[Objective] In order to provide the theoretical basis for clinical application of the bacteriocin Subticinl 12 secreted by Bacillus subtilis, a research was conducted on bacteriostatic activity of bacteriocin Subticinl 12 against Staphylococcus aureus CVCC 1885 in vitro and in vivo. [Method] Bacteriostasis in vitro: Subticin112, oxytetracycline, penicillin, vancomycin, neomycin, strepomycin and gentamicin in the same effective weight were dissolved into equal volume of sterile saline, respectively. Then the agar diffusion method was used to compare the bacteriostatic activity of the medicines against S. auretis. Bacteriostasis in vivo: 120 SPF-class KM male mice (weighted from 18 g to 22 g) were divided into six groups, they were blank control group, negative control group, oxytetracycline treating group and three Subticin112 treating groups. After the beginning of the experiment, every mouse in each group was orallly administrated 0.4 mL different concentrations of medicine or sterile saline every other 8 hours, after 3 times of oral administration, the mice in each group were intraperitoneal injected at the absolute lethal dose of S. aureus or sterile saline. At the end of the experiment, the mortality was calculated, the proinflammatory cytokines and the cfu values of S. aureus in the peritoneum of the mice were determined, and then the histopathological changes of the tissues were observed. [Result] Bacteriostasis in vitro: Subticin112 expressed a fine bacteriostatic activity compared to the same concentration of other medicines. The bacteriostatic activity of Subticin112 was highly significantly better than that of vancomycin and neomycin (P0.05). Bacteriostasis in vivo: after the experiment, the mortality in negative control group was 100%, while which was 30% in low-dose Subticin112 treating group, and other groups did not have dead mice. The medicine treating groups showed a low concentration of the proinflammatory cytokines (P)的金黄色葡萄球菌或无菌生理盐水.试验结束后测定死亡率、促炎性细胞因子水平、腹腔液金黄色葡萄球菌浓度并制作病理组织切片进行观察.[结果]体外抑菌:与抗生素相比,相同浓度的Subticin112对金黄色葡萄球菌具有很好的抑菌活性,其中与万古霉素和新霉素相比,Subticin112对该致病菌的抑制活性更好,且差异极显著(P0.05).体内抑菌:试验结束后,阴性对照组小鼠死亡率为 100%,低浓度 Subticin112治疗组为30%,其它组小鼠均无死亡;与阴性对照组相比,药物治疗组小鼠的促炎性细胞因子(IL-1 β,IL-6和TNF-α)水平均有下降,差异显著(P<0.05),药物治疗组小鼠腹腔液中的金黄色葡萄球菌浓度也均有下降,差异极显著(P<0.01),且呈明显的量效关系;病理切片显示朋性对照组肝脏和脾脏具有明显的病变,而药物治疗组病变轻微或无病变.[结论]可以得出细菌素Subticin112在动物体内外对金黄色葡萄球菌 CVCC 1885 均具有较好的抑菌活性,具备开发为新型抗菌药物的潜力.
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