洋葱伯克霍尔德菌群(Bcc)及干扰菌在不同增菌培养基中的生长研究

Study on the Growth of Burkholderia cepacia Complex(Bcc)and Interfering Bacteria in Diff erent Pre-incubation Media

目的:考察Bcc以及Bcc与干扰菌的混合物在不同的增菌培养基中能否生长和增殖;探讨不同的Bcc菌种对增菌培养基的营养需求和抗生素的耐受是否存在差异。方法:将Bcc的代表菌株、干扰菌以及Bcc与干扰菌的混合物分别接种至TSB、10倍稀释的TSB、添加10 mg·L^(-1)庆大霉素的TSB和添加250000 U·L^(-1)多粘菌素B的TSB中培养,划线分离至选择性培养基上观察结果,并对可疑菌落进行分离和鉴定。结果:只接种Bcc的4种增菌培养基均能使之良好地增殖。低量的Bcc(约102 cfu)与高量的干扰菌(104 cfu)的混合接种,除了神秘伯克霍尔德菌CMCC(B)23010外,4种增菌培养基能使Bcc增殖并被检出。结论:添加抗生素的TSB与未添加抗生素的相比没有表现出明显的优势。TSB可以作为Bcc检验时的增菌培养基使用。生长缓慢且活力弱的Bcc菌株在特定条件下有可能会被漏检。

Objective:To investigate whether Bcc could grow and proliferate in diff erent Pre-incubation media and mixed with interfering strains,and discuss whether there are differences in nutritional requirements and antibiotic tolerance of diff erent Bcc strains for pre-incubation media.Methods:The representative strains of Bcc,interfering strains,the mixture of Bcc and interfering strains were inoculated into TSB,1/10 TSB,TSB added with 10 mg·L^(-1) gentamicin and TSB added with 250000 U·L^(-1) polymyxin B,respectively.Cultures streaked and separated on selective medium,and suspicious colonies were isolated and identified.Results:All Bcc strains grew well in the four diff erernt incubation media.Except Burkholderia aenigmatica CMCC(B)23010,when the low amount of Bcc(about 102 cfu)and high amount of interfering bacteria(104 cfu)were mixed inoculated,Bcc proliferated in all 4 kinds of incubation media were detected.Conclusion:TSB with antibiotics did not show signifi cant advantage compared with those without antibiotics for pre-incubation of Bcc.TSB could be used as an enrichment medium for Bcc testing.Bcc strains with slow growth or low viability could be missed under certain conditions.