温度及pH条件对乳酸菌生长影响的研究

Effects of Different Temperatures and pH on the Growth of Lactic Acid Bacteria

以MRS琼脂培养基和BCP培养基为载体,通过目测菌液浑浊度及生长状态,测定菌液OD600值和培养终点时的pH值,对从乳制品中分离出的乳酸菌的生长温度及pH值进行了研究.结果表明,在不加缓冲液的培养基中,在pH为6.5～8.5、38℃培养时,所有菌株生长良好.当环境条件超出这一范围时,乳酸菌生长受到抑制.从OD600值可以看出,实验分离到的10株菌最适pH都在6.5左右,最适生长温度在38℃左右,但pH值与温度的范围在各菌株间略有差异.

This experiment is designed to analyze the effects of different temperatures and pH on lactobacillus isolated from milk by improved MRS culture and BCP culture. The OD600, pH and vaccine opacity of the culture at terminal were measured. The results of this experiment are summarized as follows： the lactobacillus can massively grow in 38℃ and pH 6.5-8.5 in non-buffer culture, produce the lactic acid and lower the acidity of the environment. The lactobacillus growth is inhibited beyond the range. The pH 6.5 and 38℃ are the most suitable condition to these 10 strains, but every strain performs different scope.