Chemical Composition and Histochemical Localization of Essential Oil from Wild and Cultivated Rhaponticum carthamoides Roots and Rhizomes.

Rhaponticum carthamoides (Willd.) Iljin is not only a source of phytosteroids and flavonoids, but is also source of essential oil (EO). This study evaluated the volatile metabolic constituents and histochemical localization of root and rhizome essential oils (EOs) from R. carthamoides populations wild-grown in Russia and cultivated in Bulgaria. The performed histochemical analysis confirmed the presence of lipophilic substances in the secretory ducts of the examined roots and rhizomes. Both EOs were obtained by hydrodistillation and further analyzed by gas chromatography with mass detection. The results showed differences between the chemical compositions of both EOs. Forty-six components were tentatively identified in R. carthamoides oil from the wild population, with ß-selinene (4.77%), estragole (6.32%), D-carvone (6.37%), cyperene (8.78%), and ledene oxide (11.52%) being the major constituents. In the EO isolated from cultivated R. carthamoides, twenty-three compounds were tentatively identified, with humulene (7.68%), ß-elemene (10.76%), humulene-1,2-epoxide (11.55%), ledene oxide (13.50%), and δ-elemene (19.08%) predominating. This is the first report describing the histolocalization and chemical profile of EO from R. carthamoides cultivated in Bulgaria. Further research on the cultivation of R. carthamoides in Bulgaria would affect the relationship between its chemical composition and pharmacological effects.

Polysaccharides and Their Derivatives as Potential Antiviral Molecules.

In the current context of the COVID-19 pandemic, it appears that our scientific resources and the medical community are not sufficiently developed to combat rapid viral spread all over the world. A number of viruses causing epidemics have already disseminated across the world in the last few years, such as the dengue or chinkungunya virus, the Ebola virus, and other coronavirus families such as Middle East respiratory syndrome (MERS-CoV) and severe acute respiratory syndrome (SARS-CoV). The outbreaks of these infectious diseases have demonstrated the difficulty of treating an epidemic before the creation of vaccine. Different antiviral drugs already exist. However, several of them cause side effects or have lost their efficiency because of virus mutations. It is essential to develop new antiviral strategies, but ones that rely on more natural compounds to decrease the secondary effects. Polysaccharides, which have come to be known in recent years for their medicinal properties, including antiviral activities, are an excellent alternative. They are essential for the metabolism of plants, microorganisms, and animals, and are directly extractible. Polysaccharides have attracted more and more attention due to their therapeutic properties, low toxicity, and availability, and seem to be attractive candidates as antiviral drugs of tomorrow.

Plant-Based Diet as a Strategy for Weight Control.

According to the World Health Organization, obesity has nearly tripled since the 1970s. Obesity and overweight are major risk factors for cardiovascular diseases, diabetes, inflammatory-mediated diseases, and other serious medical conditions. Moreover, recent data suggest that obesity, overweight, diabetes, and cardiovascular diseases are risk factors for COVID-19-related mortality. Different strategies for weight control have been introduced over the last two decades. Unfortunately, these strategies have shown little effect. At the same time, many studies show that plants might be the key to a successful strategy for weight control. Following the PRISMA guidelines for conducting systematic reviews, a search was conducted in PubMed, Web of Science, Scopus, and Embase using the following keywords: obesity, globesity, vegan, plant-based diet, etc. Our results show that vegan diets are associated with improved gut microbiota symbiosis, increased insulin sensitivity, activation of peroxisome proliferator-activated receptors, and over-expression of mitochondrial uncoupling proteins. The key features of this diet are reduced calorie density and reduced cholesterol intake. The combination of these two factors is the essence of the efficiency of this approach to weight control. Our data suggest that plant-based/vegan diets might play a significant role in future strategies for reducing body weight.

Plant Adaptogens-History and Future Perspectives.

Adaptogens are synthetic compounds (bromantane, levamisole, aphobazole, bemethyl, etc.) or plant extracts that have the ability to enhance the body's stability against physical loads without increasing oxygen consumption. Extracts from Panax ginseng, Eleutherococcus senticosus, Rhaponticum carthamoides, Rhodiola rosea, and Schisandra chinensis are considered to be naturally occurring adaptogens and, in particular, plant adaptogens. The aim of this study is to evaluate the use of plant adaptogens in the past and now, as well as to outline the prospects of their future applications. The use of natural adaptogens by humans has a rich history-they are used in recovery from illness, physical weakness, memory impairment, and other conditions. About 50 years ago, plant adaptogens were first used in professional sports due to their high potential to increase the body's resistance to stress and to improve physical endurance. Although now many people take plant adaptogens, the clinical trials on human are limited. The data from the meta-analysis showed that plant adaptogens could provide a number of benefits in the treatment of chronic fatigue, cognitive impairment, and immune protection. In the future, there is great potential to register medicinal products that contain plant adaptogens for therapeutic purposes.