隐丹参酮抑菌作用机制研究

目的研究隐丹参酮对金黄色葡萄球菌(SA)、耐甲氧西林金黄色葡萄球菌(MRSA)、β-内酰胺酶阳性的金黄色葡萄球菌(ESBLs-SA)3种金黄色葡萄球菌的抑菌活性及抑菌机制。方法采用纸片扩散法测定隐丹参酮的抑菌圈和最低抑菌浓度(MIC),液体培养法测定其半数抑菌浓度(IC50值),并通过测定隐丹参酮与3种金黄色葡萄球菌作用前后电导率变化、碱性磷酸酶(AKP)的含量变化、胞外蛋白含量变化和SDS-PAGE电泳蛋白谱带变化,初步阐明隐丹参酮对金黄色葡萄球菌、耐甲氧西林金黄色葡萄球菌、β-内酰胺酶阳性的金黄色葡萄球菌的抑菌机制。结果由抑菌圈、最低抑菌浓度和半数抑菌浓度可以看出,隐丹参酮对金黄色葡萄球菌的抑制作用略强于耐甲氧西林金黄色葡萄球菌和β-内酰胺酶阳性的金黄色葡萄球菌;经隐丹参酮作用后,3种金葡菌的电导率、碱性磷酸酶及胞外蛋白含量均增大,SDS-PAGE电泳显示蛋白谱带也明显发生变化。结论隐丹参酮对金黄色葡萄球菌、耐甲氧西林金黄色葡萄球菌和β-内酰胺酶阳性的金黄色葡萄球菌具有明显的抑制作用,隐丹参酮破坏细菌细胞壁和细胞膜的结构,导致细胞膜通透性增加,进而使细胞内容物外泄;同时隐丹参酮对细菌蛋白质的合成有一定影响,使菌体内蛋白质减少,影响和阻碍细胞内蛋白质的表达,最终导致细菌正常生理功能的丧失。

Antibacterial Mechanism of Cryptotanshinone

OBJECTIVE To study the antimicrobial activity and antibacterial mechanisms of cryptotanshinone against SA, MRSA and ESBL_S-SA. METHODS MIC value was determined by disc diffusion method. IC₅₀ value was determined by liquid culture. The antibacterial mechanisms of cryptotanshinone were investigated by determining the changes in electric conductivity, concentration of AKP, protein content, and the changes of protein electrophoretic bands in SDS-PAGE. RESULTS The antibacterial rings, MIC and IC₅₀ values showed that the antimicrobial activity against SA was better than that against MRSA and ESBLs-SA. Treated with cryptotanshinone, the electric conductivity, concentration of AKP, and protein content were increased, and protein bands in SDS-PAGE were changed obviously. CONCLUSION Cryptotanshinone significantly inhibits SA, MRSA and ESBLs-SA and can damage the structures of cell wall and cell membrane, which results in the increase of permeability of cell membrane and release of cell components. Cryptotanshinone can influence the synthesis of bacteria protein, destroy the protein or reject the anabolism or expression of the protein, and finally leads to the loss of normal physiological function of bacterium.