胡萝卜浓缩汁中耐热菌的分离及特性研究

对胀袋胡萝卜浓缩汁中的耐热菌进行了分离,通过形态观察和ITS rDNA基因序列分析方法鉴定耐热菌,通过碳源利用试验考查菌株的部分生理生化特性,通过热和酸碱处理考察菌株的热稳定性和酸碱稳定性,利用超声波破壁技术考察细胞中多糖、还原糖和色素情况。结果表明:胀袋胡萝卜浓缩汁中分离得到一株耐热菌SR-1,经形态学和分子生物学技术鉴定为肉色掷孢酵母,该菌经80℃热处理5~30min,生长良好;经90℃热处理15 min仍能生长,处理20 min后不能生长;在pH 6.0~8.0环境中生长良好,pH 3.0以下不能生长。超声波破壁后上清液还原糖含量为6.02~7.86mg/mL,多糖含量为32.93~41.78 mg/mL,菌体色素在414,539,634nm处有吸收峰。

Screening and characteristics of heat-resistant strain from concentrated carrot juice

The heat-resistant strain was isolated and identified by morphological features and ITS rDNA gene sequence analysis.Some physiological and biochemical characteristics of the strain were examined by carbon source utilization experiment.The thermal stability and acid-base stability of the strain were examined by heat and acid-base treatment.With the ultrasonic technology,the polysaccharides,reducing sugar and pigment in cells were examined.The results indicated that the strain SR-1 belongs to Sporobolomyces carnicolor.It was heat-resistant,and grew stably after heat treatment at 80℃for 5~30 min,and at 90 ℃for 15 min.However,it couldn’t grow after treated at 90 ℃for20 min.The strain could grow well at pH 6.0~8.0,but could survive under pH 3.0.Hydrochloric acid with 200,400,600 and800 Wultrasound were used to break the cell wall,the supernatant contained 6.02~7.86 mg/mL of reducing sugar,32.93~41.78 mg/mL of polysaccharide,and the absorption peaks of mycelium pigments were found at waves of 414,539 and 634 nm.