| Popis: |
Innovative agricultural practices are increasingly focused on conserving resources, reducing negative environmental impacts, and producing food with high nutritional quality and high content of health-promoting phytonutrients. Proper selection of cultivating factors, especially balanced nutrition, can significantly increase nutritional value and result in foods with significant biological and functional properties. The innovative techniques for cultivation of plant species, such as floating hydroponic systems, can also ensure a uniform chemical composition and high specialized metabolites (SM) content through nutrient solution management. Although it has been neglected in human diet, stinging nettle has a rich chemical composition (vitamins, minerals, pigments, phenols and other SM) and can be consumed as a green leafy vegetable. The aim of this study was to determine the influence of different corrections (B1, B2 and B3) of the nutrient solution (NS) during three harvest periods on the SM content and antioxidant capacity of nettle leaves. The B1 and B2 treatments were initially filled with NS prepared independently of the water’s chemical composition and B3 was filled with NS adjusted according to the chemical analysis of the water. After each harvest, the corrections of NS were made as follows: B1 was filled with water, B2 with NS, and B3 with nutrients according to the chemical analysis of NS. Of the nutritional and functional properties, total phenolics (TP), ascorbic acid (AsA), pigment content and antioxidant capacity were analyzed. The highest TP (377.04 mg GAE/100 g), total flavonoid (279.54 mg CTH/100 g), AsA (112.37 mg/100 g) and pigment content, as well as the highest antioxidant capacity (3546.91 µmol TE/L) were recorded in the third harvest, B2 treatment. The results show a significant positive influence of multiple harvesting and NS treatment on the SM content of nettle, confirming this type of hydroponic cultivation as an innovative technique for the production of novel food with high nutritional value. |
