酵母菌YH1的分离鉴定及其生长特性研究

Isolation and Identification of Yeast YH1 and Its Growth Characteristics

为了得到一株酿酒酵母,并得到该菌株在一定条件下的生长特性,本试验从葡萄架下的土壤样品中分离纯化出1株菌株YH1,通过形态学及分子生物学对菌株进行了鉴定,并对其进行了遗传稳定性评价。结果表明该菌株为酿酒酵母,且该菌株生物量维持在5.43~5.92 g·500 mL^(-1)之间,具有良好的遗传稳定性。通过测定该菌株在酵母浸出粉胨葡萄糖(YPD)琼脂培养基中不同时间内的氨基酸态氮、pH和总糖的变化曲线以及致死温度,了解了该菌株的生长特性,试验结果表明该菌株在发酵过程中耗糖量主要在前6 h,氮元素的消耗情况要高于含氮化合物的生成情况,pH呈先下降后上升的趋势,整体维持在5.5~6.5期间,菌株数在第18 h后生长趋于平缓。该菌株在加热10 min,温度高于58℃的条件下,少有或未有菌株生长,并得到该菌株在27℃,180 r·min^(-1)的条件下为菌株最适发酵条件。

In order to obtain a strain of Saccharomyces cerevisiae and obtain the growth characteristics of the strain under certain conditions,a strain YH1 was isolated and purified from the soil samples under the grape trellis,and the strain was identified by morphology and molecular biology,and its genetic stability was evaluated.The results showed that the strain was Saccharomyces cerevisiae,and the biomass of the strain was maintained 5.43-5.92 g·500 mL^(-1),and it had good genetic stability.The growth characteristics of this strain were measured by measuring the change curves of amino acid nitrogen,pH,the total sugars and lethal temperature of the strain in yeast leaching peptone glucose(YPD)agar medium at different time.The results showed that the sugar consumption of the strain was mainly in the first 6 h,the consumption of nitrogen was higher than that of nitrogen-containing compounds,and the pH showed a downward trend and then an upward trend,which remained at 5.5-6.5 as a whole,and the number of strains tended to grow flat after 18 h.The strain was heated for 10 min at the temperature higher than 58℃with little growth or no growth,the optimal fermentation conditions of the strain at 27℃and 180 r·min^(-1) were obtained.