National Engineering Laboratory of Intelligent Food Technology and Equipment, Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Key Laboratory for Agro-Products Nutritional Evaluation of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Fuli Institute of Food Science, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China.
Ann N Y Acad Sci. 2017 Jun;1398(1):72-82. doi: 10.1111/nyas.13377. Epub 2017 Jun 15.
Phytochemicals are widely present in food and have been confirmed to be bioactive, thereby contributing to human health. However, some phytochemicals are sensitive to light owing to their structures and may suffer from photodegradation, especially when sensitizers exist, resulting in sensory quality change, nutrient loss in food, and even the formation of toxic compounds. The photooxidation of phytochemicals occurs through three different mechanisms: (1) by directly absorbing luminous energy, (2) with triplet-excited state sensitizers through electron transfer or proton transfer (type I photooxidation), and (3) with singlet oxygen produced by O (type II photooxidation). On the basis of these mechanisms, adequate antioxidants can be added to quench the triple-excited state sensitizers or singlet oxygen to protect against the photooxidation of phytochemicals in food. Here, we summarize and discuss the possible pathways and products of the photooxidation of phytochemicals that have been reported and the relationships between structures and photooxidation. We also propose some control measures, with special attention paid to the potential abilities of phytochemicals in the prevention of food photooxidation.
植物化学物质广泛存在于食物中，已被证实具有生物活性，从而对人类健康有益。然而，由于结构原因，一些植物化学物质对光敏感，可能会遭受光降解，尤其是存在敏化剂时，会导致感官质量变化、食物中营养物质损失，甚至形成有毒化合物。植物化学物质的光氧化通过三种不同的机制发生：（1）通过直接吸收光能，（2）通过三重激发态敏化剂通过电子转移或质子转移（I 型光氧化），以及（3）通过氧（O）产生的单线态氧（II 型光氧化）。基于这些机制，可以添加足够的抗氧化剂来猝灭三重激发态敏化剂或单线态氧，以防止食物中植物化学物质的光氧化。在这里，我们总结和讨论了已报道的植物化学物质光氧化的可能途径和产物，以及结构与光氧化之间的关系。我们还提出了一些控制措施，特别关注植物化学物质在预防食物光氧化方面的潜在能力。
