Extraction of ferulic acid from rice bran using NADES‐ultrasound‐assisted extraction: Kinetics and optimization

Abstract

The application of natural deep eutectic solvents (NADES) has been studied for the ultrasound‐assisted extraction of ferulic acid (FA) from Defatted rice bran at 25 kHz. Choline chloride‐hydrogen bond acceptor and D‐glucose‐hydrogen bond donor in 1:1 (w/v) ratio with 50% NADES and 1:20 (w/v) solute to solvent ratio has been employed. Essential ultrasonic parameters such as power, temperature, and duty cycle have been optimized. The kinetics have been studied using Peleg's model to predict the extraction yield of FA. The experimental yield was found to be in agreement with the predicted yield of FA, suggesting a good fit for the model. The maximum yield of 9.34 mg/g was estimated through optimized parameters of 50 W power, 50°C temperature, 50 % duty cycle and extraction time of 16 mins. At the same time, the obtained yield of FA in conventional extraction and NADES extraction (without ultrasound) was 3.33 mg/g and 8.71 mg/g, respectively. The proposed NADES for the ultrasound‐assisted extraction of FA was a superior alternative in terms of less time, greener solvent, and high yield.

Practical Application

Ultrasound‐assisted extraction is a green method that is commonly used for the extraction of natural ingredients. In this study, the NADES mixture was irradiated with ultrasound to extract the maximum amount of ferulic acid. Various parameters have been studied by both experimentally as well as kinetically. Peleg's model has been used for the kinetic study. This greener approach of NADES‐ultrasound‐assisted extraction showed the highest yield of ferulic acid compared with other extraction methods. Also, the extracted ferulic acid finds application in various industries.