Key Laboratory for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, PR China.
Key Laboratory of State Forestry Administration on Biodiversity Conservation in Southwest China, Southwest Forestry University, Kunming 650224, PR China.
Food Chem. 2019 Jun 15;283:92-100. doi: 10.1016/j.foodchem.2018.12.078. Epub 2018 Dec 23.
This study was to evaluate the effect of graft copolymer (CTS-g-SA) of chitosan (CTS) and salicylic acid (SA) on the storability of grapefruit fruits during postharvest storage. Results indicate that the graft copolymer treatment significantly depressed green mold caused by Penicillium digitatum. The graft copolymer application kept fruit firmness without impairing the fruit quality. Moreover, the graft copolymer treatment inhibited the activity and gene expression of cell wall-modifying enzymes such as polygalacturonase, cellulase, pectin methylesterase, α-l-arabinofuranosidase, β-galactosidase, and suppressed the modification of cell wall components including covalently bound polysaccharide (sodium carbonate soluble pectin, 24% KOH-soluble fraction), which were associated with fruit softening. These results suggested that graft copolymer application can be recognized as a postharvest technique to suppress rotting and delay softening through inhibiting solubilization of cell wall polysaccharides.
本研究评估了壳聚糖（CTS）和水杨酸（SA）接枝共聚物（CTS-g-SA）对采后贮藏期间葡萄柚果实贮藏期的影响。结果表明，接枝共聚物处理显著抑制了由指状青霉（Penicillium digitatum）引起的青霉病。接枝共聚物的应用保持了果实的硬度，而不会损害果实的品质。此外，接枝共聚物处理抑制了细胞壁修饰酶的活性和基因表达，如多聚半乳糖醛酸酶、纤维素酶、果胶甲酯酶、α-l-阿拉伯呋喃糖苷酶、β-半乳糖苷酶，并抑制了细胞壁成分的修饰，包括共价结合多糖（碳酸钠可溶性果胶、24%KOH 可溶性部分），这些与果实软化有关。这些结果表明，接枝共聚物的应用可以被认为是一种采后技术，通过抑制细胞壁多糖的溶解来抑制腐烂和延缓软化。
