Functional probiotics of lactic acid bacteria from Hu sheep milk
Functional probiotics of lactic acid bacteria from Hu sheep milk
复制标题
湖羊乳乳酸菌功能性益生菌
DOI：
10.1186/s12866-020-01920-6
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发表时间：
2020-07-28
期刊：
影响因子：
4.2
通讯作者：
Yin, Yulong
中科院分区：
文献类型：
--
作者：
Chen, Taohong;Wang, Leli;Yin, Yulong
研究背景益生菌是与人类健康密切相关的重要微生物。湖羊是我国重要的绵羊品种之一。湖羊羊奶具有营养价值高、低过敏性等特点。特别是，这种牛奶含有大量的牛奶益生元和益生菌。结果通过16 S rRNA序列分析，从湖羊乳中筛选出40株具有益生活性的菌株，并对其抗菌活性进行了评价。大肠埃希菌（ETEC）和豚鼠气单胞菌（Aeromonascacetylum）。这些分离菌株中有4株表现出有效的抑菌能力和潜在的健康特性。我们还检查了这些候选细菌的安全性，包括三种乳酸乳球菌菌株并通过体外抑菌活性、细胞表面特性等方面的研究，对该菌株进行了初步评价（疏水性、共聚集和自聚集）、热处理、抗生素敏感性、胃肠道中的模拟转运耐受性，和酸/胆汁耐受性。所获得的结果显示，HSM-1、HSM-10、HSM-14和HSM-18在不同条件下（例如低pH、牛胆汁的存在下）显示出高存活率，并显示出高疏水性。此外，HSM-14在胃肠道耐受性、对病原菌的抗菌活性等方面均优于其他菌株，且这些结果明显优于其他候选菌。结论湖羊乳作为潜在乳酸菌（LAB）益生菌的探索来源，开辟了非常规乳源益生菌使用的新视野。所选的乳酸菌菌株是优良的益生菌候选者，可用于未来的畜牧业。研究的基本原理是利用湖羊乳作为潜在益生菌LAB的来源。本研究为进一步探索湖羊乳微生物区系建立完整的细菌资源库奠定了基础。
BackgroundProbiotics are being considered as valuable microorganisms related to human health. Hu sheep is referred as one of the important sheep breeds in China. Goat milk produced by Hu sheep is characterized with high nutritional value and hypoallergenic in nature. Particularly, this milk contains plenty of milk prebiotic and probiotic bacteria. This study was aimed to scrutinize more bacterial strains from Hu sheep milk with potential probiotic activity.ResultsBased on 16S rRNA sequence analysis, pool of forty bacterial strains were identified and evaluated their antimicrobial activities againstStaphylococcus aureus, enterohemorrhagicEscherichia coli(EHEC),Salmonella typhimurium,Listeria monocytogenesenterotoxigenicE. coli(ETEC) andAeromonas caviae. Four out of these isolated strains demonstrated their efficient bacteriostatic ability and potential healthy properties. We also examined the safety aspects of these bacterial candidates including threeLactococcus lactisstrains (named as HSM-1, HSM-10, and HSM-18) and oneLeuconostoc lactisstrain (HSM-14), and were further evaluated via in vitro tests, including antimicrobial activity, cell surface characteristics (hydrophobicity, co-aggregation, and self-aggregation), heat treatment, antibiotic susceptibility, simulated transport tolerance in the gastrointestinal tract, and acid/bile tolerance. The obtained results revealed that HSM-1, HSM-10, HSM-14, and HSM-18 showed high survival rate at different conditions for example low pH, presence of bovine bile and demonstrated high hydrophobicity. Moreover, HSM-14 had an advantage over other strains in terms of gastrointestinal tract tolerance, antimicrobial activities against pathogens, and these results were significantly better than other bacterial candidates.ConclusionHu sheep milk as a source of exploration of potential lactic acid bacteria (LAB) probiotics open the new horizon of probiotics usage from unconventional milk sources. The selected LAB strains are excellent probiotic candidates which can be used for animal husbandry in the future. Rationale of the study was to utilize Hu sheep milk as a source of potential probiotic LABs. The study has contributed to the establishment of a complete bacterial resource pool by exploring the Hu sheep milk microflora.