Pyrenocine I, a new pyrenocine analog produced by Paecilomyces sp. FKI-3573

Persteroid, a new steroid from the marine-derived fungus Penicillium sp. ZYX-Z-143

A new steroid named persteroid (1) and seven known compounds (2-8) were isolated from the marine-derived fungus Penicillium sp. ZYX-Z-143. The structure of 1 was determined by HRESIMS, NMR, and ECD calculations. Compound 1 showed inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) with IC50 value of 46.31 ± 0.52 μM. Moreover, compound 1 potently suppressed nitric oxide (NO) production on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The cytotoxicity and antibacterial activity of all isolates were tested.

Chemical Constituents of the Deep-Sea-Derived Penicillium citreonigrum MCCC 3A00169 and Their Antiproliferative Effects

Six new citreoviridins (citreoviridins J-O, 1-6) and twenty-two known compounds (7-28) were isolated from the deep-sea-derived Penicillium citreonigrum MCCC 3A00169. The structures of the new compounds were determined by spectroscopic methods, including the HRESIMS, NMR, ECD calculations, and dimolybdenum tetraacetate-induced CD (ICD) experiments. Citreoviridins J-O (1-6) are diastereomers of 6,7-epoxycitreoviridin with different chiral centers at C-2-C-7. Pyrenocine A (7), terrein (14), and citreoviridin (20) significantly induced apoptosis for HeLa cells with IC₅₀ values of 5.4 μM, 11.3 μM, and 0.7 μM, respectively. To be specific, pyrenocine A could induce S phase arrest, while terrein and citreoviridin could obviously induce G0-G1 phase arrest. Citreoviridin could inhibit mTOR activity in HeLa cells.

An Updated Review of Secondary Metabolites from Marine Fungi

Marine fungi are valuable and richest sources of novel natural products for medicinal and pharmaceutical industries. Nutrient depletion, competition or any other type of metabolic stress which limits marine fungal growth promotes the formation and secretion of secondary metabolites. Generally secondary metabolites can be produced by many different metabolic pathways and include antibiotics, cytotoxic and cyto-stimulatory compounds. Marine fungi produce many different types of secondary metabolites that are of commercial importance. This review paper deals with around 187 novel compounds and 212 other known compounds with anticancer and antibacterial activities with a special focus on the period from 2011-2019. Furthermore, this review highlights the sources of organisms, chemical classes and biological activities (anticancer and antibacterial) of metabolites, that were isolated and structurally elucidated from marine fungi to throw a helping hand for novel drug development.

2-Oxaspiro[4.5]decane and α-pyrenocine derivatives from the endophytic fungus Roussoella sp. PSU-H51

One new 2-oxaspiro[4.5]decane, roussoellide, and one new α-pyrenocine, 2',3'-dihydropyrenocine A, together with nine known compounds including known arthropsolide A, and pyrenocines A and E, were obtained from the culture broth of the endophytic fungus Roussoella sp. Their structures were determined using spectroscopic data. The absolute configuration of known arthropsolide A was assigned on the basis of X-ray diffraction data using Cu Kα radiation. Known pyrenocine A displayed weak cytotoxic activity against breast cancer (MCF-7) cells with an IC₅₀ value of 27.1 µM and weak antifungal activity against Microsporum gypseum SH-MU-4 with an MIC value of 615.2 µM.

Microorganisms as a Potential Source of Molecules to Control Trypanosomatid Diseases

Trypanosomatids are the causative agents of leishmaniasis and trypanosomiasis, which affect about 20 million people in the world’s poorest countries, leading to 95,000 deaths per year. They are often associated with malnutrition, weak immune systems, low quality housing, and population migration. They are generally recognized as neglected tropical diseases. New drugs against these parasitic protozoa are urgently needed to counteract drug resistance, toxicity, and the high cost of commercially available drugs. Microbial bioprospecting for new molecules may play a crucial role in developing a new generation of antiparasitic drugs. This article reviews the current state of the available literature on chemically defined metabolites of microbial origin that have demonstrated antitrypanosomatid activity. In this review, bacterial and fungal metabolites are presented; they originate from a range of microorganisms, including cyanobacteria, heterotrophic bacteria, and filamentous fungi. We hope to provide a useful overview for future research to identify hits that may become the lead compounds needed to accelerate the discovery of new drugs against trypanosomatids.

Secondary Metabolites and Their Bioactivities Produced by Paecilomyces

Paecilomyces, a common saprobic filamentous fungus, not only plays an important role in biological control, but also has applications in medicine, food, and environmental protection. In this paper, 223 secondary metabolites and their bioactivities from 13 known species and various unidentified strains of Paecilomyces are reviewed. Their structures can be described as polyketide, terpenoid, peptide, alkaloid, quinone, pyrone, sterol, and fatty acid. They have been demonstrated varying biological activities, including antimicrobial, antitumor, insecticidal, antiplasmodial, antimalarial, nematicidal, herbicidal, and enzyme-inhibiting. This review provides a comprehensive overview of secondary metabolites and their biological activities from strains of Paecilomyces.

A Systematic Review on Secondary Metabolites of Paecilomyces Species: Chemical Diversity and Biological Activity

Fungi are well known for their ability to synthesize secondary metabolites, which have proven to be a rich resource for exploring lead compounds with medicinal and/or agricultural importance. The genera Aspergillus, Penicillium, and Talaromyces are the most widely studied fungal groups, from which a plethora of bioactive metabolites have been characterized. However, relatively little attention has been paid to the genus Paecilomyces, which has been reported to possess great potential for its application as a biocontrol agent. Meanwhile, a wide structural array of metabolites with attractive bioactivities has been reported from this genus. This review attempts to provide a comprehensive overview of Paecilomyces species, with emphasis on the chemical diversity and relevant biological activities of these metabolic products. Herein, a total of 148 compounds and 80 references are cited in this review, which is expected to be beneficial for the development of medicines and agrochemicals in the near future.

Two New Cytotoxic Compounds from a Deep-Sea Penicillum citreonigrum XT20-134

Penicillum citreonigrum XT20-134 (MCCC 3A00956) is a fungus with cytotoxic activity, derived from deep-sea sediment. Five new compounds, adeninylpyrenocine (1), 2-hydroxyl-3-pyrenocine-thio propanoic acid (2), ozazino-cyclo-(2,3-dihydroxyl-trp-tyr) (3), 5,5-dichloro-1-(3,5-dimethoxyphenyl)-1,4-dihydroxypentan-2-one (4), and 2,3,4-trihydroxybutyl cinnamate (5), together with 19 known compounds (6-24), were isolated from an ethyl acetate (EtOAc) extract of its fermentation. The structures of the new compounds were comprehensively characterized by high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS), 1D and 2D nuclear magnetic resonance (NMR). All isolates were evaluated for their cytotoxic activities. The heteroatom-containing new compounds 2 and 4 showed potent cytotoxicity to the human hepatoma tumor cell Bel7402 with IC₅₀ values of 7.63 ± 1.46, 13.14 ± 1.41 μM and the human fibrosarcoma tumor cell HT1080 with IC₅₀ values of 10.22 ± 1.32, 16.53 ± 1.67 μM, respectively.

A fruitful decade for fungal polyketides from 2007 to 2016: antimicrobial activity, chemotaxonomy and chemodiversity

The last three decades have shown that the fungi can be ‘biofactories’ of novel, bioactive secondary metabolites that produce numerous natural products with novel skeletons and biological activities. Particularly in the last 10 years, large numbers of antimicrobial fungal secondary metabolites have been discovered. This review provides an overview of key, defining developments of the last 10 years regarding the discovery of antimicrobial activity, chemotaxonomy and chemodiversity of fungal polyketides.

Phylogenetic and chemical diversity of fungal endophytes isolated from Silybum marianum (L) Gaertn. (milk thistle)

Use of the herb milk thistle (Silybum marianum) is widespread, and its chemistry has been studied for over 50 years. However, milk thistle endophytes have not been studied previously for their fungal and chemical diversity. We examined the fungal endophytes inhabiting this medicinal herb to determine: (1) species composition and phylogenetic diversity of fungal endophytes; (2) chemical diversity of secondary metabolites produced by these organisms; and (3) cytotoxicity of the pure compounds against the human prostate carcinoma (PC-3) cell line. Forty-one fungal isolates were identified from milk thistle comprising 25 operational taxonomic units based on BLAST search via GenBank using published authentic sequences from nuclear ribosomal internal transcribed spacer sequence data. Maximum likelihood analyses of partial 28S rRNA gene showed that these endophytes had phylogenetic affinities to four major classes of Ascomycota, the Dothideomycetes, Sordariomycetes, Eurotiomycetes, and Leotiomycetes. Chemical studies of solid-substrate fermentation cultures led to the isolation of four new natural products. In addition, 58 known secondary metabolites, representing diverse biosynthetic classes, were isolated and characterized using a suite of nuclear magnetic resonance and mass spectrometry techniques. Selected pure compounds were tested against the PC-3 cell line, where six compounds displayed cytotoxicity.

Panowamycins A and B, new antitrypanosomal isochromans produced by Streptomyces sp. K07-0010

Two new isochromans, panowamycins A and B, were purified by solvent extraction, silica gel and octadecylsilyl silica gel (ODS) column chromatography followed by preparative HPLC, from a culture broth of Streptomyces sp. K07-0010, together with the known compounds NFAT-133, conglobatin, piericidin C series and dinactin. Structures of panowamycins were elucidated as new analogs of NFAT-133 by spectroscopic studies including various NMR experiments. Panowamycins A and B showed moderate antitrypanosomal activity, with IC(50) values of 0.40 and 3.30 μg ml(-1), respectively.

Pyrenocines J-M: four new pyrenocines from the endophytic fungus, Phomopsis sp

Four new pyrenocines, named pyrenocines J-M (1-4), were isolated from an endophytic fungus, Phomopsis sp, by a bioassay-guided method. The structures of the new compound have been assigned from ¹H and ¹³C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. Preliminary studied showed that compounds 1, 2 and 4 showed good antifungal, antibacterial, and algicidal properties, while compound 3 had good antibacterial and algicidal properties.

In vitro antitrypanosomal activity of plant terpenes against Trypanosoma brucei

During the course of screening to discover antitrypanosomal compounds, 24 known plant terpenes (6 sesquiterpenes, 14 sesquiterpene lactones and 4 diterpenes) were evaluated for in vitro antitrypanosomal activity against Trypanosoma brucei brucei. Among them, 22 terpenes exhibited antitrypanosomal activity. In particular, α-eudesmol, hinesol, nardosinone and 4-peroxy-1,2,4,5-tetrahydro-α-santonin all exhibited selective and potent antitrypanosomal activities in vitro. Detailed here in an in vitro antitrypanosomal properties and cytotoxicities of the 24 terpenes compared with two therapeutic antitrypanosomal drugs (eflornithine and suramin). This finding represents the first report of promising trypanocidal activity of these terpenes. Present results also provide some valuable insight with regard to structure-activity relationships and the possible mode of action of the compounds.