Due to the complex nature of the plant extracts, little is known about the mechanism of interactions responsible for the synergistic antioxidant activity, which are very sensitive and depend on factors such as polarity, the different compounds in the formulation (or extract), and also on their present concentration.
Thus, besides the analytical-methods approaches (HPLC to defined in the major compounds and your concentrations in the standardized herbal preparations) are needed for the different evaluation of the antioxidant activity (DPPH, ORAC, FRAP, MCA...), to analyze the relative contribution of the formulation (or compounds) to the antioxidant synergy, given that the same formulation may show synergistic behavior at one concentration ratio, while antagonistic behavior at the other (Prieto’s model, e.g.).
Article Antioxidant synergistic effects of Osmanthus fragrans flower...
Synergism in antioxidant activity can be discussed as: Synergistic interactions between the antioxidant components from various natural products; synergism between antioxidant components in different solvent fractions of same plant extract or mixture of different herbal preparations; and synergism between synthetic .
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