Department of Characterization, Quality and Safety, Institute of Food Science, Technology and Nutrition (ICTAN-CSIC), Ciudad Universitaria, E-28040 Madrid, Spain.
Int J Mol Sci. 2022 Nov 1;23(21):13304. doi: 10.3390/ijms232113304.
Short-term gaseous treatments improve rachis quality during table grape postharvest, but little is known about the mechanisms involved. In this work, we observed that the application of a 3-day CO treatment at 0 °C improved rachis browning of Superior Seedless and Red Globe bunches, affecting the non-enzymatic antioxidant system by reducing the total phenolic content, the antioxidant activity and the expression of different genes. Lipid peroxidation levels revealed lower oxidative stress in CO-treated rachis of both cultivars linked to the activation of the enzymatic antioxidant system. Furthermore, whereas a positive correlation was denoted between rachis browning and the accumulation of key ABA regulatory genes in Red Globe bunches, this effect was restricted to , a key synthetic ethylene gene, in Superior Seedless clusters. This work also corroborated the important role of ethylene-responsive factors in the beneficial effect of the gaseous treatment, not only in the berries but also in the rachis. Finally, the application of the gaseous treatment avoided the induction of cell wall-degrading enzyme-related genes in both cultivars, which could favor the maintenance of rachis quality. This work provides new insight into specific responses modulated by the gaseous treatment focused on mitigating rachis browning independently of the cultivar.
短期气体处理可改善葡萄采后穗轴品质，但涉及的机制知之甚少。在这项工作中，我们观察到，在 0°C 下进行为期 3 天的 CO 处理可改善 Superior Seedless 和 Red Globe 葡萄串穗轴褐变，通过降低总酚含量、抗氧化活性和不同基因的表达来影响非酶抗氧化系统。脂质过氧化水平表明，CO 处理可降低两种品种穗轴的氧化应激，这与酶抗氧化系统的激活有关。此外，虽然 Red Globe 葡萄穗轴褐变与 ABA 关键调节基因的积累呈正相关，但这种效应仅限于 Superior Seedless 葡萄穗轴，而 是关键的合成乙烯基因。这项工作还证实了乙烯反应因子在气体处理有益效果中的重要作用，不仅在浆果中，而且在穗轴中也是如此。最后，气体处理的应用避免了两种品种细胞壁降解酶相关基因的诱导，这有利于维持穗轴品质。这项工作为气体处理针对减轻穗轴褐变的具体响应提供了新的见解，而不依赖于品种。
