Antibacterial and Cytotoxic Phenolic Polyketides from Two Marine-Derived Fungal Strains of Aspergillus unguis

A chemical investigation on the EtOAc extracts from two marine-derived fungal strains of Aspergillus unguis resulted in the isolation of three previously undescribed phenolic polyketides including unguidepside C (1), aspersidone B (3), and agonodepside C (12), and their 14 known congeners. The structures of the new compounds were determined based on detailed analysis and comparison of their spectroscopic data with literature values, as well as Snatzke’s method. The new compounds (1, 3, and 12) displayed a significant anti-Gram-positive bacterial activity, with MIC values ranging from 5.3 to 22.1 µM. Additionally, the isolated compounds (1–11 and 13–16) were evaluated for their cytotoxicity against a panel of tumor cell lines. Most of them (except for 9) displayed cytotoxicity against all the tested cell lines, with IC50 values ranging from 2.5 to 46.9 µM.

Polyketides and Meroterpenes from the Marine-Derived Fungi Aspergillus unguis 158SC-067 and A. flocculosus 01NT-1.1.5 and Their Cytotoxic and Antioxidant Activities

Ten secondary metabolites, including a new grifolin analog, grifolin B (1); a new homovalencic acid derivative, 12-hydroxyhomovalencic acid (7); and a compound isolated from a natural source for the first time (9), along with seven known compounds, grifolin (2), averantin (3), 7-chloroaverantin (4), 1′-O-methylaverantin (5), 7-hydroxy-2-(2-hydroxypropyl)-5-pentylchromone (6), homovalencic acid (8), and bekeleylactone E (10), were isolated from two fungal strains. The structures of 1–10 were identified by detailed analysis and comparison of their spectroscopic data with literature values. Compounds 9 and 10 showed moderate cytotoxic activity against a panel of cancer cell lines (PC-3, HCT-15, MDA-MB-231, ACHN, NCI-H23, NUGC-3), with the GI50 values ranging from 1.1 µM to 3.6 µM, whereas 1 displayed a weak 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity without cytotoxicity against all tested cell lines.

Natural Medicinal Compounds from Marine Fungi towards Drug Discovery: A Review

Marine fungi are species of fungi which live in estuaries environment and marine environment. These species are found in common habitat. Marine fungi are rich in antimicrobial compounds such as anthrones, cephalosporins, peptides, steroids. These compounds which are derived mainly focused in the area of anti-inflammatory, anti-oxidant, anti-fungal, anti-microbial, anti-fouling activity. Bioactive terpene compounds are produced by marine fungi and marine derived fungi can produce sclerotides, trichoderins. Marine fungi have become the richest sources of biologically active metabolites and structurally novel in the marine environment. In a recent study the marine derived fungi dichotomomyces cejpii exhibits activity towards cannabinoid which is used to treat alzheimer dementia. Aspergillus unguis showed significant acetyl cholinesterase besides its anti-oxidant activity. These acts as a promising intent for discovery of pharmaceutically important metabolites like alkaloids, peptides. Computational (in silico) strategies have been developed and broadly applied to pharmacology advancement and testing. This review summarizes the bioactive compounds derived from marine fungi in accordance with the sources and their biological activities.