Chemical Properties
Off-White to Light Yellow Powder
Occurrence
Tyramine was originally a compound isolated from ergot alkaloids and decaying animal tissue. It has pharmacological effects such as increasing blood pressure and exciting the uterus.
Uses
Tyramine hydrochloride is a sympathomimetic, the hydrochloride salt of the naturally-occurring monoamine derived from the amino acid tyrosine. Tyramine acts as a catecholamine releasing agent but cannot cross the blood-brain barrier. Tyramine hydrochloride is an amino acid that helps regulate blood pressure. Tyramine hydrochloride occurs naturally in the body, and it's found in certain foods.
Application
Tyramine hydrochloride (T-HCl) is a kind of fluorogenic substrate of peroxidase. It is a naturally occurring monoamine derived from tyrosine. Tyramine Hydrochloride has been used:
coinfused with adenosine in control subjects and patients in order to reduce leg blood flow by 50% without affecting arterial blood pressure.
labelled with fluorescence dyes (Atto 488 and Atto 655) to serve as a substrate for peroxidase in immunofluorescence analysis.
used in dimethylformamide, labelled with 5-(and-6)carboxyfluorescein, succinimidyl ester/biotin to serve as a substrate for peroxidase in tyramide signal amplification.
Neurotransmitter.
Biochem/physiol Actions
Tyramine is a biogenic amine and a neuromodulator localized to the nervous system. Tyrosine decarboxylase catalysis the formation of tyramine from tyrosine. Tyramine is found to be associated with a number of psychiatric disorders. Tyramine ingestion depletes serotonin, epinephrine and norepinephrine reserves. This results in elevated biological events such as cardiovascular function, blood pressure, glucose production and overall metabolism. It also causes depression, migraine and insomnia. Tyramine is present is several food sources. The process of food fermentation and spoilage increases its tyramine content.
Synthesis
Tyramine [2-(p-hydroxyphenyl) ethylamine], a significant metabolite of tyrosine, enzymatic synthesis of tyramine was established by two-step biocatalytic reaction. Firstly, l-tyrosine was prepared from raw pyruvate fermentation broth under the catalysis of TPL. Pyruvate fermentation broth was simply centrifuged, and then the supernatant was diluted and used as substrate to produce l-tyrosine. Secondly, l-tyrosine was collected as starting material to synthesize tyramine by immobilized TDC cells from Lactobacillus brevis. Pyridoxal phosphate was the common coenzyme for these two enzymes.
Purification Methods
Crystallise the hydrochloride from EtOH by addition of diethyl ether, or from conc HCl. [Beilstein 3 II 355.]
