In Vitro Antibacterial Study Of The Extract Of JINGUANLAN Formula On Acne Vulgaris-related Pathogenic Bacteria

Objective: The Chinese medicine “JINGUANLAN” formula is a protocol independently developed by the Pharmacy Department of our hospital.It has the functions of cooling blood,clearing heat,and detoxification.It can be used for internal use to treat exuberant blood heat,and external use can be used to treat sores.In this thesis,in vitro experiments were carried out to determine whether the formula had effect on the growth of the three main pathogenic bacteria（Propionibacterium acnes,Staphylococcus aureus,Staphylococcus epidermidis）and its bacteriostatic effect.Provide experimental basis for clinical treatment of acne vulgaris.Method: According to the formula of the “JINGUANLAN” formula preparation（The weight fraction ratio of honeysuckle,Radix isatidis,Guanzhong,licorice,and astragalus is 1:1:1:1:3）,the medicine was weighed,and its active components were extracted by decoction,and the crude drug concentration was 1 g/m L,and then the powder was prepared by alcohol precipitation and drying,and use sterile distilled water to prepare the maximum drug concentration（500 mg/m L）.Firstly,the diameter of the inhibition zone of the three drug concentrations（500 mg/m L,250 mg/m L,100 mg/m L）of extract of JINGUANLAN formula on the three main pathogenic bacteria of vulgaris acne was determined by the agar punching method,to determine whether it has an effect on the growth of the three main pathogenic bacteria of vulgaris acne;furthermore,the minimum inhibitory concentration（MIC）and the minimum bactericidal concentration（MBC）of the three main pathogenic bacteria of extract of JINGUANLAN formula were determined by the broth microdilution method.The bacterial growth curve is evaluating the effect of extract of JINGUANLAN formula on three main pathogenic bacteria of vulgaris acne.Results: 1.Agar punching method: the diameters of the inhibition zone of 500mg/m L extract of JINGUANLAN formula against P.acnes,S.epidermidis and S.aureus were respectively（27.67 ± 2.52）mm,（23.33 ± 1.53）mm,（22.00 ± 1.00）mm;the diameters of the inhibition zones of 250 mg/m L extract of JINGUANLAN formula against P.acnes,S.epidermidis and S.aureus were respectively（22.33 ± 0.58）mm,（20.67 ± 1.53）mm,（20.11 ± 1.2）mm;the diameters of the inhibition zones of 100mg/m L extract of JINGUANLAN formula against P.acnes,S.epidermidis and S.aureus were respectively（13.30 ± 0.75）mm,（10.67 ± 1.53）mm,（10.67 ± 0.58）mm.The diameter of the inhibition zone of the three groups of experiments was related to the concentration of the extract of JINGUANLAN formula（r = 0.953,p < 0.001）.2.Broth micro-dilution method: The MIC of extract of JINGUANLAN formula against P.acnes,S.epidermidis,and S.aureus were 25 mg/m L,25 mg/m L,and 25mg/m L,respectively;MBC was 25 mg/m L,50 mg/m L,25 mg/m L,respectively.The MIC of positive control erythromycin against P.acnes,S.epidermidis,and S.aureus were 0.125 μg/m L,0.125 μg/m L,0.25 μg/m L,respectively;MBC were 0.25 μg/m L,0.25 μg/m L,0.5 μg/m L,respectively.In the positive control group,the MIC of clindamycin against P.acnes,S.epidermidis,and S.aureus were 0.031 μg/m L,0.063μg/m L,0.063 μg/m L,respectively;MBC were 0.063 μg/m L,0.125 μg/m L,0.125μg/m L,respectively;the MIC of positive control fusidic acid against P.acnes,S.epidermidis,and S.aureus were 0.625 μg/m L,5 μg/m L,5 μg/m L,respectively;MBC was 2.5 μg/m L,10 μg/m L,10 μg/m L,respectively.3.Bacterial growth curve: The extracts of JINGUANLAN formula have inhibitory effect on the growth of the three pathogenic bacteria of acne vulgaris,mainly affecting the delay period of the bacteria,and the bacteriostatic effect is more obvious with the increase of the concentration of the extract of JINGUANLAN formula.Conclusion: The extract of JINGUANLAN formula has a certain inhibitory effect on the growth of three pathogenic bacteria（P.acnes,S.epidermidis,and S.aureus）of acne vulgaris infection in vitro.In this study,it is the first time that the antibacterial experiment proves that the extract of JINGUANLAN formula inhibits the growth of acne vulgaris pathogenic bacteria,and the antibacterial effect of the compound preparation is proved in vitro.Lay the foundation for the study of the mechanism of action.