Potentially harmful secondary metabolites produced by indoorChaetomiumspecies on artificially and naturally contaminated building materials

Abstract

The presence of the fungal genus Chaetomium and its secondary metabolites in indoor environments is suspected to have a negative impact on human health and well-being. About 200 metabolites have been currently described from Chaetomium spp., but only the bioactive compound group, chaetoglobosins, have been screened for and thus detected in buildings. In this study, we used a liquid chromatography high-resolution mass spectrometry approach to screen both artificially and naturally infected building materials for all the Chaetomium metabolites described in the literature. Pure agar cultures were also investigated to establish differences between metabolite production in vitro and on building materials as well as in comparison with non-indoor reference strains. On building materials, six different chaetoglobosins were detected in total concentrations of up to 950 mg/m from Chaetomium globosum along with three different chaetoviridins/chaetomugilins in concentrations up to 200 mg/m . Indoor Chaetomium spp. preferred wood-based materials over gypsum, both in terms of growth rate and metabolite production. Cochliodones were detected for the first time on all building materials infected by both C. globosum and Chaetomium elatum and are thus candidates as Chaetomium biomarkers. No sterigmatocystin was produced by Chaetomium spp. from indoor environment.

Diversity and taxonomy ofChaetomiumand chaetomium-like fungi from indoor environments

“…Chaetomium spp., together with several other genera such as Stachybotrys , Aspergillus and Penicillium , are of concern because of their ability to grow in the indoor environment and their association with production of bioactive metabolites (Brasel et al., 2005, Samson et al., 2010, Andersen et al., 2016, Došen et al., 2016). Depending on the type of water damaged building material, Chaetomium sensu lato are found in 16–66 % of environmental samples (Flannigan and Miller, 2011, Andersen et al., 2016).…”

“…All samples were further analysed for peaks not detected by the previous approach, and those were matched against Antibase2012 for a tentative identification. Metabolites that did not match were considered as novel compounds and their elemental composition was determined from the accurate mass (±2 ppm) and isotopic pattern (Kildgård et al., 2014, Došen et al., 2016). The peak areas of [M+H] + , [M+Na] + or [M+H 2 O] + of all the compounds, including the tentatively identified and the novel compounds, were then integrated in the Agilent MassHunter Quant software using extracted ion chromatograms ±12 ppm and the peak areas for multivariate data analysis.…”

Detection of Chaetomium globosum, Ch. cochliodes and Ch. rectangulare during the Diversity Tracking of Mycotoxin-Producing Chaetomium-like Isolates Obtained in Buildings in Finland

“…elatus (closely related to Ch. rectangulare); collectively, they represent 70% of the 145 isolates [2,3,9]. These studies showed that, although the members of the Ch.…”

Stachybotrys mycotoxins: from culture extracts to dust samples

“…Metabolite profiling of extracts of pure cultures, biomass and dust samples collected in the water-damaged kindergarten was performed using ultra-high performance liquid chromatography-diode array detection-quadrupole time-of-flight mass spectrometry (UHPLC-DAD-QTOFMS) as described by Dosen et al [ 39 ] using an Agilent Infinity 1290 UHPLC system (Agilent Technologies, Santa Clara, CA, USA) coupled to an Agilent 6545 QTOF MS equipped with a Dual Jet Stream electrospray ion source. The system was equipped with a diode array detector scanning in the range 200–640 nm 20 times/s [ 36 ].…”