2), MMP-9, urokinase-type plasminogen activator receptor (uPAR), focal adhesion kinase (FAK), phosphatidylinositide-3 kinases (PI3K), p-PI3K, AKT, p-AKT, mammalian target of rapamycin (mTOR), p-mTOR, Ras homolog gene family, member A (Rho A), Ras, mitogen-activated protein kinase kinase 7 (MKK7) and mitogen-activated protein kinase kinase kinase 3 (MEKK3), and increased the expressions of tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 in RT4 and T24 cells. This study revealed that flaccidoxide-13-acetate suppressed cell migration and invasion by reducing the expressions of MMP-2 and MMP-9, regulated by the FAK/PI3K/AKT/mTOR pathway. In conclusion, our study was the first to demonstrate that flaccidoxide-13-acetate could be a potent medical agent for use in controlling the migration and invasion of bladder cancer.

Soft coral Cespitularia stolonifera: New cytotoxic ceramides and gastroprotective activity.

In the present study, a new ceramide, namely 2S, 3R-4E, 8E-2-(heptadecanoylamino)-heptadeca-4, 8-diene-1, 3-diol (1), along with four known steroids, including 24-methylcholesta-5, 24(28)-diene-3ß-ol (2), 24-methylcholesta-5, 24(28)-diene-3ß-acetate (3), 4-methyl-24-methylcholesta-22-ene-3-ol (4), and cholesterol, was isolated and characterized from CH2Cl2/MeOH extract of Cespitularia stolonifera. A new acetate derivative of compound 1, termed 2S, 3R-4E, 8E-2-(heptadecanoylamino)-heptadeca-4, 8-diene-1, 3-diacetate (1a), was also prepared in the present study. All the structures were established on the basis of modern spectroscopic techniques, including FT-IR, 1D, 2D-NMR, HRESI-MS, and GC-MS, in addition of chemical methods. (-)-Alloaromadendren, ledane, (1)-alloaromadendren oxide, isoaromadendrene epoxide and (-)-caryophellen oxide were identified from the n-hexane fraction using GC-MS. The extract and the two ceramides (1) and (1a) exhibited significant cytotoxic activity against lung cancer A549 cells, while the extract and the two steroids (2) and (3) exhibited significant cytotoxic activity against breast cancer MCF-7 cells. The CH2Cl2/MeOH extract exhibited significant antiulcer activity in both ethanol and acetic acid induced ulcer models in rats, as evidenced by histopathological, histochemical, and biochemical examinations.

Briarenol B, a New Polyoxygenated Briarane from the Octocoral Briareum excavatum.

A new polyoxygenated briarane diterpenoid, briarenol B (1), was isolated from the octocoral Briareum excavatun and its structure determined from spectroscopic data. In RAW264.7 cells, a macrophage-like murine cell line, briarane B (1) was found to enhance the protein expression of pro-inflammatory cyclooxygenase (COX-2) and inducible nitric oxide synthase (iNOS) in cells stimulated by lipopolysaccharide (LPS).