This study aimed to screen chicken-derived Bacillus strains suitable for fermentation of Pseudostellaria heterophylla fibrous roots.Bacillus strains were isolated from cecal chyme samples of healthy chicken and fermen...This study aimed to screen chicken-derived Bacillus strains suitable for fermentation of Pseudostellaria heterophylla fibrous roots.Bacillus strains were isolated from cecal chyme samples of healthy chicken and fermented with P.heterophylla fibrous roots for re-screening.Biological characterization,safety evaluation,and identification based on morphological characteristics,physiological and biochemical properties,and molecular biological identification were carried out for the strains screened out.The results showed that five Bacillus strains X1-X5 were isolated from the cecal chyme samples in primary screening,and two elite strains X1 and X4 were obtained by re-screening.Both strains X1 and X4 had the ability to produce amylase and protease,adapt to pH value of 6-8,and tolerate bile salt of 0.1%-0.3%and simulated gastric and intestinal fluid environments.The safety evaluation results showed that the strains had no hemolytic activity,which indicated good biological safety.Strains X1 and X4 were identified as Bacillus subtilis and Bacillus licheniformis,respectively,based on the morphological characteristics,physiological and biochemical properties,and molecular biological identification.In summary,strains X1 and X4 with strong stress resistance,probiotic properties,and safety can be used as candidate probiotic strains for the fermentation of P.heterophylla fibrous roots.展开更多
文摘This study aimed to screen chicken-derived Bacillus strains suitable for fermentation of Pseudostellaria heterophylla fibrous roots.Bacillus strains were isolated from cecal chyme samples of healthy chicken and fermented with P.heterophylla fibrous roots for re-screening.Biological characterization,safety evaluation,and identification based on morphological characteristics,physiological and biochemical properties,and molecular biological identification were carried out for the strains screened out.The results showed that five Bacillus strains X1-X5 were isolated from the cecal chyme samples in primary screening,and two elite strains X1 and X4 were obtained by re-screening.Both strains X1 and X4 had the ability to produce amylase and protease,adapt to pH value of 6-8,and tolerate bile salt of 0.1%-0.3%and simulated gastric and intestinal fluid environments.The safety evaluation results showed that the strains had no hemolytic activity,which indicated good biological safety.Strains X1 and X4 were identified as Bacillus subtilis and Bacillus licheniformis,respectively,based on the morphological characteristics,physiological and biochemical properties,and molecular biological identification.In summary,strains X1 and X4 with strong stress resistance,probiotic properties,and safety can be used as candidate probiotic strains for the fermentation of P.heterophylla fibrous roots.
