Phytochemistry and Plant Biology

Saponins is a class of chemical compounds, one of many secondary metabolites found in natural sources with saponins found in particular abundance in various plant species. Specifically, these are amphipathic glycosides grouped phenomenologically by the soap-like foaming they produce when shaken in aqueous solutions.

Ergosterol is a biological precursor (a provitamin) to vitamin D₂. It is turned into viosterol by ultraviolet light and is then converted into ergocalciferol which is a form of vitamin D. It does not occur in plants or animal cells, but it is a component of yeast and fungal cell membranes serving the same function that cholesterol serves in animal cells.

Lycopene is a bright red carotene and carotenoid pigment and phytochemical found in tomatoes and other red fruits and vegetables, such as red carrots, watermelons and papayas (but not strawberries or cherries).

Ecology is the scientific study of the relationship that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount (biomass), number, and changing states of organisms within and among ecosystems.

Astaxanthin is a carotenoid. It belongs to a larger class of phytochemicals known as terpenes. It is classified as a xanthophyll, which means yellow leaves. Like many carotenoids, it is a colourful, lipid-soluble pigment.

Vitamin E, including tocotrienol and tocopherol, is fat soluble and protects lipids. Sources include wheat germ, seabuckthorn, nuts, seeds, whole grains, green leafy vegetables, kiwifruit, vegetable oil, and fish-liver oil. Alpha-tocopherol is the main form in which vitamin E is consumed. Recent studies showed that some tocotrienol isomers have significant anti-oxidant properties.

Proanthocyanidin is a class of flavanols. Proanthocyanidins are essentially polymer chains of flavonoids such as catechins.

Hesperetin is a bioflavonoid. It is water-soluble due to the presence of the sugar part in its structure, so on ingestion it releases its aglycone, i.e, hesperetin. Hesperidin is found in Citrus fruits.

Oenin is an anthocyanin. It is the 3-glucoside of malvidin. It can be found in the skin of purple grapes and in wine.

A glycoside is a molecule in which one or more sugar molecules is bound to a non-carbohydrate moiety, usually a small organic molecule. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides.

Thearubigins are polymeric polyphenols that are formed during the enzymatic oxidation (called fermentation by the tea trade) of tea leaves. Thearubigins are red in colour. Therefore, a black (fully oxidized) tea gives a reddish liquor while a green or white tea gives a much clearer one.

Pelargonidin is an anthocyanidin, a type of plant pigment. Like all anthocyanins, it is an antioxidant. It produces a characteristic orange colour, and can be found in red geraniums, and ripe raspberries and strawberries, as well as blueberries, blackberries, plums and cranberries and pomegranates.

Heliotropism is the diurnal motion of plant parts (flowers or leaves) in response to the direction of the sun.

Thigmotropism is a movement in which an organism moves or grows in response to touch or contact stimuli. Usually thigmotropism occurs when plants grow around a surface, such as a wall, pot, or trellis.

Rheotaxis is a response to a current in a fluid. Positive rheotaxis is shown by fish turning to face against the current. In a flowing stream, this behaviour leads them to hold their position in a stream rather than being swept downstream. Some fish will exhibit negative rheotaxis where they will avoid currents.

Aerotaxis is the response of an organism to variation in oxygen concentration, and is mainly found in aerobic bacteria.

Phonotaxis is the movement of an organism in response to sound.

Cichoric acid is a hydroxycinnamic acid, an organic compound of the phenylpropanoid class and occurs in a variety of plant species. It is a derivative of both the caffeic acid and tartaric acid.

Phospholipases are enzymes that release fatty acids from the second carbon group of glycerol. This particular phospholipase specifically recognizes the sn-2 acyl bond of phospholipids and catalytically hydrolyzes the bond releasing arachidonic acid and lysophospholipids.

Serotonin is a monoamine neurotransmitter. Biochemically derived from tryptophan, serotonin is primarily found in the gastrointestinal (GI) tract, platelets, and in the central nervous system (CNS) of animals including humans. It is a well-known contributor to feelings of well-being; therefore it is also known as a happiness hormone despite not being a hormone.

A fibrocyte is an inactive mesenchymal cell, that is, a cell showing minimal cytoplasm, limited amounts of rough endoplasmic reticulum and lacks biochemical evidence of protein synthesis.

Glycitein is an O-methylated isoflavone which accounts for 5-10% of the total isoflavones in soy food products. Glycitein is a phytoestrogen with weak estrogenic activity, comparable to that of the other soy isoflavones.

Cytokinins (CK) are a class of plant growth substances (plant hormones) that promote cell division, or cytokinesis, in plant roots and shoots. These are primarily involved in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and leaf senescence.

A gallotannin is a class of molecules belonging to the hydrolysable tannins. Gallotannins are polymers formed when gallic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose.

Thromboxane is a member of the family of lipids known as eicosanoids. The two major thromboxanes are thromboxane A2 and thromboxane B2. The distinguishing feature of thromboxanes is a 6-membered ether-containing ring.