Mustafa Amina, Nawaz Muhammad, Rabbani Masood, Tayyab Muhammad, Khan Madiha
Institute of Microbiology, University of Veterinary and Animal Sciences, Lahore, 54000, Punjab, Pakistan.
Research School of Biology, Australian National University, Canberra, 2601, ACT, Australia.
Open Life Sci. 2022 Aug 17;17(1):978-990. doi: 10.1515/biol-2022-0100. eCollection 2022.
Lactobacilli ( = 24), isolated from human infants and yogurt, showed variable activity against (8.0 ± 1.0 to 16.6 ± 0.5 mm) and other gut pathogens (9.0 ± 1.0 to 15.3 ± 0.5 mm), as determined by a well diffusion assay. The isolates were identified as (FY1, FY3, FY4, IL2, and IL5), (FY6 and FY7), sp. (IL7), and (IL12). All isolates showed variable tolerance to acidic pH for 3 h and visible growth at pH 4 and in the presence of 0.3% ox-bile. The antibiotic susceptibility profile of isolates indicated resistance against vancomycin, ciprofloxacin, streptomycin, and lincomycin. Isolates had variable auto-aggregation and showed variable capabilities to co-aggregate with . Based on all tested parameters, IL2, IL5, and IL12 were selected for co-culture experiments, followed by evaluation in Balb/c mice. All the selected isolates resulted in a 100% reduction in in broth. isolates efficiently colonized mouse guts and inhibited colonization. Overall, there was ≥99.06% and ≤4.32 Mean log reduction in counts in mice feces within 7 days. The study, thus, provided characterized lactobacilli that could be considered as potential ingredients for probiotic formulations intended to prevent infection in humans.
从人类婴儿和酸奶中分离出的24株乳酸杆菌，通过打孔扩散法测定，其对（抑菌圈直径为8.0±1.0至16.6±0.5毫米）和其他肠道病原体（抑菌圈直径为9.0±1.0至15.3±0.5毫米）表现出不同的活性。这些分离株被鉴定为嗜酸乳杆菌（FY1、FY3、FY4、IL2和IL5）、干酪乳杆菌（FY6和FY7）、植物乳杆菌（IL7）和卷曲乳杆菌（IL12）。所有分离株在酸性pH条件下3小时均表现出不同的耐受性，在pH 4以及存在0.3%牛胆汁的情况下可见生长。乳酸杆菌分离株的抗生素敏感性谱显示对万古霉素、环丙沙星、链霉素和林可霉素耐药。分离株具有不同的自聚集能力，并且与大肠杆菌共聚集的能力也各不相同。基于所有测试参数，选择嗜酸乳杆菌IL2、嗜酸乳杆菌IL5和卷曲乳杆菌IL12进行共培养实验，随后在Balb/c小鼠中进行评估。所有选定的分离株在肉汤中均使大肠杆菌数量减少100%。乳酸杆菌分离株有效地定殖于小鼠肠道并抑制大肠杆菌定殖。总体而言，7天内小鼠粪便中大肠杆菌数量的平均对数减少≥99.06%且≤4.32。因此，该研究提供了具有特征的乳酸杆菌，可被视为用于预防人类大肠杆菌感染的益生菌制剂的潜在成分。
