|
|
|
| Antibacterial and Antibiofilm Mechanism of Ultrasound in Combination with Heat against Staphylococcus aureus |
| SUN Jinyue, WANG Debao, SUN Zhilan, XIONG Qiang, LIU Fang, XU Weimin, WANG Daoying, LI Kunpeng |
| 1.Institute of Agricultural Products Processing, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; 2.College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China; 3.Xuzhou Datun Lijia Food Co. Ltd, Xuzhou 221618, China |
|
|
|
|
Abstract This study was devised to investigate the bactericidal effect and mechanism of ultrasound (US) in combination with heat (HT) against Staphylococcus aureus planktonic and biofilm cells. The results showed that US combined with HT at 70 ℃ (UH70) significantly reduced the counts of Staphylococcus aureus planktonic and biofilm cells (P < 0.05). Scanning electron microscopy (SEM) showed that UH70 obviously damaged the cell membrane. Confocal laser scanning microscopy (CLSM) indicated that UH70 sharply increased the permeability of the cell membrane, thereby causing a significant increase in the extracellular concentrations of ATP, nucleic acid and protein (P < 0.05). In addition, UH70 significantly decreased the activity of intracellular respiratory chain dehydrogenase and the concentration of extracellular polysaccharide in the biofilm (P < 0.05). In conclusion, US combined with HT could have stronger bactericidal effect than either alone. The synergistic bactericidal mechanism may be related to destroying the cell membrane, altering cell membrane permeability, causing the leakage of ATP, nucleic acid and protein out of the cells, and reducing the activity of respiratory chain dehydrogenase.
|
|
|
|
|
|
|
|
|
|
|
2021, Vol. 35 
