Effect of solvent type and extraction conditions on extraction yield, total phenolic content and antioxidant activity of extract containing bioactive compounds from aerial part of marigold (Calendula officinalis L.)

In the present study, the extract containing bioactive compounds from marigold (Calendula officinalis L.) medicinal plant was extracted using water, ethanol, acetone, ethanol/water and acetone/water as solvent. Among the solvents studied, the ethanolic extract contained the highest total phenolic compounds. The effect of the solvent to raw material ratio (40:1-10:1 mL/g) and particle size (0.5-2.36 mm) on the quantitative and qualitative properties of ethanolic extract at ambient temperature (25°C) were investigated. Based on the results, the highest crude extraction yield and total phenolic compounds equal to 3.5 ± 0.17% and 36.94 ± 0.81 mg GAE/gram of sample was obtained using a ratio of 30:1 mL/g and a particle size of 1 mm at ambient temperature. At the concentration of 1 mg/ml, the antioxidant activity of the extract was 62.95 ± 2.68 % and 153.18 ± 1.20 μΜ Fe2+/L, respectively. The high correlation coefficient (R2>09594) between total phenolic compounds and antioxidant activity indicates the key role of phenolic compounds in antioxidant activity. Finally, the ethanolic extract obtained from C. officinalis under mentioned conditions can be introduced as a natural source of phenolic antioxidants for application in the food and nutraceutical industry as a natural preservative.