Effect of acoustic cavitation phenomenon on bioactive compounds release from Eryngium caucasicum leaves

Abstract

This study investigated the effect of acoustic cavitation phenomenon generated by ultrasonic waves on bioactive compounds release from Eryngium caucasicum leaves into the surrounding medium. Peleg’s model was implemented to provide a clearer insight into the kinetics modeling during 60 min sonication at different temperatures (30–60 °C) and ultrasonic power (50–150 W). The experimental data were successfully fitted employing Peleg’s model with the high coefficient of determination (0.95), low root mean square error (0.003%) and mean relative percentage deviation modulus (6.40%). Then, the optimal conditions, using response surface methodology (RSM), were determined as ultrasonic power of 112.10 W, temperature of 50.00 °C and 33.53 min sonication time. Spectrophotometric analysis revealed that extract was a potential source of phenolics (64.00 ± 0.13 mg GAE g−1) with high scavenging ability of DPPH˙, ABTS˙+ and HO˙ (78.18 ± 0.12, 74.19 ± 0.14 and 49.38 ± 0.18%, respectively). The high-performance liquid chromatography (HPLC) revealed that gallic acid, chlorogenic acid, p-coumaric acid, ferulic acid, and apigenin were the main phenolics existed in the product. The process efficiency was enhanced significantly (p < 0.05) via performing preliminary static time (PST, 60 min). The quantity and quality of extracts improved using PST, where gallic acid had the highest concentration (24.59 ± 0.12 mg g−1). Scanning electron microscopy (SEM) images confirmed the dramatic effect of acoustic cavitation on cells structure.