Modulation of Free Amino Acid Profile in Healthy Humans Administered with Mastiha Terpenes. An Open-Label Trial

We aimed to explore whether plasma-free amino acids are modified in response to terpenes administration in healthy humans. In this open-label, single-arm acute trial, seventeen healthy male volunteers were administered with a naturally occurring product of known terpenes—namely mastiha—after overnight fasting. Blood samples were collected at different time points before and after ingestion. We aimed at identifying and quantifying 60 free amino acids in plasma applying Gas Chromatography-Mass Spectrometry. A total of 24 free amino acids were quantified. Branched-chain valine significantly decreased 4 h post-ingestion, whereas proline decreased at 6 h and ornithine at 2 h, compared to 0 h. These novel findings demonstrate that free amino acids levels are modulated in response to terpenes intake in healthy subjects.