Optimization of ultrasound-assisted extraction of phenolic compounds from bitter melon (Momordica charantia) using response surface methodology

Abstract

Bitter melon is rich in phenolic compounds and has significant potential for commercial use as a functional food material. This study aims to optimize ultrasound-assisted extraction (UAE) conditions for extracting phenolic compounds from bitter melons using a response surface methodology. A central composite design was used to investigate the effects of three independent variables (ethanol concentration, ultrasonic power, and extraction time) on the responses, extraction yield, total polyphenol content (TPC), and antioxidant activity. The optimal UAE conditions were determined to be 59% and 277 W for 14 min, and the corresponding predicted response values for yield, TPC, and antioxidant activity were 33.42%, 18.73 mg GAE/g, and 66.93%, respectively. UAE showed higher extraction yield, TPC, phenolic content, and antioxidant activity than conventional ethanol extraction. These results suggest that bitter melon phenolic compounds obtained by the UAE could be used as natural antioxidant agent or functional ingredient enhancers in suitable food products.Optimización de la extracción asistida por ultrasonidos de compuestos fenólicos del melón amargo (Momordica charantia) mediante la metodología de superficie de respuesta RESUMENEl melón amargo es rico en compuestos fenólicos y posee un importante potencial para ser usado comercialmente como material alimentario funcional. Con el objetivo de obtener compuestos fenólicos del melón amargo utilizando la metodología de superficie de respuesta, el presente estudio se propuso optimizar las condiciones de extracción asistida por ultrasonidos (UAE). Para ello se utilizó un diseño central compuesto a fin de investigar los efectos de tres variables independientes (concentración de etanol, potencia ultrasónica y tiempo de extracción) en las respuestas, rendimiento de extracción, contenido total de polifenoles (TPC) y actividad antioxidante. Se determinó que las condiciones óptimas de UAE son 59% y 277 W durante 14 minutos, mientras que los correspondientes valores de respuesta previstos para el rendimiento, el TCP y la actividad antioxidante son 33.42%, 18.73 mg GAE/g y 66.93%, respectivamente. Asimismo, se comprobó que la UAE posee mayor rendimiento de extracción, TPC, contenido fenólico y actividad antioxidante que la extracción convencional con etanol. Estos resultados dan cuenta de que los compuestos fenólicos del melón amargo obtenidos mediante UAE pueden utilizarse como agentes antioxidantes naturales o para potenciar ingredientes funcionales en productos alimentarios adecuados.

Optimization Conditions of Ultrasound-Assisted Extraction for Phenolic Compounds and Antioxidant Activity from Rubus alceifolius Poir Leaves

“…However, higher X 1 (400-500W) and extended X 3 (40-55 min) resulted in low ABTS values due to the degradation of phenolics. This is similar to what was obtained for phenolic extraction from bitter melon [ 30 ] and Celastrus hindsii leaves [ 16 ]. Figure 3(f) illustrates the impact of X 2 and X 3 on the ABTS radical scavenging activity.…”

“…The extraction temperature of up to 45°C may increase and support the solubility and diffusion of phenolic compounds in the extraction solvent. However, an increased temperature of >60°C may destruct polyphenolic compounds, causing a decrease in antioxidant activity [ 30 ]. Furthermore, the sample cell membrane may break into small fragments under high extraction temperatures, which leads to increase impurities being extracted, thus a decrease in the recovery of phenolic compounds extracted.…”

“…When the highest ABTS was reached, any further increase in X 2 led to a decrease in the ABTS. This might be due to the effect of high temperature on the nature and structure of the phenolic compounds [ 30 ]. The optimal X 2 and X 3 for the phenolic extraction were found to be at its central level.…”

Optimization of functional compounds extraction from Ginkgo biloba seeds using response surface methodology

“…RSM results can intuitively reflect the influence of different factors and their interacting effect on response value. This method has been used for the extraction optimization of macromolecular substances, such as protein and polysaccharides, and other activity compounds such as phytochemicals or flavanols and polyphenols (Borges et al, 2011;Lee and Yoon, 2021;Siddeeg et al, 2015).…”

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

“…The extracts of freeze-dried and ground bitter melon were prepared using ultrasound-assisted extraction with a probe system and 60% (v/v) ethanol (UAE-P-E) or water (UAE-P-W), ultrasound-assisted extraction with an ultrasonic bath and 60% (v/v) ethanol (UAE-B-E), autoclave extraction with water (AE-W), 60% (v/v) ethanol extraction (EE), and hot-water extraction (HWE). The extraction conditions were selected based on previously reported optimized methods for the extraction of bioactive ingredients from various natural materials [Lee & Yoon, 2021;Suh et al, 2017]. For UAE with the probe system, 2 g of ground sample was added to a certain amount of solvent (60% (v/v) ethanol or distilled water) corresponding to 1:20 (w/v), and extraction was performed using an ultrasonic probe device (KFS-600N, Korprotech, Seoul, South Korea) for 15 min at a constant frequency of 20 kHz and an ultrasonic intensity of 270 W. For UAE-B-E, a ground sample of bitter melon (2 g) was mixed with 40 mL of 60% (v/v) ethanol (1:20, w/v) in an Erlenmeyer flask (100 mL).…”