Serotonin or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vasoconstriction.
Tryptophan is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic beta carbon substituent. It is essential in humans, meaning that the body cannot synthesize it and it must be obtained from the diet. Tryptophan is also a precursor to the neurotransmitter serotonin, the hormone melatonin, and vitamin B3. It is encoded by the codon UGG.
Melatonin is a natural product found in plants and animals. It is primarily known in animals as a hormone released by the pineal gland in the brain at night, and has long been associated with control of the sleep–wake cycle.
Flavan-3-ols are a subgroup of flavonoids. They are derivatives of flavans that possess a 2-phenyl-3,4-dihydro-2H-chromen-3-ol skeleton. Flavan-3-ols are structurally diverse and include a range of compounds, such as catechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, proanthocyanidins, theaflavins, thearubigins. They are found in most plants and have a role in plant defense.
Tryptamine is an indolamine metabolite of the essential amino acid, tryptophan. The chemical structure is defined by an indole ─ a fused benzene and pyrrole ring, and a 2-aminoethyl group at the second carbon (third aromatic atom, with the first one being the heterocyclic nitrogen). The structure of tryptamine is a shared feature of certain aminergic neuromodulators including melatonin, serotonin, bufotenin and psychedelic derivatives such as dimethyltryptamine (DMT), psilocybin, psilocin and others. Tryptamine has been shown to activate trace amine-associated receptors expressed in the mammalian brain, and regulates the activity of dopaminergic, serotonergic and glutamatergic systems. In the human gut, symbiotic bacteria convert dietary tryptophan to tryptamine, which activates 5-HT4 receptors and regulates gastrointestinal motility. Multiple tryptamine-derived drugs have been developed to treat migraines, while trace amine-associated receptors are being explored as a potential treatment target for neuropsychiatric disorders.
Aromatic L-amino acid decarboxylase, also known as DOPA decarboxylase (DDC), tryptophan decarboxylase, and 5-hydroxytryptophan decarboxylase, is a lyase enzyme, located in region 7p12.2-p12.1.
Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids.
Harmine is a beta-carboline and a harmala alkaloid. It occurs in a number of different plants, most notably the Syrian rue and Banisteriopsis caapi. Harmine reversibly inhibits monoamine oxidase A (MAO-A), an enzyme which breaks down monoamines, making it a Reversible inhibitor of monoamine oxidase A (RIMA). Harmine does not inhibit MAO-B. Harmine is also known as banisterin, banisterine, telopathin, telepathine, leucoharmine and yagin, yageine.
Indole-3-acetic acid is the most common naturally occurring plant hormone of the auxin class. It is the best known of the auxins, and has been the subject of extensive studies by plant physiologists. IAA is a derivative of indole, containing a carboxymethyl substituent. It is a colorless solid that is soluble in polar organic solvents.
Gingerol, properly as [6]-gingerol, is a phenol phytochemical compound found in fresh ginger that activates spice receptors on the tongue. Molecularly, gingerol is a relative of capsaicin and piperine, the compounds which are alkaloids, though the bioactive pathways are unconnected. It is normally found as a pungent yellow oil in the ginger rhizome, but can also form a low-melting crystalline solid. This chemical compound is found in all members of the Zingiberaceae family and is high in concentrations in the grains of paradise as well as an African Ginger species.
Caffeic acid is an organic compound that is classified as a hydroxycinnamic acid. This yellow solid consists of both phenolic and acrylic functional groups. It is found in all plants because it is an intermediate in the biosynthesis of lignin, one of the principal components of woody plant biomass and its residues.
p-Coumaric acid is an organic compound with the formula HOC6H4CH=CHCO2H. It is one of the three isomers of hydroxycinnamic acid. It is a white solid that is only slightly soluble in water but very soluble in ethanol and diethyl ether.
Tryptophan hydroxylase (TPH) is an enzyme (EC 1.14.16.4) involved in the synthesis of the neurotransmitter serotonin. Tyrosine hydroxylase, phenylalanine hydroxylase, and tryptophan hydroxylase together constitute the family of biopterin-dependent aromatic amino acid hydroxylases. TPH catalyzes the following chemical reaction
An aromatic amino acid is an amino acid that includes an aromatic ring.
Cinnamoyl-CoA reductase (EC 1.2.1.44), systematically named cinnamaldehyde:NADP+ oxidoreductase (CoA-cinnamoylating) but commonly referred to by the acronym CCR, is an enzyme that catalyzes the reduction of a substituted cinnamoyl-CoA to its corresponding cinnamaldehyde, utilizing NADPH and H+ and releasing free CoA and NADP+ in the process. Common biologically relevant cinnamoyl-CoA substrates for CCR include p-coumaroyl-CoA and feruloyl-CoA, which are converted into p-coumaraldehyde and coniferaldehyde, respectively, though most CCRs show activity toward a variety of other substituted cinnamoyl-CoA's as well. Catalyzing the first committed step in monolignol biosynthesis, this enzyme plays a critical role in lignin formation, a process important in plants both for structural development and defense response.
Tryptophan hydroxylase 1 (TPH1) is an isoenzyme of tryptophan hydroxylase which in humans is encoded by the TPH1 gene.
Fenclonine, also known as para-chlorophenylalanine (PCPA), acts as a selective and irreversible inhibitor of tryptophan hydroxylase, which is a rate-limiting enzyme in the biosynthesis of serotonin.
Anthocyanins are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical compound that gives flowers a blue color for the first time in his treatise “Die Farben der Blüthen”. Food plants rich in anthocyanins include the blueberry, raspberry, black rice, and black soybean, among many others that are red, blue, purple, or black. Some of the colors of autumn leaves are derived from anthocyanins.
Fisetin (7,3′,4′-flavon-3-ol) is a plant flavonol from the flavonoid group of polyphenols. It can be found in many plants, where it serves as a yellow/ochre colouring agent. It is also found in many fruits and vegetables, such as strawberries, apples, persimmons, onions and cucumbers. Its chemical formula was first described by Austrian chemist Josef Herzig in 1891.
Curcumin synthase categorizes three enzyme isoforms, type III polyketide synthases (PKSs) present in the leaves and rhizome of the turmeric plant that synthesize curcumin. CURS1-3 are responsible for the hydrolysis of feruloyldiketide-CoA, previously produced in the curcuminoid pathway, and a decarboxylative condensation reaction that together comprise one of the final steps in the synthesis pathway for curcumin, demethoxycurcumin, and bisdemethoxycurcumin, the compounds that give turmeric both its distinctive yellow color, and traditional medical benefits. CURS should not be confused with Curcuminoid Synthase (CUS), which catalyzes the one-pot synthesis of bisdemethoxycurcumin in Oryza sativa.
