香港海鸥形菌对理化生因子抵抗力的实验研究

Sensitivity of Laribacter hongkongensis to selected physical and chemical factors

目的了解香港海鸥形菌(LH)对理化生因子的抵抗力。方法用紫外线、高温、干燥、pH、常用多种化学消毒剂及部分抗菌药物处理两株分离于病人的香港海鸥形菌,定量观察其生长情况。结果温度≥56℃即可灭活香港海鸥形菌;紫外线照射30s杀灭率>90%,照射20min可完全灭菌;菌株在pH>8.5或<5.0条件下不能存活,最适生存pH范围为5.5～8.5;在3%以上盐浓度的肉汤中不生长;对化学消毒剂和干燥较敏感,除对2%碳酸氢钠、2%来苏儿、0.1%迭氮钠和70%乙醇有一定耐受力外,其余消毒剂均可在30s内杀灭该菌;香港海鸥形菌在自然干燥后15min即全部死亡;在18种常见抗菌药物中,仅对头孢噻吩、头孢哌酮、氨苄西林、头孢唑啉、头孢他啶、克林霉素耐药,其余均敏感。结论香港海鸥形菌对多数理化生因子抵抗力较弱,常用的消毒剂能够有效杀灭LH。

Objective To study the resistance of Laribacter hongkongensis to physico-chemical factors and some antimicrobial agents.Methods Two strains of Laribacter hongkongensis isolated from patients with acute diarrhea were subjected to the treatment with ultraviolet light（UV）,heat,acid/base,disinfectants or antibiotics.The growth of the treated cells was quantitatively determined.Results All Laribacter hongkongensis were killed at the temperature above 56℃.After exposure to UV for 30 seconds,the average killing rate was above 90%,and the killing rate was 100% after 20 minutes of treatment.The bacteria were all killed at the pH 5.5 or 8.5.At the salt concentration of 3%,all bacteria were killed.The bacteria were also sensitive to disinfectants and dryness.General purpose disinfectants could kill the bacteria within 0.5 minutes.A certain degree of resistance to 2% sodium bicarbonate,2% Lysol,0.1%NaN3 and 70% ethanol was found.The bacteria were also killed under the condition of drying for 15 min.Among the 18 antibiotics being tested,Laribacter hongkongensis was resistant to cefalotin,cefoperazone,ampicillin,cefazolin,ceftazidime,clindamycin.Conclusion The resistance of Laribacter hongkongensis is relatively weak to physical agents,chemical disinfectants and biological factors.The bacteria can be killed by the routine disinfection process.