Effect Of Boric Acid On Microecological Flora Of Mouse Skin Infected With Candida Albicans

Objective:To explore the therapeutic effect of 3%boric acid on skin infection of Candida albicans in mice and the effect of skin microflora.Methods:ICR female mice were randomly divided into blank group,model group,and boric acid group(n=12).Candida albicans mycelium suspension 1.5×10~9CFU/m L,0.1 m L was intradermically injected into the back injection site of mice,and the blank group was treated with sterilized injection water(SWFI).A mouse model of skin Candida albicans infection was constructed.The clinical manifestations,fungal fluorescence microscopy and colony count were observed.After successful modeling,the mice in the boric acid group were wet with 3%boric acid for 30 minutes(once every 12 hours).The model group was treated with SWFI,while the blank group was not treated.One week after treatment,the treatment of each group was observed with naked eyes,and skin samples were collected.DNA was extracted for high-throughput sequencing of ITS and 16S rRNA genes to detect the effect of boric acid on skin microflora.Results:(1)the characteristic clinical manifestations of skin infection such as white membrane,erosion and ulcer appeared in the model of mice.Spores and clumps of hyphae were found in fungal fluorescence microscopy.Candida albicans showed smooth emerald green colonies on the chromogenic medium,and the count reached 1.0×10~5-1.0×10~6CFU/g.(2)After one week of treatment,there was no obvious change in the model group,but the degree of skin injury was alleviated,the wound healed obviously and the exudation decreased in the boric acid group.(3)The results of ITS showed that the abundance of Candida albicans in boric acid group was significantly lower than that in model group(P<0.01).(4)The results of 16S rRNA showed that compared with the blank group,the microbial richness of the model group and boric acid group increased,the diversity of the model group increased,but the diversity of the boric acid group had no significant change.Compared with the model group,the microbial richness of the boric acid group changed little,but the diversity decreased.There was significant difference between boric acid group and model rental group,but similar to the blank group.In boric acid group,the abundance of Proteobacteria,Enterobacteriaceae and Escherichia-Shigella,increased significantly(P<0.01)and the abundance of Firmicutes,Staphylococcaceae and Staphylococcus decreased significantly(P<0.01).Conclusion:(1)The skin infection model of Candida albicans can be established by intradermically injection of 1.5×10~9CFU/m L Candida albicans mycelium suspension 0.1m L into the injection site on the back of mice.(2)3%Boric acid significantly reduces skin infection symptoms with Candida albicans and inhibit its growth.(3)3%Boric acid reduces the diversity of skin microorganisms,but has little effect on richness.Increases the abundance of Proteobacteria,Enterobacteriaceae and Escherichia-Shigella,and decreases the abundance of Firmicutes,Staphylococcaceae and Staphylococcus,which may have protective effects and achieve dynamic balance.