Ono Yui, Iwahashi Hitoshi
The Graduate School of Applied Biological Sciences, Gifu University, Tokai National Higher Education and Research System, Yanagido 1-1, Gifu City, Gifu prefecture, Japan.
Biochem Biophys Rep. 2022 Feb 4;30:101221. doi: 10.1016/j.bbrep.2022.101221. eCollection 2022 Jul.
The photocatalytic activity of titanium dioxide is widely utilized in science and technology. In the biological field, titanium dioxide is believed to be a disinfectant because it produces reactive oxygen species (ROS). However, there are multiple types of ROS such as hydroxyl radicals, superoxide anions, singlet oxygen, and hydrogen peroxide. In this study, we attempted to characterize the various mechanisms and roles of ROS in disinfection. Surprisingly, we found that titanium dioxide protected yeast cells from ultraviolet irradiation. We characterized the ROS produced under these conditions. The production of hydroxyl radicals and superoxide anions was confirmed; however, glucose in the yeast medium scavenged hydroxyl radicals. The photocatalytic activity of titanium dioxide produced oxidative products and reductive products, as oxidation and reduction occurred simultaneously. Once hydroxyl radicals are scavenged, the photocatalytic activity of titanium dioxide produces a reductive environment for fermenting yeast cells and protects them from oxidative stress by ultraviolet irradiation.
二氧化钛的光催化活性在科学技术中得到了广泛应用。在生物领域，二氧化钛被认为是一种消毒剂，因为它能产生活性氧（ROS）。然而，ROS有多种类型，如羟基自由基、超氧阴离子、单线态氧和过氧化氢。在本研究中，我们试图表征ROS在消毒过程中的各种机制和作用。令人惊讶的是，我们发现二氧化钛能保护酵母细胞免受紫外线照射。我们对在这些条件下产生的ROS进行了表征。羟基自由基和超氧阴离子的产生得到了证实；然而，酵母培养基中的葡萄糖清除了羟基自由基。二氧化钛所具有的光催化活性会产生氧化产物和还原产物，因为氧化和还原是同时发生的。一旦羟基自由基被清除，二氧化钛的光催化活性就会为发酵酵母细胞产生一个还原环境，并保护它们免受紫外线照射所带来的氧化应激。
