<i>S</i>-Allyl-L-cysteine sulfoxide, a garlic odor precursor, suppresses elevation in blood ethanol concentration by accelerating ethanol metabolism and preventing ethanol absorption from gut

<p>Alcoholic beverages are enjoyed together with meals worldwide, but their excessive intake is associated with an increased risk of various diseases. We investigated whether <i>S</i>-allyl-L-cysteine sulfoxide (ACSO), a sulfuric odor precursor of garlic, suppresses elevation in plasma ethanol concentration by accelerating ethanol metabolism and preventing ethanol absorption from the gut in rats. ACSO and garlic extract with a high ACSO content (Garlic-H) suppressed elevation in concentrations of ethanol and acetaldehyde in plasma and promoted the activities of alcohol dehydrogenase and aldehyde dehydrogenase. However, ACSO and Garlic-H did not affect plasma acetate so much. Furthermore, we examined the change in plasma ethanol concentration by injecting ACSO or Garlic-H into the ligated stomach or jejunum together with ethanol solution. ACSO and Garlic-H suppressed the absorption of ethanol from the stomach and jejunum<b>,</b> but suppression in the jejunum was less than in the stomach. In conclusion, ACSO inhibits ethanol absorption and accelerates ethanol metabolism.</p> <p>A garlic odor precursor suppresses blood ethanol elevation.</p

A Simple Synthesis of Alliin and <i>allo</i>-Alliin: X‑ray Diffraction Analysis and Determination of Their Absolute Configurations

A simple method for the isolation of the bioactive compound alliin from garlic, as well as a method for the synthesis of diastereomerically pure alliin and <i>allo</i>-alliin on a preparative laboratory scale, was developed. The absolute configuration of the sulfur atom in alliin and <i>allo</i>-alliin was assigned on the basis of enzyme reactivity, optical rotatory dispersion, and circular dichroism analyses. A comparison of the results from these analyses, in combination with an X-ray diffraction study on a protected <i>allo</i>-alliin derivative, revealed <i>S</i> and <i>R</i> configurations of the sulfur atoms in alliin and <i>allo</i>-alliin, respectively. In addition, the same ¹H NMR spectrum was observed for synthetic and natural alliin. The absolute configuration of natural alliin was assigned for the first time on the basis of the NMR spectrum and X-ray coordinates