I did the experiment for the determination of reducing power by oyaizu 1986 method and found absorbance values but how to do the calculation to determine reducing power or the extract? do we have any formula? Or the absorbance values corresponds to reducing power? What unit should I use?
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https://www.google.com/url?sa=t&source=web&rct=j&url=https://innovareacademics.in/journal/ijpps/Vol3Suppl3/2155.pdf&ved=2ahUKEwjN1_Dgsc_1AhVM5uAKHSStADAQFnoECDcQAQ&usg=AOvVaw3crEBoFsZlEUWGXubuwEpo
The reducing power done by The method is based on the reduction of Fe3+ TPTZ complex (colorless complex) to Fe2+-tripyridyltriazine (blue colored complex) formed by the action of electron donating antioxidants at low pH. This reaction is monitored by measuring the change in absorbance at 593 nm. The Ferric reducing antioxidant power (FRAP) reagent was prepared by mixing 300 mM acetate buffer, 10 ml TPTZ in 40 mM HCl and 20 mM FeCl3.6H2O in the proportion of 10:1:1 at 37°. Freshly prepared working FRAP reagent was pipetted using 1-5 ml variable micropipette (3.995 ml) and mixed with 5 μl of the appropriately diluted plant sample and mixed thoroughly. An intense blue color complex was formed when ferric tripyridyl triazine (Fe3+ TPTZ) complex was reduced to ferrous (Fe2+) form and the absorbance at 593 nm was recorded against a reagent blank (3.995 ml FRAP reagent+5 μl distilled water) after 30 min incubation at 37°. All the determinations were performed in triplicates. The calibration curve was prepared by plotting the absorbance at 593 nm versus different concentrations of FeSO4. The concentrations of FeSO4 were in turn plotted against concentration of standard antioxidant trolox. The FRAP values were obtained by comparing the absorbance change in the test mixture with those obtained from increasing concentrations of Fe3+ and expressed as mg of Trolox equivalent per gram of sample.
The reducing power done by The method is based on the reduction of Fe3+ TPTZ complex (colorless complex) to Fe2+-tripyridyltriazine (blue colored complex) formed by the action of electron donating antioxidants at low pH. This reaction is monitored by measuring the change in absorbance at 593 nm. The Ferric reducing antioxidant power (FRAP)values were obtained by comparing the absorbance change in the test mixture with those obtained from increasing concentrations of Fe3+ and expressed as mg of Trolox equivalent per gram of sample.
les résultats du pouvoir reducteur sont présentés en termes d'absorbances (courbes d'absorbances en cas vous avez utilisé plusieurs concentrations). En cas tu as utilisé une seule concentration et vous avez utilisé une courbe standard par exemple l'acide ascorbique, vous exprimez les résultats sous forme d'equivalent acide ascorbique/mg d'extrait. Un autre parametre que on utilise c'est de calculer la concentration donnant une absorbance 0.5 que on symbolise (A0.5) en cas vous avez utilisé plusieurs concentrations. La valeur est calculée à partir de l equation de la courbe obtenue (Y=Ax+B); Y=0.5, A et B sont connus et vous calculez le x).
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