INRA, UR83 Recherches Avicoles, Fonction et Régulation des Protéines de l'Oeuf, Nouzilly, France.
J Food Prot. 2010 Sep;73(9):1604-12. doi: 10.4315/0362-028x-73.9.1604.
Hen egg white contains numerous molecules of interest for human health, including antimicrobial proteins. Little information is available concerning changes in the antimicrobial activity of egg white during storage; therefore, we analyzed the potential of egg white to inhibit growth of Salmonella enterica serovar Enteritidis following storage at 4, 20, or 37°C for 30 days prior to inoculation. Egg white displayed higher anti-Salmonella activity after a few days of storage at 20 and 37°C. The rate of increase in activity was more rapid and pronounced at the higher temperature. However, egg white stored at 20°C retained higher antimicrobial activity than that of egg white stored at 4 or 37°C, when the entire storage period is taken in consideration. In contrast, storage of egg at 37°C for more than 14 days reduced the bacteriostatic potential of egg white. Statistical analyses revealed a correlation between pH and the antimicrobial activity of egg white. Moreover, diminished antimicrobial activity was associated with degradation of ovalbumin and ovotransferrin, as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and mass spectrometry. However, the fluctuation in anti-Salmonella activity of egg white could not be related to any variation of trypsin-like, chymotrypsin-like, or gelatinolytic activities that potentially account for degradation of antimicrobial egg white proteins.
蛋清中含有许多对人类健康有益的分子，包括抗菌蛋白。关于蛋清在储存过程中抗菌活性的变化，目前所知甚少；因此，我们分析了蛋清在接种前于 4°C、20°C 或 37°C 储存 30 天后抑制肠炎沙门氏菌生长的潜力。蛋清在 20°C 和 37°C 下储存数天后显示出更高的抗沙门氏菌活性。在较高温度下，活性的增加速度更快、更明显。然而，从整个储存期来看，在 20°C 下储存的蛋清保留了比在 4°C 或 37°C 下储存的蛋清更高的抗菌活性。相比之下，在 37°C 下储存超过 14 天会降低蛋清的抑菌潜力。统计分析显示 pH 值与蛋清的抗菌活性之间存在相关性。此外，通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳和质谱评估，抗菌活性的降低与卵清白蛋白和卵转铁蛋白的降解有关。然而，蛋清抗沙门氏菌活性的波动与潜在负责抗菌蛋清蛋白降解的胰蛋白酶样、糜蛋白酶样或胶凝酶样活性的任何变化都没有关系。
