Panebianco Felice, Rubiola Selene, Chiesa Francesco, Civera Tiziana, Di Ciccio Pierluigi Aldo
Department of Veterinary Sciences, University of Turin, Italy.
Ital J Food Saf. 2022 Jun 29;11(2):10350. doi: 10.4081/ijfs.2022.10350. eCollection 2022 Jun 21.
Microbial biofilms existing in food industries have been implicated as important contamination sources of spoilage and pathogenic microorganisms in the finished products. Among the innovative strategies proposed to contrast biofilms in food environments, ozone is recognised as an environmentally friendly technology but there are few studies about its effect against bacterial biofilms. The objective of this study was to evaluate the effect of gaseous ozone (50 ppm for 6 h) in inhibition and eradication of biofilm formed by twenty-one dairyisolated spp. strains. Before ozone treatments, all isolates were screened for biofilm formation according to a previously described method. Strains were then divided in four groups: weak, weak/moderate, moderate/strong, and strong biofilm producers based on the biofilm biomass value of each isolate determined using the optical density (OD - 595 nm). Inhibition treatment was effective on the strain (C1) belonging to the weak producers' group, on all strains classified as weak/moderate producers, on two strains (C8 and C12) belonging to the group of moderate/strong producers and on one strain (C13) classified as strong producer. Conversely, eradication treatments were ineffective on all strains tested, except for the strain C4 which reduced its biofilm-forming abilities after exposure to ozone gas. In conclusion, gaseous ozone may be used to enhance existing sanitation protocols in food processing environments, but its application alone not seems sufficient to contrast spp. established biofilms.
食品工业中存在的微生物生物膜被认为是成品中腐败和致病微生物的重要污染源。在提出的用于对抗食品环境中生物膜的创新策略中，臭氧被认为是一种环境友好型技术，但关于其对细菌生物膜影响的研究较少。本研究的目的是评估气态臭氧（50 ppm，处理6小时）对21株从乳制品中分离出的菌株形成的生物膜的抑制和根除效果。在进行臭氧处理之前，根据先前描述的方法对所有分离株进行生物膜形成筛选。然后根据使用光密度（OD - 595 nm）测定的每个分离株的生物膜生物量值，将菌株分为四组：弱生物膜产生菌、弱/中度生物膜产生菌、中度/强生物膜产生菌和强生物膜产生菌。抑制处理对属于弱生物膜产生菌组的菌株（C1）、所有分类为弱/中度生物膜产生菌的菌株、属于中度/强生物膜产生菌组的两株菌株（C8和C12）以及分类为强生物膜产生菌的一株菌株（C13）有效。相反，除菌株C4在暴露于臭氧气体后其生物膜形成能力降低外，根除处理对所有测试菌株均无效。总之，气态臭氧可用于加强食品加工环境中现有的卫生规程，但其单独应用似乎不足以对抗已形成的生物膜。
