Apolar Radical Initiated Conjugated Autoxidizable Triene (ApoCAT) Assay: Effects of Oxidant Locations on Antioxidant Capacities and Interactions.
Development of an antioxidant assay explaining antioxidant behaviors in complex food systems has been a challenging topic for food scientists. This research aimed to investigate antioxidant capacities and interactions of selected synthetic antioxidants and commercial natural antioxidant extracts using the CAT assay and a newly developed ApoCAT assay, which used water- and lipid-soluble azo radical initiators, respectively. Results suggested that the higher the hydrophobicity of an antioxidant, the higher the antioxidant capacity of an antioxidant observed in the ApoCAT assay. The relationship between the two different assays was explained by the ratio between the ApoCAT and the CAT values. Interestingly, all lipophilic derivatives of the antioxidants exhibited higher ApoCAT/CAT ratios than their hydrophilic derivatives. In the case of the commercial food-grade antioxidants, green tea extract and mixed tocopherols showed a higher antioxidant capacity in the ApoCAT assay than in the CAT assay, while grape seed and rosemary extracts did not show significantly different changes in behaviors in both assays. The study on antioxidant interactions revealed that additive, synergistic, and antagonistic effects between hydrophilic antioxidants and natural extracts, and mixed tocopherols could be observed in both the CAT and the ApoCAT assays, depending on the combined ratios. In most cases, at a particular ratio, the synergistic effect reached the maximum level before suddenly dropping to additive and antagonistic effects in both assays.
Food Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC) , 113 Thailand Science Park, Phaholyothin Road, Klong Luang, Pathumthani 12120, Thailand.
Atikorn
A
Panya
Food Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC) , 113 Thailand Science Park, Phaholyothin Road, Klong Luang, Pathumthani 12120, Thailand.|Food Technology Program, Mahidol University, Kanchanaburi Campus , Saiyok, Kanchanaburi 71150, Thailand.
Waranya
W
Temthawee
Department of Biotechnology, Faculty of Science, Mahidol University , Bangkok 10400, Thailand.
Natthaporn
N
Phonsatta
Food Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC) , 113 Thailand Science Park, Phaholyothin Road, Klong Luang, Pathumthani 12120, Thailand.
Danai
D
Charoensuk
Food Technology Program, Mahidol University, Kanchanaburi Campus , Saiyok, Kanchanaburi 71150, Thailand.
Pawinee
P
Deetae
Food Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC) , 113 Thailand Science Park, Phaholyothin Road, Klong Luang, Pathumthani 12120, Thailand.
Wonnop
W
Visessanguan
Department of Food Science, University of Massachusetts , Chenoweth Laboratory, 100 Holdsworth Way, Amherst, Massachusetts 01003, United States.|Bioactive Natural Products Research Group, Department of Biochemistry, Faculty of Science, King Abdulaziz University , P.O. Box 80203, Jeddah 21589, Saudi Arabia.
Eric A
EA
Decker
D000975:Antioxidants / Q000737:chemistry*; D028241:Camellia sinensis / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D027542:Rosmarinus / Q000737:chemistry*; D027843:Vitis / Q000737:chemistry*
D000975:Antioxidants; D016877:Oxidants; D010545:Peroxides; D010936:Plant Extracts; C049375:perhydroxyl radical
CAT assay; antioxidant capacity; lipid oxidation; modified CAT assay; natural antioxidant extracts