Optimization of a high‐resolution radical scavenging assay coupled on‐line to reversed‐phase liquid chromatography for antioxidant detection in complex natural extracts

Abstract

This paper reports the optimization of the on-line coupling of 2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid based radical scavenging assays with reversed-phase high-performance liquid chromatography. The residence time in the reactor was reduced to 6.4 s to ensure minimal peak broadening and loss of separation. Peak capacity losses between compound detection and measurement of the radical scavenging potential were reduced to 10% and lower on coupled column systems. The methodology was successfully applied for the detection of the scavenging activity of molecules encompassing a broad hydrophobicity range. The method shows promise for the assessment of low-molecular-weight polyphenols in red wine by coupled-column high-resolution high-performance liquid chromatography with mass spectrometry analysis.

Understanding the Effects of Roasting on Antioxidant Components of Coffee Brews by Coupling On‐line ABTS Assay to High Performance Size Exclusion Chromatography

“…Thus far, mainly reversed phase chromatography methods have been employed to detect individual compounds with antioxidant activity (e.g. De Smet et al , ). However, detection and quantification of individual CGAs with HPSEC was possible only to a limited extent due to much lower peak capacities in SEC.…”

Stabilization treatment of rice bran alters phenolic content and antioxidant activity

“…However at 734 nm, the extinction coefficient is ε 734 = 1.5 × 10 4 L mol −1 cm −1 whereas the extinction coefficient of 414 nm is ε 414 = 3.6 × 10 4 L mol −1 cm −1 (Koleva, Niederländer, & van Beek, 2001). Therefore, for online ABTS assay, detection was conducted at 414 nm rather than at 734 nm so that a larger absorption coefficient can be achieved because it reduces the risk of interfering absorption from sample components (De Smet et al, 2015). Coupled to the system were an external binary pump, coil column, and UV-Vis detector injecting ABTS solution at a flow rate of 0.38 ml/min.…”

Postcolumn determination of polyphenolic antioxidants in Cirsium vulgare (Savi) Ten. extracts

“…Such hyphenated techniques are able to separate, identify and quantify rapidly individual active compounds in complex plant‐derived materials without the need for the time‐consuming and skillful work related to traditional activity guided or bioassay guided fractionation. The majority of on‐line antioxidant assays are based on the 2,2‐diphenyl‐1‐picrylhydrazyl or 2,2`‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonate) synthetic radical decoloration reactions . However, the highest in vivo relevance possesses these on‐line antioxidant assays which employ luminol‐based chemiluminescence (CL) detection.…”

“…Disturbances in the oxidative state of cells are mostly caused by reactive oxygen species (ROS), which can cause direct damage to the DNA, protein and lipids. Therefore, oxidative stress is suspected to be involved in numerous human diseases, including cardiovascular diseases, certain types of cancers or assays are based on the 2,2-diphenyl-1-picrylhydrazyl or 2,2'azinobis-(3-ethylbenzothiazoline-6-sulfonate) synthetic radical decoloration reactions [5][6][7][8]. However, the highest in vivo relevance possesses these on-line antioxidant assays which employ luminol-based chemiluminescence (CL) detection.…”