烟曲霉在不同温度和营养条件下的生长特性初探

Analysis of the growth characteristics of Aspergillus fumigatus in different temperature and nutrient media

目的确定烟曲霉的最适生长温度、最高生长温度及致死温度。方法生长曲线法用来确定培养烟曲霉的最适宜培养基,并测定其最适生长温度和最高生长温度;菌落计数法用来确定其致死温度。结果 1)酵母浸膏培养基(yeast ex-tract medium,YG)是测定烟曲霉生长曲线的最适宜培养基;2)在YG培养基中,37℃是烟曲霉的最适宜生长温度,52℃为其最高生长温度。随着温度的升高,菌株的生长速度逐渐减慢;3)65℃处理180 min或70℃处理120 min能使烟曲霉完全失活。结论在YG培养基中,37℃是烟曲霉的最适宜生长温度,52℃为其最高生长温度;烟曲霉的致死条件为65℃处理180min或70℃处理120 min。

Objective To determine the growth characteristics of Aspergillus fumigatus in different nutrient media and tempera- ture. Methods .Growth curves were used to determine the optimum medium, optimum and maximum growth temperatures for two strains of Aspergillus fumigatus ：colony counts were used to determine the fatal temperatures for them. Results Three different nu- trient media, yeast extract medium （YG）, minimal medium （MM） and yeast nitrogen base （YNB） , were tested. YG medium was the optimum medium for measuring the growth curves ofAspergillus fumigatus ; In YG medium, the optimum growth temperature for Aspergillusfumigatus was 37℃, and the maximum growth temperature was 52℃. The slower growth rates of strains were observed with gradually elevated temperature. Unexpectedly, the responses of these two strains to high temperature were different：one strain~ growth became slower markedly at 48℃ than at 37℃ during log phase, while the other one grew at 48℃ as well as at 37~C during log phase. The strains of Aspergillusfumigatus were dead when exposed to 65℃ lasting more than 180 min or 70℃ lasting more than 120 rain. Conclusions The optimum and the maximum growth temperature forAspergillusfumigatus were 37℃ and 52℃, respec- tively. The fatal condition for Aspergillus fumigatus was 65℃ lasting more than 180 min or 70℃ lasting more than 120 min.