A research group led by Dr. Mayu Onozato and Prof. Takeshi Fukushima of the Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Toho University, made an innovative discovery utilizing the pre-column chiral derivatization reagent, CIMa-OSu, of which they have reported in 2021. Their study revealed, for the first time, the presence of D-amino acids, including D-alanine, D-serine, and D-aspartic acid, in black garlic foodstuffs. This technique is expected to be developed for future analysis of in vivoD-amino acid level alterations resulting from the intake of black garlic foodstuffs. The results of this research were published in the journal Molecules on February 13, 2023.
Previous studies have reported significant changes in various components (lipids, amino acids, organic acids, sulfur-containing compounds, and sugars, among others) during the transformation of raw garlic into black garlic via fermentation. However, there has been a lack of information regarding the presence of D-amino acids in black garlic. Therefore, the research group used their unique D,L-amino acid separation and quantification method to determine the content of D-amino acids in various garlic foodstuffs available on the market. While the only D-amino acid detected in fresh garlic foodstuffs (grated fresh garlic and freeze-dried garlic) was D-alanine, several D-amino acids were detected in black garlic foodstuffs, including D-serine and D-aspartic acid, in addition to D-alanine. These results suggest that several kinds of D-amino acids may be produced during the fermentation of garlic.
Molecules, February 13 issue
Determination of D– and L-amino acids in garlic foodstuffs by liquid chromatography-tandem mass spectrometry
Mayu Onozato, Haruna Nakanoue, Tatsuya Sakamoto, Maho Umino, Takeshi Fukushima