Research Department of Plant Biology and Biotechnology, Loyola College, Nungambakkam, Chennai 600034, Tamil Nadu, India.
Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, Toluca, Mexico.
Microb Pathog. 2018 May;118:126-132. doi: 10.1016/j.micpath.2018.03.022. Epub 2018 Mar 14.
The desideratum aim of the present context was to isolate a promising antagonist probiotic bacterium from fermented food item as biocontrol agent against uropathogens. Among diversified isolates evaluated for antagonistic trait, Staphylococcus succinus strain AAS2 was found to be an auspicious candidate against urinary tract infection (UTI) causing bacterial pathogens, being the most active against Staphylococcus aureus with substantial activity of 352.5 ± 5.4 AU/mL. Further, the in vitro probiotic attributes of strain AAS2 were assessed using systematic methodology. The isolate exhibited tolerance to acidic condition (up to pH 3.0) and simulated gastric juice (at pH 3.0) with fairly high survival logarithmic cell counts of 5.3 ± 0.15 and 5.23 ± 0.02 log cfu/mL, respectively. Additionally, strain AAS2 showed capability to resist 0.5% w/v bile salt too. It also revealed significant values of auto-aggregation (32.5 ± 1.3-56.5 ± 1.4%) and cell surface hydrophobicity (38.35 ± 1.4%) properties. The isolate showed resistivity towards phenol (6.8 ± 0.08 log cfu/mL) and lysozyme (58.6 ± 1.6%). Further, the susceptibility trait of strain AAS2 to conventional antibiotics made this isolate a promising probiotic bacterium. Most importantly, the isolate depicted DPPH (2,2-Diphenyl-1-picrylhydrazyl) and hydroxyl radical scavenging activities in a concentration dependent manner, thereby exhibiting its propitious antioxidative properties. In a nutshell, the outcomes of this investigation divulge the plausible use of S. succinus strain AAS2 as biocontrol agent against uropathogens, and recommended further applications in pharmaceutics due to its pronounced probiotic traits.
本研究旨在从发酵食品中分离出一种有前途的拮抗益生菌作为抗尿路病原体的生物防治剂。在评估的多种分离物中，发现金黄色葡萄球菌菌株 AAS2 对引起尿路感染（UTI）的细菌病原体具有良好的候选作用，对金黄色葡萄球菌的活性最高，活性为 352.5±5.4 AU/mL。此外，还使用系统方法评估了菌株 AAS2 的体外益生菌特性。该分离物对酸性条件（高达 pH 3.0）和模拟胃液（在 pH 3.0 时）具有耐受性，存活率对数细胞计数分别为 5.3±0.15 和 5.23±0.02 log cfu/mL。此外，菌株 AAS2 还能抵抗 0.5%w/v 胆汁盐。它还显示出显著的自聚集（32.5±1.3-56.5±1.4%）和细胞表面疏水性（38.35±1.4%）特性值。该分离物对苯酚（6.8±0.08 log cfu/mL）和溶菌酶（58.6±1.6%）具有抗性。此外，菌株 AAS2 对常规抗生素的敏感性使该分离物成为一种有前途的益生菌。最重要的是，该分离物以浓度依赖的方式显示出 DPPH（2,2-二苯基-1-苦基肼基）和羟基自由基清除活性，从而表现出其有利的抗氧化特性。总之，本研究的结果表明，金黄色葡萄球菌 AAS2 菌株可作为抗尿路病原体的生物防治剂，由于其显著的益生菌特性，建议在制药领域进一步应用。
