Search Results (350)

Microorganisms provide critical lead compounds for drug development, yet most biosynthetic gene clusters remain silent under standard culture conditions. The OSMAC strategy activates these clusters by adjusting cultivation parameters, thereby enabling the discovery of novel compounds from a single strain. Here, we applied OSMAC to explore the metabolic potential of the soft coral-derived fungus Aspergillus sclerotiorum SCSIO 41031. Three different culture media were employed for the large-scale fermentation process. After isolation by chromatography, the compounds were structurally characterized using NMR, MS, and X-ray single-crystal diffraction, and their absolute configurations were determined by electronic circular dichroism (ECD) calculations. In total, three new compounds, named 6,6′-diacetyl-1,1′-dihydroxy-3,3′-dimethoxydibenzyl ether (1), esterwortmannolol (17) and pestalpolyol I (20), along with 19 known compounds (2–16, 18–19 and 21–22) were obtained. This study validates the efficacy of the OSMAC strategy and underscores that A. sclerotiorum SCSIO 41031 serves as a valuable resource for producing structurally diverse natural products with potent biological activities. Full article

Six new diterpenoids, including two verticillane ghardaqenoids A–B (1–2) and four dolabellane ghardaqenoids C–F (3–6), were isolated from the soft coral Heteroxenia ghardaqensis collected in the South China Sea. The structures of ghardaqenoids A, D, and E (1, 4, 5) were determined by X-ray diffraction. Ghardaqenoids B, C, and F (2, 3, 6) were identified on the basis of NMR data, DP4+, and ECD spectral data. In particular, compound 6 exhibited strong in vitro lipid-lowering activity in free fatty acid (FFA)-induced HepG2 cells and liver organoids. Further mechanistic studies revealed that compound 6 regulated AMPK-related proteins and genes, thereby inhibiting the accumulation of triglycerides (TG) and total cholesterol (TC). These findings suggested that pharmacological AMPK activation serves as a promising role in lipid-lowering therapeutic strategies. Full article

In this study, we used a culture-dependent approach to explore the biochemical potential of bacteria associated with two genera of soft corals collected from the Red Sea (phylum Cnidaria, class Anthozoa, subclass Octocorallia, order Alcyonaceae, and family Alcyoniidae). The soft corals were identified as Cladiella sp. and Paralemnalia sp. The associated bacteria were isolated on marine agar, nutrient agar, starch casein agar, ISP2 Agar, and M1 agar. The highest proportion of strains was recovered using marine agar, followed by nutrient agar and M1. We focused on Gram-positive bacteria and evaluated their cytotoxicity and antimicrobial activity. About 24% of the bacterial samples demonstrated promising cytotoxicity against Ehrlich ascites carcinoma (EAC). Out of 12 bioactive isolated strains, two bacterial isolates showed strong cytotoxicity, with IC₅₀ values of 134.47 and 148.5 µg/mL, respectively. Nine isolates displayed significant antimicrobial activity against two tested pathogens. Based on the 16S rRNA gene sequence, two bioactive bacterial isolates were identified as Bacillus subtilis and Microbacterium sp. These findings indicate that bacteria associated with soft corals could be a valuable source of new bioactive compounds with potential uses in drug development. Furthermore, our data add important insights to the understudied field of host-microbiome relationships in soft corals. Full article

Eight previously unreported cembranoids (1–8), along with four known ones (9–12), have been isolated and identified from the soft coral Lobophytum crissum collected from the South China Sea under the guidance of HSQC-based DeepSAT analysis for targeted isolation. The structures of the new compounds were determined by comprehensive spectroscopic analysis, QM-NMR, TDDFT-ECD calculations, and comparison with reported literature data from analogs. In in vitro bioassays, all the isolated compounds have been screened for their antibacterial and antiproliferative activities. Full article

The first systematic chemical investigation on Sinularia mollis resulted in the isolation and identification of 36 seven-membered cembranolides, including 14 new compounds named sinumollolides A–N (1–14) and 22 known analogs (15–36) by HSQC-based small molecule accurate recognition technology (SMART). Their structures were characterized by spectroscopic methods (1D/2D NMR and UV), HRESIMS, quantum chemical calculations (DP4+ analysis and ECD calculations), and X-ray diffraction analysis. In zebrafish assays, compounds 1, 2, 4, and 5 exhibited anti-inflammatory activity at 20 μM by inhibiting the number of macrophages around the neuromasts, with inhibition rates ranging from 30.4% to 45.6%. Moreover, the two most bioactive and less toxic compounds, 1 and 5, featuring a 14-membered macrocyclic lactone scaffold with several hydroxyl groups and a seven-membered α, β-unsaturated lactone moiety, can inhibit inflammation by suppressing the secretion of inflammatory cytokines at 10 μM in LPS-stimulated BV-2 cells. Full article

Two previously undescribed highly oxygenated cembrane-type diterpenes, namely sarcocraol A (1) and sarcocraol B (2), along with five known compounds (3–7), have been isolated from the soft coral Sarcophyton crassocaule collected off Ximao Island in the South China Sea. Their structures were determined through comprehensive spectroscopic analysis, QM-NMR calculations, TDDFT-ECD computation, X-ray diffraction analysis, and by comparison with literature data. Plausible biosynthetic pathways for these compounds were also proposed. All compounds were evaluated for peroxisome proliferator-activated receptors (PPARs) transcriptional activity using luciferase assay. The bioassay results demonstrated that compound 1 exhibits selective PPAR-γ agonistic activity. Furthermore, it promoted glucose uptake in HepG2 cells by 1.18-, 1.45-, and 1.90-fold at concentrations of 2.5, 5, and 10 μM, respectively, whereas rosiglitazone (10 μM) produced a 2.47-fold increase over the induced control. Compound 1 at 10 μM induced mild lipid accumulation in 3T3-L1 cells, showing a 1.63-fold increase relative to the control, which was much lower than the 3.28-fold increase observed in rosiglitazone (10 μM) group indicating its potential antidiabetic properties. These findings suggested that compound 1 could be a promising lead for the development of antidiabetic agents. Full article

Cembrane-type diterpenoids (cembranoids), natural compounds derived from soft coral Sclerophytum flexibile, exhibit diverse biological activities including anti-inflammatory, anti-cancer, and anti-viral effects. Our previous research demonstrated that Sinulariolide, a member of this group, effectively inhibits TGF-β-induced IL-6 secretion, thereby suppressing inflammation-associated cancer development. Building on these findings, the present study employs a structure-activity relationship (SAR) approach to compare the anti-inflammatory properties of various cembranoids extracted from cultured soft coral Sclerophytum flexibile—a sustainable and environmentally friendly source that offers a consistent supply for research and therapeutic development. By isolating multiple cembrane-type analogs and analyzing their structural differences, we identified key chemical features that enhance their ability to interfere with TGF-β signaling and subsequent IL-6 production. The SAR analysis revealed distinct variations in anti-inflammatory efficacy among the tested compounds, pinpointing structural motifs crucial for inhibiting TGF-β-induced IL-6 secretion. These insights deepen our understanding of the molecular basis behind the anti-inflammatory action of cembranoids and guide the optimization of these compounds for potential therapeutic use. Full article

Soft robots demonstrate great potential for underwater exploration, particularly in tasks such as locomotion and biological sampling in fragile marine habitats. However, developing new forms of interaction with underwater life remains a challenge due to inadequate soft mechanisms for studying the behavior of marine invertebrates. We present a 7-cm in diameter anemone robot (“Soromone”) capable of performing biological sea anemones’ wiggling behavior under the water. Inspired by the body forms of adult cnidaria, we developed a morphing mechanism that serves as both structure and actuator for the Soromone’s behavior using a soft tectonics approach—a multistep, multiscale, heterogeneous soft material fabrication technique. As an actuator, the morphing mechanism can precisely control the Soromone via a fluid system; as a structure, it can reinstate the Soromone’s original shape by incorporating various degrees of stiffness or softness into a single piece of material during fabrication. Our study demonstrates the advantages of applying a Soromone under water, including increasing water flow for enhanced nutrient uptake, waste removal, and gas exchange. This cnidaria-inspired soft robot could potentially be adapted for interaction with coral reef ecosystems by providing a safe environment for diverse species. Future soft robotics design paradigms based on a soft tectonics approach could expand the variability and applicability of soft robots for underwater exploration and habitation. Full article

Analysis of NMR data reported for constituents found in the invasive soft coral Carijoa (Telesto) riisei has been used to develop a model that can identify punaglandins in C. riisei extracts. Principal component analysis of ¹H and ¹³C NMR data showed that the model can be used to identify the presence of various subclasses of punaglandins that possess different oxidations states of the cyclopentane ring. The application of this model through analysis of covariant HMBC data obtained from dichloromethane extracts showed that C. riisei has significant variability in punaglandin concentration, with many colonies being completely devoid of punaglandins. To verify the identity of compounds predicted by the model, purification of an extract obtained from C. riisei collected from an artificial reef in southeast Queensland led to the isolation of one new compound, 7Z-punaglandin 4-epoxide (1), a series of known punaglandins (2–6), and the known pregnanes 7–9. The absolute configurations of 7Z-punaglandin 4 epoxide (1), punaglandin 6 (4), and carijenone (6) were determined for the first time by comparison of experimental and TDDFT calculated ECD data. All the isolated punaglandins reported herein were predicted to be present using the NMR fingerprint model. Full article

This research explored the chemical composition of the soft coral Sarcophyton sp., leading to the discovery of six previously unreported cembranoids, sarcophynoids D–I (1–6), and three known analog compounds (7–9). Structural elucidation of the new metabolites was achieved by spectroscopic methods, including one- and two-dimensional (1D and 2D) NMR (COSY, HSQC and HMBC), high-resolution electrospray ionization mass spectrometry (HRESIMS), quantum mechanical NMR (QM-NMR) methods, electronic circular dichroism (ECD) calculations, and comparison with literature data. All isolated substances were screened for antibacterial activities, and most exhibited moderate inhibitory effects against six pathogenic bacterial strains, with MIC values between 8 and 64 μg/mL. In addition, the effects of these compounds on LPS and IFN-γ stimulated RAW264.7 cells, focused on the release of NO and TNF-α, were also evaluated, but were inactive at 20 μM. Full article

Inspired by the free swing of coral tentacles driven by water currents to actively repel microbial attachment, we have identified a unique physical anti-fouling strategy: coral “swinging effect” anti-fouling. Taking the fleshy soft coral (Sarcophyton trocheliophorum) as an example, its surface is covered with numerous soft tentacles. These coral tentacles utilize the force of water current fluctuations to freely sway, resembling a “feather duster” waving to repel microorganisms attempting to settle and establish themselves. Based on this characteristic, this study delves into the living habits of corals, observing the expansion and contraction cycles of their tentacles. Simultaneously, simulations of the anti-fouling performance of coral tentacles were conducted. It demonstrates that the “swinging effect” of the tentacles can effectively prevent the attachment of fouling organisms. Furthermore, this study uses S. trocheliophorum as a biomimetic prototype to design and prepare an artificial coral-mimic substrate (ACMS). It employs the common marine Gram-negative bacterium Paracoccus pantotrophus as a microbial sample to test anti-fouling performance in both pure static water environments and low-flow water environments. The results showed that the 13 mm-long ACMS could bend and overlap the surface of the rear tentacles to the greatest extent under the unidirectional scouring action of low-speed water flow (3.5 m/s), forming an anti-fouling protective layer. Additionally, the “swinging effect” phenomenon generated by the tentacles under water flow scouring demonstrated excellent anti-fouling effects. This study not only provides further evidence for research on coral antifouling performance but also offers new concepts and ideas for antifouling strategies in low-flow water environments, such as stationary ships in ports and underwater infrastructure facilities at docks. Full article

The 21st century has seen marine tourism in Southeast Asia transform in response to the rapid growth of SCUBA diving and snorkeling activities in the natural environment. However, despite this level of integration between recreation and the natural environment, few assessments have ever been conducted on the biodiversity or ecosystem values and experiences of the SCUBA diving community. Therefore, we explored the awareness, preferences and priorities of this community, with a particular emphasis on investigating the role of biodiversity documentation and species discoveries in motivating recreational diving. By conducting surveys of 366 recreational divers from Thailand, we were able to identify proportional priorities, finding greater valuation towards overall ecosystem esthetics than megafauna, with species-specific dive experiences being a niche but present interest. We also investigated diver priorities based on recently described or discovered marine fauna in Thai waters, focusing on five species of hard and soft coral, seven species of sea slug, and two species of shark. Of these, sea slug species were the most recognized and garnered the greatest potential economic value, likely due to their popularity with photographers. The results of this multidisciplinary investigation highlight the economic value of taxonomy and biodiversity research to the recreational SCUBA community. Full article

Cold-water soft corals are a known habitat for juvenile basket stars (Gorgonocephalus sp.), but the role of this relationship in the earliest life stages of basket stars warrants further investigation. Here, basket stars and colonies of the soft coral Gersemia rubiformis were collected together from the Funk Island Deep Marine Refuge (NW Atlantic) and maintained in a laboratory setting for observation. During this time, two developing (<1 mm disc diameter) basket stars were discovered on coral colonies and could be seen retracting with the coral polyp into the colony. The basket stars were recorded unharmed once the polyps were expanded again and continued to retract within the colony over the period of observation. The results of this study show that developing basket stars can spend time inside the coral colony, which could be a form of protection. Full article

A chemical investigation of the EtOAc fraction from soft coral Clavularia viridis resulted in the isolation of 12 undescribed dolabellane-type diterpenoids, namely clavirolides W–Z (1–4), clavularols A–H (5–12), and three known analogs (13–15). Their structures were characterized by an extensive analysis of spectroscopic data, including X-ray diffraction and ECD calculations for the assignment of absolute configurations. The structures of 2 and 4–6 are feathered as peroxyl-substituted derivatives, while compounds 7–12 possess additional oxidative cyclization, including epoxide or furan that are rare in the dolabellane family. All these compounds were evaluated for activities on cytotoxic and anti-inflammatory models. Compound 10 exhibited most potential against NO production in the BV2 cell induced by LPS with an IC₅₀ value of 18.3 μM. Full article

Atopic dermatitis (AD) is a common chronic skin disease affecting both children and adults. Currently lacking a clinical cure, AD presents significant physical and emotional challenges for patients and their families, substantially impacting their quality of life. This underscores significant unmet needs in AD management and highlights the necessity for developing effective therapeutic applications. Recently, several chlorine-containing active substances with promising pharmacological activity have been discovered in soft corals cultivated through coral farming. Among these, brianolide, isolated from the soft coral Briareum stechei, has shown promising potential. This study investigated brianolide’s regulatory effects on the inflammatory response in atopic dermatitis and its underlying mechanisms. Using an in vitro human keratinocyte cell line (HaCaT) stimulated with tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ) to mimic AD inflammation, brianolide was found to inhibit cytokine and chemokine expression via the mitogen-activated protein kinase (MAPK) and nuclear factor kappa-light-chain-enhancer of activated B cell (NFκB)-signaling pathways. In an in vivo animal model of 2,4-Dinitrochlorobenzene (DNCB)-induced AD, brianolide demonstrated anti-inflammatory effects, reducing transepidermal water loss (TEWL), ear thickness, erythema, and epidermal blood flow. These findings provide new insights into brianolide’s activity against AD-related inflammation, elucidate potential mechanisms, and contribute to understanding the pharmacological potential of natural coral products for AD treatment. Full article