Biogenic amines (BAs) are non-volatile low-molecular-weight nitrogenous organic bases which can be found in nearly all types of foods in a wide and variable range of concentrations. The most significant BAs occurring in foods are: histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine, and agmatine. BAs are produced by microorganisms, mainly bacteria, through the action of decarboxylases (EC 4.1.1.1. carboxy-lyases), which act selectively on precursor amino acids in which they remove the carboxyl group with the formation of the correspondent amine and CO2.
The decarboxylative pathways are activated for two main physiological reasons. Decarboxylation is one of the responses of cells to acid stress and it has been demonstrated that the transcription of many decarboxylase genes is induced by low pH and improves cell performances in acid conditions. Moreover, these pathways can bring supplementary energy for the cells by energizing the proton motive force associated to the membrane.
BAs can be produced both by Gram-positive and Gram-negative bacteria which occur naturally in food products, introduced by contamination, or added as a starter culture. Among Gram-negative bacteria, spoilage microorganisms belonging to Enterobacteriaceae and Pseudomonas are known as the major producers of cadaverine, histamine and putrescine. The ability to produce biogenic amines is widespread also among Gram-positive bacteria. The decarboxylase activity has been found in strains belonging to the genera Bacillus and Staphylococcus. However, the attention has been mainly focused on lactic acid bacteria (LAB), which are commonly present in fermented food.
Ingestion of food containing BAs represent a considerable toxicological risk for consumer health since these compounds can cause headache, heart palpitations, vomiting, diarrhea and hypertensive crisis. However, their toxic effect depends on the type of BAs, individual sensitivity or health status, and on the consumption of ethanol or monoamine oxidase inhibitory drugs, which interact with amino oxidase enzymatic systems responsible for the detoxification process of exogenous BAs.
Microorganisms (used as starter cultures, as well as those naturally occurring during ripening or in spontaneous fermentations) able to produce biogenic amines in model or in real systems may be evaluated. Furthermore, such subjects could include descriptions of novel knowledge and strategies for aminogenesis control: use of bioprotective cultures producing bacteriocins or other antimicrobial substances, technological additives, effects of packaging, other non-thermal treatments, use of microbial cultures able to degrade BAs and detoxifying them through the action of amino oxidases.
This Research Topic will focus on the aminobiogenic potential of fermented food microbiota, taking into consideration the conditions affecting biogenic amines accumulation (such as temperature, salt concentration, and pH) and the enzymes and genes involved in the biosynthetic mechanisms.
Subjects include:
• Genetic and metabolic organization of decarboxylases.
• The identification, determination, and monitoring of food microorganisms associated with harmful microbial metabolites.
• Methods for determining decarboxylase activity.
Please submit original research or review articles to be published in this Research Topic.
Biogenic amines (BAs) are non-volatile low-molecular-weight nitrogenous organic bases which can be found in nearly all types of foods in a wide and variable range of concentrations. The most significant BAs occurring in foods are: histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine, and agmatine. BAs are produced by microorganisms, mainly bacteria, through the action of decarboxylases (EC 4.1.1.1. carboxy-lyases), which act selectively on precursor amino acids in which they remove the carboxyl group with the formation of the correspondent amine and CO2.
The decarboxylative pathways are activated for two main physiological reasons. Decarboxylation is one of the responses of cells to acid stress and it has been demonstrated that the transcription of many decarboxylase genes is induced by low pH and improves cell performances in acid conditions. Moreover, these pathways can bring supplementary energy for the cells by energizing the proton motive force associated to the membrane.
BAs can be produced both by Gram-positive and Gram-negative bacteria which occur naturally in food products, introduced by contamination, or added as a starter culture. Among Gram-negative bacteria, spoilage microorganisms belonging to Enterobacteriaceae and Pseudomonas are known as the major producers of cadaverine, histamine and putrescine. The ability to produce biogenic amines is widespread also among Gram-positive bacteria. The decarboxylase activity has been found in strains belonging to the genera Bacillus and Staphylococcus. However, the attention has been mainly focused on lactic acid bacteria (LAB), which are commonly present in fermented food.
Ingestion of food containing BAs represent a considerable toxicological risk for consumer health since these compounds can cause headache, heart palpitations, vomiting, diarrhea and hypertensive crisis. However, their toxic effect depends on the type of BAs, individual sensitivity or health status, and on the consumption of ethanol or monoamine oxidase inhibitory drugs, which interact with amino oxidase enzymatic systems responsible for the detoxification process of exogenous BAs.
Microorganisms (used as starter cultures, as well as those naturally occurring during ripening or in spontaneous fermentations) able to produce biogenic amines in model or in real systems may be evaluated. Furthermore, such subjects could include descriptions of novel knowledge and strategies for aminogenesis control: use of bioprotective cultures producing bacteriocins or other antimicrobial substances, technological additives, effects of packaging, other non-thermal treatments, use of microbial cultures able to degrade BAs and detoxifying them through the action of amino oxidases.
This Research Topic will focus on the aminobiogenic potential of fermented food microbiota, taking into consideration the conditions affecting biogenic amines accumulation (such as temperature, salt concentration, and pH) and the enzymes and genes involved in the biosynthetic mechanisms.
Subjects include:
• Genetic and metabolic organization of decarboxylases.
• The identification, determination, and monitoring of food microorganisms associated with harmful microbial metabolites.
• Methods for determining decarboxylase activity.
Please submit original research or review articles to be published in this Research Topic.
