In Vitro Susceptibility Of Glycyrrhiza Or Combination With Fluconazole On The Candida

ChapterⅠ The effect of Glycyrrhiza on Candida albicansObjectiveTo investigate the inhibitory and killing effects of glycyrrhiza on Candida albicans.MethodsRPMI1640 medium microdilution assay(M27-Ed4[1])issued by Clinical and Laboratory Standards Institute(CLSI)was performed to identify the minimal inhibitory concentration(MIC50)of glycyrrhiza(granule)and Fluconazole against wild type Candida albicans(SC5314);the colony number of Candida albicans treated with different concentrations of glycyrrhiza and/or fluconazole was observed;the morphology of mycelia under the influence of glycyrrhiza was observed under the microscope at different temperatures;evans blue staining was used to compare the activity difference of Candida albicans before and after treated by glycyrrhiza with or without fluconazole;Ocelloscope was used to dynamically monitor the growth rate of Candida albicans under the effect of glycyrrhiza.Result1、The MIC value of glycyrrhiza is 128 mg/ml,and the MIC value of glycyrrhiza combined with fluconazole becomes 8 mg/ml;2、Combination of drugs can significantly inhibit the growth of Candida.the Candida colonies were significantly reduced on tablets where liquorice 128mg/ml and fluconazole 64ug/ml were combined;When the concentration of the two decreased to 32mg/ml and 16ug/ml,respectively,the effect was obviously weakened;3、Candida albicans treated with glycyrrhiza and/or fluconazole,presented blue staining in varying degrees,and the staining was more obvious when the two were combined;4、Glycyrrhiza(256mg/ml)could significantly inhibit the mycelial growth of Candida albicans at different time points under 30℃ and 37℃;5、When the concentration of glycyrrhiza reached 16mg/ml,the growth rate of Candida albicans was inhibited,but the inhibition only lasted for about 5 hours;when the concentration reached 32mg/ml,the inhibition could last for more than 12 hours;when the concentration was above 64mg/mL,glycyrrhiza could completely inhibit the growth of Candida albicans,which could last for more than 19 hours.Conclusion1、Glycyrrhiza has anti-Candida albicans effect,and it has obvious synergistic effect combined with fluconazole;2、At different temperatures,glycyrrhiza had significant ability to inhibit the mycelium formation of Candida albicans,and different concentrations of glycyrrhiza had different inhibitory degrees on the growth rate of Candida albicans.With the concentration of glycyrrhiza increased,the degree of inhibition increased significantly.3、Glycyrrhiza in combination with fluconazole can influence the activity and growth rate of Candida albicans.Chapter Ⅱ In vitro susceptibility of glycyrrhiza monomer or in combination with Fluconazole on the CandidaObjectiveTo investigate the antifungal effects of licochalconeA,isoliquiritigenin,18a-glycyrrhetinic acid or in combination with fluconazole on Candida,and to explore a new idea for clinical treatment of candidiasis.MethodsRPMI1640 medium microdilution assay and chessboard microdilution assay were performed to identify the minimal inhibitory concentration(MIC50)and Fractional inhibitory concentrate ionindex(FICI)of the three compounds alone or combined with fluconazole against fluconazole-resistant Candida albicans(6-02)、Candida glabrata(CBS 138)、Candida auris(CBS 12776)、Candida tropicalis(51184)、Candida krusei(ATCC6258)、Candida parapsilosis(ATCC22019),and plot the growth dynamic curve with the microbial growth dynamic monitoring system at the same time.Result1、All the six strains of Candida were resistant to isoliquiritigenin and 18a-glycyrrhetinic acid,while licochalconeA had different degrees of inhibition to all strains.2、When licochalconeA,18α-glycyrrhetinic acid,isoglycyrrhetinic acid were combined with fluconazole seperately,FICI values were all greater than 0.5,indicating that there was no synergistic effect.3、The growth curve of the six Candida strains without drug addition was roughly S-shaped.Except for the little change of the curve of Candida auris after drug addition,the other Candida strains were uniformly slowed and flattened to varying degrees after drug addition.Conclusion1、Licochalcone A has effect on fluconazole-resistant Candida albicans,Candida tropicalis,Candida krusei and Candida parapsilosis in varying degrees;2、Candida auris was resistant to fluconazole and three glycyrrhiza monomer.3、Licochalcone A,18α-glycyrrhetinic acid,isoglycyrrhetinic had no synergistic anti-candida effect on Candida with fluconazole.