A procedure to measure the antiradical efficiency of polyphenols

  • Sánchez-Moreno C
  • Larrauri J
  • Saura-Calixto F
  • 264

    Readers

    Mendeley users who have this article in their library.
  • 1.1k

    Citations

    Citations of this article.

Abstract

The kinetic behaviour of polyphenols common in fruits as free radical scavengers was studied using 2,2-diphenyl-1-picrylhydrazyl (DPPH.). After addition of different standard concentrations to DPPH. (0.025 g litre(-1)), the percentage of remaining DPPH. was determined at different times from the absorbances at 515 nm. The percentage remaining DPPH. against reaction time followed a multiplicative model equation: In [DPPHREM.] = b ln t + ln a. The slopes of these equations may be useful parameters to define the antioxidant capacity. The steeper the slope, the lower the amount of antioxidant necessary to decrease by 50% the initial DPPH. concentration (EC50). This parameter, EC50, is widely used to measure antioxidant power, but it does not takes into account the reaction time. Time needed to reach the steady state to the concentration corresponding at EC50 (T-EC50) was calculated, and antiradical efficiency (AE) was proposed as a new parameter to characterise the antioxidant compounds where AE = 1/EC50 T-EC50. It was shown that AE is more discriminatory than EC50. AE values are more useful because they also take into account the reaction time. The results have shown that the order of the AE (x10(-3)) in the compounds tested was: ascorbic acid (11.44)> caffeic acid (2.75) greater than or equal to gallic acid (2.62)> tannic acid (0.57)greater than or equal to DL-alpha-tocopherol (0.52) > rutin (0.21)greater than or equal to quercetin (0.19) > ferulic acid (0.12)greater than or equal to 3-tert-butyl-4-hydroxyanisole, BHA (0.10)> resveratrol (0.05). (C) 1998 SCI

Author-supplied keywords

  • Antiradical efficiency
  • DPPH
  • Free radical scavenging
  • Kinetic behaviour
  • Polyphenols

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Concepción Sánchez-Moreno

  • José A. Larrauri

  • Fulgencio Saura-Calixto

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free