Novel Spirocyclic Trichothecanes, Spirotenuipesine A and B, Isolated from Entomopathogenic Fungus, Paecilomyces tenuipes

Abstract

Entomopathogenic fungi forming fruiting bodies have been employed as tonics and antitussives from ancient times. Paecilomyces tenuipes, which is also called Isaria japonica, is a very popular entomopathogenic fungus and is often considered a health food in northeast Asian countries such as China, Korea, and Japan. We cultivated the fruiting bodies of Paecilomyces tenuipes. Among the large-scale cultivations, fruiting body grown in barley grain contained two novel spirocyclic trichothecane derivatives, spirotenuipesine A (1) and B (2), and known trichothecane mycotoxins. Compounds 1 and 2 showed potent activity in neurotrophic factor biosynthesis in glial cells. The isolation of these compounds indicated that P. tenuipes is a promising source for producing various biologically active substances including trichothecanes. It is noteworthy that trichothecane mycotoxins are present in Paecilomyces tenuipes, which is typically used in medicinal health food.

Metabolic Conservation and Diversification of Metarhizium Species Correlate with Fungal Host-Specificity

“…Interestingly, these metabolites were originally identified from other insect pathogenic fungi except the Streptomyces -origin of polyketones naphthgeranines (Wessels et al, 1991). For example, torrubiellutins were identified from the insect pathogen T. luteorostrata (Pittayakhajonwut et al, 2009), hirsutellones from Hirsutella nivea (Isaka et al, 2005), and trichothecanes tenuipesine (Kikuchi et al, 2004a), spirotenuipesines (Kikuchi et al, 2004b), and paecilomycines (Kikuchi et al, 2004c) from the insect pathogen Paecilomyces tenuipes (now re-classified as Isaria tenuipes ). The identification of similarly conserved SM gene clusters among the Metarhizium and Torrubiella species ( Figure 1C ) supports, at least in part, the production of same metabolites by different fungal species that has been frequently observed (Gibson et al, 2014).…”

Antifungal Polyketides and Other Compounds from Amazonian Endophytic Talaromyces Fungi

“…Cordyanhydrides (7 and 8) were originally described from the insect pathogen fungus Cordyceps pseudomilitaris, 24 and more recently from Paecilomyces tenuipes, 29 and Dwayaangam colodena. 30 So far, compounds bearing maleic anhydride moieties such as telfairic and itaconitin anhydrides, in addition to regular cordyanhydrides are known as insecticidal compounds. 24 To the best of our knowledge a natural methyl ester from any of these compounds was not previously described.…”

Beauvericin production by the Lepidoptera pathogenic fungus Isaria tenuipes: Analysis of natural specimens, synnemata from cultivation, and mycelia from liquid-media fermentation

“…silkworm) or solid media are used for commercial products. As for low molecular weight metabolites from this fungus, a group of trichothecanes, paecilomycine A, 18 tenuipesines A and B, 19 and spirotenuipesines A-C, 20 have been isolated from the synnemata grown on silkworms, wherebeauvericin *To whom correspondence should be addressed. E-mail: isaka@biotec.or.th as a pseudodipeptide, hanasanagin (3,4-diguanidino-butanoyl-DOPA) was isolated by other group.…”