The Influence of Phytohormones on Antioxidative and Antibacterial Activities in Callus Cultures of Hypericum perforatum L.

Natural extracts of Hypericum perforatum L. are widely used in the pharmaceutical industry due to their antiviral, antioxidant, antibacterial, antidiabetic, and antidepressant activities. Plant biotechnological methods are gaining more attention as efficient and biosustainable approaches for the production of high value compounds by using plant callus cultures in vitro. The aim of this research was to evaluate the influence of phytohormones on the formation of Hypericum perforatum L. callus culture, to explore antioxidant and antibacterial activities, and to determine the amounts of phytochemicals in the analyzed extracts. Callus cultures were induced on Murashige and Skoog basal medium supplemented with phytohormones (auxins, cytokinins, and salicylic acid), and containing newly synthesized compound N-(1,3-dioxoisoindolin-2-yl)-3-((4-methoxyphenyl)amino)propanamide. The antioxidant activities of callus cultures were evaluated using DPPH and FRAP assays and the enzyme antioxidants (superoxide dismutase, catalase, and ascorbate peroxidase) were evaluated. The antibacterial activity of plant extracts was screened against Escherichia coli and Bacillus subtilis bacteria by the diffusion agar method. There was a significant positive correlation between total phenolic content and high antioxidant efficiency in Hypericum perforatum L. callus cultures, which were formed on Murashige and Skoog medium supplemented with auxin, cytokinin, and salicylic acid (100 µM). Our results have demonstrated that callus cultures generated on MS medium supplemented with N-(1,3-dioxoisoindolin-2-yl)-3-((4-methoxyphenyl)amino)propanamide and cytokinin BAP (0.5 mg L⁻¹) exhibited improved antioxidant activities for the first time.