| Abstract [eng] |
Plants of the Asteraceae family – marigold (Calendula officinalis L.), tarragon (Artemisia dracunculus L.) and echinacea (Echinacea purpurea L.) – have long been among the most popular medicinal plants that are widely used in the pharmaceutical, cosmetic and food industries. These plants have antioxidant, antibacterial and anticancer properties. These beneficial biological properties of medicinal plants are determined by their synthesized secondary metabolites. Due to the bioactive compounds present in astral plant extracts, these plants can be used to synthesize silver nanoparticles by green synthesis. In order to increase the synthesis of bioactive substances in callus cultures of calendula, sedum and echinacea in vitro, the nutrient medium was enriched with growth regulators. The main objective of this study was to evaluate the effect of selected growth regulators on the antioxidant, antibacterial and phytochemical activity of in vitro extracts of callus cultures of aster plants. During the project, in vitro callus cultures of marigold, tarragon and echinacea were formed, which were grown in MS medium supplemented with growth hormones. The extract of medicinal tarragon in vitro grown with BAP (2.5 mg/l) and NAA (0.5 mg/l) growth hormones showed the highest antioxidant activity. During the study, it was found that the selected growth hormones effectively increased the activity of proline dehydrogenase in callus cultures of tarragon (53.1%), echinacea (27.1%) and marigold (67%) and the activity of other antioxidant enzymes. The highest concentrations of chlorophyll a (13.11 mg/100 mg), chlorophyll b (18.92 mg/100 mg), carotenoids (6.17 mg/100 mg) and proteins (0.53 mg/100 mg) were found in echinacea in vitro extract. Selected growth hormones negatively affected the synthesis of anthocyanins and flavonoids in marigold and echinacea callus cultures in vitro. Nutrient medium supplementation effectively increased the synthesis of phenolic compounds in callus cultures of tarragon (44.2%), echinacea (62.3%) and marigold (48.24%) in vitro. The highest concentration of L-proline (25.17 mmol/g) and phenolic acids (5.02%) was determined in the in vitro extract of medicinal tarragon. The highest antibacterial activity against Escherichia coli was demonstrated by the in vitro extract of echinacea callus cultures (19.67 mm), and against Bacillus subtilis by the in vitro extract of marigold (15.17 mm). Silver nanoparticles were mainly synthesized from the in vitro extract of the medicinal tarragon. Marigold in vitro showed the best antioxidant properties according to the DPPH method (31.76%), and colloidal solutions with silver nanoparticles in vitro of echinacea (0.32 A) according to the reduction properties evaluation. Colloidal solutions with silver nanoparticles showed the highest antibacterial activity against Escherichia coli in vitro of tarragon (22.80 mm), and against Bacillus subtilis in vitro of marigold (18.50 mm). |
