Kitsiou Melina, Purk Lisa, Ioannou Christina, Wantock Thomas, Sandison Gavin, Harle Thomas, Gutierrez-Merino Jorge, Klymenko Oleksiy V, Velliou Eirini
School of Chemistry and Chemical Engineering, University of Surrey, Guildford GU2 7XH, UK; Centre for 3D Models of Health and Disease, Division of Surgery and Interventional Science, University College London, London W1W 7TY, UK.
School of Chemistry and Chemical Engineering, University of Surrey, Guildford GU2 7XH, UK.
Int J Food Microbiol. 2023 Dec 2;406:110395. doi: 10.1016/j.ijfoodmicro.2023.110395. Epub 2023 Sep 12.
The demand for products that are minimally processed and produced in a sustainable way, without the use of chemical preservatives or antibiotics have increased over the last years. Novel non-thermal technologies such as cold atmospheric plasma (CAP) and natural antimicrobials such as grape seed extract (GSE) are attractive alternatives to conventional food decontamination methods as they can meet the above demands. The aim of this study was to investigate the microbial inactivation potential of GSE, CAP (in this case, a remote air plasma with an ozone-dominated RONS output) and their combination against L. monocytogenes on five different 3D in vitro models of varying rheological, structural, and biochemical composition. More specifically, we studied the microbial dynamics, as affected by 1 % (w/v) GSE, CAP or their combination, in three monophasic Xanthan Gum (XG) based 3D models of relatively low viscosity (1.5 %, 2.5 % and 5 % w/v XG) and in a biphasic XG/Whey Protein (WPI) and a triphasic XG/WPI/fat model. A significant microbial inactivation (comparable to liquid broth) was achieved in presence of GSE on the surface of all monophasic models regardless of their viscosity. In contrast, the GSE antimicrobial effect was diminished in the multiphasic systems, resulting to only a slight disturbance of the microbial growth. In contrast, CAP showed better antimicrobial potential on the surface of the complex multiphasic models as compared to the monophasic models. When combined, in a hurdle approach, GSE/CAP showed promising microbial inactivation potential in all our 3D models, but less microbial inactivation in the structurally and biochemically complex multiphasic models, with respect to the monophasic models. The level of inactivation also depended on the duration of the exposure to GSE. Our results contribute towards understanding the antimicrobial efficacy of GSE, CAP and their combination as affected by robustly controlled changes of rheological and structural properties and of the biochemical composition of the environment in which bacteria grow. Therefore, our results contribute to the development of sustainable food safety strategies.
在过去几年中，对以可持续方式生产且极少加工、不使用化学防腐剂或抗生素的产品的需求有所增加。新型非热技术，如冷大气等离子体（CAP）和天然抗菌剂，如葡萄籽提取物（GSE），是传统食品去污方法的有吸引力的替代方案，因为它们可以满足上述需求。本研究的目的是研究GSE、CAP（在本研究中，是一种以臭氧为主的活性氧氮化物输出的远程空气等离子体）及其组合对五种不同流变学、结构和生化组成的3D体外模型上的单核细胞增生李斯特菌的微生物灭活潜力。更具体地说，我们研究了在三种基于低粘度（1.5%、2.5%和5% w/v）黄原胶（XG）的单相3D模型以及双相XG/乳清蛋白（WPI）和三相XG/WPI/脂肪模型中，受1%（w/v）GSE、CAP或其组合影响的微生物动态。在所有单相模型表面，无论其粘度如何，在GSE存在的情况下都实现了显著的微生物灭活（与液体肉汤相当）。相比之下，GSE在多相系统中的抗菌效果减弱，仅导致微生物生长略有干扰。相比之下，与单相模型相比，CAP在复杂多相模型表面显示出更好的抗菌潜力。当以栅栏技术组合使用时，GSE/CAP在我们所有的3D模型中都显示出有前景的微生物灭活潜力，但相对于单相模型，在结构和生化复杂的多相模型中的微生物灭活较少。灭活水平还取决于暴露于GSE的持续时间。我们的结果有助于理解GSE、CAP及其组合的抗菌效果，这些效果受细菌生长环境的流变学、结构特性和生化组成的严格控制变化的影响。因此，我们的结果有助于可持续食品安全策略的发展。
