A new sterol from the Vietnamese marine sponge Xestospongia testudinaria and its biological activities

Testusterol, a new sterol of the sponge species Xestospongia testudinaria from Phu Quoc island, Vietnam

A new sterol, named testusterol (1), and five known compounds (2-6) were isolated from the n-hexane and dichloromethane extracts of the sponge species Xestospongia testudinaria. Their chemical structures were elucidated based on extensive spectroscopic analyses (1D, 2D NMR, ESIMS and HRESIMS) and comparison with published data. The results of in vitro test (utilizing brine shrimp Artemia salina LEACH) showed that three extracts ethanol, dichloromethane, and ethanol/water, significantly inhibited Artemia salina with LC50 values ranging from 6.09 to 16.83 µg/mL. Remarkably, the new compound 1 exhibited potent inhibition against both Gram-positive (Staphyloccocus aureus, Bacillus subtilis, Lactobacillus fermentum), and Gram-negative (Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa) bacteria species, with IC50 values of less than 12.0 nM and MIC ranging from 4.70 to 75.23 nM as determined by the broth-microdilution assay.

Natural Products Derived from Marine Sponges with Antitumor Potential against Lung Cancer: A Systematic Review

Non-small-cell lung cancer (NSCLC), the most commonly diagnosed cancer and the leading cause of cancer-related death worldwide, has been extensively investigated in the last decade in terms of developing new therapeutic options that increase patient survival. In this context, marine animals are a source of new, interesting bioactive molecules that have been applied to the treatment of different types of cancer. Many efforts have been made to search for new therapeutic strategies to improve the prognosis of lung cancer patients, including new bioactive compounds and cytotoxic drugs from marine sponges. Their antitumoral effect can be explained by several cellular and molecular mechanisms, such as modulation of the cell cycle or induction of apoptosis. Thus, this systematic review aims to summarize the bioactive compounds derived from marine sponges and the mechanisms by which they show antitumor effects against lung cancer, exploring their limitations and the challenges associated with their discovery. The search process was performed in three databases (PubMed, SCOPUS, and Web of Science), yielding a total of 105 articles identified in the last 10 years, and after a screening process, 33 articles were included in this systematic review. The results showed that these natural sponge-derived compounds are a valuable source of inspiration for the development of new drugs. However, more research in this field is needed for the translation of these novel compounds to the clinic.

A New Sterol From the Polypore Fungus Ganoderma luteomarginatum and Its Cytotoxic Activities

A new sterol, ganolutol A (1), together with 4 known compounds 2 to 5, were isolated from the polypore fungus Ganoderma luteomarginatum collected in Myanmar. The chemical structures of the isolated compounds were determined based on extensive spectroscopic analyses in conjunction with comparisons with published data. Compounds 1 to 4 exhibited moderate cytotoxic activities against A549 (lung), MCF-7 (breast), and HeLa (cervical) human cancer cell lines, with IC50 values ranging from 10.1 to 86.6 μM.

Marine natural products

This review covers the literature published in 2019 for marine natural products (MNPs), with 719 citations (701 for the period January to December 2019) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1490 in 440 papers for 2019), together with the relevant biological activities, source organisms and country of origin. Pertinent reviews, biosynthetic studies, first syntheses, and syntheses that led to the revision of structures or stereochemistries, have been included. Methods used to study marine fungi and their chemical diversity have also been discussed.

Chemical Constituents of the Vietnamese Marine Sponge Gelliodes sp. and Their Cytotoxic Activities

A new decenoic acid derivative, gelliodesinic acid, and a naturally new alkaloid, together with three known furanoterpenoids and two known indole alkaloids, were isolated from the MeOH extract of the marine sponge Gelliodes sp. collected in Vietnam. The chemical structures of the isolated compounds were determined by analyses of 1D- and 2D-NMR and MS data and by comparisons of the data with those reported in the literature. The cytotoxicity assay against HeLa, MCF-7, and A549 cancer cell lines revealed that the three known furanoterpenes exhibited cytotoxic activities with IC₅₀ values ranging from 23.6 to 75.5 μM against the three cell lines, and that 1H-indole-3-carboxylic acid showed cytotoxicity with an IC₅₀ value of 89.2 μM against A549 cancer cell lines.

New cytotoxic polyacetylene alcohols from the Egyptian marine sponge Siphonochalina siphonella

Three new polyacetylenic alcohols, siphonellanols A-C (1-3), together with two known polyacetylenic alcohols (4-5), were isolated from the CHCl₃-soluble fraction of the methanolic extract of the marine sponge Siphonochalina siphonella, collected in Egypt. The structures of 1-3 were determined by spectroscopic analyses of their 1D-, 2D-NMR, and MS spectra and by comparisons with reported data. The cytotoxicity assay revealed that 1-3 exhibited moderate cytotoxic activities against a human cervical cancer cell line (HeLa), a human breast cancer cell line (MCF-7), and a human lung cancer cell line (A549) with IC₅₀ values ranging from 25.9 to 69.2 μM.

Microbial Sterolomics as a Chemical Biology Tool

Metabolomics has become a powerful tool in chemical biology. Profiling the human sterolome has resulted in the discovery of noncanonical sterols, including oxysterols and meiosis-activating sterols. They are important to immune responses and development, and have been reviewed extensively. The triterpenoid metabolite fusidic acid has developed clinical relevance, and many steroidal metabolites from microbial sources possess varying bioactivities. Beyond the prospect of pharmacognostical agents, the profiling of minor metabolites can provide insight into an organism's biosynthesis and phylogeny, as well as inform drug discovery about infectious diseases. This review aims to highlight recent discoveries from detailed sterolomic profiling in microorganisms and their phylogenic and pharmacological implications.