LC-MS-based metabolomics for detecting adulteration in Tribulus terrestris-derived dietary supplements

The widespread usage of <i>Tribulus terrestris</i> dietary supplements has elicited concerns over product authenticity and possible adulteration. This research utilized an untargeted liquid chromatography-high resolution mass spectrometry (LC-HRMS) metabolomics methodology to assess the composition of <i>T. terrestris</i>-derived supplements. Authentic plant materials, simulated adulterated samples, and commercial products were analyzed using principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS-DA), and a convolutional neural network tool. The presence of PDE5 inhibitors and anabolic steroids in spiked samples was confirmed. Certain commercial products included undisclosed green tea and citrus-derived chemicals, likely incorporated to amplify stimulant effects and support testosterone-enhancing claims. Additionally, spirost-4-ene-3,12-dione was recognized as an indicator of possible steroidal saponin decomposition resulting from storage or processing conditions. This study illustrates the efficacy of LC-HRMS metabolomics in detecting supplement adulteration and emphasizes the need for rigorous quality control protocols to guarantee customer safety and product integrity.