乌蕨醇提物联合抗生素对CTX-M型产ESBLs大肠杆菌的作用研究

Study on the Effects of the Ethanol Extraction of Stenolma chusanum Ching Combined with Antibiotics against the E.coli with β-lactamase Gene CTX-M

为了探讨乌蕨醇提物的药效以及与抗生素联用对CTX-M型产ESBLs大肠杆菌的体外抑菌效果,为乌蕨的综合开发利用和防治此类耐药大肠杆菌感染提供一定的参考依据。用70%乙醇冷浸乌蕨粉末两次,每次7 d,过滤蒸干后用浓度为4%二甲基亚砜(DMSO)溶解,最终药物浓度为0.064 g/m L。先用二倍微量稀释法测定乌蕨醇提物和15种抗生素对2株受试菌的最小抑菌浓度(MIC),再用微量棋盘稀释法进行联合药敏试验,测定乌蕨醇提物与抗生素联用的分级抑菌浓度指数(FICI)。结果:(1)号菌株:乌蕨醇提物与磷霉素的FICI为0.281,表现为协同作用;与头孢曲松钠、头孢他啶、头孢噻肟钠、头孢噻呋钠、阿莫西林、磺胺间甲氧嘧啶、林可霉素、氟苯尼考、利福平的FICI分别为0.563、0.516、0.516、0.563、0.75、0.625、0.625、0.625、0.75,均表现为相加作用;与氟喹诺酮类药物的FICI范围为9~65,均表现为拮抗作用;(2)号菌株:乌蕨醇提物与磷霉素、磺胺间甲氧嘧啶、林可霉素的FICI分别为0.281、0.375、0.5,均表现为协同作用;与头孢曲松钠、头孢他啶、头孢噻肟钠、头孢噻呋钠、阿莫西林、氟苯尼考、利福平的FICI分别为0.504、0.516、0.504、0.502、0.504、0.625、0.75,均表现为相加作用;与氟喹诺酮类药物的FICI范围为4.5~32.5,均表现为拮抗作用。

To investigate the antibacterial effect of the ethanol extraction of Stenolma chusanum Ching and its combination with antibacterial drugs against the E.coli with β-lactamase gene CTX-M in vitro,and provide primary references both to the prevention and treatment of thedrug-resistance E.coli infection and the further development of Stenolma chusanum Ching.To use the ethanol（70% volume faction） to soak the powder of Stenolma chusanum Ching for 7 days at room temperature twice,and then the extractions were evaporated after filtration.The extraction was then dissolved in dimethyl sulfoxide solution（4% volume faction） to make the liquid medicine（0.064 g/m L）.The minimal inhibition concentration（MIC） of the ethanol extraction of Stenolma chusanum Ching and antibacterial drugs was tested against two strains of E.coli withβ-lactamase gene CTX-M using two-fold micro-dilution method.Furthermore,the fractional inhibitory concentrations index（FICI） of the ethanol extraction of Stenolma chusanum Ching combined with antibacterial drugs was measured.For No.1 strain,the ethanol extraction of Stenolma chusanum Ching combined with fosfomycin showed synergistic effect,and the FICI is 0.281; Its combination with ceftriaxone sodium,ceftazidime,cefotaxime sodium,ceftiofur sodium,amoxicillin,sulfamonomethoxine,lincomycin,florfenicol,and rifampicin showed additive effect,and the FICI were 0.563,0.516,0.516,0.563,0.75,0.625,0.625,0.625,and 0.75,respectively.Its combination with fluoroquinolones antibiotics showed antagonism effect,and the FICI raged from 9 to 65.For No.2 strain,the ethanol extraction of Stenolma chusanum Ching combined with fosfomycin,sulfamonomethoxine,and lincomycin showed synergistic effect,and the FICI were 0.281,0.375,and 0.5,respectively.Its combination with ceftriaxone sodium,ceftazidime,cefotaxime sodium,ceftiofur sodium,amoxicillin,florfenicol,and rifampicin showed additive effect,and the FICIwere 0.504,0.516,0.504,0.502,0.504,0.625,and 0.75,respectively.Its combination with fluoroquinolones antibiotics showed antagonism effect,and the FICI raged from 9 to 65.