Parrotia persica as a Potential Source of Bioactive Phenolic Compounds: Optimization of Extraction Parameters and Biological Activity Assay

Abstract

Parrotia persica is one of the endemic plants in Iran and belongs to the Hamamelidaceae family. A wide range of biological activities of this plant have been attributed to several phenolic compounds. In this study, the phenolic bioactive compounds extraction from P. persica leaves was performed using conventional and ultrasonic-assisted extraction (UAE) techniques through the response surface methodology (RSM) to optimize the best extraction conditions and reach the maximum amount of phenolic compounds. The central composite design (CCD) was conducted for the optimization of four extraction parameters, including extraction time, alcohol concentration, solvent-to-solid ratio, and temperature. The coding of parameters was performed as an independent variable at five levels. Quantitative and qualitative assessments were achieved by using HPLC, LC-MS, and UV-Vis spectrophotometry. According to the results, UAE was chosen as the best method with the optimal extraction values: 15 min as an extraction time, 40% alcohol portion in solvent, solvent-to-solid ratio equal to 30 : 1, and 25°C for temperature. In this regard, it was found that the similarity of experimental to predicted findings was 98.7% for the phenolic content and 94.9% for the mass extract in the UAE method. The findings showed a good similarity between the experimental and predicted values, and no significant changes were observed between the real and theoretical results. In addition, our finding revealed that the optimum extraction yield was 28.5% for the mass extract in the UAE optimization process. Furthermore, the antioxidant activity by DPPH assay indicates that the extract which was obtained using UAE in optimum condition, proposed remarkable antioxidant activity (IC50 29.86 μg·ml−1). Moreover, the cytotoxic assay was performed against PC-3 cancer cells, and it was found that the optimized extract using UAE has a promising cytotoxic activity (IC50 10.4 μg·ml−1) without toxicity toward normal cells. Since there is a possibility to use P. persica as one of the commercial herbal sources, the optimized extraction models could be utilized for scaling up the phenolic compound extraction from P. persica leaf.