Antimicrobial films are widely used in food and other fields. The present work established a method of preparing antimicrobial films made of calcium alginate and lysozyme. For the sake of the optimization of antimicrobial effect, sonication was applied to increase the immobilization efficiency. Different ultrasonic power and treatment duration were studied. With the assistant of sonication, lysozyme immobilization rate was speeded up and the amount of lysozyme immobilized on the supporters was increased. The catalytic activity of the antimicrobial film was measured using the turbidimetric assay and reached the maximum at 147.8 W. The antimicrobial activity determined by the inhibition zone test was also promoted by sonication. To explore the mechanism of the ultrasonic effect on the lysozyme immobilization, lysozyme structures alteration before and after ultrasonic treatment was considered. The circular dichroism and fluorescence spectra illustrated that sonication affected the secondary and tertiary structures of lysozyme. The changes in the enzyme structures may lead to the improvement of the enzymatic activity. The impact of sonication on the microstructure of the films was investigated by the scanning electron microscope. The film surface showed some cracks after sonication that increased the superficial area accordingly.

抗菌膜广泛用于食品和其他领域。本工作建立了一种由藻酸钙和溶菌酶制成的抗菌膜的制备方法。为了优化抗菌效果，进行了超声处理以提高固定效率。研究了不同的超声功率和治疗时间。在超声处理的辅助下，加快了溶菌酶的固定速度，并增加了固定在支持物上的溶菌酶的数量。使用比浊测定法测量抗菌膜的催化活性，并在147.8 W时达到最大值。超声处理也可促进由抑制区测试确定的抗菌活性。为了探索超声波作用对溶菌酶固定化的机理，考虑了超声处理前后溶菌酶结构的改变。圆二色性和荧光光谱表明，超声处理影响了溶菌酶的二级和三级结构。酶结构的改变可导致酶活性的提高。通过扫描电子显微镜研究了超声处理对薄膜微观结构的影响。超声处理后，薄膜表面显示出一些裂纹，相应地增加了表面面积。通过扫描电子显微镜研究了超声处理对薄膜微观结构的影响。超声处理后，薄膜表面显示出一些裂纹，相应地增加了表面面积。通过扫描电子显微镜研究了超声处理对薄膜微观结构的影响。超声处理后，薄膜表面显示出一些裂纹，相应地增加了表面面积。