Continuous and pulsed ultrasound-assisted extraction of carob’s antioxidants: Processing parameters optimization and identification of polyphenolic composition

Abstract

Highlights CUAE and PUAE parameters were optimized by the maximization of the yield in TPC. Compared to conventional methods, UAE offered a higher yield of antioxidants. Gallic acid was the most abundant polyphenolic compound in carob pulp extracts. Solvent concentration was the most influential processing parameter. DPA-6S demonstrated the best ability to recuperate the target analytes.

Ultrasound Assisted Extraction of Polyphenols from Ripe Carob Pods (Ceratonia siliqua L.): Combined Designs for Screening and Optimizing the Processing Parameters

“…It means that an increase or decrease of polyphenols concentration was observed when X 3 and X 4 were changed from lower to higher level. This behavior was similarly reported in a recent study dealing with ultrasound extractions from carob pods, in which solvent concentration and solid to solvent ratio were among the three most dominant factors that influenced the polyphenols recovery, while, conversely to our finding, the other determinant factor was the sonication power [17]. Probably, this difference could be ascribed to the use by Christou et al [17] of an ultrasonic probe system in their experiment; indeed, a previous research have demonstrated that, when an ultrasonic water bath is employed for extracting D-pinitol from carob pods, the sonication power is not statistically significant [19].…”

“…Among them, ultrasound assisted extraction 2 of 13 (UAE) is engaging for its simplicity and low cost of equipment [14,15]; it is much quicker than conventional methods, because acoustic cavitations of power US (preferably in the frequencies range 18-100 kHz) cause cell walls disruption, increasing mass transfer and favoring solvent access to the cell content [16]. The efficiency of UAE is generally influenced by several factors, including solvent-solid ratio, solvent type and concentration, particle size, and extraction time and temperature [17]. Many researches have shown that the highest extraction of polyphenols and other bioactive compounds was obtained with ultrasound technology and the application of suitable optimization modelling was essential to identify the optimized extraction conditions [17][18][19].…”

“…The efficiency of UAE is generally influenced by several factors, including solvent-solid ratio, solvent type and concentration, particle size, and extraction time and temperature [17]. Many researches have shown that the highest extraction of polyphenols and other bioactive compounds was obtained with ultrasound technology and the application of suitable optimization modelling was essential to identify the optimized extraction conditions [17][18][19].…”

Customized Deep Eutectic Solvents as Green Extractants for Ultrasonic-Assisted Enhanced Extraction of Phenolic Antioxidants from Dogbane Leaf-Tea

“…Experimental Designs 2.6.1. Full Factorial Design Experiments Full factorial design (FFD) experiments designed by Design Expert 10.0.0 software (Sta-Ease, Minneapolis, MN, USA) were conducted for initial screening of key UAE parameters [13,26]. A five-factor two-level FFD experimental was carried out to investigate the influences of water content in DES (A), liquid to solid ratio (B), extraction time (C), ultrasonication power (D), and ultrasonication temperature (E) on TPC and TFC (Table S1).…”

Process Efficiency and Energy Consumption during the Ultrasound-Assisted Extraction of Bioactive Substances from Hawthorn Berries

“…There was no significant difference between continuous and pulsing irradiation despite the great difference in energy consumption (190 kJ vs. 80 kJ). On the other hand, Christou et al [36] during polyphenol recovery from mature and immature carobs, achieved a slightly higher efficiency when UAE was performed in the pulsed mode. The ultrasonic processor runs intermittently during pulse ultrasound assisted extraction (PUAE).…”