纳米银溶胶对变异链球菌标准株及耐氟株抗菌性的研究

The research on antibacterial activities of silver colloid nanoparticles to standard strain and fluoride-resistant strain of Streptococcus mutans

目的探讨葡萄糖和次磷酸钠制备的2种纳米银溶胶对变异链球菌标准株及耐氟株的抗菌作用。方法用纸片扩散法和肉汤微稀释法,测定葡萄糖和次磷酸钠分别还原硝酸银制备的2种纳米银溶胶对标准株及耐氟株的抗菌效果。结果葡萄糖制备的银溶胶对标准株及耐氟株的抑菌圈直径分别为(20.87±0.66)、(19.68±0.86)mm,最小抑菌浓度(MIC)为(2.08±0.90)、(2.60±0.90)μg/mL;次磷酸钠制备的银溶胶对实验菌的抑菌圈直径分别为(14.86±0.43)、(14.19±0.50)mm,MIC为(35.15±12.18)、(56.24±24.36)μg/mL。2种溶胶对实验菌均有抗菌性,其中前者的抗菌性高于后者且差异显著(P<0.05);同种溶胶对标准株和耐氟株抗菌性的差异不显著(P>0.05)。结论葡萄糖和次磷酸钠制备的2种纳米银溶胶对变异链球菌标准株及耐氟株均有较高的抗菌性,且前者的抗菌性明显优于后者。

Objective To investigate the antibacterial effects of two kinds of silver colloid nanoparticles which were prepared with glucose and sodium hypopbospbite against standard strain and fluoride-resistant strain of Streptococcus mutans. Methods Two kinds of silver colloid nanoparticles were prepared by reducing silver nitrate with glucose and sodium hypophosphite as reducing agents. We used the disk diffusion method and broth microdilution method to find out the antimicrobial properties of these two silver nanoparticles to standard strain and fluoride-resistant strain of Streptococcus mutans. Results The mean diameters of inhibition zone of the former nanoparticles to test bacteria were （20.87 ± 0.66）, （19.68 ± 0.86） mm respectively, and minimum inhibitory concentrations （MICs）were （2.08 ± 0.90） μg/mL, （2.60 ± 0.90） μg/mL; For the latter nanoparticles, diameters of inhibition zone to test bacteria were （ 14.86 ± 0.43 ） mm, （ 14.19 ± 0.50） mm, MICs were （ 35.15 ± 12.18） μg/mL, （ 56.24 ± 24.36） μg/mL. Between the two kinds of silver colloid, antibacterial property of the former was higher than the latter and the difference was quite obvious. There was no significant difference in antibacterial property against standard strain and fluoride-resistant strain in one kind of solution. Conclusions Two kinds of silver colloid nanoparticles made with glucose and sodium hypophosphite as the reducing agents respectively exhibited high antibacte- rial effects against standard strain and fluoride-resistant strain of Streptococcus mutans,and the former was better than the latter.