Biogenic amines are naturally occurring compounds with biological activity. They are present in many living organisms, including plants, animals, and microorganisms, and are also found in various foods.
Understanding Biogenic Amines
Biogenic amines are low molecular weight organic bases. They are primarily formed through the enzymatic removal of a carboxyl group from amino acids, a process called decarboxylation. These compounds are categorized into groups such as monoamines, diamines, and polyamines.
Examples include histamine, derived from histidine, and tyramine, from tyrosine. Serotonin and dopamine are synthesized from tryptophan and tyrosine. Putrescine, a diamine, is formed from ornithine.
Roles in the Human Body
Within the human body, biogenic amines perform a variety of functions, acting as neurotransmitters, hormones, and immune modulators. Serotonin, for instance, is a neurotransmitter primarily known for its involvement in mood regulation, sleep-wake cycles, and appetite. Dopamine is another neurotransmitter that influences motivation, reward, and the coordination of bodily movements.
Norepinephrine, also a neurotransmitter, is synthesized from dopamine and contributes to the body’s “fight or flight” response, affecting heart rate and blood flow. Histamine acts as a signaling molecule in the immune system, regulating inflammation and allergic reactions, and also functions as a neurotransmitter involved in arousal and attention. These compounds collectively regulate various physiological processes, including blood pressure, digestion, and cognitive abilities.
Biogenic Amines in Food
Biogenic amines are commonly found in food, primarily forming through microbial activity during processes like fermentation, aging, and spoilage of protein-rich foods. Microorganisms, particularly bacteria, produce enzymes called amino acid decarboxylases that convert free amino acids in food into their corresponding amines. The concentration of these amines can vary significantly depending on factors such as the raw materials’ hygiene, microbial composition, and the conditions and duration of fermentation.
Foods frequently high in biogenic amines include aged cheeses, fermented meats and fish products, wine, beer, and sauerkraut. For example, tyramine and histamine levels can be elevated in cheese during ripening. The presence of biogenic amines also indicates food quality and freshness, with higher levels often signaling spoilage, making them relevant for food safety assessments.
Health Implications
The impact of biogenic amines on human health becomes noticeable when they are consumed in high quantities or when an individual’s body has an impaired ability to metabolize them. Normally, enzymes like monoamine oxidase (MAO) and diamine oxidase (DAO) in the digestive tract rapidly break down these amines. However, if these enzymes are deficient or inhibited, even typical amounts of biogenic amines can lead to adverse reactions.
Conditions like histamine intolerance can arise from an inability to properly break down histamine, leading to symptoms such as flushing, headaches, skin rashes, nausea, vomiting, and changes in blood pressure. Tyramine can trigger migraines in sensitive individuals. This is particularly relevant for individuals taking monoamine oxidase inhibitors (MAOIs), as these medications prevent the breakdown of tyramine, leading to a dangerous increase in blood pressure, often referred to as the “cheese effect.” Other biogenic amines like putrescine and cadaverine, while not directly toxic, can enhance the negative effects of histamine by interfering with its metabolism.