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Updated: Jul 3, 2026
A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes
Published on: June 10, 2022
Improved assay for determining the total radical-scavenging capacity of antioxidants and foods
Ki Won Lee1, Young Jun Kim, Nam Joo Kang
1Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea.
Abstract:
Free radicals play a crucial role in the pathophysiology of human diseases such as cancer, atherosclerosis, and neurodegenerative diseases, and considerable attention has been focused on functional foods (or nutraceuticals) that are able to decrease the concentrations of free radicals and consequently protect against these diseases. The present study investigated an improved quantitative assay to measure antioxidant activity using the stable and fast-reacting chromogenic indicator [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS). The ABTS-radical-scavenging activities of various antioxidants and apple extracts were measured in 96-well plates, and plots thereof were linearly interpolated, with the total radical-scavenging capacity quantified as the area under the curve. The first order of linear regression was obtained in a relationship between the absorbance reduction and various concentrations of the tested sample, and the total radical-scavenging capacity was expressed as the vitamin-C-equivalent antioxidant capacity. The advantages of this quantitative assay are that, first, it is fast, sensitive and confers little variation from experimental errors for single or mixed antioxidants; second, a large number of samples in a low quantity at a time can be run using 96-well plates.
Insights
This study presents a faster, more sensitive assay for measuring antioxidant activity using the ABTS method. The improved assay quantifies radical-scavenging capacity, aiding in the development of functional foods for disease prevention.
Area of Science:
- Biochemistry
- Food Science
- Analytical Chemistry
Background:
- Free radicals contribute to diseases like cancer and neurodegeneration.
- Functional foods and nutraceuticals are investigated for their ability to mitigate free radical damage.
- Accurate measurement of antioxidant activity is crucial for evaluating these protective compounds.
Purpose of the Study:
- To develop an improved, quantitative assay for measuring antioxidant activity.
- To utilize the [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS) radical-scavenging capacity assay for enhanced accuracy and speed.
- To quantify the total radical-scavenging capacity of antioxidants and apple extracts.
Main Methods:
- Employed the stable and fast-reacting chromogenic indicator [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS).
- Measured ABTS-radical-scavenging activities in 96-well plates for various antioxidants and apple extracts.
- Quantified total radical-scavenging capacity using linear regression and expressed it as vitamin-C-equivalent antioxidant capacity.
Main Results:
- Established a linear regression relationship between absorbance reduction and sample concentration.
- Successfully quantified the total radical-scavenging capacity as the area under the curve.
- Demonstrated the assay's speed, sensitivity, and low experimental error for diverse antioxidant samples.
Conclusions:
- The developed ABTS assay offers a fast, sensitive, and reliable method for quantifying antioxidant capacity.
- The assay's efficiency in handling multiple samples in 96-well plates facilitates high-throughput screening.
- This improved method supports the evaluation of functional foods and nutraceuticals for disease prevention strategies.
