Pigmentosins from Gibellula sp. as antibiofilm agents and a new glycosylated asperfuran from Cordyceps javanica

Abstract

In the course of our exploration of the Thai invertebrate-pathogenic fungi for biologically active metabolites, pigmentosin A (1) and a new bis(naphtho-α-pyrone) derivative, pigmentosin B (2), were isolated from the spider-associated fungus Gibellula sp. Furthermore, a new glycosylated asperfuran 3, together with one new (6) and two known (4 and 5) cyclodepsipeptides, was isolated from Cordyceps javanica. The pigmentosins 1 and 2 showed to be active against biofilm formation of Staphylococcus aureus DSM1104. The lack of toxicity toward the studied microorganism and cell lines of pigmentosin B (2), as well as the antimicrobial effect of pigmentosin A (1), made them good candidates for further development for use in combination therapy of infections involving biofilm-forming S. aureus. The structure elucidation and determination of the absolute configuration were accomplished using a combination of spectroscopy, including 1D and 2D NMR, HRMS, Mosher ester analysis, and comparison of calculated/experimental ECD spectra. A chemotaxonomic investigation of the secondary metabolite profiles using analytical HPLC coupled with diode array detection and mass spectrometry (HPLC–DAD–MS) revealed that the production of pigmentosin B (2) was apparently specific for Gibellula sp., while the glycoasperfuran 3 was specific for C. javanica.

Phylogeny- and morphology-based recognition of new species in the spider-parasitic genus Gibellula (Hypocreales, Cordycipitaceae) from Thailand

“…This approach provides high-informative data to support morphological and molecular data for identifying fungal species, facilitates solving taxonomic problem as well as unraveling asexual morph-sexual morph links ( Frisvad et al 1990 ; Stadler et al 2003 ; Helaly et al 2018 ). As part of our ongoing research on taxonomy and secondary metabolite production of Thai invertebrate-pathogenic fungi, chemotaxonomy has been employed, resulting in the discovery of unprecedented secondary metabolites, including pigmentosin B from G. pigmentosinum and gibellamines from G. gamsii ( Helaly et al 2019 ; Kuephadungphan et al 2019 ). These compounds were found to be species-specific and could be designated as chemotaxonomic markers for the species.…”

Metabolites and Their Bioactivities from the Genus Cordyceps

“…Compound 38 also exhibited slight cytotoxicity to KB cells and its IC 50 value was 45 µM [ 38 ]. Beauverolide J b ( 39 ) was obtained from C. javanica [ 39 ]. A tripeptide, arginylphenylalanyl-methionine ( 40 ), isolated from C. gunnii , with the molecular formula of C 20 H 32 N 6 O 4 S, is a sedative and hypnotic active substance [ 40 ].…”

“…Compound 56 showed a slightly inhibiting effect on AChE, and its inhibition rate was 16.41% [ 48 ]. A new glycosylated asperfuran ( 58 ) was isolated from C. javanica , whose biological activity has not been reported [ 39 ]. A new stereoisomer of clonostachydiol, cordybislactone ( 59 ), and its hydrolyzed derivative ( 60 ), were obtained from Cordyceps sp.…”

Nonocarbolines A–E, β-Carboline Antibiotics Produced by the Rare Actinobacterium Nonomuraea sp. from Indonesia

“…According to our literature survey, 1,3-disubstituted β-carboline derivatives bearing a carbonyl moiety at C-1 and a carboxyl group at C-3 are known from plants, sponges, and fungi, while their amide-bearing analogues were reported from plants and bacteria. Of these, we show in Figure 3 stellarine A (6) from the marine-derived fungus Dichotomomyces cejpii F31-1 [26], cestrumine B (7) from the plant Cestrume hediundinum [27], and marinacarboline B (8) from the marine actinobacterium Marinactinospora thermotolerans [13].…”