Xanthene and citrinin derivatives from the endophytic fungus Penicillium sp. T2-11

Multioxidized polyketides from an endophytic Penicillium sp. YUD17006 associated with Gastrodia elata

Three novel, highly oxygenated polyketides, multioketides A-C (1-3), and three previously described multioxidized aromatic polyketides (4-6), were isolated from an endophytic Penicillium sp. YUD17006 associated with Gastrodia elata. Their chemical structures were elucidated using extensive spectroscopic data, electronic circular dichroism calculations, and single X-ray diffraction analysis. All metabolites were characterized by a typical α,β-unsaturated ketone fragment and exhibited a high degree of oxidation. Multioketides A and B were identified as a pair of epimers featuring a rare dihydroisobenzofuranone core. Multioketide C possessed a novel 5/6/6/6 heterotetracyclic chemical architecture with unusual 1,4-dioxin functionalities. Plausible biosynthetic pathways for 1-6 were proposed. Additionally, compound 3 demonstrated weak inhibitory activities against both acetylcholinesterase and protein tyrosine phosphatase 1B.

Anti-Insect Properties of Penicillium Secondary Metabolites

In connection with their widespread occurrence in diverse environments and ecosystems, fungi in the genus Penicillium are commonly found in association with insects. In addition to some cases possibly implying a mutualistic relationship, this symbiotic interaction has mainly been investigated to verify the entomopathogenic potential in light of its possible exploitation in ecofriendly strategies for pest control. This perspective relies on the assumption that entomopathogenicity is often mediated by fungal products and that Penicillium species are renowned producers of bioactive secondary metabolites. Indeed, a remarkable number of new compounds have been identified and characterized from these fungi in past decades, the properties and possible applications of which in insect pest management are reviewed in this paper.

Bioactive sorbicillinoids from a rhizospheric soil-derived Paecilomyces sp. KMU21009

A new hybrid sorbicillinoid named paeciureallin (1) and a new monomeric sorbicillinoid named paecillyketide (2), along with six known analogues (3-8), were isolated from the rhizospheric soil-derived fungus Paecilomyces sp. KMU21009 associated with Delphinium yunnanense. Their structures were elucidated by extensive spectroscopic analysis and comparison with literature values. Paeciureallin (1) is the first example of hybrid sorbicillinoids possessing a rare sorbicillinoid urea unit and containing a β-D-ribofuranose functionality. In pharmacological studies, compounds 1 and 2 were evaluated for in vitro anti-inflammatory and cytotoxic activities. Paeciureallin (1) exhibited moderate cytotoxicity against SW480 and A549 cell lines, and the IC₅₀ values were 32.0 ± 0.1 and 34.4 ± 2.0 μM, respectively.