Escherichia coli has been enlisted as a pathogen of antimicrobial resistance (AMR) importance posing a threat to human health. In the wake of the widespread AMR, lytic bacteriophages remain a promising alternative to antibiotics for controlling the multidrug-resistant (MDR) pathogens. However, the major hindrance for phage therapy is the lack of a rapid procedure to harness broad host range phages. Hitherto in vogue, lytic phage isolation methods are based on conventional single host enrichment (M1). Limitation to the available methods includes a higher number of steps, additional instrumentation, cost and time involved in the screening of samples and more recovery of narrow host range phages.To improve the conventional method of isolation, a multiple host enrichment approach (modified method; M2) is developed and validated with a classical approach using 24 MDR extended-spectrum β-lactamase producing (ESBL) E. coli and universal coliphage host E. coli NCIM 2089. A total of 58 phages were isolated using both the methods (27 phages from M1 and 31 phages from M2) and were categorized, based on the DNA restriction digestion pattern, to 25 groups with a maximum host range of 17 in host range analysis. Even though there is no significant difference (P > 0.01) in recovering number of phages between M1 and M2 methods, excepting in one occasion where MFB13 host yielded 3 more morphologically distinct phages in M2 (p ≤ 0.05), the M2 approach was better in terms of reduction in time (4.72%) and cost (23.5%) and same instrumentation requirement. This emphasizes that the proposed method has the potential to yield broad host range lytic phages against localized strain repository of AMR E. coli which can be leading to its application in food, food contact surfaces as well as phage therapy.

大肠杆菌已被列为重要的抗菌素耐药性病原体，对人类健康构成威胁。随着广泛的AMR，溶菌性噬菌体仍然是控制多药耐药性（MDR）病原体的抗生素的有前途的替代品。但是，噬菌体治疗的主要障碍是缺乏利用广泛宿主范围噬菌体的快速程序。迄今为止，裂解噬菌体分离方法是基于常规的单宿主富集（M1）。可用方法的局限性包括步骤数量增加，样品筛选涉及更多的仪器，成本和时间以及窄宿主范围噬菌体的更多回收率。为了改善常规分离方法，可采用多宿主富集方法（改良方法；常规方法）。大肠杆菌和通用大肠杆菌噬菌体宿主大肠杆菌NCIM2089。使用这两种方法共分离出58个噬菌体（M1中的27个噬菌体和M2中的31个噬菌体），并根据DNA限制性酶切模式分为25个组主机范围分析中的最大主机范围为17。尽管M1和M2方法之间的噬菌体回收率没有显着差异（P> 0.01），但在一种情况下，MFB13宿主在M2中产生了3种形态不同的噬菌体（p≤0.05），但M2方法在减少时间（4.72％）和成本（23.5％）以及相同的仪器要求。这强调了所提出的方法有可能针对AMR大肠杆菌的局部菌株库产生广泛的宿主范围裂解噬菌体 这可能导致其在食品，食品接触表面以及噬菌体治疗中的应用。