Influence of combined hot air and UV-C treatment on the antioxidant system of minimally processed broccoli (Brassica oleracea L. var. Italica)
Influence of combined hot air and UV-C treatment on the antioxidant system of minimally processed broccoli (Brassica oleracea L. var. Italica)
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DOI：
10.1016/j.lwt.2010.05.011
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发表时间：
2010-11-01
影响因子：
6
通讯作者：
Martinez, Gustavo A.
中科院分区：
文献类型：
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作者：
Lemoine, Maria L.;Chaves, Alicia R.;Martinez, Gustavo A.
西兰花衰老迅速，这会降低产品的营养质量。在这项研究中，对轻度加工的西兰花小花采用热风和短波紫外线（UV - C）联合处理，以研究它们在20℃储存期间对抗氧化系统的影响。处理后，UV - C和热的应用使总抗氧化剂水平立即提高了约13%。在对照和处理样本中，这些水平都低于初始值。然而，在储存期间，处理样本中也检测到较高的值（范围从12%到50%）。一般来说，处理后的小花中抗氧化剂含量较高与酚类物质（从10%到17%）和抗坏血酸（从11%到17%）水平升高相关。处理后的西兰花中酚类物质含量的增加与苯丙氨酸解氨酶（PAL）活性的提高相关。联合处理还影响参与清除活性氧物质的酶的活性。处理后检测到超氧化物歧化酶活性增加了约50%。在储存的最初几天，这种较高的活性约为40%。像过氧化氢酶和抗坏血酸过氧化物酶等清除过氧化氢的酶在储存末期表现出活性增强。联合处理使过氧化物酶（PDX）活性在处理后降低了约60%，在储存两天后降低了近50%，这表明该酶在过氧化氢解毒中的作用较小。总之，联合处理可能有助于增强对氧化分子的防御，这不仅是通过提高酚类物质和抗坏血酸的水平，而且还通过提高参与清除活性氧物质的酶的活性来实现的。（C）2010爱思唯尔有限公司。保留所有权利。
Broccoli develops a fast senescence that deteriorates the nutritional quality of the product. In this work, a combined treatment with hot air and UV-C were applied to minimally processed broccoli florets to investigate their effects on the antioxidant system during storage at 20 degrees C. Application of UV-C and heat enhanced by approximately 13% the levels of total antioxidants immediately after treatment These levels were lower than initials in both control and treated samples. Nevertheless, higher values (ranged from 12 to 50%) were also detected in treated samples during storage. In general, higher values of antioxidants were correlated with elevated levels of phenols (from 10 to 17%) and ascorbic acid (from 11 to 17%) in treated florets. The increment in the content of phenolics in treated broccolis was correlated to an increased phenylalanine ammonia lyase (PAL) activity. The combined treatment also affects the activity of enzymes involved in removal of reactive oxygen species. An increase of about 50% in superoxide dismutase activity was detected after treatment. During the first days of storage this higher activity was about 40%. Enzymes that remove H2O2 like catalase and ascorbate peroxidase showed an enhanced activity toward the end of storage. The combined treatment diminished the peroxidase (PDX) activity approximately 60% after the treatment and near 50% after two days of storage, suggesting a minor role of this enzyme in detoxification of H2O2. In conclusion, combined treatment may contribute to enhance the protection against oxidative molecules not only by increasing levels of phenolics and ascorbic acid but also by enhancing the activity of enzymes involved in removing reactive oxygen species. (C) 2010 Elsevier Ltd. All rights reserved.