| Abstract [eng] |
Broccoli (Brassica oleracea var. italica) is one of the most common cruciferous vegetables in the use worldwide, with antioxidant, anti-inflammatory, antimicrobial and neuroprotective properties. Due to its nutritional and health potential, it is common to use broccoli florets and sprouts for food, while the stems and leaves are waste at harvest. However, these under-utilised parts of the vegetable can also be used as functional food sources contributing to the prevention and treatment of certain chronic disorders. Phytohormones that regulate plant growth, development and cell differentiation and division are used to improve and ensure the desired concentrations of secondary metabolites synthesised by broccoli in laboratory methods. In this study, broccoli (Brassica oleracea var. italica) callus cultures were established in vitro, which differed in the composition of the nutrient media. Auxins (2,4-D) and cytokinins (BAP) together with amino acids (L-methionine and L-tryptophan) were used to supplement the nutrient media. After in vitro broccoli callus cultures were established, their antioxidant activity was assessed by different methods. The DPPH, ABTS and FRAP methods showed that supplementation of broccoli leaf, root and stem MS nutrient media with BAP (2 mg/l) and 2,4-D (0.2 mg/l) and L-methionine (100 µM) was the most effective in promoting the antioxidant properties. The evaluation of superoxide dismutase showed that the most significant activity of this enzyme in leaf and stem callus cultures was due to the addition of growth hormones BAP (2 mg/l) and 2,4-D (0.2 mg/l) to MS medium. The method for the evaluation of pigments showed that broccoli accumulates mainly carotenoids, and that the highest concentrations of carotenoids, especially in leaf callus culture, were due to the addition of amino acids to the nutrient media. The greatest effect on glucosinolate synthesis in differentiated broccoli tissues was due to the addition of L-methionine to MS medium. The concentrations of malondialdehyde, phenolic compounds and acids, proteins, flavonoids, L-proline and reduced glutathione were also evaluated in this study. A technological scheme for the extraction of glucosinolates from broccoli callus cultures was proposed. |
