不同浓度半胱胺对嗜热链球菌体外培养的影响

Impact of different concentrations of cysteamine on Streptococcus thermophilus culture in vitro

用含有不同浓度半胱胺的肉汤培养基体外培养嗜热链球菌,每小时测定其OD值(550nm),绘制曲线,观察对嗜热链球菌活性的影响。结果表明,半胱胺的浓度为3.2mg·mL-1时,抑制率为11.72%(P<0.05);半胱胺的浓度为5.0mg·mL-1时,抑制率为17.15%(P<0.01);半胱胺的浓度为0.05mg·mL-1时,促进率为9.66%(P<0.05);半胱胺的浓度为0.1、0.2、0.4、0.5、0.8、1.6mg·mL-1时,差异不显著(P<0.05)。

The broth medium containing different concentrations of cysteamine was used to culture Streptococcus thermophilus. The OD（550 nm） value was measured every hour to draw the growth curve and statistical analysis was carried out. The activity of Streptococcus thermophilus was observed. The results showed that an 11.72% of inhibition rate（P〈0.05） was achieved when the concentration of cysteamine was 3.2 mg·mL^-1; 17.15% of inhibition rate（P〈0.01） was achieved when the concentration of cysteamine was 5.0 mg·mL^-1. However, 9.66% （P〈 0.05） of promotion was achieved when the concentration of cysteamine was 0.05 mg·mL^-1. There was no significant difference （P 〉0.05） when the concentrations of cysteamine were 0.1, 0.2, 0.4, 0.5, 0.8 and 1.6 mg·mL^-1, respectively.