Liu Ye, Yi Lanhua, Ruan Changqing, Yao Shixiang, Deng Lili, Zeng Kaifang
College of Food Science, Southwest University, Chongqing, China.
Food Storage and Logistics Research Center, Southwest University, Chongqing, China.
Front Microbiol. 2019 Jun 11;10:1273. doi: 10.3389/fmicb.2019.01273. eCollection 2019.
Utilizing antagonistic yeasts is a promising approach for managing postharvest decay of fruits. However, it is well established that various severe stresses encountered in the environment and production process cause the intracellular reactive oxygen species (ROS) accumulation in yeast cells, resulting in cell damage and loss of vitality. Here, proline has been shown to function as a cell protectant and inducer of biofilm formation able to increase the oxidative stress tolerance and the biocontrol ability of the antagonistic yeast . Addition of proline to cells induced a significant rise in superoxide dismutase (SOD) and catalase (CAT) activity in the early and late stages of oxidative stress, respectively, and increased the maroon pigment production that directly reduced intracellular iron content and indirectly diminished intracellular ROS levels and thus inhibited ROS- and iron-induced apoptosis. Treating cells with iron chelator tropolone yielded similar results. Pigment production induced by proline also enhanced the capability of biofilm formation of . These results suggested an important role for pigment of in response to oxidative stress. The abilities of proline to scavenge intracellular ROS and inhibit apoptosis, increase pigment production, and promote biofilm formation contribute to the improvements in oxidative stress tolerance and biocontrol efficacy of .
利用拮抗性酵母是控制水果采后腐烂的一种有前景的方法。然而，众所周知，在环境和生产过程中遇到的各种严重胁迫会导致酵母细胞内活性氧（ROS）积累，从而导致细胞损伤和活力丧失。在此，脯氨酸已被证明可作为细胞保护剂和生物膜形成诱导剂，能够提高拮抗性酵母的氧化应激耐受性和生物防治能力。向细胞中添加脯氨酸分别在氧化应激的早期和晚期诱导超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性显著升高，并增加了栗色色素的产生，这直接降低了细胞内铁含量，间接降低了细胞内ROS水平，从而抑制了ROS和铁诱导的细胞凋亡。用铁螯合剂托酚酮处理细胞也产生了类似的结果。脯氨酸诱导的色素产生也增强了生物膜形成能力。这些结果表明色素在应对氧化应激中起着重要作用。脯氨酸清除细胞内ROS、抑制细胞凋亡、增加色素产生和促进生物膜形成的能力有助于提高其氧化应激耐受性和生物防治效果。
