The Optimization of anti-tyrosinase activity in extraction of Persicaria pulchra (Bl.) Soják by using Response Surface Methodology (RSM)

Abstract

In these recent years, natural compound industry has been more and more attractive many interested. Although Persicaria pulchra (Bl.) Soják has been applied in Eastern medicine for long time, it has not researched deeply the chemical compounds and biological activities. In the experience, the presence of the polyphenol, flavonoid and alkaloid compounds with the value IC50 = 127,99 mg/mL proved that this plant owns potential anti-tyrosinase activity. To expand its using in the pharmaceutical and cosmetics industries, optimize the extraction conditions for tyrosinase inhibition from Persicaria pulchra (Bl.) Soják leaves using response surface methodology (RSM). The effect of the factors including ethanol concentration, temperature, solid/liquid ratio and extraction time on extraction of tyrosinase enzyme inhibitor from the Persicaria pulchra (Bl.) Soják leaves was investigated by experimental and Response Surface Methodology (RSM) methods. Results demonstrated that the mathematical modeling are compatible with experimental data and all four factors exhibit significant effect on tyrosinase inhibition activity of the extract (p<0,05). The optimal extraction conditions conjectured by the mathematical modeling as the content of solvent of 63% ethanol, the extraction temperature of 56.5 oC, the solid / liquid ratio 1: 8.18 g/mL, and the extraction time of 13.96 minutes. Under these conditions, the extract indicated that the best tyrosinase inhibition value of the extract for IC50 was 56,39 mg/mL, 2.5 times lower than the preliminary experiment value (127,99 mg/mL). Additionally, the experiment results of tyrosinase inhibition activity of optimal extraction showed that the results exported from mathematical modeling was equivalent with them.