McLaughlin Michael R, Brooks John P
USDA, Agricultural Research Service, Waste Management and Forage Research Unit, POB 5367, Mississippi State, MS 39762, USA.
J Environ Qual. 2008 Jan 4;37(1):266-71. doi: 10.2134/jeq2007.0019. Print 2008 Jan-Feb.
A microplate method was developed as a tool to test phages for their ability to control Salmonella in aqueous environments. The method used EPA (U.S. Environmental Protection Agency) worst case water (WCW) in 96-well plates. The WCW provided a consistent and relatively simple defined turbid aqueous matrix, high in total organic carbon (TOC) and total dissolved salts (TDS), to simulate swine lagoon effluent, without the inconvenience of malodor and confounding effects from other biological factors. The WCW was originally defined to simulate high turbidity and organic matter in water for testing point-of-use filtration devices. Use of WCW to simulate lagoon effluent for phage testing is a new and innovative application of this matrix. Control of physical and chemical parameters (TOC, TDS, turbidity, temperature, and pH) allowed precise evaluation of microbiological parameters (Salmonella and phages). In a typical application, wells containing WCW were loaded with Salmonella enterica susp. enterica serovar Typhimurium (ATCC14028) and treated with phages alone and in cocktail combinations. Mean Salmonella inactivation rates (k, where the lower the value, the greater the inactivation) of phage treatments ranged from -0.32 to -1.60 versus -0.004 for Salmonella controls. Mean log(10) reductions (the lower the value, the greater the reduction) of Salmonella phage treatments were -1.60 for phage PR04-1, -2.14 for phage PR37-96, and -2.14 for both phages in a sequential cocktail, versus -0.08 for Salmonella controls. The WCW microcosm system was an effective tool for evaluating the biocontrol potential of Salmonella phages.
开发了一种微孔板方法作为测试噬菌体在水环境中控制沙门氏菌能力的工具。该方法在96孔板中使用美国环境保护局（EPA）的最坏情况水（WCW）。WCW提供了一种一致且相对简单的限定浑浊水基质，总有机碳（TOC）和总溶解盐（TDS）含量高，以模拟猪泻湖废水，避免了恶臭和其他生物因素的混杂影响带来的不便。WCW最初被定义用于模拟水中的高浊度和有机物，以测试使用点过滤装置。将WCW用于模拟泻湖废水进行噬菌体测试是该基质的一种新的创新应用。对物理和化学参数（TOC、TDS、浊度、温度和pH）的控制使得能够精确评估微生物参数（沙门氏菌和噬菌体）。在典型应用中，装有WCW的孔中接种肠炎沙门氏菌悬液。肠炎沙门氏菌鼠伤寒血清型（ATCC14028），并单独用噬菌体以及以鸡尾酒组合形式进行处理。噬菌体处理的沙门氏菌平均失活率（k，值越低，失活程度越高）范围为-0.32至-1.60，而沙门氏菌对照为-0.004。沙门氏菌噬菌体处理的平均对数（10）减少量（值越低，减少量越大），噬菌体PR04-1为-1.60，噬菌体PR37-96为-2.14，顺序鸡尾酒中的两种噬菌体均为-2.14，而沙门氏菌对照为-0.08。WCW微观系统是评估沙门氏菌噬菌体生物防治潜力的有效工具。
