Optimization of Ultrasound-Assisted Protein Extraction from Rice Bran using Deep Eutectic Solvents

Abstract

This study investigates the extraction of proteins from rice bran, a cost-effective plant-based source known for its hypoallergenic and nutraceutical properties, specifically focusing on albumin, globulin, prolamin, and glutelin. The research utilizes deep eutectic solvents (DES) coupled with ultrasound assistance to enhance the value of rice bran. Four different DES types were screened to identify the most effective one. The Response Surface Methodology (RSM) was employed to assess the influence of three operational variables—temperature, extraction time, and the ratio of rice bran to DES—on protein yield. Optimal conditions were identified as 1 gram of rice bran, 15 milliliters of DES, 50 minutes of extraction time, and an extraction temperature of 60°C, resulting in the highest protein yield. FTIR analysis confirmed the presence of amino acids at 1648.40 cm-1. The Bradford method revealed the maximum protein content in rice bran as 8.95%. Electrophoresis analysis indicated predominant protein bands at molecular weights of 55 kDa, 43 kDa, 34 kDa, and 17 kDa. The findings suggest that using deep eutectic solvents for protein extraction from rice bran, an eco-friendly approach, enhances its potential as a functional food ingredient.