Interconvertible Pyridone Alkaloids from the Marine-Derived Fungus Penicillium oxalicum QDU1

Anti-inflammatory monomeric sorbicillinoids from the marine-fish-derived fungus Trichoderma sp. G13

Four new monomeric sorbicillinoids, trichillinoids A - D (1-4), along with two known dimeric sorbicillinoids (5 and 6), and five known monomeric sorbicillinoids (7-11), were obtained from the marine-fish-derived fungus Trichoderma sp. G13. They were structurally characterized on the basis of comprehensive spectroscopic investigations (NMR, HRESIMS, and ECD). Compounds 1-4 displayed moderate anti-inflammatory activities, according to inhibiting the production of NO in RAW264.7 cells activated with IC50 values ranging from 14 to 20 μM.

Novel Bioactive Natural Products from Marine-Derived Penicillium Fungi: A Review (2021-2023)

Marine-derived Penicillium fungi are productive sources of structurally unique and diverse bioactive secondary metabolites, representing a hot topic in natural product research. This review describes structural diversity, bioactivities and statistical research of 452 new natural products from marine-derived Penicillium fungi covering 2021 to 2023. Sediments are the main sources of marine-derived Penicillium fungi for producing nearly 56% new natural products. Polyketides, alkaloids, and terpenoids displayed diverse biological activities and are the major contributors to antibacterial activity, cytotoxicity, anti-inflammatory and enzyme inhibitory capacities. Polyketides had higher proportions of new bioactive compounds in new compounds than other chemical classes. The characteristics of studies in recent years are presented.

Structures, Biosynthesis, and Bioactivity of Oligomycins from the Marine-Derived Streptomyces sp. FXY-T5

Oligomycins are potent antifungal and antitumor agents. Mass spectrometry (MS)- and nuclear magnetic resonance (NMR)-based metabolomic fingerprinting analysis of marine-derived actinomycetes in our in-house library provided an oligomycin-producing strain, Streptomyces sp. FXY-T5. Chemical investigation led to the discovery of five new oligomycins, 24-lumooligomycin B (1), 4-lumooligomycin B (2), 6-lumooligomycin B (3), 40-homooligomycin B (4), and 15-hydroxy-oligomycin B (5), together with seven biosynthetically related known derivatives. Their structures were assigned by MS, NMR, electronic circular dichroism (ECD), and single-crystal X-ray diffraction analyses. The biosynthesis pathway of oligomycins was first proposed based on the analysis of a type I modular polyketide synthase (PKS) system and targeted gene disruption. As expected, the isolated oligomycins showed significant antiagricultural fungal pathogen activity and antiproliferative properties from which the possible structure-activity relationships were first suggested. More importantly, oligomycins induced significant G1-phase cell cycle arrest on cancer cells and significantly attenuated their Cyclin D1 and PCNA expression through a β-catenin signaling pathway.

A new anthraquinone derivative from the marine fish-derived fungus Alternaria sp. X112

A new anthraquinone, altermodinacid A (1), and five known derivatives, pachybasic acid (2), emodic acid (3), emodin (4), phomarin (5), and 1,7-dihydroxy-3-methylanthracene-9,10-dione (6), were discovered from a halotolerant fungus Alternaria sp. X112 isolated from a marine fish Gadus macrocephalus. Their structures were determined by analysing MS and NMR data. The cytotoxic effect, antiagricultural pathogens activity, antibacterial activity and quorum sensing inhibitory potential of new compound 1 were evaluated.

Astellolides R-W, Drimane-Type Sesquiterpenoids from an Aspergillus parasiticus Strain Associated with an Isopod

Sesquiterpenoids with a cage-like multiring frame are rarely found in nature. Mining of the isopod-derived fungus Aspergillus parasiticus SDU001 by the one strain-many compounds (OSMAC) strategy unexpectedly led to the discovery of fungal drimane-type sesquiterpenoids astellolide R (1), featuring an unusual cage-like 6/6/5/6/5 pentacyclic ring system, astellolide S (2), possessing a rare nicotinic acid building block, and astellolides T-W (3-6). Their structures were comprehensively assigned by spectroscopic data analysis, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Furthermore, compounds 3 and 5 exhibited anti-inflammatory activity by inhibiting the lipopolyssacharide-induced NO production in RAW264.7 macrophages with IC₅₀ values of 6.1 ± 0.8 and 6.8 ± 0.8 μM, respectively. A putative biosynthetic pathway for 1 is proposed. Our results enlarge the chemical space of the drimane-type sesquiterpenoids generated from endophytic fungi.