Catalytic role of serum albumin in decarboxylation of acetoacetate: A biochemical insight into the study by Yoshida et al.

This correspondence provides a biochemical commentary and supplementary hypothesis regarding the article by Yoshida et al. (2025) published in this journal on the relationship between blood acetone levels and gastric contents. While the original study demonstrated that blood acetone levels increase in the absence of food residue, we highlighted the catalytic role of human serum albumin (HSA) in the decarboxylation of acetoacetate (AcAc) to acetone, a non-redox process distinct from β-hydroxybutyrate formation. We hypothesized that under hypoglycaemic conditions (i.e., empty stomach), the lack of competition from glucose for HSA binding sites accelerates HSA-mediated conversion. This protein-catalytic perspective, supported by forensic data showing nearly complete conversion of AcAc to acetone, offers a more precise interpretation of ketone body profiles in forensic practice.