Impact of 1-MCP and Controlled Atmosphere on Physiological Disorders in Stored Pome Fruit: Biochemical Signatures of Oxidative Stress Metabolism

1-MCP 和受控气氛对贮藏仁果生理紊乱的影响：氧化应激代谢的生化特征

• 批准号: 419569-2011
• 负责人: Bozzo, Gale
• 金额: $ 4.6万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=551630
• 关键词: Impact; MCP; Controlled; Atmosphere; Physiological

In controlled atmosphere (CA) storage, the metabolic activity of pome fruit is decreased by controlling the oxygen and carbon dioxide partial pressures, as a supplement to a reduction in temperature. The optimal conditions are a compromise among: (i) maintaining firmness/quality; (ii) promoting uniform ripeness during re-warming; and, (iii) minimizing the incidence of physiological storage disorders such as scald and internal browning which can cause economic loss. CA conditions can result in an imbalance between oxidative and reductive (redox) processes at the cellular level and in the loss of endogenous antioxidants (e.g. ascorbate, NADPH) and accumulation of oxidative stress metabolites, like gamma-aminobutyrate (GABA) and gamma-hydroxybutyrate (GHB). In this proposal, we intend to investigate whether the shifts in redox and GABA metabolism are temporally associated with external injury and flesh browning in pears and apples stored under controlled atmosphere conditions. In addition, treatment of pome fruit with pre-storage chemicals, such as 1-methylcyclopropene or 1-MCP, aimed at preserving fruit quality via inhibition of ethylene mediated ripening may influence oxidative stress metabolism. The redox pairs and stress metabolites will be determined as a function of storage time and 1-MCP treatment via reverse-phase HPLC, GC-mass spectrometry, and with UV/Vis spectrophotometry. Also, we intend to investigate the relative importance of GHB production as a precursor to physiological disorders in apple fruit using a rapid-flowering line transformed with RNAi constructs of the GHB-forming enzyme, glyxoylate/succinic semialdehyde reductase. This project should lead to improved understanding of the mechanisms responsible for physiological disorders in stored apples and pears, and could contribute to improved storage protocols for maintaining quality of product, and the development of diagnostics/technologies for assessing injury potential and genetic engineering strategies for ameliorating physiological disorders during storage.

在可控大气（CA）储存中，通过控制氧气和二氧化碳分压来降低梨果实的代谢活性，作为降低温度的补充。最佳条件是：(i)保持坚固/质量；（ii）在复温过程中促进均匀成熟；（iii）尽量减少可能造成经济损失的生理储存障碍的发生率，如烫伤和内部褐变。CA条件可导致细胞水平氧化和还原（氧化还原）过程之间的不平衡，以及内源性抗氧化剂（如抗坏血酸、NADPH）的损失和氧化应激代谢物（如γ -氨基丁酸盐（GABA）和γ -羟基丁酸盐（GHB））的积累。在本研究中，我们打算研究受控环境下储存的梨和苹果的氧化还原和GABA代谢的变化是否与外伤和果肉褐变有关。此外，用1-甲基环丙烯或1-MCP等储藏前化学物质处理梨果，旨在通过抑制乙烯介导的成熟来保持果实品质，可能会影响氧化应激代谢。氧化还原对和应激代谢产物将通过反相HPLC、gc -质谱和紫外/可见分光光度法测定储存时间和1-MCP处理的函数。此外，我们打算利用一种快速开花品系，用RNAi构建的GHB形成酶glyxyoyate /琥珀酸半醛还原酶转化，研究GHB的产生作为苹果果实生理失调前兆的相对重要性。该项目将有助于提高对贮藏苹果和梨生理失调机制的理解，并有助于改进贮藏方案以保持产品质量，有助于开发评估潜在伤害的诊断/技术和改善贮藏期间生理失调的基因工程策略。