Aghdam Morteza Soleimani, Alikhani-Koupaei Majid, Khademian Raheleh
Department of Horticultural Science, Imam Khomeini International University, Qazvin, Iran.
Department of Production Engineering and Plant Genetics, Faculty of Agriculture, Higher Education Complex of Saravan, Saravan, Iran.
Front Nutr. 2021 Apr 1;8:609217. doi: 10.3389/fnut.2021.609217. eCollection 2021.
During postharvest life, broccoli suffers from floret yellowing confining its economic and nutritional value. The objective of the present study was to explore the mechanisms employed by phytosulfokine α (PSKα) at 150 nM for delaying floret yellowing in broccoli during storage at 4°C for 28 days. Our results showed that the higher endogenous accumulation of hydrogen sulfide (HS) resulting from the higher gene expression and activities of l-cysteine desulfhydrase () and d-cysteine desulfhydrase () in broccoli floret treated with 150 nM PSKα may serve as an endogenous signaling molecule for delaying senescence. Moreover, the suppressed ethylene biosynthesis in broccoli floret treated with 150 nM PSKα might be ascribed to lower gene expression and activities of ACC synthase () and ACC oxidase (). Furthermore, lower gene expression and activities of Mg dechelatase (), pheophytinase (), and pheophorbide a oxygenase () might be the reasons for the higher accumulation of chlorophyll in broccoli floret treated with 150 nM PSKα. Based on our findings, exogenous PSKα application could be employed as signaling bioactive hormone for retarding floret yellowing of broccoli during storage at 4°C for 28 days.
在采后贮藏期间，西兰花会出现小花黄化现象，从而限制其经济价值和营养价值。本研究的目的是探究150 nM植物硫肽素α（PSKα）在4℃贮藏28天期间延缓西兰花小花黄化的作用机制。我们的结果表明，用150 nM PSKα处理的西兰花小花中，由于L-半胱氨酸脱硫酶（）和D-半胱氨酸脱硫酶（）基因表达和活性较高，导致硫化氢（HS）的内源性积累增加，这可能作为一种内源性信号分子来延缓衰老。此外，用150 nM PSKα处理的西兰花小花中乙烯生物合成受到抑制，这可能归因于ACC合酶（）和ACC氧化酶（）的基因表达和活性较低。此外，Mg螯合酶（）、脱镁叶绿素酶（）和脱镁叶绿酸a加氧酶（）的基因表达和活性较低，可能是用150 nM PSKα处理的西兰花小花中叶绿素积累较高的原因。基于我们的研究结果，外源施用PSKα可作为一种信号生物活性激素，在4℃贮藏28天期间延缓西兰花小花黄化。
