关键词: 甘露糖醛酸寡糖, 环丙沙星, 大肠埃希菌, Ca²⁺

Abstract: By investigating the content of ciprofloxacin(CPFX)in Escherichia coli and the effect of mannuronic acid oligosaccharide(MOS)with different concentrations on the inhibitory activity of CPFX against E.coli, the mechanism that MOS sensitize the inhibitory activity of CPFX against E.coli was explored. CPFX and MOS with different concentrations were added into the bacterial suspension and cultured for 150 min at 37 ℃ to observe the bacteriostatic effect. The content of CPFX in the bacteria was determined by HPLC, and the fluorescence intensity of CPFX in the bacteria was observed by confocal laser scanning microscope(CLSM)to verify the above result. The effect of Ca²⁺ on the elevated antimicrobial effect of CPFX with MOS was also investigated. The results showed that when CPFX was- DOI:10.3969/j.issn.1000-1565.2023.02.007甘露糖醛酸寡糖增敏环丙沙星抑制大肠埃希菌机制的研究 谢笑莹¹,郭怀忠^1,2,曹丽军³,马梦楠¹,崔秀彦⁴(1.河北大学 药学院,河北 保定 071002;2.河北省药物质量分析控制重点实验室,河北 保定 071002;3.河北大学附属医院 检验科,河北 保定 071000;4.河北大学附属医院 药学部,河北 保定 071000)摘 要:通过考察大肠埃希菌(Escherichia.coli)体内环丙沙星(ciprofloxacin, CPFX)的含量以及联用不同浓度甘露糖醛酸寡糖(MOS)对CPFX抑制E.coli效果的影响,探讨了MOS增敏CPFX抑制E.coli活性的作用机制.在菌液中加入CPFX和不同质量浓度的MOS,37 ℃培养150 min,观察抑菌效果,并用HPLC法测定E.coli体内CPFX的含量,同时通过激光扫描共聚焦显微镜(CLSM)观察E.coli体内CPFX的荧光强度进行验证.还考察了Ca²⁺对MOS增敏CPFX抑菌效果的影响.结果显示:CPFX与高浓度的MOS联用时,E.coli体内CPFX的含量较低;与较低浓度的MOS联用时,E.coli体内CPFX的含量较高,与其抑菌实验联用MOS高浓度时拮抗,低浓度时增敏的结果一致.Ca²⁺的加入,在一定程度上逆转了高浓度MOS与CPFX的拮抗作用.该研究可为新型抗菌增效剂的开发和抗耐药菌感染的临床应用提供参考.关键词:甘露糖醛酸寡糖;环丙沙星;大肠埃希菌;Ca²⁺中图分类号:R917 文献标志码:A 文章编号:1000-1565(2023)02-0156-07Study on the mechanism of mannuronic acid oligosaccharidesensitizing ciprofloxacin against Escherichia coliXIE Xiaoying¹, GUO Huaizhong^1,2, CAO Lijun³, MA Mengnan¹, CUI Xiuyan⁴(1. College of Pharmaceutical Sciences, Hebei University, Baoding 071002, China; 2. Key Laboratoryof Pharmaceutical Quality Analysis and Control of Hebei Province, Baoding 071002, China; 3. Department of Clinical Laboratory, Affiliated Hospital of Hebei University, Baoding 071000, China;4.Department of Pharmacy,Affiliated Hospital of Hebei University,Baoding 071000,China)Abstract: By investigating the content of ciprofloxacin(CPFX)in Escherichia coli and the effect of mannuronic acid oligosaccharide(MOS)with different concentrations on the inhibitory activity of CPFX against E.coli, the mechanism that MOS sensitize the inhibitory activity of CPFX against E.coli was explored. CPFX and MOS with different concentrations were added into the bacterial suspension and cultured for 150 min at 37 ℃ to observe the bacteriostatic effect. The content of CPFX in the bacteria was determined by HPLC, and the fluorescence intensity of CPFX in the bacteria was observed by confocal laser scanning microscope(CLSM)to verify the above result. The effect of Ca²⁺ on the elevated antimicrobial effect of CPFX with MOS was also investigated. The results showed that when CPFX was- 收稿日期:2022-04-25 基金项目:河北省自然科学基金资助项目(H2021201018,H2016201221);河北省创新能力提升计划(20567605H) 第一作者:谢笑莹(1995—),女,河南商丘人,河北大学在读硕士研究生.E-mail:792270064@qq.com 通信作者:郭怀忠(1968—),男,内蒙古商都人,河北大学教授,博士,主要从事中药质量控制及其药效学研究.E-mail:ghuaizh@aliyun.com第2期谢笑莹等:甘露糖醛酸寡糖增敏环丙沙星抑制大肠埃希菌机制的研究河北大学学报(自然科学版) 第43卷combined with MOS of higher concentration, the content of CPFX in E.coli was lower, however, when with MOS of a lower concentration, the content of CPFX in E.coli was higher. The antagonistic results were consistent with the inhibitory results when MOS was combined under high concentration in the bacteriostatic experiment. The addition of Ca²⁺ reversed the antagonism between high concentration of MOS and CPFX to a certain extent. This study can provide reference for the development of new antimicrobial synergist and clinical application of anti-drug resistant bacteria infection.

Key words: mannuronic acid oligosaccharide, ciprofloxacin, Escherichia coli, Ca²⁺