Ren Gang, Liu Yaping, Deng Bing, Wang Yu, Lin Wenyan, Zhang Yulei, Di Jianbing, Yang Jiali
College of Food Science and Engineering, Shanxi Agricultural University, Jinzhong 030800, China.
Foods. 2022 Oct 8;11(19):3123. doi: 10.3390/foods11193123.
The yellowing of green broccoli is a phenomenon that indicates a serious deterioration of freshness. The green broccoli has been more popular than the yellow one, with its higher nutritional value. Chitosan coating has been employed in vegetables for green-keeping, owing to its functions of regulating chlorophyll metabolism and antioxidant defense. Furthermore, selenium was commonly utilized in the pre-harvest of fruit and vegetables as an antioxidant and chlorophyll regulator. However, there have not yet been concerns about the effects of selenium-chitosan on vegetable yellowing. This study first investigated the impact of selenium-chitosan on the quality of fresh-cut broccoli yellowing during storage by analyzing the chromatic aberration and phytochromes. Additionally, then, the gene expression related to chlorophyll metabolism (, , , , ), carotenoid metabolism (, , , , ), and transcription factors (, , , , ) were analyzed using the RT-qPCR technique. Test results showed that treatment with selenium-chitosan can slow down the reduction in h° (Hue angle values) and reduce ethylene release rate and respiration intensity. Via the molecular approach, it was further identified that this treatment could inhibit chlorophyll degradation and carotenoid biosynthesis, accompanied by lower expression levels of heme oxygenase (), chlorophyllide A oxygenase (), violaxanthin de-epoxidase (), β-carotene 3-hydroxylase (), , basic leucine zipper (), , and , and higher expression levels of magnesium chelatase subunit I () and lycopene ε-cyclase () genes. This work can be used to explore the molecular mechanism of selenium-chitosan in inhibiting the yellowing of fresh-cut broccoli. This study will be of great economic importance in marketing and export by increasing the shelf life of fruits and vegetables.
绿色西兰花变黄是新鲜度严重下降的一种现象。绿色西兰花比黄色西兰花更受欢迎，其营养价值更高。壳聚糖涂层因其调节叶绿素代谢和抗氧化防御的功能，已被用于蔬菜保鲜。此外，硒在果蔬采前常作为抗氧化剂和叶绿素调节剂使用。然而，尚未有人关注硒 - 壳聚糖对蔬菜变黄的影响。本研究首先通过分析色差和植物色素，研究了硒 - 壳聚糖对鲜切西兰花贮藏期间变黄品质的影响。此外，随后使用RT - qPCR技术分析了与叶绿素代谢（，，，，）、类胡萝卜素代谢（，，，，）和转录因子（，，，，）相关的基因表达。试验结果表明，用硒 - 壳聚糖处理可以减缓h°（色相角值）的降低，并降低乙烯释放速率和呼吸强度。通过分子方法进一步确定，这种处理可以抑制叶绿素降解和类胡萝卜素生物合成，同时血红素加氧酶（）、叶绿素酸酯A加氧酶（）、紫黄质脱环氧化酶（）、β - 胡萝卜素3 - 羟化酶（）、，碱性亮氨酸拉链（）、，和，的表达水平较低，而镁螯合酶亚基I（）和番茄红素ε - 环化酶（）基因的表达水平较高。这项工作可用于探索硒 - 壳聚糖抑制鲜切西兰花变黄的分子机制。本研究通过延长果蔬保质期，在市场营销和出口方面将具有重要的经济意义。
