Unique Polyhalogenated Peptides from the Marine Sponge Ircinia sp

Neuroprotective and nephroprotective effects of Ircinia sponge in polycyclic aromatic hydrocarbons (PAHs) induced toxicity in animal model: a pharmacological and computational approach

The present study investigated the neuroprotective and nephroprotective effects of the sponge Ircinia sp. ethyl acetate extract (ISPE) against persistent aromatic pollutants in vitro and in vivo. Different exponential experimental assays were applied to this study. An in vitro study to investigate the potential therapeutic effect of ISPE using antioxidants (for example, ABTS and DPPH) and anti-Alzheimer assays (inhibition of acetylcholinesterase); the in-vivo study was designed to evaluate the protective effect of ISPE as neuroprotective and nephroprotective against the destructive effect of PAH. Several assays included oxidative assays (LPO), antioxidant biomarkers (GSH, GST), and inflammatory and neurodegenerative biomarkers (PTK,SAA). Additionally, the results were confirmed using histopathological examination. The in silico screening study improved the in vitro and in vivo findings through interaction between the aryl hydrocarbon receptor (AHR) and the polyphenolic content of ISPE extract, which was determined using LCMSM. The results and discussion showed that ISPE exhibited a promising antioxidant and anti-acetylcholinesterase activity as evidenced by IC₅₀ values of 49.74, 28.25, and 0.18 µg/mL in DPPH, ABTS, and acetylcholinesterase inhibition assays, respectively. In vivo, the study showed that animals receiving ISPE before poly aromatic hydrocarbons administration PAHs (Prot, ISPE) showed significant amelioration in kidney functions manifested by the reduction of serum urea, uric acid, and creatinine by 40.6%, 66.4%, and 134.8%, respectively, concerning PAH-injected mice (HAA). Prot, ISPE revealed a decline in malondialdehyde (MDA) and total proteins (TP) in kidney and brain tissues by 73.63% and 50.21%, respectively, for MDA and 59.82% and 80.41%, respectively, for TP with respect to HAA. Prot, ISPE showed significant elevation in reduced glutathione (GSH) and glutathione transferase (GST) in kidney and brain tissues and reduction in the inflammatory and pre-cancerous biomarkers, namely, serum protein tyrosine kinases (PTKs) and serum amyloid A (SAA). These findings were further supported by histopathological examination of kidney and brain tissues, which revealed normal structure approaching normal control. Metabolic profiling of ISPE using LC-MS-MS showed the presence of fourteen polyphenolic compounds belonging mainly to phenolic acids and flavonoids. In silico study revealed that all the tested compounds exerted certain binding with the aryl hydrocarbon receptor, where rutin showed the best fitting (ΔG =  - 7.6 kcal/mol^-1) with considerable pharmacokinetic and pharmacodynamic properties revealed from in silico ADME (Absorption, Distribution, Metabolism, and Excretion) study. Hence, it can be concluded that the Ircinia sponge showed a promising protective effect versus kidney and brain toxicity triggered by PAHs.

A concise review on marine bromopyrrole alkaloids as anticancer agents

Natural products have been the most important sources of chemically diverse raw materials that have inspired pharmaceutical discoveries over the past few decades. Many pharmaceutical companies are utilizing plant extracts to develop relatively crude therapeutic formulations. The interesting chemicals identified as natural products are derived from the phenomenon of biodiversity, where the interactions between the organisms and their environment formulate the diverse and complex chemical entities within them that enhance their survival and competitiveness. Marine sponges are rich sources of natural products and have provided an infinite supply of bioactive metabolites. Bromopyrrole alkaloids are a good example of marine metabolites, have a broad range of biological activity, and represent a fascinating example of chemical diversity of secondary metabolites elaborated by marine invertebrates. The isolation and synthesis of this structural class have been investigated, resulting in a series of bromopyrrole alkaloids with potential lead hits. This review presents the detailed isolation and anticancer activity of marine bromopyrrole alkaloids, and will be of interest to the wider research community both in academic and industrial settings.

Absolute Stereochemistry Determination of Bioactive Marine-Derived Cyclopeptides by Liquid Chromatography Methods: An Update Review (2018-2022)

Cyclopeptides are considered as one of the most important classes of compounds derived from marine sources, due to their structural diversity and a myriad of their biological and pharmacological activities. Since marine-derived cyclopeptides consist of different amino acids, many of which are non-proteinogenic, they possess various stereogenic centers. In this respect, the structure elucidation of new molecular scaffolds obtained from natural sources, including marine-derived cyclopeptides, can become a very challenging task. The determination of the absolute configurations of the amino acid residues is accomplished, in most cases, by performing acidic hydrolysis, followed by analyses by liquid chromatography (LC). In a continuation with the authors' previous publication, and to analyze the current trends, the present review covers recently published works (from January 2018 to November 2022) regarding new cyclopeptides from marine organisms, with a special focus on their biological/pharmacological activities and the absolute stereochemical assignment of the amino acid residues. Ninety-one unreported marine-derived cyclopeptides were identified during this period, most of which displayed anticancer or antimicrobial activities. Marfey's method, which involves LC, was found to be the most frequently used for this purpose.

Naturally Occurring Organohalogen Compounds-A Comprehensive Review

The present volume is the third in a trilogy that documents naturally occurring organohalogen compounds, bringing the total number-from fewer than 25 in 1968-to approximately 8000 compounds to date. Nearly all of these natural products contain chlorine or bromine, with a few containing iodine and, fewer still, fluorine. Produced by ubiquitous marine (algae, sponges, corals, bryozoa, nudibranchs, fungi, bacteria) and terrestrial organisms (plants, fungi, bacteria, insects, higher animals) and universal abiotic processes (volcanos, forest fires, geothermal events), organohalogens pervade the global ecosystem. Newly identified extraterrestrial sources are also documented. In addition to chemical structures, biological activity, biohalogenation, biodegradation, natural function, and future outlook are presented.

Marine natural products

Covering: 2020This review covers the literature published in 2020 for marine natural products (MNPs), with 757 citations (747 for the period January to December 2020) 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 (1407 in 420 papers for 2020), 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. A meta analysis of bioactivity data relating to new MNPs reported over the last five years is also presented.

Antibacterial and Cytotoxic Potential of Two Steroids from the Indonesian Soft Coral Sinularia polydactila

Background: Soft corals of the genus Sinularia are well recognized as a rich source of steroidal compounds. These constituents have been reported as possessing antitumor, antimicrobial, and antiviral activities. Objectives: This study was designed to isolate and elucidate antibacterial and cytotoxic compounds from the soft coral Sinularia polydactila. Methods: Structure elucidation of steroids was determined based on spectroscopic data through 1D and 2D NMR analyses and mass spectrometry, with the results compared to data in the literature. Antibacterial activity was determined using four human bacterial pathogens, namely B. subtilis (ATCC 6633), P. aeruginosa (ATCC 27853), S. aureus (ATCC 25923), and E. coli (ATCC 25922). Cytotoxic activity was evaluated using the human colon cancer cell HCT 116 and brine shrimp lethality assay (BSLA). Results: Two steroids (Compounds 1 - 2) were isolated from the Indonesian soft coral Sinularia polydactila. (22R,23R,24R)-22,23-methylene-24-methylcholest-6-en-5α,8α-epidioxy-3β-ol (1) and 5α,8α-Epidioxy-24(R)-methylcholesta-6,22-dien-3α-ol (2) showed moderate activity against colon carcinoma cancer HCT 116 at the concentrations of 24.8 and 27.3 μg/mL, respectively. Furthermore, compounds 1 and 2 showed cytotoxic activity using the brine shrimp lethality assay with the concentrations of 57.1 and 121.3 3 μg/mL, respectively. Compound 2 showed moderate activity against S. aureus and B. subtilis at the 250 μg/mL concentration. Conclusions: Two steroids isolated from soft coral Sinularia polydactila were found to possess moderate cytotoxic and antibacterial activities.

Marine Pyrrole Alkaloids

Nitrogen heterocycles are essential parts of the chemical machinery of life and often reveal intriguing structures. They are not only widespread in terrestrial habitats but can also frequently be found as natural products in the marine environment. This review highlights the important class of marine pyrrole alkaloids, well-known for their diverse biological activities. A broad overview of the marine pyrrole alkaloids with a focus on their isolation, biological activities, chemical synthesis, and derivatization covering the decade from 2010 to 2020 is provided. With relevant structural subclasses categorized, this review shall provide a clear and timely synopsis of this area.

Chemical Diversity and Biological Activity of Secondary Metabolites Isolated from Indonesian Marine Invertebrates

Marine invertebrates have been reported to be an excellent resource of many novel bioactive compounds. Studies reported that Indonesia has remarkable yet underexplored marine natural products, with a high chemical diversity and a broad spectrum of biological activities. This review discusses recent updates on the exploration of marine natural products from Indonesian marine invertebrates (i.e., sponges, tunicates, and soft corals) throughout 2007-2020. This paper summarizes the structural diversity and biological function of the bioactive compounds isolated from Indonesian marine invertebrates as antimicrobial, antifungal, anticancer, and antiviral, while also presenting the opportunity for further investigation of novel compounds derived from Indonesian marine invertebrates.