Study On The Antibacterial Mechanism Of Corylifolinin

This thesis consists of three chapters. The first chapter of antibacterial and antimicrobial mechanism of traditional Chinese medicine were reviewed. The second chapter studies the antibacterial activity of corylifolinin and neobavaisoflavone in traditional Chinese medicine Psoralea corylifolia L. of SA, MRSA, ESBLs-SA, EC, ESBLs-EC, PA inhibition zone, the minimum inhibitory concentration, minimum bactericidal concentration and half inhibitory concentration. in vitro. The third chapter by studying the changing of alkaline phosphatase content, electrical conductivity, the soluble protein concentration, SDS-PAGE and SEM, investigate the mechanism of corylifolinin against SA, MRSA and ESBLs-SA.Chapter 1 Advances of antimicrobial activity and antimicrobial mechanism of traditional Chinese medicineProgress of antimicrobial activity and antimicrobial mechanism of traditional Chinese medicine were summarized.Chapter 2 The antibacterial activity of corylifolinin and neobavaisoflavone in vitroDisc diffusion method(K-B method) was used for the determination of the inhibition zone size(IZ) and the minimum inhibitory concentration(MIC) of corylifolinin and neobavaisoflavone antimicrobial activity. Liquid culture method and streak plate method to determine the minimum bactericidal concentration(MBC). Half inhibitory concentration(IC50) was determined by liquid culture method.The results of inhibition zone size(IZ) showed that corylifolinin and neobavaisoflavone had a relatively strong antibacterial activity against SA, MRSA and ESBLs-SA. At the same concentration, the inhibition zone diameters of corylifolinin is larger than neobavaisoflavone.But for PA, ESBLs-EC and EC had not showed any antimicrobial activity.The minimum inhibitory concentration of corylifolinin against three strains were SA(MIC=0.078 mg/mL), MRSA(MIC=0.156 mg/mL) and ESBLs-SA(MIC=0.078 mg/mL).The minimum inhibitory concentration of neobavaisoflavone against SA, MRSA and ESBLs-SA are all 0.625mg/mL.MBC value of corylifolinin were 0.156, 0.156, 0.078 mg/mL against SA, MRSA and ESBLs-SA respectively. MBC value of neobavaisoflavone were 2.5, 1.25,1.25 mg/mL against SA, MRSA and ESBLs-SA respectively.The IC50 value of corylifolinin were 0.031±0.001, 0.106±0.005 and 0.049±0.002 mg/mL against SA, MRSA and ESBLs-SA respectively; IC50 value of neobavaisoflavone were 0.627±0.005, 0.381±0.002 and 0.359±0.003 mg/mL against SA, MRSA and ESBLs-SA respectively.In summary, corylifolinin and neobavaisoflavone both had relatively strong antibacterial activity against SA, MRSA and ESBLs-SA. Especially corylifolinin had better antibacterial activity in vitro.Chapter 3 The antibacterial mechanism of corylifolininBased on the series of disc diffusion method, liquid culture method and streak plate method measured were used to measure the minimum inhibitory concentration, the minimum bactericidal concentration of corylifolinin, then studied the antibacterial mechanism of corylifolinin.The MIC of corylifolinin showed that the antimicrobial activity against SA,ESBLs-SA is better than MRSA. According to the results of MBC,the MBC of ESBLs-SA is equal to the MIC.In the minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) for the determination of indicators:first of all, the changes of bacteria shape was obvioused by SEM. Next,by means of measuring conductivity(TDS),alkaline phosphatase(AKP), extracellular soluble protein content and SDS-PAGE electrophoresis bands change, thus antibacterial mechanism of corylifolinin were studied.Results showed that bacteria were treated with corylifolinin, the morphology of bacteria was changed significantly.As a result,bacterial was treated with corylifolinin the longer, the more significant changed.The content of alkaline phosphatase, extracellular soluble protein have undergone significant changes. But Little effect on the conductivity of bacteria. SDS-PAGE electrophoresis protein bands were clearly changed, only SA treated with minimum bactericidal concentration.