微生物生长传感器药敏试验方法与微量肉汤稀释法的对比研究

渔业生态环境监测与保护、水产病害防治等众多领域的活动都需要对病原微生物进行药敏试验(Antimicrobial susceptibility testing, AST)。本研究以副溶血弧菌(Vibrio parahaemolyticus, VP)为模式微生物，以卡那霉素、四环素、青霉素和恩诺沙星为代表性抗生素，对比研究了微生物生长传感器AST法和标准微量肉汤稀释(Broth microdilution, BMD)AST法的性能特征。结果显示，无论是标准菌株还是来自养殖环境和对虾的分离菌株，分别测定4种抗生素对它们的剂量效应时，2种方法所得最小抑菌浓度(Minimum inhibitory concentration, MIC)值的基本一致率(Essential agreement, EA)都是100%，因而具有高度吻合性。微生物生长传感器AST法测定的MIC值往往不小于BMD AST法的测定结果，表明自动化仪器法的灵敏度高于肉眼观察。比较而言，微生物生长传感器AST法因为能提供细菌生长实时动力学曲线而呈现更高的效率和更多的抗生素响应信息，而且自动化程度高，操作简便，用户友好，因而具有更好的应用推广前景。

A comparative study on microbial growth sensor and broth microdilution for antibiotic susceptibility testing

Antimicrobial susceptibility testing (AST) is of great significance to the assessment of environmental health of fisheries, clinical applications, epidemiological research, etc. Here, the merits of an automated microbial-growth electrical-sensor-based AST method are compared with the standard broth microdilution (BMD) method, using Vibrio parahaemolyticus (VP) as a microorganism model, and tetracycline, kanamycin, enrofloxacin, and penicillin V as antibiotics model. Results show that the essential agreement of the minimal inhibitory concentration (MIC) obtained with the two methods is 100%, for both standard and isolated VP strains. The MICs obtained with the automated microbial-growth electrical-sensor-based AST method are no lower than those obtained with the BMD method, indicating that the senor is more sensitive than visual detection in identifying critical values. In addition, a dynamic sensorgram of the automated microbial-growth electrical-sensor-based AST provides more detailed information on the antibiotic activity at different growth stages. Because of the outstanding merits of sensitivity, efficiency, and user-friendly operation, microbial-growth electrical-sensor-based AST is a promising method that can be applied widely in the future.