不同测定方法对聚维酮碘杀菌效果的比较研究

Bactericidal Efficacy Comparison of Povidone Iodine on Aeromonas hydrophila between Detection Methods

以6株黄鳝源嗜水气单胞菌分离株作为受试菌,研究聚维酮碘在两种测定方法下的杀菌率、有效碘含量,及其对黄鳝的急性毒性,评价不同测定方法的准确性及应用安全性。试验结果显示,采用试管二倍稀释法,在溶菌肉汤、营养肉汤和双倍浓度营养肉汤培养基中,聚维酮碘对6株菌的24h最小抑菌质量浓度和最小杀菌质量浓度均为24g/L(溶菌肉汤=营养肉汤≥双倍浓度营养肉汤)。采用直接作用法时,5mg/L和10mg/L聚维酮碘在10min内的杀菌率分别为99.99%、100%。试管二倍稀释法中有效碘的含量(溶菌肉汤>营养肉汤>双倍浓度营养肉汤)也远低于直接作用法,且有效碘含量在24h后均下降。聚维酮碘对黄鳝的24h半致死质量浓度为173.91mg/L,这一质量浓度远高于直接作用法测定的有效杀菌质量浓度。试验结果表明,聚维酮碘对嗜水气单胞菌具有良好的杀灭性,且在黄鳝养殖中可安全使用。但其有效性易受有机物影响,故在水产养殖中推荐使用直接作用法来测定其有效杀菌质量浓度。

The bactericidal efficacy of povidone iodine（PVPI）on Aeromonas hydrophila and free iodine content of povidone iodine solution were detected and acute toxicity of PVPI to ricefield eel（Monopterus albus）was studied by two methods.The results showed that the minimum inhibitory concentrations and minimum bactericidal concentrations of PVPI in Luria-Bertani（LB）,nutrient broth（NB）and double nutrient broth（DNB）were all in the range of 2—4 g/L（LB = NB ≥ DNB）by a tube double dilution method.Using direct acting method,however,5 mg/L and 10 mg/L of PVPI eradicated 99.99% of and 100%of A.hydrophilain 10 min,respectively.The much lower contents of free iodine obtained were detected by tube double dilution method（LB 〉NB 〉DNB）than that by direct acting method,and the free iodine in all tests was declined after 24 hours.The 24 h-LC50 of PVPI on rice field eel was 173.91 mg/L,much higher than effective bactericidal concentration detected by direct acting method.The findings confirmed the great bactericidal efficacy of PVPI on A.hydrophila and the safety of PVPI in ricefield eel culture.However,the bactericidal efficacy of PVPI was susceptible to organic matter in environment,so it is recommended to use the direct effect method to determine the effective bactericidal concentration in aquaculture.