Celeiro Montero, MaríaVarela, EstherRodríguez, RocíoPenedo, ManuelLores Aguín, Marta2020-11-132020-11-132020Celeiro, M.; Varela, E.; Rodriguez, R.; Penedo, M.; Lores, M. Tracking Bacterial Spoilage in Cosmetics by a New Bioanalytical Approach: API-SPME-GC-MS to Monitor MVOCs. Cosmetics 2020, 7, 38http://hdl.handle.net/10347/23704The main goal of this work was the use of the powerful solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) technique to unequivocally identify microbial volatile organic compounds (MVOCs) derived from the enzymatic activity produced during metabolic processes using analytical profile index (API) biochemical tests. Three bacteria were selected for this study: Escherichia coli, Proteus mirabilis, and Pseudomonas aeruginosa. They were inoculated and incubated to both API components and real cosmetics, as well as to a mixture of them. Specific MVOCs were successfully identified as biomarkers for each one of the studied microorganisms: Indole and 2-nitrophenol as Escherichia coli markers, 2-undecanone and phenylethyl alcohol as Proteus mirabilis-specific markers, and 1-undecene and 2′-aminoacetophenone as Pseudomonas aeruginosa ones. In addition, a high number of MVOCs were identified as general markers of bacterial presence. The results revealed that the MVOCs’ formation is highly subtract dependent. Therefore, the ultimate and most challenging objective is to establish a relationship between the identified MVOCs and the original compound present in the substrate. This work establishes the design and development of this original approach, and its practical application to the control of microbial contamination in real cosmetic sampleseng© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)Atribución 4.0 Internacionalhttp://creativecommons.org/licenses/by/4.0/Microbial volatile organic compoundsBacterial contaminationConsumers’ healthAnalytical profile indexSolid-phase microextractionGas chromatography-mass spectrometryjournal article10.3390/cosmetics70200382079-9284open access