STUDYING FOR PROTEIN EXTRACTION FROM Chlorella vulgaris USING ENZYME - COMBINED ULTRASOUND TECHNIQUES

Abstract

This study investigates using ultrasound technology and commercial enzymes for protein extraction from Vietnam Chlorella vulgaris. The research aims to optimize the combined ultrasound and enzymatic conditions to improve the efficiency and quality of protein extraction. The study was conducted in three main stages: Ultrasound-assisted cell disruption followed by hydrolysis with viscozyme and finally, protein extraction with flavourzyme. The study demonstrates the effectiveness of ultrasound technology in breaking down algal cells and increasing protein extraction yield. The optimal conditions for this stage were identified as pH 8, 50°C temperature, 40 minutes ultrasound time and a 100 g/L ratio of algae to water. The enzyme viscozyme was selected as the appropriate cellulase to enhance the disruption of the cells after ultrasound treatment. The optimal conditions for viscozyme were identified as pH 6, 50°C temperature, 90 minutes enzyme treatment time and 0.75% enzyme concentration. After the cell disruption with viscozyme, flavourzyme was used to extract protein, with the optimal conditions being identified as pH 6.8, 50°C temperature, 2.5 hours treatment time, 380 rpm stirring speed and 2.8% (NH₄)₂SO₄ concentration. The use of inorganic salt (NH₄)₂SO₄ helps to increase the ionic strength, reduce the electrostatic repulsion between protein molecules and thus increase the solubility of protein, improving the extraction yield. The experimental results demonstrate remarkable consistency with the model predictions, highlighting the feasibility of the utilized parameters in the experimental conditions and their applicability in larger-scale settings. The research offers promising results for the production of high-quality protein products from Chlorella vulgaris.