Optimization of the ultrasonic-assisted extraction process to obtain total phenolic and flavonoid compounds from watermelon (Citrullus lanatus) rind
Tan Phat Vo, Le Ngoc Huong Nguyen, Nguyen Phuc Thien Le, Thanh Phong, Dinh Quan Nguyen
Abstract
This context presents the study of ultrasonic-assisted extraction (UAE) to obtain phenolic and flavonoid compounds from watermelon rind powder (WRP). The antioxidant activity of the extracts was investigated using DPPH and ABTS+ assays. One-factor experiments were conducted to examine the effect of each factor (solid-to-liquid ratio (SLR), acetone concentration (AC), temperature, and time) on the UAE of WRP. Box-Behnken Design (BDD) model was employed to optimize the UAE conditions based on total phenolic contents (TPC), total flavonoid content (TFC), and their antioxidant activities. The optimal conditions were 1:30.50 SLR, 70.71% AC, 29.78 °C, and 10.65 min extraction time. There were no significant differences between predicted and experimental results (less than 6.0%), recommending a feasible and innovative process of deploying UAE to extract phenolics and flavonoids effectively from watermelon rind.