Hypericum perforatum, commonly known as St John's wort, is a flowering plant in the family Hypericaceae. It is a perennial plant that grows up to one meter tall, with many yellow flowers that have clearly visible black glands around their edges, long stamens, and three pistils. Probably a hybrid between the closely related H. attenuatum and H. maculatum that originated in Siberia, the species is now found worldwide. It is native to temperate regions across Eurasia and North Africa, and has been introduced to East Asia, Australia, New Zealand, and parts of North and South America. In many areas where it is not native, H. perforatum is considered a noxious weed. It densely covers open areas to the exclusion of native plants, and is poor grazing material. As such, methods for biocontrol have been introduced in an attempt to slow or reverse the spread of the species.
Hypericum is a genus of flowering plants in the family Hypericaceae. The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar regions. Many Hypericum species are regarded as invasive species and noxious weeds. All members of the genus may be referred to as St. John's wort, and some are known as goatweed. The white or pink flowered marsh St. John's worts of North America and eastern Asia are generally accepted as belonging to the separate genus TriadenumRaf.
Hypericum calycinum is a species of prostrate or low-growing shrub in the flowering plant family Hypericaceae. Widely cultivated for its large yellow flowers, its names as a garden plant include rose-of-Sharon in Britain and Australia, and Aaron's beard, great St-John's wort, creeping St. John's wort and Jerusalem star. Grown in Mediterranean climates, widely spread in the Strandzha Mountains along the Bulgarian and Turkish Black Sea coast.
Hyperforin is a phytochemical produced by some of the members of the plant genus Hypericum, notably Hypericum perforatum. Hyperforin may be involved in the pharmacological effects of St. John's wort, specifically in its antidepressant effects.
In organic chemistry, polyketides are a class of natural products derived from a precursor molecule consisting of a chain of alternating ketone and methylene groups: [−C(=O)−CH2−]n. First studied in the early 20th century, discovery, biosynthesis, and application of polyketides has evolved. It is a large and diverse group of secondary metabolites caused by its complex biosynthesis which resembles that of fatty acid synthesis. Because of this diversity, polyketides can have various medicinal, agricultural, and industrial applications. Many polyketides are medicinal or exhibit acute toxicity. Biotechnology has enabled discovery of more naturally-occurring polyketides and evolution of new polyketides with novel or improved bioactivity.
Dimethylallyl pyrophosphate is an isoprenoid precursor. It is a product of both the mevalonate pathway and the MEP pathway of isoprenoid precursor biosynthesis. It is an isomer of isopentenyl pyrophosphate (IPP) and exists in virtually all life forms. The enzyme isopentenyl pyrophosphate isomerase catalyzes isomerization between DMAPP and IPP.
Okadaic acid, C44H68O13, is a toxin produced by several species of dinoflagellates, and is known to accumulate in both marine sponges and shellfish. One of the primary causes of diarrhetic shellfish poisoning, okadaic acid is a potent inhibitor of specific protein phosphatases and is known to have a variety of negative effects on cells. A polyketide, polyether derivative of a C38 fatty acid, okadaic acid and other members of its family have shined light upon many biological processes both with respect to dinoflagellete polyketide synthesis as well as the role of protein phosphatases in cell growth.
Dopaminergic means "related to dopamine", a common neurotransmitter. Dopaminergic substances or actions increase dopamine-related activity in the brain.
Epothilones are a class of potential cancer drugs. Like taxanes, they prevent cancer cells from dividing by interfering with tubulin, but in early trials, epothilones have better efficacy and milder adverse effects than taxanes.
An antileukotriene, also known as leukotriene modifier and leukotriene receptor antagonist, is a medication which functions as a leukotriene-related enzyme inhibitor or leukotriene receptor antagonist and consequently opposes the function of these inflammatory mediators; leukotrienes are produced by the immune system and serve to promote bronchoconstriction, inflammation, microvascular permeability, and mucus secretion in asthma and COPD. Leukotriene receptor antagonists are sometimes colloquially referred to as leukasts.
Arachidonate 5-lipoxygenase inhibitors are compounds that slow or stop the action of the arachidonate 5-lipoxygenase enzyme, which is responsible for the production of inflammatory leukotrienes. The overproduction of leukotrienes is a major cause of inflammation in asthma, allergic rhinitis, and osteoarthritis.
Monoamine oxidase B, also known as MAO-B, is an enzyme that in humans is encoded by the MAOB gene.
Reuptake inhibitors (RIs) are a type of reuptake modulators. It is a drug that inhibits the plasmalemmal transporter-mediated reuptake of a neurotransmitter from the synapse into the pre-synaptic neuron. This leads to an increase in extracellular concentrations of the neurotransmitter and an increase in neurotransmission. Various drugs exert their psychological and physiological effects through reuptake inhibition, including many antidepressants and psychostimulants.
Streptogramin A is a group of antibiotics within the larger family of antibiotics known as streptogramins. They are synthesized by the bacteria Streptomyces virginiae. The streptogramin family of antibiotics consists of two distinct groups: group A antibiotics contain a 23-membered unsaturated ring with lactone and peptide bonds while group B antibiotics are depsipeptides. While structurally different, these two groups of antibiotics act synergistically, providing greater antibiotic activity than the combined activity of the separate components. These antibiotics have until recently been commercially manufactured as feed additives in agriculture, although today there is increased interest in their ability to combat antibiotic-resistant bacteria, particularly vancomycin-resistant bacteria.
Hypericum olympicum, commonly known as the Mount Olympus St. John's wort, is a species of flowering plant in the family Hypericaceae found in the Balkans and Turkey and introduced to western Europe. It has been widely cultivated for centuries because of its large, showy flowers, which are far larger than those of most other species in Hypericum.
Amentoflavone is a biflavonoid constituent of a number of plants including Ginkgo biloba, Chamaecyparis obtusa (hinoki), Biophytum sensitivum, Selaginella tamariscina, Hypericum perforatum and Xerophyta plicata.
Callystatin A is a polyketide natural product from the leptomycin family of secondary metabolites. It was first isolated in 1997 from the marine sponge Callyspongia truncata which was collected from the Goto Islands in the Nagasaki Prefecture of Japan by the Kobayashi group. Since then its absolute configuration has been elucidated and callystatin A was discovered to have anti-fungal and anti-tumor activities with extreme potency against the human epidermoid carcinoma KB cells (IG50 = 10 pg/ml) and the mouse lymphocytic leukemia Ll210 cells (IG50 = 20 pg/ml).
Atrop-abyssomicin C is a polycyclic polyketide-type natural product that is the atropisomer of abyssomicin C. It is a spirotetronate that belongs to the class of tetronate antibiotics, which includes compounds such as tetronomycin, agglomerin, and chlorothricin. In 2006, the Nicolaou group discovered atrop-abyssomicin C while working on the total synthesis of abyssomicin C. Then in 2007, Süssmuth and co-workers isolated atrop-abyssomicin C from Verrucosispora maris AB-18-032, a marine actinomycete found in sediment of the Japanese sea. They found that atrop-abyssomicin C was the major metabolite produced by this strain, while abyssomicin C was a minor product. The molecule displays antibacterial activity by inhibiting the enzyme PabB, thereby depleting the biosynthesis of p-aminobenzoate.
Hypericum bupleuroides is a species of perennial flowering plant in the St John's wort family, Hypericaceae. It grows 45–80 centimeters tall, and notably has perfoliate leaves that are fused at the stem. It has pyramid-shaped flower clusters of 1 to 25 flowers with yellow petals in a star-shaped arrangement. The species is found along the Black Sea coast near the Turkish–Georgian border. Hypericum bupleuroides has a small distribution and specific habitat requirements that make it vulnerable to environmental pressures.
Pseudohypericin is an aromatic polycyclic dione that is very closely related to hypericin. It is found most commonly in the St. John's wort family of plants, namely in Hypericum perforatum. In preliminary studies in animal models, pseudohypericin has shown antiviral effects. It may also contribute to the potential antidepressant effect of Hypericum perforatum extracts.
