Knotweeds (Reynoutria Houtt.) are plants native to the Far East. Japanese knotweed was introduced from Japan to the unsuspecting West by the horticultural activities of Philippe von Siebold via his nursery at Leiden in the 1840s. By 1854, the plant had arrived at the Royal Botanic Gardens in Edinburgh. The plants were then sold by a large number of commercial nursery gardens around the country. Further vegetative spread followed naturally along watercourses. The knotweed is currently extremely persistant invasive plant. There is also an important source of many bioactive substances which could be used in biomedicine. The article discusses biomedically relevant constituents and its pharmacological and toxicological properties.

The paper deals with Lilium candidum L., a well-known ancient plant in folk medicine for the treatment of burns, ulcers, inflammations and wound healing. The petals and bulbs of this plant contain many bioactive compounds. Many of them could also find their place in modern medicine.

The ongoing coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global health crisis. Flavon baicalein, a major bioactive molecule of Scutellaria baicalensis, inhibits the replication of SARS-CoV-2 which causes severe acute respiratory syndrome in humans. Animal experiments show that baicalein has the character of a broad-spectrum coronavirus drug. It is non-toxic and can inhibit SARS-CoV-2-induced damage. Baicalein may therefore be a promising therapeutic drug for the treatment of COVID-19.

Diabetes mellitus je chronické metabolické onemocnění projevující se hyperglykemií. V současnosti představuje ve světě jednu z nějčastějších zdravotních komplikací a jeho incidence stále stoupá. Hyperglykemie je způsobena sníženou či chybějící sekrecí inzulinu nebo rezistencí periferních tkání k jeho účinku. Nekompenzovaný diabetes a hyperglykemie přinášejí řadu dalších komplikací, jako je retinopatie, nefropatie, kardiovaskulární onemocnění a další. Prediabetes je stav, který často přechází v diabetes mellitus a projevuje se zvýšenou hladinou glukózy v krvi či narušenou glukózovou tolerancí. V případě prediabetu a diabetu 2. typu je možné kromě standardní terapie dietou a perorálními antidiabetiky či inzulinem použít i fytoterapii. Existuje řada rostlin i hub s antidiabetickým účinkem a účinky některých z nich již podpořily i klinické studie. Tento souhrnný článek představuje čtyři druhy rostlin a hub s antidiabetickým účinkem: hnojník obecný (Coprinus comatus), skořicovník (Cinnamomum spp.), chebuli srdčitou (Tinospora cordata) a zázvor lékařský (Zingiber officinale), které je možné užívat ve formě doplňků stravy.

v Praze, katedra botaniky 2 Jihočeská univerzita v Českých Budějovicích, Zdravotně sociální fakulta, katedra radiologie a toxikologie Summary The annual wormwood (Artemisia annua L.) is a plant from the family Asteraceae. It comes from China, where it is an important part of the traditional Chinese medicine. Terpenoids (particularly sesquiterpenic lactones), flavonoids, coumarins and other metabolites of shikimic acid are the prevalent substances in the species A. annua, as is also the case in many other species of the genus Artemisia. The most important substance is biologically active sesquiterpene artemisinine (Qinghaosu). Artemisinine, sesquiterpenic lactone with endoperoxide bond, found in above-ground parts of A. annua, is more effective, more rapid and less toxic in the treatment of malaria compared to chloroquine. Malaria is currently the most severe infectious disease worldwide with at least 300 million reported cases annually. The annual wormwood is the main natural botanical source of artemisinine and potential source of essential oil for the manufacture of perfumes. Contents of artemisinine are very dependent on the plant ecotype, ecological conditions and seasonal and geographical variations. The annual wormwood is currently cultivated in China, Vietnam, India, Romania, Kenya and Tanzania. Methods of the chemical and biological synthesis of artemisinine are ever being studied due to poor yields from natural sources, but the natural or cultivated forms of A. annua are still the main sources of this substance. The medicinal value of artemisinine is unfortunately limited due to its low solubility in both oil and water, which resulted in developing semi-synthetic derivatives exerting pharmacological characteristics superior to those of the original substance. The most important derivatives of this type are artemether, arteether and artesunate, which exert higher efficacy and also higher solubility and metabolic and hydrolytic stability compared to artemisinine. In addition, artemisinine and its semisynthetic derivatives are characterized by their strong anti-cancer activity, antibacterial effects and by possibility of their use as pesticides.