## 4 Conclusions  
The combination of UVA and MVA results provided strong evidence to support the view that changes in the lipid composition of the growing media in _M. furfur_ CBS 1878 produce qualitative and semi-quantitative differences in their volatiles profiles. Additionally, the growth phase also affectsthe type and intensity of the released VOCs, despite the yeast growth not being equal in the tested media. In the UVA and MVA, several VOCs were differentiated as meaningful factors, including carbon dioxide, hexan-1-ol, pentyl acetate, isomer5 of methyldecane, dimethyl sulphide, undec-5-ene, isomer2 of methylundecane, isomer1 of methyldecane, and 2-methyletrahydrofuran. The differences observed using in vitro conditions in a controlled environment suggest how the presence of saturated (as PA) or unsaturated (as OA) fatty acids in the skin changes the VOCs profile in one species of the most important fungi genus from human skin microbiota. This species is particularly relevant because it is the only one known to be able to survive in PA, the most abundant saturated fatty acid in human sebum. Some VOCs are produced only when OA, PA, or a combination of both is present, but the complexity of the physiological and biochemical changes produced by the stressful nutritional conditions in these three restricted media should be studied further. The mDixon medium, with a more complex lipid composition, promotes the most diverse chemical profile, whereas the PA medium restricts the chemiodiversity and abundance of the VOCs produced. Our results demonstrate how variable are the volatile profiles of micro-organisms grown in different media. This study's findings are especially important for chemotaxonomic purposes or for studying the ecological function of scents. In the current research, the variation on media allowed us to describe VOCs not previously reported for _Malassezia_ or even for fungi. The ecological significance of our findings deserves future in vivo research to analyze the variability of lipid composition from skins of different humans, and how these variations induce changes in the volatiles profiles released by _M. furfur_. These modifications on human bouquets will determine many ecological interactions where VOCs play an important role, such as microbe-microbe, microbe-host, and microbe-insect interactions. Another important direction of research is the comparison of the VOCs profiles when _M. furfur_ behaves as a commensal versus pathogenic, with the aim of better understanding the virulence of this micro-organism or the beneficial effect and how it changes according to all of the dynamic complex transformations of the microbiota. The following are available online, Figure S1: Growth curves of _M. furfur_ in the mDixon, oleic acid (OA), palmitic acid (PA), and OA+PA medium and their confidence intervals of 99% using a loess method. Figure S2: Animation of rotational distribution of data in the PCA analysis of the volatiles profiles of _M. furfur_ growing in eight different experimental treatments. Table S1: Significant statistical univariate parameters found on 17 VOCs from _M. furfur_ and compounds highlighted by PCA and PLS-DA. Table S2: Chemical composition of mDixon medium. Table S3: Chemical composition of oleic acid (OA), palmitic acid (PA), and OA+PA media. The components of the minimal medium (MM) are listed in Materials and Methods. Methodology, M.G., M.G.-S., A.M.C. and C.C. ; Software, Formal Analysis, and Writing (Original Draft Preparation), M.G. ; Validation and Investigation, M.G. and A.M.C. ; Data Curation, A.M.C. and C.C. ; Writing (Review and Editing), all authors; Visualization, M.G. ; Conceptualization, Resources, Supervision, Project Administration, and Funding Acquisition, A.M.C., J.M. and C.C. This research was funded by the FAPA project of [PERSON] from the Faculty of Science at Universidad de los Andes, by the grants No.