Evaluation of Antioxidant or Prooxidant Properties of Selected Amino Acids Using In Vitro Assays and in Oil-in-Water Emulsions Under Riboflavin Sensitization.
The antioxidant properties of selected amino acids were tested using in vitro assays and oil-in-water (O/W) emulsions under riboflavin (RF) photosensitization. Headspace oxygen content, lipid hydroperoxides, and conjugated dienes were determined for the degree of oxidation. Riboflavin photosensitization was adapted as the oxidation driving force. In vitro assays showed that cysteine had the highest antioxidant properties followed by tryptophan and tyrosine. However, in O/W emulsions under RF photosensitization, tyrosine inhibited lipid oxidation whereas tryptophan acted as a prooxidant. Tryptophan accelerated the rates of oxidation in O/W emulsion without RF. The antioxidant properties of amino acids differed depending on the antioxidant determination methods, oxidation driving forces, and food matrices.
Dept. of Food Science and Biotechnology, Sungkyunkwan Univ, Suwon, Republic of Korea.
HyeJung
H
Ka
Dept. of Food Science and Biotechnology, Sungkyunkwan Univ, Suwon, Republic of Korea.
BoRa
B
Yi
Dept. of Food and Nutrition, Kangwon Natl. Univ, Samcheok, Republic of Korea.
Mi-Ja
MJ
Kim
Dept. of Food Science and Biotechnology, Sungkyunkwan Univ, Suwon, Republic of Korea.
JaeHwan
J
Lee
D000596:Amino Acids / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology*; D003545:Cysteine / Q000494:pharmacology*; D004655:Emulsions / Q000737:chemistry; D015227:Lipid Peroxidation / Q000187:drug effects*; D008054:Lipid Peroxides / Q000378:metabolism; D016877:Oxidants / Q000494:pharmacology*; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species; D012256:Riboflavin / Q000737:chemistry*; D014364:Tryptophan / Q000494:pharmacology*; D014443:Tyrosine / Q000494:pharmacology*; D014867:Water / Q000737:chemistry
D000596:Amino Acids; D000975:Antioxidants; D004655:Emulsions; D008054:Lipid Peroxides; D016877:Oxidants; D017382:Reactive Oxygen Species; D014867:Water; D014443:Tyrosine; D014364:Tryptophan; D003545:Cysteine; D012256:Riboflavin
amino acid; antioxidant; in vitro assay; oil-in-water emulsion; oxidative stability