短波紫外线对双孢蘑菇采后褐变的影响和作用机理研究

双孢蘑菇是世界上产量最大的食用菌，褐变是其采后贮运过程中主要问题。异常生理变化和微生物侵染均会导致双孢蘑菇褐变，影响商品价值。近年来，绿色、方便、广谱杀菌、无污染、经济的短波紫外线（UV-C）作为非热杀菌技术的应用和机理研究受到关注，对诱导果蔬抗病性和功能成分含量的提高、产品表面杀菌和褐变调控有明显效果。本项目以双孢蘑菇为实验材料，采用现代分析测试手段，研究UV-C处理对双孢蘑菇采后功能营养成分、酶系统以及相关蛋白表达、双孢蘑菇表面形态与组织超微结构、致病微生物及双孢蘑菇-病原菌互作机制的影响，以期从生理生化、酶蛋白、组织结构、微生物角度研究UV-C处理对双孢蘑菇采后褐变的影响效应和机理，为双孢蘑菇采后褐变调控提供理论基础和技术参考。本项目的实施对探索食用菌新的保鲜手段具有重要意义，也为UV-C在新鲜农产品采后保鲜加工过程中成为单元操作工艺提供理论依据。

Button mushrooms (Agaricus bisporus) is the most popular edible fungi in the world. Browning is a common phenomenon in mushroom during post-harvest storage and transportation, which decreases the commercial value of the product. Both abnormal physiology changes and bacteria infection can cause the browning of mushrooms. Ultraviolet C (UV-C) is a promising non-thermal processing technology for fresh produce , because it is easy to use and lethal to most types of microorganisms, it does not generate chemical residues and it is a cold process that can be effective at low cost in comparison with other sanitiziation methods. It has been shown that UV-C induces decay resistance and bioactive and functional components, inactivates foodborne human pathogens and controls browning of several fresh fruits and vegetables. In this proposed study, the effect of UV-C treatment on the functional nutrients, enzyme system, protein expression, surface morphology, tissue ultrastructure, bacteria, and host-bacteria interaction will be investigated by modern analysis methods. Mechanism of application of UV-C on mushrooms will be explored on the base of physiology and biochemistry, enzymology, tissue structure and bacterial inactivation, which will provide scientific basis and theory for the browning control of mushroom after harvest. The execution of this proposed research project is imperative for the development of the new non-thermal postharvest technology which will enable the industry to adopt UV-C technology as a unit operation for the storage and processing of mushroom and fresh produce in general.