Optimization of polyphenol content determination in Perilla leaf by Response Surface Method

Abstract

In order to improve the utilization value of Perilla leaf polyphenol related food and food additives, and increase the edible added value of Perilla leaf, the polyphenol content of extracts from Perilla leaf was determined. The influence of Folin-Ciocalteu reagent dosage, sodium carbonate dosage, color developing temperature, color developing time and other factors on the determination of polyphenol content were investigated by single factor control variable method, and the determination conditions were optimized by response surface analysis. The experimental results showed that when the determination wavelength was 760 nm, the dosage of Folin-Ciocalteu reagent was 1.0 mL, the dosage of sodium carbonate reagent was 3.2 mL, the color development temperature was 30 °C, and the reaction time was 45 min, the optimal conditions for the determination of polyphenol content showed a good linear relationship with absorbance, and the regression equation was Y=0.0157X-0.0627, R2=0.9991. The stability, precision and reproducibility of the method met the requirements. The average recovery was 95.62% and the relative standard deviation (RSD) was 4.28%. The method was suitable for the determination of polyphenols in Perilla leaves, and the average content of polyphenols in Perilla leaves was 7.439 mg/g, RSD=4.34%. This study can provide data support for the development and researched of Perilla leaf polyphenols and food additives.