Chemical constituents in soft coral Sarcophyton glaucum were separated and purified by various chromatographic methods. Based on the spectral data, physicochemical properties, and comparison with the data reported in the literature, nine cembranoids, including a new cembranoid named sefsarcophinolide(1) together with eight known cembranoids, namely(+)-isosarcophine(2), sarcomilitatin D(3), sarcophytonolide J(4),(1S,3E,7E,13S)-11,12-epoxycembra-3,7,15-triene-13-ol(5), sarcophytonin B(6),(-)-eunicenone(7), lobophytin B(8), and arbolide C(9), were identified. As revealed by biological activity experiment results, compounds 2-6 had weak acetylcholinesterase inhibitory activity, and compound 5 displayed weak cytotoxicity against K562 tumor cell line.
Animals ; Anthozoa ; Acetylcholinesterase ; Cell Line, Tumor

Marine microorganisms, especially marine fungi, have historically proven their value as a prolific source for structurally novel and pharmacologically active secondary metabolites (Deshmukh et al., 2018; Carroll et al., 2022). The corals constitute a dominant part of reefs with the highest biodiversity, and harbor highly diverse and abundant microbial symbionts in their tissue, skeleton, and mucus layer, with species-specific core members that are spatially partitioned across coral microhabitats (Wang WQ et al., 2022). The coral-associated fungi were very recently found to be vital producers of structurally diverse compounds, terpenes, alkaloids, peptides, aromatics, lactones, and steroids. They demonstrate a wide range of bioactivity such as anticancer, antimicrobial, and antifouling activity (Chen et al., 2022). The genetically powerful genus Emericella (Ascomycota), which has marine and terrestrial sources, includes over 30 species and is distributed worldwide. It is considered a rich source of diverse secondary metabolites with antimicrobial activity or cytotoxicity (Alburae et al., 2020). Notably, Emericella nidulans, the sexual state of a classic biosynthetic strain Aspergillus nidulans, was recently reported as an important source of highly methylated polyketides (Li et al., 2019) and isoindolone-containing meroterpenoids (Zhou et al., 2016) with unusual skeletons.
Animals ; Aspergillus nidulans ; Polyketides/chemistry* ; Anthozoa/microbiology* ; Anti-Infective Agents/pharmacology* ; Alkaloids

Marine fungi are important members of the marine microbiome, which have been paid growing attention by scientists in recent years. The secondary metabolites of marine fungi have been reported to contain rich and diverse compounds with novel structures (Chen et al., 2019). Aspergillus terreus, the higher level marine fungus of the Aspergillus genus (family of Trichocomaceae, order of Eurotiales, class of Eurotiomycetes, phylum of Ascomycota), is widely distributed in both sea and land. In our previous study, the coral-derived A. terreus strain C23-3 exhibited potential in producing other biologically active (with antioxidant, acetylcholinesterase inhibition, and anti-inflammatory activity) compounds like arylbutyrolactones, territrems, and isoflavones, and high sensitivity to the chemical regulation of secondary metabolism (Yang et al., 2019, 2020; Nie et al., 2020; Ma et al., 2021). Moreover, we have isolated two different benzaldehydes, including a benzaldehyde with a novel structure, from A. terreus C23-3 which was derived from Pectinia paeonia of Xuwen, Zhanjiang City, Guangdong Province, China.
Acetylcholinesterase/metabolism* ; Animals ; Anthozoa/microbiology* ; Anti-Inflammatory Agents/pharmacology* ; Aspergillus/chemistry* ; Benzaldehydes/pharmacology* ; Mice ; RAW 264.7 Cells ; Signal Transduction

Aims: Coral diseases have emerged over the last several decades, causing a loss of live coral cover in the Caribbean and Indo-Pacific reefs. Hence, microbiological and disease cultural techniques are commonly used to investigate their causative microbial agents. This is the first study to identify the potential of pathogenic Vibrio spp. isolated from apparently white syndrome (WS) coral disease in Tioman Island Marine Park using biochemical and molecular techniques. Methodology and results: The Vibrio colonies were isolated from 108 samples of WS infected corals (Acropora cytherea and Montipora aequituberculata) including seawater, sediment and algae found adjacent to infected coral colonies. A total of one hundred representative Vibrio isolates were characterized and most of them (n=50) were identified as V. vulnificus, V. alginolyticus and Photobacterium damselae following biochemical analysis. The molecular analysis revealed six Vibrio spp. (V. coralliilyticus, V. hepatarius, V. brasiliensis, V. tubiashi, V. campbellii, V. ishigakensis) and one Photobacterium rosenbergii. Vibrio coralliilyticus isolated from all infected coral samples may be highly responsible for the sign of WS disease. Conclusion, significance and impact of study The findings of this study provide baseline data and information on potential coral pathogens identified in the coastal waters of Tioman Island. Etiological disease study is suggested to validate their severity and virulence factors in the future.
Vibrio--pathogenicity ; Anthozoa

Globally, peptide-based anticancer therapies have drawn much attention. Marine organisms are a reservoir of anticancer peptides that await discovery. In this study, we aimed to identify cytotoxic oligopeptides from Sarcophyton glaucum. Peptides were purified from among the S. glaucum hydrolysates produced by alcalase, chymotrypsin, papain, and trypsin, guided by a methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay on the human cervical cancer (HeLa) cell line for cytotoxicity evaluation. Purification techniques adopted were membrane ultrafiltration, gel filtration chromatography, solid phase extraction (SPE), and reversed-phase high-performance liquid chromatography (RP-HPLC). Purified peptides were identified by de novo peptide sequencing. From papain hydrolysate, three peptide sequences were identified: AGAPGG, AERQ, and RDTQ (428.45, 502.53, and 518.53 Da, respectively). Peptides synthesized from these sequences exhibited cytotoxicity on HeLa cells with median effect concentration (EC₅₀) values of 8.6, 4.9, and 5.6 mmol/L, respectively, up to 5.8-fold stronger than the anticancer drug 5-fluorouracil. When tested at their respective EC₅₀, AGAPGG, AERQ, and RDTQ showed only 16%, 25%, and 11% cytotoxicity to non-cancerous Hek293 cells, respectively. In conclusion, AERQ, AGAPGG, and RDTQ are promising candidates for future development as peptide-based anticancer drugs.
Amino Acid Sequence ; Animals ; Anthozoa/chemistry* ; Antineoplastic Agents/pharmacology* ; Chromatography, Gel ; Chromatography, High Pressure Liquid ; Chromatography, Reverse-Phase ; Cytotoxins/pharmacology* ; Drug Discovery ; HEK293 Cells ; HeLa Cells ; Humans ; Hydrolysis ; Marine Toxins/pharmacology* ; Oligopeptides/pharmacology* ; Solid Phase Extraction ; Tandem Mass Spectrometry

As a crucial signaling molecule, calcium plays a critical role in many physiological and pathological processes by regulating ion channel activity. Recently, one study resolved the structure of the transient receptor potential melastatin 2 (TRPM2) channel from Nematostella vectensis (nvTRPM2). This identified a calcium-binding site in the S2-S3 loop, while its effect on channel gating remains unclear. Here, we investigated the role of this calcium-binding site in both nvTRPM2 and human TRPM2 (hTRPM2) by mutagenesis and patch-clamp recording. Unlike hTRPM2, nvTRPM2 cannot be activated by calcium alone. Moreover, the inactivation rate of nvTRPM2 was decreased as intracellular calcium concentration was increased. In addition, our results showed that the four key residues in the calcium-binding site of S2-S3 loop have similar effects on the gating processes of nvTRPM2 and hTRPM2. Among them, the mutations at negatively charged residues (glutamate and aspartate) substantially decreased the currents of nvTRPM2 and hTRPM2. This suggests that these sites are essential for calcium-dependent channel gating. For the charge-neutralizing residues (glutamine and asparagine) in the calcium-binding site, our data showed that glutamine mutating to alanine or glutamate did not affect the channel activity, but glutamine mutating to lysine caused loss of function. Asparagine mutating to aspartate still remained functional, while asparagine mutating to alanine or lysine led to little channel activity. These results suggest that the side chain of glutamine has a less contribution to channel gating than does asparagine. However, our data indicated that both glutamine mutating to alanine or glutamate and asparagine mutating to aspartate accelerated the channel inactivation rate, suggesting that the calcium-binding site in the S2-S3 loop is important for calcium-dependent channel inactivation. Taken together, our results uncovered the effect of four key residues in the S2-S3 loop of TRPM2 on the TRPM2 gating process.
Animals ; Asparagine/physiology* ; Binding Sites ; Calcium/metabolism* ; Glutamine/physiology* ; HEK293 Cells ; Humans ; Ion Channel Gating/physiology* ; Sea Anemones ; TRPM Cation Channels/physiology*

In the present study, two new trinor-guaiane sesquiterpenes, named clavuridins B (1), and A (2), along with three known sesquiterpenes (3-5), were isolated from the Xisha soft coral Clavularia viridis. Their structures and absolute configurations were determined on the basis of spectroscopic analysis, X-ray diffraction analysis with Cu Kα radiation and by comparison with related model compounds. Compounds 1 and 3-5 were evaluated for their cytotoxic activity.
Animals ; Anthozoa ; chemistry ; Biological Products ; chemistry ; pharmacology ; Magnetic Resonance Spectroscopy ; Molecular Structure ; Sesquiterpenes, Guaiane ; chemistry ; isolation & purification ; pharmacology

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-3β-ol (2), 24-methylcholesta-5, 24(28)-diene-3β-acetate (3), 4-methyl-24-methylcholesta-22-ene-3-ol (4), and cholesterol, was isolated and characterized from CHCl/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 CHCl/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.
A549 Cells ; Acetic Acid ; Animals ; Anthozoa ; chemistry ; Anti-Ulcer Agents ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Biological Products ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Breast Neoplasms ; drug therapy ; Ceramides ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Disease Models, Animal ; Ethanol ; Female ; Humans ; Lung Neoplasms ; drug therapy ; MCF-7 Cells ; Magnetic Resonance Spectroscopy ; methods ; Rats ; Spectroscopy, Fourier Transform Infrared ; methods ; Steroids ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Ulcer ; chemically induced ; drug therapy

This review briefly describes the origin, chemistry, molecular mechanism of action, pharmacology, toxicology, and ecotoxicology of palytoxin and its analogues. Palytoxin and its analogues are produced by marine dinoflagellates. Palytoxin is also produced by Zoanthids (i.e. Palythoa), and Cyanobacteria (Trichodesmium). Palytoxin is a very large, non-proteinaceous molecule with a complex chemical structure having both lipophilic and hydrophilic moieties. Palytoxin is one of the most potent marine toxins with an LD50 of 150 ng/kg body weight in mice exposed intravenously. Pharmacological and electrophysiological studies have demonstrated that palytoxin acts as a hemolysin and alters the function of excitable cells through multiple mechanisms of action. Palytoxin selectively binds to Na(+)/K(+)-ATPase with a Kd of 20 pM and transforms the pump into a channel permeable to monovalent cations with a single-channel conductance of 10 pS. This mechanism of action could have multiple effects on cells. Evaluation of palytoxin toxicity using various animal models revealed that palytoxin is an extremely potent neurotoxin following an intravenous, intraperitoneal, intramuscular, subcutaneous or intratracheal route of exposure. Palytoxin also causes non-lethal, yet serious toxic effects following dermal or ocular exposure. Most incidents of palytoxin poisoning have manifested after oral intake of contaminated seafood. Poisonings in humans have also been noted after inhalation, cutaneous/systemic exposures with direct contact of aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing Cnidarian zoanthids. Palytoxin has a strong potential for toxicity in humans and animals, and currently this toxin is of great concern worldwide.
Acrylamides ; chemistry ; isolation & purification ; toxicity ; Animals ; Anthozoa ; pathogenicity ; physiology ; Dinoflagellida ; pathogenicity ; physiology ; Dogs ; Guinea Pigs ; Haplorhini ; Humans ; Lethal Dose 50 ; Marine Toxins ; chemistry ; isolation & purification ; toxicity ; Mice ; Rabbits ; Rats ; Seaweed ; pathogenicity ; physiology ; Shellfish Poisoning ; physiopathology ; Sodium-Potassium-Exchanging ATPase ; metabolism

Seven guaiane-type sesquiterpenoids, a new compound 6-formyl-5-isopropyl-3-hydroxymethyl-7-methyl-1H-indene (1), a new natural product 5-isopropyl-3, 7-dimethyl-1H-indene-1-one (2), along with five known compounds: guaiazulene (3), 4-formyl-7-isopropyl-10-methylazulene (4), sesquiterpene ketolactone (5), alismoxide (6) and guaia-1 (5), 6-diene (7), were isolated from gorgonian Muriceides collaris collected in South China Sea. Their structures were elucidated on the basis of extensive spectroscopic analysis [MS, IR, 1H NMR, 13C NMR (DEPT), HMQC, HMBC, NOESY] and by comparison of the spectral data with those of the literatures.
Animals ; Anthozoa ; chemistry ; Azulenes ; China ; Sesquiterpenes ; chemistry ; isolation & purification ; Sesquiterpenes, Guaiane