Effects of Ultrasonic Pre-Treatment on Physicochemical Properties of Sericin Poteins Extracted from Cassava Silkworm Cocoon

Extraction of sericin protein from Cassava silkworm cocoons is beneficial to the value-added utilization of these natural waste resources. However, existing methods still are involved in extensive energy consumption, complex chemicals, or extended periods. Herein, an efficient intermittent ultrasonic pre-treatment strategy has been developed to improve sericin protein production from Cassava silkworm cocoon. The protein is obtained by boiling cocoons in Na₂CO₃ solution after 300 W ultrasonic pre-treatment, and the effect of ultrasonic pre-treatment on the physicochemical properties of sericin protein is investigated. The results show that the protein yields are affected by the ultrasonic power and the ultrasonic time, and the ultrasonic pre-treatment can significantly increase the protein yield compared with that from conventional treatment. The protein is identified as sericin protein in electrophoresis and chromatography patterns. The morphology and particle size analysis reveal that the sonication can disorder protein molecular structure with lower particle size, leading to the change of secondary structure and thermal stability. The cell viability results indicate that the sericin obtained with ultrasonic pre-treatment exhibit excellent cytocompatibility with fibroblast cells after 24 h incubation. In conclusion, this study provides a way for the separation and future application of waste sericin, which may valorize the waste sericin to high-end biomaterials products as well as reduce environmental issues.