**5. Conclusions**

The final aim of this work was to find a good approach to detect fungal biomarkers and to evaluate their detectability after exposure to simulated space and Mars-like conditions as well as to test instrumentation applicability for in situ analyses. Additionally, this work is useful to outline a database of biomarker of Earth microbial life, to improve the detection of biomarkers at Mars and to eliminate false-positives or negative detections [70]. In this context, we may consider melanin pigments as a fungal biomarker, owing to their high stability when detected in Martian regolith analogues after simulated space and Mars-like exposure. In addition, the detection of fatty acids through a GC-MS approach is of utmost importance since these molecules are found in the membranes of all living organisms and then, considered as potential biomarkers for life. Finally, although nucleic acids represent a controversial issue in the context of biomarkers, due to their lower stability and preservation over the time, our results demonstrate a good amplification and stability after the exposure to simulated space and Martian conditions. The results of this work are very appropriate given that the ExoMars Rosalind Franklin rover includes within its payload a Raman Laser Spectrometer and a Gas Chromatography–Mass Spectrometry instrument.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/article/10 .3390/jof7100859/s1, Figure S1: Raman signal coverage, Figure S2: Raman peak position.

**Author Contributions:** Conceptualization: J.-P.P.d.V., E.R. and S.O.; methodology, A.C., C.P., M.B., and L.B.; formal analysis, A.C., C.P., M.B. and L.B.; investigation, C.P., A.C., M.B., L.B., R.S. and U.B.; resources, S.O.; data curation, A.C., C.P., M.B. and L.B.; writing—original draft preparation, A.C. and C.P., writing—review and editing, A.C., C.P., M.B., L.B., R.S., U.B., E.R., J.-P.P.d.V. and S.O.; supervision, S.O.; funding acquisition, S.O. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was supported by the Italian Space Agency (BIOMEX MicroColonial Fungi-Experiment on ISS for tracking biomarkers on Martian and lunar rock analogues—ASI N.2013-063-R.0 and BioSigN MicroFossils—ASI N. 2018-6-U.0).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** The Italian National Program of Antarctic Researches (PNRA) and the Italian National Antarctic Museum "Felice Ippolito" (MNA) are also acknowledged for funding the collection of Antarctic samples CCFEE. Special acknowledgments also to Timm Roegler and its DLR-department Programmatics in Space Research and Technology and to the Ministry of Economics and Energy for supporting these studies within BIOMEX and BioSigN.

**Conflicts of Interest:** The authors declare no conflict of interest.
