This study evaluated efficacy of high-intensity ultrasound (HIU) on controlling or stimulating Staphylococcus aureus biofilm. Acoustic pressure distribution on the surface of glass slide cultivated S. aureus biofilm was first simulated as a standardized parameter to reflect sono-effect. When the power of HIU was 240 W with acoustic pressure of −1.38×10⁵ Pa, a reasonably high clearance rate of S. aureus biofilm was achieved (96.02%). As an all-or-nothing technique, the HIU did not cause sublethal or injury of S. aureus but inactivate the cell directly. A further evaluation of HIU-induced stimulation of biofilm was conducted at a low power level (i.e. 60 W with acoustic pressure of −6.91×10⁴ Pa). The low-power-long-duration HIU treatment promoted the formation of S. aureus biofilm and enhanced its resistance as proved by transcriptional changes of genes in S. aureus, including up-regulations of rbf, sigB, lrgA, icaA, icaD, and down-regulation of icaR. These results indicate that the choose of input power is determined during the HIU-based cleaning and processing. Otherwise, the growth of S. aureus and biofilm formation are stimulated when treats by an insufficiently high power of HIU.

本研究评估了高强度超声 (HIU) 对控制或刺激金黄色葡萄球菌生物膜的功效。首先模拟了载玻片培养的金黄色葡萄球菌生物膜表面的声压分布作为反映声效应的标准化参数。当HIU功率为240 W、声压为-1.38×10 ^{5 Pa时，}金黄色葡萄球菌生物膜的清除率相当高（96.02%）。作为一种全有或全无的技术，HIU 不会导致金黄色葡萄球菌亚致死或损伤，而是直接使细胞失活。在低功率水平（即60W，声压为-6.91×10 ⁴ Pa）下进行HIU诱导的生物膜刺激的进一步评估。低功率长时间HIU处理促进了金黄色葡萄球菌生物膜的形成并增强了其抵抗力，金黄色葡萄球菌基因转录变化证明，包括rbf、sigB、lrgA、icaA、icaD和icaR的下调。这些结果表明输入功率的选择是在基于 HIU 的清洁和处理过程中确定的。否则，当 HIU 功率不够高时，会刺激金黄色葡萄球菌的生长和生物膜的形成。