Abstract：
BACKGROUND: The first step in the contamination of leafy vegetables by human pathogens is their attachment to the leaf surface. The success of this is influenced strongly by the physical and chemical characteristics of the surface itself (number and size of stomata, presence of trichomes and veins, epicuticular waxes, hydrophobicity, etc.). This study evaluated the attachment of Salmonella enterica to 30 baby-leaf salads and tested whether the differences found among them were related to the following leaf traits: hydrophobicity, roughness, and epicuticular waxes.
RESULTS: Differences in susceptibility to contamination by S. enterica were found between the 30 baby-leaf salads investigated. The lowest attachment was found in wild lettuce (Lactuca serriola L.) and lamb\'s lettuce \'Trophy F1\' (Valerianella locusta [L.] Laterr.), with values of 1.63 ± 0.39 Log(CFU/cm2) and 1.79 ± 0.54 Log(CFU/cm2), respectively. Attachment was correlated with hydrophobicity (measured as contact angle) (r = -0.39) and epicuticular waxes (r = -0.81) but not with roughness (r = 0.24). The most important wax components for attachment were alcohols and, in particular, the three-dimensional (3D) wax crystals of C26 alcohol, but fatty acids probably also had a role. Both these compounds increased hydrophobicity. The presence of thymol, whose antimicrobial properties are well known, was found in lamb\'s lettuce.
CONCLUSIONS: The findings of this study can help to predict and control the attachment and contamination of leafy salads by enterobacteria. They also provide useful information for breeding programs aiming to develop cultivars that are less susceptible to human pathogens, enhancing the food safety of vegetables. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
RESULTS: Differences in susceptibility to contamination by S. enterica were found between the 30 baby-leaf salads investigated. The lowest attachment was found in wild lettuce (Lactuca serriola L.) and lamb\'s lettuce \'Trophy F1\' (Valerianella locusta [L.] Laterr.), with values of 1.63 ± 0.39 Log(CFU/cm2) and 1.79 ± 0.54 Log(CFU/cm2), respectively. Attachment was correlated with hydrophobicity (measured as contact angle) (r = -0.39) and epicuticular waxes (r = -0.81) but not with roughness (r = 0.24). The most important wax components for attachment were alcohols and, in particular, the three-dimensional (3D) wax crystals of C26 alcohol, but fatty acids probably also had a role. Both these compounds increased hydrophobicity. The presence of thymol, whose antimicrobial properties are well known, was found in lamb\'s lettuce.
CONCLUSIONS: The findings of this study can help to predict and control the attachment and contamination of leafy salads by enterobacteria. They also provide useful information for breeding programs aiming to develop cultivars that are less susceptible to human pathogens, enhancing the food safety of vegetables. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
摘要：
背景：人类病原体污染叶类蔬菜的第一步是它们附着在叶片表面。这种方法的成功受到表面本身的物理和化学特性（气孔的数量和大小，毛状体和静脉的存在，表皮蜡,疏水性,等。).这项研究评估了肠道沙门氏菌对30种幼叶沙拉的附着，并测试了它们之间发现的差异是否与以下叶片特征有关：疏水性，粗糙度,和表皮蜡。
结果：在所调查的30个婴儿叶沙拉中发现了肠链球菌污染易感性的差异。在野生生菜（LactucaserriolaL.）和羔羊的生菜“奖杯F1”（Valerianellalocusta[L.]Laterr.),值为1.63±0.39Log(CFU/cm2)和1.79±0.54Log(CFU/cm2),分别。附着与疏水性（以接触角测量）（r=-0.39）和表皮蜡（r=-0.81）相关，但与粗糙度（r=0.24）无关。用于连接的最重要的蜡组分是醇和,特别是,C26醇的三维（3D）蜡晶体，但是脂肪酸可能也有作用。这两种化合物都增加了疏水性。百里酚的存在，其抗菌特性是众所周知的，是在羔羊的生菜中发现的。
结论：这项研究的结果可以帮助预测和控制肠杆菌对叶沙拉的附着和污染。它们还为旨在开发不易受人类病原体影响的品种的育种计划提供了有用的信息，提高蔬菜的食品安全。©2024作者（S）。约翰·威利父子有限公司代表化学工业学会出版的《食品和农业科学杂志》。
结果：在所调查的30个婴儿叶沙拉中发现了肠链球菌污染易感性的差异。在野生生菜（LactucaserriolaL.）和羔羊的生菜“奖杯F1”（Valerianellalocusta[L.]Laterr.),值为1.63±0.39Log(CFU/cm2)和1.79±0.54Log(CFU/cm2),分别。附着与疏水性（以接触角测量）（r=-0.39）和表皮蜡（r=-0.81）相关，但与粗糙度（r=0.24）无关。用于连接的最重要的蜡组分是醇和,特别是,C26醇的三维（3D）蜡晶体，但是脂肪酸可能也有作用。这两种化合物都增加了疏水性。百里酚的存在，其抗菌特性是众所周知的，是在羔羊的生菜中发现的。
结论：这项研究的结果可以帮助预测和控制肠杆菌对叶沙拉的附着和污染。它们还为旨在开发不易受人类病原体影响的品种的育种计划提供了有用的信息，提高蔬菜的食品安全。©2024作者（S）。约翰·威利父子有限公司代表化学工业学会出版的《食品和农业科学杂志》。
