Ultrasound-Assisted Extractions for Improving the Recovery of Phenolics and Charantin from Bitter Melon and for Increasing the Antioxidant, Antidiabetic and Anti-Obesity Activities of Its Extracts

Abstract

Its bioactive - pound-rich probe- bath-type ultrasound-assisted (UAE) 60% ( v/v ) ethanol distilled The com position and bioactivity of the extracts prepared using compared with those obtained by conventional extraction methods, as autoclave extraction, ethanol extraction, and hot-water extraction. the yield of the autoclave extraction was the highest, the extracts obtained using UAE and aqueous ethanol a higher total phenolic content, antioxidant activity, antidiabetic activity ( α -amylase and α -glucosidase inhibitory activi- ties), and pancreatic lipase inhibitory activity than the conventional extracts. In particular, UAE with probe system and aqueous ethanol (UAE-P-E) extracting bioactive compounds, phenolics (total phenolic content of 18.73 mg GAE/g extract) and charantin (28.56 mg/g extract). Among all extracts, this prepared by UAE-P-E showed the highest DPPH radical scavenging activity (IC 50 of 0.55 mg/mL), ferric reducing antioxidant power (250.5 μmol TE/g extract), and pancreatic lipase inhibitory activity (76.38% at a concentration of 3.0 mg/mL). These results suggest that bioac - tive compound-rich extracts from bitter melon obtained using UAE, especially UAE-P-E, are expected to have high application potential as a functional food material, and are also expected to be used as natural antioxidant, antidiabetic, and anti-obesity agents.