蜂粮中Lactobacillus kunkeei的益生特性研究

蜂粮是植物花粉、蜂蜜和蜜蜂唾液的发酵混合物,是营养丰富的天然食材。作者从蜂粮中分离到61株乳酸杆菌,经16S rRNA基因测序,鉴定为Lactobacillus kunkeei。首先,用邻苯二甲醛法对61株L.kunkeei进行胆固醇去除能力检测,其中5株菌胆固醇去除能力均大于15%,菌株B35对胆固醇的去除率达到(29.07±1.30)%。随后,对这5株L.kunkeei进行酸耐受性、胆盐耐受性、抗生素耐药性及抑菌等益生特性进行研究。耐酸实验和耐胆盐实验结果表明,5株L.kunkeei均具有良好的耐酸性和胆盐耐受性。药敏试验结果表明,5株L.kunkeei对4种临床常用抗生素(红霉素、克林霉素、庆大霉素、万古霉素)均敏感。通过琼脂扩散法抑菌实验,发现5株L.kunkeei对大肠埃希氏菌、金黄色葡萄球菌均有一定的抑菌作用。B35菌株的细胞黏附性能良好,对Caco-2细胞的黏附率达到3.32%。从蜂粮中分离到5株具有良好益生特性的菌株,其中菌株B35的益生特性最佳,为益生菌的开发与利用提供了新的菌种资源。

Probiotic Characteristics of Lactobacillus kunkeei Strains from Bee Bread

Bee bread, a fermented mixture of plant pollen, honey and bee saliva, is a natural and nutritious food. A total of 61 strains of Lactobacillus were isolated from the bee bread and identified as Lactobacillus kunkeei by 16S rRNA gene sequencing. The activity of 61 strains of L. kunkeei to degradate cholesterol was detected by ortho-phthalaldehyde (OPA) method. The degradation rates of 5 strains among them were higher than 15%, and the cholesterol degradation rate of B35 reached (29.07±1.30)%. The 5 L. kunkeei strains were further studied to investigate their probiotic characteristics including acid resistance, bile salt tolerance, antibiotic resistance and bacteriostatic activities. Their acid and bile salt resistance tests showed that 5 strains of L. kunkeei had good acid and bile salt tolerance. The antibiotic susceptibility test results showed that the 5 L. kunkeei strains were sensitive to four clinically significant antibiotics including erythromycin, kanamycin, norfloxacin and vancomycin. The antibacterial activity to gram-positive and gram-negative of 5 L. kunkeei strains was tested by agar diffusion method. All the 5 strains inhibited the growth of Escherichia coli and Staphylococcus aureus. The adhesion rate of strain B35 to Caco-2 cells in vitro was 3.32%. In this study, 5 L. kunkeei strains isolated from bee bread showed good probiotic performance, of which strain B35 had the best probiotic properties. This study offers new bacteria sources for the development and utilization of probiotics.