Effect of Procedure Parameters on the Antioxidant Property of Perilla frutescens Leave Extracts

摘要

The aim of this study was to determine the procedure parameters, including drying, extracting and pH on the antioxidant activity and antioxidative compounds in Perilla frutescens leaves. The extraction of antioxidants from Perilla frutescens leaves is studied considering different drying and extracting procedures to investigate the selectivity of the process. The radical-scavenging activity (RSA) of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and the determination of the total phenolic content are applied to evaluate the antioxidant activity and antioxidative compounds of the Perilla frutescens leave extracts. The highest antioxidant activity is observed for the extract obtained by freeze drying, extracting by ultrasound with 80% methanol adjusted at pH 4. The antioxidant compound extraction yield was also the highest at these extraction conditions. The total phenol contents among the Perilla frutescens leave extracts produced by different drying procedures were similar, while the antioxidant activities were different This concluding that the amount of phenolic compounds extracted was similar but the type and probable structure of the phenolic changed during heat-drying procedure providing in this way. Our study showed that proper process technology could ultimately extract compounds potentially effective against diseases related to free radical oxidation.