椰果表面混菌生物膜培养条件优化

Optimization of culture condition of mixed-species biofilm on coconut

为了探明椰果表面混菌生物膜的最优培养条件,采用单因素和正交实验法对保加利亚乳杆菌(Lactobacillus bulgaricus)和嗜热链球菌(Streptococcus thermophilus)在椰果表面形成的混菌生物膜的培养条件进行优化。分别选取培养时间、培养温度、固液比、接种量四个因素。研究结果表明,四个因素对椰果表面形成的混菌生物膜上活菌数的影响效果为:培养温度>培养时间>固液比>接种量。椰果表面混菌生物膜培养条件的优化结果为:培养时间2.5d,培养温度为37℃,椰果与MRS液体培养基组成比例为1∶30(g/mL),接种量为2%。在此培养条件下培养的混菌生物膜,其活菌数达到最大值,为5.79×108CFU/cm2。

In order to explore the optimized culture condition of mixed-species biofilm on coconut, the culture of mixed-species biofilm on coconut formed by Lactobacillus bulgaricus and Streptococcus thermophilus was optimized by single factor and orthogonal test. Four factors （time, temperature, solid- liquid ratio, inoculation amount） were chosen.Results showed the effect of these factors on the viable count of mixed-species biofilm on coconut：temperature 〉 time 〉 solid-liquid ratio 〉 inoculation amount.The optimized culture condition of mixedspecies biofilm on coconut was ;time 2.5d ,temperature 37℃,solid-liquid ratio 1：30（ g/mL）, inoculation amount 2%. Under such condition, the viable count of mixed- species biofilm on coconut reached the maximum of 5.79 × 10^ 8 CFU/cm2.