The Stress Resistance and Antibacterial Ability of 4 Kinds of Potential Engineering Yeasts to Pathogenic Canidia albicans YTS-03

In order to obtain an engineered killer yeast which was highly resistant to the fungal pathogen Canidia albicans YTS-03,and to develop antifungal preparations,four kinds of excellent strains for resistance of high temperature,acid and alkali,salt,antibiotic,and antibacterial ability were tested. The results showed that the strain PA1,SY3-1A,DD21-2 and WM1 had wide adaptability to temperature and environmental pH,which could grow under the conditions of 12~37℃ and pH3~9. The salt tolerances of the strains were quite different,9%(PA1),8%(SY3-1A),7%(DD21-2),and 4%(WM1)respectively. The temperature,environmental pH,and salt concentration all had significant effects on the growth of strains(P<0.05).The killer yeasts were more sensitive to antibiotics,having resistance to itraconazole and mycin with low concentration(5 μg/mL)or chloroconazole,and different killer yeast strains had different drug resistance characteristics. These four test strains could kill Candida albicans,Metschnikowiabicuspidata and Candida tropicalis,and with strong killing activity,the diameter of inhibition zone of strain PA1、SY3-1A、DD21-2、WM1 against C. albicans YTS-03 reached 23.0,14.1,22.3 and 21.5 mm,respectively.