Food Sci Technol Int. 2014 Jun;20(4):309-17. doi: 10.1177/1082013213484919.
Papaya fruits (Carica papaya L. cv 'Sui you 2') harvested with < 5% yellow surface at the blossom end were fumigated with 60 microL/L of nitric oxide for 3 h and then stored at 20 degrees C with 85% relative humility for 20 days. The effects of nitric oxide treatment on ethylene production rate, the activities of cell wall softening related enzymes including polygalacturonase, pectin methyl esterase, pectate lyase and cellulase and the levels of hormones including indole acetic acid, abscisic acid, gibberellin and zeatin riboside were examined. The results showed that papaya fruits treated with nitric oxide had a significantly lower rate of ethylene production and a lesser loss of firmness during storage. A decrease in polygalacturonase, pectin methyl esterase, pectate lyase and cellulase activities was observed in nitric oxide treated fruit. In addition, the contents of indole acetic acid, abscisic acid and zeatin riboside were reduced in nitric oxide treated fruit, but no significant reduction in the level of gibberellin was found. These results indicate that nitric oxide treatment can effectively delay the softening and ripening of papaya fruit, likely via the regulation of cell wall softening related enzymes and certain hormones.
番木瓜果实（Carica papaya L. cv 'Sui you 2'）在收获时，花端表面有<5%的黄色，用 60 微升/升的一氧化氮熏蒸 3 小时，然后在 20°C、相对湿度 85%的条件下贮藏 20 天。研究了一氧化氮处理对乙烯释放率、细胞壁软化相关酶（包括多聚半乳糖醛酸酶、果胶甲酯酶、果胶裂解酶和纤维素酶）活性以及激素（包括吲哚乙酸、脱落酸、赤霉素和玉米素核苷）水平的影响。结果表明，用一氧化氮处理的番木瓜果实乙烯释放率显著降低，贮藏过程中硬度损失较小。在一氧化氮处理的果实中，多聚半乳糖醛酸酶、果胶甲酯酶、果胶裂解酶和纤维素酶的活性下降。此外，一氧化氮处理的果实中吲哚乙酸、脱落酸和玉米素核苷的含量降低，但赤霉素的水平没有明显降低。这些结果表明，一氧化氮处理可以有效延缓番木瓜果实的软化和成熟，可能是通过调节细胞壁软化相关酶和某些激素来实现的。
