Kale (Brassica oleracea L. var. sabellica) biofortified with iodoquinolines: Effectiveness of enriching with iodine and influence on chemical composition

• Published in: Scientia horticulturae 2024-01, Vol.323, p.112519, Article 112519
• Main Authors: Krawczyk, Katarzyna Karolina, Smoleń, Sylwester, Wisła-Świder, Anna, Kowalska, Iwona, Kiełbasa, Daniel, Pitala, Joanna, Krzemińska, Joanna, Waśniowska, Justyna, Koronowicz, Aneta
• Format: Article
• Language: English
• Subjects: Biofortification; Iodine; Iodine deficiency; Iodoquinolines; Quinoline; RDA iodine
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/j.scienta.2023.112519

•Biofortification with iodoquinolines significantly increases the iodine content in kale.•Variety of kale has no effect on the amount of accumulated iodine.•Consumption of 50 and 100 g portions of biofortified kale would significantly cover the RDA for iodine.•Consumption of kale enriched with iodoquinolines is safe for consumers (HQ < 1.0).•Application of iodoquinolines do not have a negative effect on kale yields. Iodine is a trace element essential for the proper function of the human body, while quinoline derivatives demonstrate many health-promoting properties. Despite the obligatory iodization of table salt introduced by the World Health Organization, there is still a significant population worldwide at risk of iodine deficiency. Because of the need to reduce the dietary supply of table salt, it is necessary to search for new alternative sources of this mineral. The aim of this study was to determine the effectiveness of kale biofortification with iodoquinolines, to estimate daily iodine intake and to determine the effect of iodoquinolines on the yield as well as the chemical composition of two kale (Brassica oleracea L. var. sabellica) cultivars cv. ‘Oldenbor F1’ (green kale) and cv. ‘Redbor F1’ (red kale), cultivated in a hydroponic system. The applied compounds: KIO3, 8-Hydroxy-7-iodo-5-quinolinesulfonic acid, 5-Chloro-7-iodo-8-quinolinol and 5,7-diiodo-8-quinolinol, significantly increased iodine concentration in plants without having any effect on yields. Treatment with 8-Hydroxy-7-iodo-5-quinolinesulfonic acid for the iodine biofortification of plants was as effective as the application of KIO3. In addition, the calculated hazard quotient values indicate that the iodine content of kale was safe for the consumer. The obtained results showed that the chemical composition of kale was more influenced by the cultivar of kale than by the used iodine compound. Kale is a natural source of many bioactive compounds, and the application of iodoquinolines has the potential to further enhance its health-promoting properties. In this study, we present that the treatment with iodoquinolines is a promising new method for biofortification of kale grown in a hydroponic system with iodine. In the future, this novel approach to increasing the iodine content of leafy vegetables could be an important aspect of worldwide iodine prevention. [Display omitted]