Cotton Bixie Water Extracts Experimental Studies Of Antibacterial Activity

Research Objective:This research uses herbal extracts and in vitro susceptibility testing to observe in vitro antibacterial activity of Dioscorea septemloba’s water extracts against common bacterias on the surface of eczema lesions (Malassezia and Staphylococcus aureus) and Candida albicans, to explore antibacterial effect of Dioscorea septemloba’s water extracts against common bacterias and fungi in Dermatology area.Research Methods:Extract the Dioscorea septemloba meal with distilled water to obtain Dioscorea septemloba’s water extracts powder, make it to maximum drug concentration (1g/ml) with sterile distilled water. Using the Oxford Cup Method, set1g/ml、500mg/ml、250mg/ml Dioscorea septemloba’s water extracts and sterile distilled water. Apply medicine based agar dilution method to dilute Dioscorea septemloba’s water extracts powder to200mg/ml,160mg/ml,120mg/ml,80mg/ml and40mg/ml five kinds of concentrations, set positive control (containing a culture medium and the bacteria, medicine-free) and negative control (containing a culture medium, medicine and the bacteria free). Set group by bacteria category, each group has seven test tubes. After the inoculation, Staphylococcus aureus and Candida albicans group were put into37℃incubator for24-48hours to observe colony growth in the seven tubes and put Malassezia furfur group into32℃incubator for5-7 days to observed colony growth in the seven test-tubes. After sufficient culture, Oxford cup method using a vernier caliper measurement of the inhibition zone diameter d (mm); using medicine based agar dilution method to observe the growth of the colonies in the tubes.Results:1, Oxford Cup method:Staphylococcus aureus is moderately sensitive to lg/ml and500mg/ml dioscorea septemloba’s water extracts. The inhibition zones are11.2mm,10.5mm. Lightly sensitive to250mg/ml of dioscorea septemloba’s water extracts. Its inhibition zone is9.8mm. Malassezia furfur is moderately sensitive to lg/ml dioscorea septemloba’s water extracts. Its inhibition zone is10.5mm; for500mg/ml and250mg/ml, lightly sensitive to dioscorea septemloba’s water extracts. The inhibition zones are9.9mm and9.2mm. For Candida albicans, to lg/ml,500mg/ml250mg/ml, all show lightly sensitive. The inhibition zones are9mm,8mm and8mm. Sterile distilled water is applied as negative control.2, Medicine based agar dilution method:Dioscorea septemloba’s water extracts’MIC to Staphylococcus aureus is80mg/ml; to Malassezia furfur group is200mg/ml; no obvious effects on Candida albicans. Conclusion:It was found that the Dioscorea septemloba’s water extracts have antibacterial action on Staphylococcus aureus, Malassezia furfur and Candida albicans these three bacterias. In which, Dioscorea septemloba’s water extracts have stronger antibacterial action on Staphylococcus aureus and weaker antibacterial action on Malassezia furfur, and few effects on Candida albicans as well.