Volatile organic compounds (VOCs) in exhaled breath provide insights into various human metabolic processes and can be used to monitor physiological reaction to stimuli like exercise and medication. This lecture presents an integrated sampling protocol and analysis using proton transfer reaction-time-of-flight mass spectrometry (PTR-ToF-MS) for exhaled breath research. The approach was validated in situ on a participant cohort comprising of users of statins and non-statin users during a field campaign of three days of prolonged exercise, with no restrictions on food or drink consumption placed on participants.
A cluster of short-chain fatty acids produced in the gut as a result of carbohydrate fermentation, were identified in exhaled breath as indicators of gut microbiota activity due to prolonged exercise. They were also responsible for the primary differences in the breath profiles between non-statin and statin users.
The study provides novel information regarding the use of breathomics for monitoring non-invasively the changes of human metabolism and especially of the gut microbiome activity in relation to exercise and the use of medication, such as statins. In a broader context, this practical approach will become particularly useful for high-throughput screening, prior application of specific testing strategies requiring laboratory-support.