Guan Yuge, Hu Wenzhong, Jiang Aili, Xu Yongping, Zhao Manru, Yu Jiaoxue, Ji Yaru, Yang Xiaozhe, Feng Ke
School of Bioengineering, Dalian University of Technology, Dalian 116024, China.
College of Life Science, Dalian Minzu University, Dalian 116600, China; Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian 116600, China.
Food Res Int. 2020 Nov;137:109565. doi: 10.1016/j.foodres.2020.109565. Epub 2020 Jul 28.
To explore the effect of cutting style on the biosynthesis of phenolic compounds and cellular antioxidant capacity in wounded broccoli subjected to different cutting styles (heads, florets, 1/2 florets and shredded florets), the mechanism of the accumulation of phenolic compounds was investigated at the transcriptional level, and cellular antioxidant capacity was measured using a breast cancer cell MCF-7 culture model. The results indicated that the relative expression of the genes encoding phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase and 4-coumarin coenzyme A ligase, three enzymes involved in phenylpropanoid metabolism, was upregulated and that contributed to the synthesis of individual phenolic compounds, including catechin, hydroxybenzoic acid, chlorogenic acid, caffeic acid, sinapic acid, catechin gallate, rutin, cinnamic acid and quercetin. This research constructes the phenol synthesis pathway in wounded broccoli. Moreover, the relative expression of critical genes including superoxide dismutase, peroxidase, catalase, glutathione peroxidase and glutathione reductase involved in the metabolism of reactive oxygen species (ROS) increased, resulting in enhanced antioxidant capacity in wounded broccoli. Cell antioxidant capacity (CAA) of heads, florets, 1/2 florets and shredded florets increased by 52.7%, 59.2%, 64.8% and 86.5%, respectively, compared to whole broccoli. The enhancement of CAA was greater as the intensity of wounding increased, indicating that enhancement of antioxidant activity occurred at the cellular level. This research helps provide a reliable and persuasive theoretical basis for nutritional value assessment at the cellular level in wounded broccoli.
为探究不同切割方式（整颗、小花、半小花和碎小花）对受伤西兰花中酚类化合物生物合成及细胞抗氧化能力的影响，在转录水平上研究了酚类化合物积累的机制，并使用乳腺癌细胞MCF-7培养模型测定了细胞抗氧化能力。结果表明，参与苯丙烷代谢的三种酶——编码苯丙氨酸解氨酶、肉桂酸4-羟化酶和4-香豆酸辅酶A连接酶的基因的相对表达上调，这有助于儿茶素、羟基苯甲酸、绿原酸、咖啡酸、芥子酸、儿茶素没食子酸酯、芦丁、肉桂酸和槲皮素等单个酚类化合物的合成。本研究构建了受伤西兰花中的酚类合成途径。此外，参与活性氧（ROS）代谢的关键基因包括超氧化物歧化酶、过氧化物酶、过氧化氢酶、谷胱甘肽过氧化物酶和谷胱甘肽还原酶的相对表达增加，导致受伤西兰花的抗氧化能力增强。与完整西兰花相比，整颗、小花、半小花和碎小花的细胞抗氧化能力（CAA）分别提高了52.7%、59.2%、64.8%和86.5%。随着损伤强度的增加，CAA的增强更为显著，表明抗氧化活性的增强发生在细胞水平。本研究有助于为受伤西兰花细胞水平的营养价值评估提供可靠且有说服力的理论依据。
