Abstract
The metabolites entering the bloodstream and being excreted in urine as a result of consuming golden berries are currently unidentified. However, these metabolites potentially underlie the health benefits observed in various in vitro, animal, and human models. A nutritional intervention with 18 healthy human volunteers was performed, and urine was collected at baseline and after acute and short-term fruit consumption for 19 days. After UPLC-ESI/QToF-MS analysis, untargeted metabolomics was performed on the urine samples, and from the 50 most discriminant ions (VIP > 2) generated by a validated PLS-DA model (CV-ANOVA = 3.7e-35; R^2Y = 0.86, Q^2Y = 0.62 and no overfitting), 22 compounds were identified with relatively high confidence. The most discriminant metabolites confirmed by DHS/GC-MS2 analysis of volatiles in urine were sesquiterpenes (C15H22): 3 stereoisomers, β-vatirenene, β-vetivenene, and β-vetispirene, and 2 isomers, eremophila-1(10),8,11-triene and α-curcumene. Another major urinary biomarker was 4β-hydroxywithanolide E and its phase II derivatives, which were observed in urine for all individual up to 24 h after the fruit was consumed; thus, the bioavailability of this biomarker in humans was demonstrated for the first time. Additionally, the excretion of certain acylcarnitines and hypoxanthine in urine increased after golden berry consumption, which may be associated with a detoxifying effect and may occur because fats were utilized rather than carbohydrates to meet the body's energy needs. The main biomarkers of golden berry consumption are specific to this fruit, confirming its potential for the functional food market.