Metabolomics is an emerging field that entails the detailed characterization of the ensemble of metabolites produced by living organisms; subfields include drug metabolism and natural environmental toxin production. The first part of the dissertation pursued metabolism of glyceollins, i.e., isoflavones produced by soybeans, that are potential cancer therapy agents. In vivo glyceollin metabolites produced in rats were investigated by on-line Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry. An odd-electron fragment ion at m/z 148, formed in violation of the even-electron rule, and diagnostic of the glyceollin backbone, was discovered. Based on this finding, a negative mode precursor ion scanning method was developed to screen for glyceollins and their metabolites from biological samples. Products of both Phase I and Phase II metabolism were identified, none of which have been previously reported. Sulfated metabolites were confirmed by accurate mass measurement, while glucuronide conjugation was confirmed by enzyme-assisted glucuronidation by rat liver microsomes. Intact GSH-glyceollin conjugates were not observed, but breakdown products of the GSH pathway, i.e., cysteinylglyceine, cysteine, and acetylated cysteine, were identified as conjugates of oxygenated glyceollins. The identification of GSH by-product conjugates was confirmed in product ion spectra acquired in the negative mode (where peptide anions, and glyceollin-bearing cleaved peptide portions were observed), as well as in the positive mode (where intact oxygenated glyceollin fragments appeared without the initially-present peptide portion). Mass spectral evidence strongly supports a metabolic pathway involving initial epoxidation of glyceollins followed by GSH addition at the epoxidation site. The second part of the dissertation undertook the investigation of secondary metabolites called microbial volatile organic compounds (MVOCs) produced by fungi (mold) that have been reported to have adverse human health effects. MVOCs were collected onto different sorbent materials and analyzed by Thermal Desorption Analysis coupled with on-line Gas Chromatography-Mass Spectrometry. Fungal MVOCs were characterized from various simulated flooding conditions (brackish, freshwater, and saltwater) and different substrates (nutrient rich vs. low nutrient) to determine diagnostic MVOCs. Ten fungi from simulated environments were identified by genetic sequencing. Cladosporium sp. and Chaetomium sp. were cultivated and their emitted MVOCs, 3-furaldehyde and 3-(4-hydroxy-3-methoxyphenyl)-2-propenal, were proposed as diagnostic indicators of these fungi.

Damp building materials are subjected to degradation processes due to moisture and also microbial growth, with both of these giving rise to emissions of volatile organic compounds (VOCs) that may contribute to indoor air health problems. The overall aim of this thesis was to investigate emissions of reactive and non-reactive VOCs from damp building materials and from the microorganisms growing on them, and also to investigate the possible health impact of these compounds. Three studies were carried out in order to study emissions of VOCs. The first investigated emissions from a mixture of five fungi (Aspergillus versicolor, Fusarium culmorum, Penicillium chrysogenum, Ulocladium botrytis and Wallemia sebi) and the second emissions from the bacterium Streptomyces albidoflavus. In both studies the microorganisms were cultivated on three different building materials (pine wood, particle board and gypsum board) and one synthetic media, MEA and TGEA respectively. The bacterium was also cultivated on sand. Air samples from the cultures were collected on six different adsorbents and chemosorbents to sample a wide range of compounds such as VOCs, aldehydes, amines and light-weight organic acids. The samples were analyzed with gas chromatography, high-pressure liquid chromatography and ion chromatography. Mass spectrometry was used for identification of the compounds. Alcohols and ketones were the predominant compound groups identified. The bacterial culture growing on TGEA emitted ammonia, methylamine, diethylamine and ethylamine. The third study dealt with secondary emissions collected from buildings with moisture and mould problems. Samples were taken when the materials were dry and also after they had been wet for a week. Most alcohols and ketones could be identified from the wet materials. Trimethylamine and triethylamine, were identified from sand contaminated by Bacillus. One study looked at the development of a method for analysis of primary and secondary amines with LC-MS/MS. A three-step process was developed, with the first step screening the samples for NIT derivatives with selected reaction monitoring, SRM. In the second step a precursor ion scan gave the [M+H]+ ion, and the last step involved fragmentation with a product ion scan. It was possible to separate and identify all the investigated amines, which showed that the method was both specific and selective and therefore well suited for the analysis of amines in complex environments. The last study comprised two exposure studies. In study 1 each participant took part in two exposure conditions, one with air from mouldy building materials and one with blank air for a 60 minute period. In study 2 each participant was exposed four times (for a period of 10 min) at random to air from mouldy building materials and blank air, with and without nose-clip. The participants rated air quality and symptoms before, during and after each exposure. Exposure to moderate VOC levels resulted in reports of perceived poor air quality, but no such results were received when exposing the participants to low VOC levels.