Ni Peien, Wang Lei, Deng Bohan, Jiu Songtao, Ma Chao, Zhang Caixi, Almeida Adelaide, Wang Dapeng, Xu Wenping, Wang Shiping
School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
Microorganisms. 2020 Jun 2;8(6):837. doi: 10.3390/microorganisms8060837.
pv. (Psa) is the causative agent of the bacterial canker of kiwifruit spp.). Phage therapy has been suggested as a viable alternative approach to controlling this disease, but its efficacy is limited by the emergence of phage-resistant mutants. Carvacrol is an essential oil that may be useful for the control of Psa. Combination therapies can be used to overcome resistance development. Here, the combination of phages (single phage suspensions of phages PN05 and PN09, and a cocktail of both phages) and carvacrol was investigated in controlling Psa planktonic and biofilm forms in vitro. The phage therapy alone (with phages PN05 and PN09), and the carvacrol alone (minimum inhibitory concentration 2.0 mg/mL), inhibited Psa growth, but the combined effect of both therapies was more effective. The phages alone effectively inhibited Psa growth for 24 h, but Psa regrowth was observed after this time. The carvacrol (2.0 mg/mL) alone prevented the biofilm formation for 48 h, but did not destroy the pre-formed biofilms. The combined treatment, phages and carvacrol (2.0 mg/mL), showed a higher efficacy, preventing Psa regrowth for more than 40 h. In conclusion, the combined treatment with phages and carvacrol may be a promising, environment-friendly and cost-effective approach to controlling Psa in the kiwifruit industry.
丁香假单胞菌猕猴桃致病变种（Psa）是猕猴桃细菌性溃疡病的病原体。噬菌体疗法已被认为是控制这种疾病的一种可行替代方法，但其疗效受到噬菌体抗性突变体出现的限制。香芹酚是一种可能对控制Psa有用的精油。联合疗法可用于克服抗性的产生。在此，研究了噬菌体（噬菌体PN05和PN09的单噬菌体悬浮液以及两种噬菌体的混合物）与香芹酚联合控制体外Psa浮游和生物膜形式的效果。单独的噬菌体疗法（使用噬菌体PN05和PN09）以及单独的香芹酚（最低抑菌浓度2.0 mg/mL）均能抑制Psa生长，但两种疗法的联合效果更有效。单独的噬菌体可有效抑制Psa生长24小时，但此后观察到Psa重新生长。单独的香芹酚（2.0 mg/mL）在48小时内可防止生物膜形成，但不能破坏预先形成的生物膜。噬菌体与香芹酚（2.0 mg/mL）的联合处理显示出更高的疗效，可防止Psa重新生长超过40小时。总之，噬菌体与香芹酚联合处理可能是猕猴桃产业中控制Psa的一种有前景、环境友好且具有成本效益的方法。
