title: Synergetic effects of ultrasound and slightly acidic electrolyzed water against Staphylococcus aureus evaluated by flow cytometry and electron microscopy.
abstract: This study evaluated the synergetic effects of ultrasound and slightly acidic electrolyzed water (SAEW) on the inactivation of Staphylococcus aureus using flow cytometry and electron microscopy. The individual ultrasound treatment for 10min only resulted in 0.36logCFU/mL reductions of S. aureus, while the SAEW treatment alone for 10min resulted in 3.06logCFU/mL reductions. The log reductions caused by combined treatment were enhanced to 3.68logCFU/mL, which were greater than the sum of individual treatments. This phenomenon was referred to as synergistic effects. FCM analysis distinguished live and dead cells as well as revealed dynamic changes in the physiological states of S. aureus after different treatments. The combined treatment greatly reduced the number of viable but nonculturable (VBNC) bacteria to 0.07%; in contrast, a single ultrasound treatment for 10min induced the formation of VBNC cells to 45.75%. Scanning and transmission electron microscopy analysis revealed that greater damage to the appearance and ultrastructure of S. aureus were achieved after combined ultrasound-SAEW treatment compared to either treatment alone. These results indicated that combining ultrasound with SAEW is a promising sterilization technology with potential uses for environmental remediation and food preservation.
authors: Department of Food Science and Nutrition, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, Zhejiang, China.
authors: Jiao
authors: J
authors: Li
authors: Department of Food Science and Nutrition, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, Zhejiang, China. Electronic address: tding@zju.edu.cn.
authors: Tian
authors: T
authors: Ding
authors: Department of Food Science and Nutrition, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, Zhejiang, China.
authors: Xinyu
authors: X
authors: Liao
authors: Department of Food Science and Nutrition, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, Zhejiang, China.
authors: Shiguo
authors: S
authors: Chen
authors: Department of Food Science and Nutrition, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, Zhejiang, China.
authors: Xingqian
authors: X
authors: Ye
authors: Department of Food Science and Nutrition, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, Zhejiang, China. Electronic address: dhliu@zju.edu.cn.
authors: Donghong
authors: D
authors: Liu
mesh_terms: D004572:Electrolysis; D005434:Flow Cytometry; D006863:Hydrogen-Ion Concentration; D050296:Microbial Viability / Q000187:drug effects; D008854:Microscopy, Electron; D013211:Staphylococcus aureus / Q000166:cytology / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D013242:Sterilization / Q000379:methods*; D000069453:Ultrasonic Waves; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water
keywords: Electron microscopy; Flow cytometry; Slightly acidic electrolyzed water; Staphylococcus aureus; Synergetic effects; Ultrasound