The white beetroot cv. Śnieżna Kula is the first betanin-free beetroot registered in the European Union. The aim of this study was to compare the phenolic acids profile and antioxidant capacity of leaves of white (SK) and red (CC) beetroots and red (LC) and white (BL) Swiss chard growing in Poland. LC leaves were the richest source of total phenolics (16.55 mg GAE/g FW) and phenolic acids (1.81 mg/g FW), while the highest content of flavonoids was determined in CC leaves (1.6 mg QE/g FW). The highest antiradical activity was observed for LC, whereas CC extract exhibited the highest chelating power. BL and CC leaf extracts demonstrated high LOX inhibitory potential (EC₅₀ = 53.23 and 56.97 mg FW/mL, respectively). An uncompetitive type of LOX inhibition was obtained for all extracts. SK extracts demonstrated the highest XO inhibitory activity (EC₅₀ = 81.04 mg FW/mL). A noncompetitive type of XO inhibition was obtained in both extracts from red leaves (CC and LC), whereas an uncompetitive mode of inhibition was observed in the case of white leaf (SK and LC) extracts. Thus, it can be assumed that the presence of betanin influences the XO inhibition mechanism.

中文翻译：

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白甜菜根叶作为抗氧化剂和抗炎化合物的新来源。


白甜菜根CV。 Śnieżna Kula 是第一个在欧盟注册的不含甜菜碱的甜菜根。本研究的目的是比较波兰生长的白色（SK）和红色（CC）甜菜根以及红色（LC）和白色（BL）瑞士甜菜叶子的酚酸谱和抗氧化能力。 LC叶是总酚类物质（16.55 mg GAE/g FW）和酚酸（1.81 mg/g FW）最丰富的来源，而CC叶中类黄酮含量最高（1.6 mg QE/g FW）。 LC 的抗自由基活性最高，而 CC 提取物则表现出最高的螯合能力。 BL 和 CC 叶提取物表现出较高的 LOX 抑制潜力（EC ₅₀分别 = 53.23 和 56.97 mg FW/mL）。所有提取物均获得非竞争性的 LOX 抑制。 SK 提取物表现出最高的 XO 抑制活性（EC ₅₀ = 81.04 mg FW/mL）。在两种红叶提取物（CC 和 LC）中均获得非竞争性 XO 抑制，而在白叶（SK 和 LC）提取物中观察到非竞争性抑制模式。因此，可以假设甜菜苷的存在影响 XO 抑制机制。