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Antioxidative Categorization of Twenty Amino Acids Based on Experimental Evaluation
Naijin Xu1, Guanqun Chen2, Hui Liu3
1College of Medical Laboratory, Dalian Medical University, Dalian 116044, China. naijinxu@aliyun.com.
Molecules (Basel, Switzerland)
|December 1, 2017
Summary
This study measured the antioxidant capacity of 20 amino acids using redox titration. Seven amino acids, including tryptophan and methionine, showed higher antioxidant potential than the others.
Area of Science:
- Biochemistry
- Analytical Chemistry
Background:
- Amino acids are vital protein building blocks.
- Their role as antioxidants in oxidation resistance is significant.
- Understanding their varying antioxidant capacities is crucial.
Purpose of the Study:
- To quantify the antioxidative capacity of 20 common amino acids.
- To compare the efficacy of micro-potassium permanganate and iodometric titration methods.
- To establish a reliable indicator for evaluating amino acid antioxidant potential.
Main Methods:
- Utilized micro-potassium permanganate titration.
- Employed iodometric titration.
- Quantitatively compared results from both methods for 20 amino acids.
Main Results:
- The product of experimental values from both titration methods proved a superior indicator of relative antioxidative capacity.
- Seven amino acids (tryptophan, methionine, histidine, lysine, cysteine, arginine, tyrosine) exhibited higher total antioxidative capacity.
- Results generally aligned with structural analysis of the amino acids.
Conclusions:
- Established a robust method for comparing amino acid antioxidant capacities.
- Identified specific amino acids with significant antioxidant potential.
- Provided insights into the relationship between amino acid structure and antioxidant activity.
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