Development of an Analytic Method for Sulfur Compounds in Aged Garlic Extract with the Use of a Postcolumn High Performance Liquid Chromatography Method with Sulfur-Specific Detection

Abstract

We developed a rapid postcolumn HPLC method for both qualitative and quantitative analyses of sulfur compounds, and this method helped elucidate a potential mechanism of cis-S1PC and SAMC action in AGE.

The Evidence for the Production Mechanism of cis-S-1-Propenylcysteine in Aged Garlic Extract Based on a Model Reaction Approach Using Its Isomers and Deuterated Solvents

“…Lawson et al showed the existence of cis-GS1PC in garlic, and its content was 0.28-0.55 µmol/g (fresh weight) [1,4]. We also confirmed the existence of cis-GS1PC in raw garlic and found that its content was 0.54 ± 0.12 µmol/g (dry-garlic) [3]. The qualitative analysis of cis-GS1PC in AGE was performed by LC-MS, and we obtained the following mass spectrum of cis-GS1PC: authentic cis-GS1PC: [M + H] + = m/z 291.1001, cis-GS1PC in AGE: [M + H] + = m/z 291.1002 (l " Fig.…”

“…Recently, we have reported that cis-S1PC is included in AGE [3]. The content of cis-GS1PC, a plausible precursor of cis-S1PC, in raw garlic was less than 50 % of cis-S1PC content in AGE on a molar basis [3,4]. These differences suggested that cis-S1PC was produced not only from the precursor, γ-glutamyl peptide, but also from the other compounds.…”

“…Over two decades, many scientists have come to pay more attention to S-alk(en)ylcysteines, such as S-methylcysteine, S-allylcysteine, and trans-S1PC, which are produced from γ-glutamyl-S-alk(en)ylcysteines [1,2]. Recently, we have reported that cis-S1PC is included in AGE [3]. The content of cis-GS1PC, a plausible precursor of cis-S1PC, in raw garlic was less than 50 % of cis-S1PC content in AGE on a molar basis [3,4].…”

“…These differences suggested that cis-S1PC was produced not only from the precursor, γ-glutamyl peptide, but also from the other compounds. Recently, we demonstrated that cis-S1PC was produced from trans-S1PC through the isomerization reaction [3]. However, the mechanism of isomerization reaction is unclear.…”

S-1-Propenylcysteine Improves TNF-α-Induced Vascular Endothelial Barrier Dysfunction by Suppressing the GEF-H1/RhoA/Rac Pathway

“…Brie y, raw garlic (Allium sativum L.) was sliced into pieces, which was followed by immersing in ethanol 20-50% (v/v) and aging for more than 10 months at room temperature. S1PC, SAC and SAMC were synthesized according to the previous methods [41,42], and the purity was >99.0%.…”