Biotechnological Potential of Different Organs of Mistletoe (Viscum album L.) Collected from Various Host Tree Species in an Urban Area

The cardioprotective potential of selected species of mistletoe

Mistletoe is an evergreen woody shrub with stems measuring 30-100 cm. It has leathery, yellowish-green strap-shaped leaves, yellowish-green flowers, and bears typical berries. The most common species is Viscum album L., mainly present in Europe and Asia. It is commonly known as European mistletoe or simply, mistletoe. Scientific interest in mistletoe was awakened in the XX century. Mistletoe, especially V. album L., has historically been used in the treatment and prophylaxis of CVD, with its properties being confirmed in recent studies. This mini-review describes new aspects of the cardioprotective properties of various species of mistletoe, especially V. album L. The effect of oral and subcutaneous application of fresh V. album L. extracts on blood pressure has been studied in various models; while the data suggests that mistletoe may be a promising herbal extract with cardioprotective properties, the species has only been tested in vitro and in vivo, on animals. In addition, it is unclear whether the cardioprotective activity of mistletoe may be due to particular chemical components, as the chemical composition of mistletoe extracts can vary depending on inter alia the time of harvest, extraction method and plant part. Hence, this activity may instead result from synergistic interactions between various secondary metabolites. Therefore, further studies are needed to identify the mechanisms of action of mistletoe compounds on CVDs, and determine their interactions with other cardioprotective drugs, their metabolic mechanisms, pharamacokinetics and adverse effects. More research is also needed to determine the therapeutic doses of active ingredients for use in clinical trials; this would require an accurate understanding of the chemical composition of extracts from different species of mistletoe (not only V. album L.) and from various host trees.

Effect of Salinity Stress on Phenolic Compounds and Antioxidant Activity in Halophytes Spergularia marina (L.) Griseb. and Glaux maritima L. Cultured In Vitro

The study of halophytes as sources of phenolic compounds, as well as conditions that further enhance the accumulation of biologically active compounds in them, is of particular interest. In this paper, the effect of different salinity levels (25-500 mM in the form of NaCl) on the content of phenolic compounds and the antioxidant activity of two rare halophyte species Spergularia marina (L.) Griseb. and Glaux maritima L. cultured in vitro was investigated. A species-specific reaction of plants to salinization was established. In G. maritima, the maximum total content of phenolic compounds was observed at 50-100 mM, flavonoids 75-400 mM, and hydroxycinnamic acids 200-300 mM, as well as individual phenolics (protocatechuic acid, catechin, astragalin, hyperoside, rutin, isoquercitrin, and apigenin derivative) at 100-300 mM NaCl. For S. marina, on the contrary, there was a slight decrease in the content of phenolic compounds when NaCl was added to the nutrient medium compared to the control. The content of protocatechuic acid, rosmarinic acid, and apigenin derivative significantly decreased with increased salt stress. The change in antioxidant activity at different salinity levels was also species specific. The maximum values of different groups of phenolic compounds in G. maritima were observed at 50-300 mM NaCl. The cultivation of S. marina without the addition of NaCl and at 500 mM NaCl allowed the production of plants with the highest content of phenolic compounds. The obtained results can be further used in the development of protocols for the cultivation of these plants in vitro in order to induce the biosynthesis of phenolic compounds in them.