Antioxidative Maillard Reaction Products Generated in Processed Aged Garlic Extract.

Area of Science:

• Food Chemistry
• Natural Product Chemistry
• Biochemistry

Background:

• Aged garlic extract (AGE) is known for its health benefits.
• Enhancing the antioxidant properties of AGE through processing can lead to more potent compounds.

Purpose of the Study:

• To investigate the effect of heat treatment on the antioxidant activity of aged garlic extract powder.
• To identify and characterize new antioxidant compounds formed during the heating process.

Main Methods:

• Aged garlic extract powder was heated at 100 °C for 24 hours.
• Antioxidant activity was assessed using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging (ARS) and oxygen radical absorbance capacity (ORAC) assays.
• Activity-guided fractionation, 1D/2D-NMR, CD spectroscopy, mass spectrometry, and LC-MS/MS were used for compound identification and pathway analysis.

Main Results:

• Heating significantly increased the antioxidant activity of the aged garlic extract.
• Twelve novel Maillard-type antioxidative compounds were isolated and characterized, alongside 14 known compounds.
• The identified antioxidants exhibited varying levels of ARS and ORAC activity, with ranges of 0.01–0.49 μmol TE/μmol and 0.01–3.50 μmol TE/μmol, respectively.
• Plausible formation pathways for new organic acid-type products were proposed and experimentally supported.

Conclusions:

• Thermal processing of aged garlic extract can generate novel compounds with enhanced antioxidant properties.
• The study identified new potential antioxidant agents derived from aged garlic, contributing to the understanding of Maillard reaction products in food chemistry.
• These findings suggest a method for developing more potent antioxidant formulations from garlic.