Characterization of biotransformation, transmission and elimination processes in humans: Influence on the odorant and metabolite profiles of breath, urine and human milk

• Applicant: Professorin Dr. Andrea Büttner
• Subject Area: Food Chemistry ; Analytical Chemistry
• Term: from 2013 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 245860176

• Final Report Year: 2019

Final Report Abstract

With the approach developed in the present project three garlic-derived metabolites, namely AMS, AMSO and AMSO2, were identified and quantified in human milk and urine after the consumption of raw, cooked, and roasted garlic. Among these, only AMS is odor-active and thus contributes to the garlic-like odor of human milk related to maternal garlic intake. Furthermore, time resolved excretion as well as exhalation profiles of these metabolites have been monitored. Next to AMS, methanethiol could be monitored in breath as an additional metabolite. These results indicate that the volatile constituents of garlic are heavily metabolized in the body leading to metabolites that are eliminated via the breath, urine and milk. A gas chromatographic-olfactometric screening of cooked, roasted, and raw garlic revealed that the most important aroma-active compounds were detected with lower flavor dilution factors in heated garlic samples. Hence, the composition of the garlic substances is significantly changed due to heating. In view of these changes, differences in the metabolite composition and/or concentration of garlic-derived metabolites in human milk, urine and breath after consumption of cooked and roasted garlic were expected in comparison to raw garlic. Indeed, quantitative analyses confirmed that ingestion of processed garlic, especially cooked garlic, led to excretion of lower amounts of AMS, AMSO, and AMSO2 compared to the amounts detected after consumption of raw garlic. Interestingly, no further odorant transfer, e.g., related to the roasty odor quality of roasted garlic was determined in the milk and urine samples.

Publications

• Biotransformation, transmission and excretion processes of garlic odorants in humans: impact on human milk, urine and exhaled breath. Siegmund, Barbara (Ed.) et al. 15th Weurman Flavour Research Symposium. Book of Abstracts : 18-22 September 2017; Graz, Austria
  L. Scheffler, N. Sillner, Y. Sauermann, C. Sharapa, J. Beauchamp, A. Buettner
  
• Quantification of volatile metabolites derived from garlic (Allium sativum) in human urine, Frontiers in Nutrition 2019, 6, 43
  L. Scheffler, C. Sharapa, A. Buettner
  
• Quantification of volatile metabolites derived from garlic in human breast milk, Food Chemistry 2019, 274: 603-610
  L. Scheffler, C. Sharapa, A. Buettner