Profiling glucosinolate metabolites in human urine and plasma after broccoli consumption using non-targeted and targeted metabolomic analyses

• Published in: Food chemistry Vol. 309; p. 125660
• Main Authors: Sun, Jianghao, Charron, Craig S., Novotny, Janet A., Peng, Bing, Yu, Liangli, Chen, Pei
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 30.03.2020
• Subjects: Adult; Aged; Brassica - chemistry; Brassica - metabolism; Brassica oleracea; Broccoli; cysteine; Female; florets; Glucobrassicin; Glucoraphanin; Glucosinolate; Glucosinolates - blood; Glucosinolates - chemistry; Glucosinolates - metabolism; Glucosinolates - urine; High resolution mass spectrometry; hippuric acid; Human study; Humans; Imidoesters - chemistry; Imidoesters - metabolism; indoles; Indoles - chemistry; Limit of Detection; Male; Mass Spectrometry; metabolites; metabolomics; Metabolomics - methods; Metabolomics, Targeted analysis; Methoxyl glucobrassicin; Middle Aged; neoplasms; Oximes; physiological response; Principal Component Analysis; sulforaphane; Sulfoxides; urine; Broccoli; Glucosinolate; High resolution mass spectrometry; Metabolomics, Targeted analysis; Glucoraphanin; Human study; Glucobrassicin; Methoxyl glucobrassicin
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2019.125660

•Metabolomic analysis revealed changes in endogenous metabolites after broccoli consumption.•Metabolites from methoxyl-indole glucosinolates consumption are reported for the first time.•Targeted analysis HRAM-MS enabled detection of low concentrations of glucosinolate metabolites at nM level. Broccoli is a popular brassica vegetable and its consumption may decrease the occurrence of cancer in certain populations. To gain insight into the metabolites that may induce physiological responses to broccoli intake, a non-targeted metabolomic approach and a targeted approach for analysis of glucosinolate metabolites were developed using high resolution accurate mass spectrometry. A human study was conducted in which 6 subjects consumed a single meal of 200 g of uncooked broccoli florets. The metabolomic analysis revealed changes in endogenous metabolites and a decrease in hippuric acid after broccoli consumption. Targeted analysis using high-resolution, accurate mass-mass spectrometry (HRAM-MS) enabled detection of low concentrations (nM) of glucosinolate metabolites in human urine and plasma. Glucosinolate metabolites were found in human urine (13) and plasma (8), respectively. Metabolites from methoxyl-indole glucosinolates, arising from broccoli consumption, are reported for the first time. Most glucosinolate metabolites reached their peak concentration in urine 2–4 h after consumption while, in plasma, peak maxima were achieved 2 h after intake. The results suggest that glucoraphanin metabolites (sulforaphane, sulforaphane cysteine, sulforaphane N-acetyl cysteine) and indole metabolites (ascorbigen and methoxyl ascorbigen from indole glucosinolates) may serve as marker compounds for the intake of broccoli.