Polarography as a technique of choice for the evaluation of total antioxidant activity: The case study of selected Coprinus Comatus extracts and quinic acid, their antidiabetic ingredient

Abstract

This study was focused on in vitro screening of the total antioxidant activity of the selected extracts of the mushroom Coprinus comatus and quinic acid, one of their antidiabetic ingredients, by an uncommon electrochemical assay. Indeed, direct current (DC) polarographic HydroxoPerhydroxo Mercury(II) Complex (HPMC) assay based on decrease of anodic limiting current originating from HPMC formation in alkaline solutions of hydrogen peroxide at potential of mercury dissolution, observed upon gradual addition of antioxidants, was applied herein for the estimation of the natural products' antioxidativity. Quinic acid was found to exhibit most promising antioxidant potential (4.0 ± 0.2%µL⁻¹) being ≈ 2-fold more active than the screened C. comatus extract samples. Actually, such a finding puts some light on the antioxidativity of cyclic polyols, well understimated class of organic compounds, compared to aromatic (poly)phenolics. As a low cost, easy-to handle and accurate this polarographic assay may be thoroughly recommended for much broader use.

Keywords:

• cyclic polyols
• quinic acid
• antioxidativity
• polarography
• HPMC assay

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was kindly supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia [Research grants Nos. 172053, 172058, 173040, 43002, 43010 and 46001]. Author (Boris Pejin) dedicates this study to the memory of Diana, the late Princess of Wales.