Dihydroasparagusic acid: antioxidant and tyrosinase inhibitory activities and improved synthesis

J Agric Food Chem. 2013 Jul 17;61(28):6848-55. doi: 10.1021/jf401120h. Epub 2013 Jul 8.

Abstract

Dihydroasparagusic acid (DHAA) is the reduced form of asparagusic acid, a sulfur-containing flavor component produced by Asparagus plants. In this work, DHAA was synthetically produced by modifying some published protocols, and the synthesized molecule was tested in several in vitro assays (DPPH, ABTS, FRAP-ferrozine, BCB, deoxyribose assays) to evaluate its radical scavenging activity. Results show that DHAA is endowed with a significant in vitro antioxidant activity, comparable to that of Trolox. DHAA was also evaluated for its inhibitory activity toward tyrosinase, an enzyme involved, among others, in melanogenesis and in browning processes of plant-derived foods. DHAA was shown to exert an inhibitory effect on tyrosinase activity, and the inhibitor kinetics, analyzed by a Lineweaver-Burk plot, exhibited a competitive mechanism. Taken together, these results suggest that DHAA may be considered as a potentially active molecule for use in various fields of application, such as pharmaceutical, cosmetics, agronomic and food.

MeSH terms

  • Antioxidants / pharmacology*
  • Asparagus Plant / metabolism
  • Enzyme Inhibitors / pharmacology*
  • Free Radical Scavengers / pharmacology
  • Maillard Reaction
  • Monophenol Monooxygenase / antagonists & inhibitors*
  • Oxidation-Reduction
  • Thiophenes / chemical synthesis*
  • Thiophenes / chemistry
  • Thiophenes / pharmacology*

Substances

  • Antioxidants
  • Enzyme Inhibitors
  • Free Radical Scavengers
  • Thiophenes
  • dihydroasparagusic acid
  • 1,2-dithiolane-4-carboxylic acid
  • Monophenol Monooxygenase