Exogenous antioxidants on quality of cabbage seeds

Abstract During seed germination there is production of reactive oxygen species, which, in a controlled way, are important to cell signaling and protection against pathogens, but, in excess, impair germination. Therefore, the objective of this study was to assess the action of different compounds on antioxidant mechanisms and enzymatic activation in cabbage seeds. Compounds like kojic acid, thymol and tyrosol were used to imbibe the cabbage seeds together with distilled water, and a control treatment without imbibition was used as well, with subsequent assessment by means of germination test, endosperm rupture, vigor, radicle protrusion, and assessment of seedling biochemical analyses by the activity of enzymes ascorbate peroxidase, catalase, superoxide dismutase and α-amylase. Data were subjected to analysis of variance and to the LSD means comparison test. Seeds treated with tyrosol presented higher results on the rupture of the endosperm, germination and vigor, and root development increased with use antioxidants. For the activity of antioxidant enzymes in seedlings, only kojic acid showed increase in the superoxide dismutase activity. There was also a reduction in the catalase activity with the use of thymol and tyrosol compounds compared to dry-seed assessments. After tyrosol treatment, ascorbate peroxidase enzyme was not detected, and water-imbibed seeds showed higher α-amylase activity. The use of antioxidant compounds has beneficial effects on cabbage seeds, and soaking with tyrosol led to better physiological quality, with activation of antioxidant defense mechanisms during germination.

摘要 种子萌发过程中会产生活性氧（reactive oxygen species），当其处于受控水平时，对细胞信号传导及病原菌抵御具有重要作用，但过量积累则会抑制种子萌发。为此，本研究旨在评估不同化合物对甘蓝种子抗氧化机制及酶激活过程的影响。本研究选用曲酸（kojic acid）、百里酚（thymol）及酪醇（tyrosol）与蒸馏水共同对甘蓝种子进行吸胀处理，同时设置无吸胀操作的对照组；随后通过萌发试验、胚乳破裂情况、种子活力、胚根突出情况，以及对抗坏血酸过氧化物酶（ascorbate peroxidase）、过氧化氢酶（catalase）、超氧化物歧化酶（superoxide dismutase）与α-淀粉酶活性的检测开展幼苗生化分析。数据采用方差分析及LSD均值多重比较检验进行统计分析。经酪醇处理的甘蓝种子在胚乳破裂率、萌发率及种子活力方面表现更优，且使用抗氧化剂可促进根系发育。对于幼苗抗氧化酶活性而言，仅曲酸处理组的超氧化物歧化酶活性有所提升。与干种子的检测结果相比，使用百里酚与酪醇处理可降低过氧化氢酶活性。经酪醇处理后，未检测到抗坏血酸过氧化物酶的活性；而仅经蒸馏水吸胀的种子则表现出更高的α-淀粉酶活性。综上，抗氧化化合物对甘蓝种子具有积极作用，其中酪醇浸种可提升种子生理品质，并在萌发过程中激活抗氧化防御机制。