Degradation of carboxymethylcellulose using ultrasound and β-glucanase: Pathways, kinetics and hydrolysates' properties. (1st December 2018) - Hou, Furong
Highlights: Study the effect of ultrasound and β-gulcanase to degrade carboxymethyl cellulose. Ultrasound pretreatment broke CMC chains making it favorable to emzymolysis. The sonoenzymolysis process was the most efficient path to degrade CMC. Ultrasound decreased thermodynamic parameters of hydrolysis reactions. Ultrasound improved to reduce CMC Mw and viscosity without changing primary structure. Abstract: In order to provide an efficient way to degrade carboxymethylcellulose (CMC), three pathways were investigated: enzymolysis, combination of ultrasound pretreatment and enzymolysis, and sonoenzymolysis. Effects of these treatments on enzymatic kinetics, degradation kinetics and properties of degraded CMC were investigated. The degradation degree of CMC was increased by 18.90% and 35.73% with ultrasound pretreatment (at an intensity of 24 W/mL for 30 min) and sonoenzymolysis (at an intensity of 9 W/mL for 50 min), compared with that obtained under the traditional enzymolysis. Analysis of kinetics demonstrated that ultrasound, both pretreatment and combined with β-glucanase, could accelerate CMC degradation. Measurements of rheological properties, molecular weight and structures of CMC hydrolysates revealed that ultrasound broke the glycosidic bond of CMC chains without changing its primary structure. The sonoenzymolysis process was the most efficient method to degrade CMC, with potential to provide a way to obtain CMC with lowest molecular weight or viscosity.