Department of Dairy Science, Faculty of Agriculture, Cairo University, Giza, Egypt.
Department of Microbiology, Faculty of Agriculture, Cairo University, Giza, Egypt.
FEMS Microbiol Lett. 2021 Apr 22;368(6). doi: 10.1093/femsle/fnab030.
The study aimed to evaluate the probiotic and safety properties of lactic acid bacterial (LAB) strains isolated from the gut microbiota of honey bee Apis mellifera L., since this source remains a promising reservoir of microbial diversity. A total of five bacterial isolates were molecularly identified using 16S rRNA gene sequencing as Enterococcus faecalis-HBE1, Lactobacillus brevis-HBE2, Enterococcus faecalis-HBE3, Enterococcus faecalis-HBE4 and Lactobacillus casei-HBE5. Gut tolerance conditions (low pH and bile salt) were evaluated. Exopolysaccharides (EPS) production, hemolytic, antioxidant activity, resistance toward antibiotics and technological characteristics (starter activity, pH and proteolysis) were examined. The five isolates showed a high survival rate (>95%), under gastrointestinal tract conditions indicating excellent potential for application as probiotics. The isolates showed no hemolytic activities and good acidification rates in the range of pH 4.6-4.98 after incubation at 37°C for 24h. The isolates exhibited promising proteolytic activity as well as DPPH radical scavenging activity in the range of 16.52-59.39%. All the tested isolates had the capability to produce exopolysaccharides except Lactobacillus casei-HBE5. These results put forward that lactic acid bacterial strain isolated from honey bee workers can be considered as promising candidates for future applications as starter cultures and could constitute new potential probiotics for the production of functional dietary products promoting health benefits.
本研究旨在评估从蜜蜂肠道微生物群中分离出的乳酸菌（LAB）菌株的益生菌和安全性特性，因为这种来源仍然是微生物多样性的有前途的蕴藏库。使用 16S rRNA 基因测序对总共 5 个细菌分离株进行了分子鉴定，分别为粪肠球菌-HBE1、短乳杆菌-HBE2、粪肠球菌-HBE3、粪肠球菌-HBE4 和干酪乳杆菌-HBE5。评估了肠道耐受条件（低 pH 值和胆汁盐）。考察了胞外多糖（EPS）的生产、溶血、抗氧化活性、抗生素抗性和技术特性（起始活性、pH 值和蛋白水解）。五种分离株在胃肠道条件下具有高存活率（>95%），表明其作为益生菌具有优异的应用潜力。分离株无溶血活性，在 37°C 孵育 24 小时后，pH 值为 4.6-4.98 时具有良好的酸化率。分离株具有有希望的蛋白水解活性和 DPPH 自由基清除活性，范围分别为 16.52-59.39%。除干酪乳杆菌-HBE5 外，所有测试的分离株都能够产生胞外多糖。这些结果表明，从蜜蜂工蜂中分离出的乳酸菌菌株可被视为未来作为发酵剂应用的有前途的候选菌株，并且可以构成生产促进健康益处的功能性膳食产品的新的潜在益生菌。
