College of Food Science and Nutritional Engineering, China Agricultural Univ., Beijing 100083, China.
J Food Sci. 2010 Sep;75(7):M503-7. doi: 10.1111/j.1750-3841.2010.01776.x.
The effects of UV-C radiation on microbial growth in vitro (Monilinia fruticola) and in inoculated Yali pears (Pyrus bretschneideri Rehd.) were investigated. Moreover, postharvest quality and the activities of defense and antioxidant enzymes were analyzed after the pears were exposed to UV-C irradiation at an energy level of 5 kJ m⁻².The results showed that spore germination of M. fructicola was significantly inhibited by each of the 3 doses (1, 5, and 10 kJ m⁻²) in vitro. In the in vivo assays, lesion diameter on the fruit being inoculated before or after the UV-C treatment was both significantly lower than that on the fruit of control. Meanwhile, the activities of phenylalanine ammonia lyase, β-1,3-glucanase, superoxide dismutase, catalase, and glutathione reductase were induced to high levels by UV-C treatment. We conclude that UV-C treatment could reduce postharvest disease by the germicidal and induced effects and maintain the quality by enhancing the antioxidant enzyme activities.
UV-C radiation has recently been proposed as a new technology to avoid chemical fungicides. However, there are few studies regarding the effect of UV-C treatment on Yali pear. In this study, we found that 5 kJ m⁻² UV-C irradiation can control postharvest disease and maintain the quality of Yali pear. This method may be applied to reduce the decay of Yali pears during exporting and storage.
研究了 UV-C 辐射对体外（Monilinia fruticola）和接种的鸭梨（Pyrus bretschneideri Rehd.）中微生物生长的影响。此外，在鸭梨暴露于 5 kJ m⁻² 的 UV-C 辐射下后，分析了其采后品质和防御及抗氧化酶的活性。结果表明，3 种剂量（1、5 和 10 kJ m⁻²）在体外均显著抑制了 M. fructicola 的孢子萌发。在体内试验中，在 UV-C 处理前后接种的果实的病斑直径均明显小于对照果实。同时，UV-C 处理诱导苯丙氨酸解氨酶、β-1,3-葡聚糖酶、超氧化物歧化酶、过氧化氢酶和谷胱甘肽还原酶的活性升高。我们得出结论，UV-C 处理可以通过杀菌和诱导作用来减少采后病害，并通过增强抗氧化酶活性来保持品质。
UV-C 辐射最近被提议作为一种避免使用化学杀菌剂的新技术。然而，关于 UV-C 处理对鸭梨的影响的研究很少。在本研究中，我们发现 5 kJ m⁻² 的 UV-C 辐射可以控制鸭梨的采后病害并保持其品质。这种方法可能应用于减少鸭梨在出口和储存过程中的腐烂。
