Antifungal Effect Of Oligochitosaccharides Against Dermatophyte In Vitro And In Vivo

The natural oligochitosaccharides has broad-spectrum antimicrobial activity. There are non-toxic to humans and animals. The article uses the method of enzymatic degradation couple with membrane to separate oligochitosaccharides. The rate of inhibition of the dermatophyte treated with oligochitosaccharides was determinated and preliminary study its inhibitory mechanism.The main resuLts are as follows:1.The membrane separation was used to produce oligochitosaccharides, the mainly physical and chemical indicators of products:number average molecular weight is1760.86; degree of deacetylation is91.08%; ash is0.589%.2. The minimum inhibitory concentration of dermatophyte treated with oligochitosaccharides measured by the method of M38-A2. The minimum inhibitory concentration was2.5mg/mL. MTT assays was used to determine the germination of spores. Compared with the control group, the activity of spore germination in the oligochitosaccharides treated group at the dose of1mg/mL has been highly significant difference (p<0.01).3.The inhibitory effect of oligochitosaccharides on the mycelial growth was measured. Cultured to11d, treated with10mg/mL oligochitosaccharides, it can inhabit T. rubrum10-098251.10%growth rate.4In the liquid culture conditions, oligochitosaccharides inhibit dermatophyte biomass was measured. After72h,1mg/mL oligochitosaccharides mixed with culture,biomass is no significant difference with the control group, with5mg/mL,10mg/mL has a difference (p<0.05).5. In the liquid culture conditions, oligochitosaccharides inhibit dermatophyte nitrogen conversion was measured. After72h, compared with the control group, mycelial nitrogen treated with the dose of10mg/mL oligochitosaccharides group was no significant difference, and with20mg/mL,30mg/mL oligochitosaccharides group has a significant difference (p<0.01).6. Using a scanning electron microscope to observe the dermatophyte cells morphology, results show that after3d, the1%oligochitosaccharides mixed SDA liquid medium change the external shape and internal structure of the T. rubrum10-0982cells.7. By constructing guinea pig dermatophyte model in vivo assays. After15days, Compared with the control group, the lesion score of1%oligochitosaccharides treated group has significant difference (p<0.05),5%oligochitosaccharides treated group and group lesion score difference was statistically significant (p<0.01),0.1%oligochitosaccharides has no statistically significant.