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Biogenic amines are frequently found in wine and other fermented food. We investigated the ability of 133 strains of lactic acid bacteria isolated from musts and wines of different origins to produce histamine, tyramine, and putrescine. We detected the genes responsible for encoding the corresponding amino acid decarboxylases through PCR assays using two primer sets for every gene: histidine decarboxylase (hdc), tyrosine decarboxylase (tdc), and ornithine decarboxylase (odc); these primers were taken from the literature or designed by us. Only one strain of Lactobacillus hilgardii was shown to possess the hdc gene, whereas four strains of Lactobacillus brevis had the tdc gene. None of the Oenococcus oeni strains, the main agents of malolactic fermentation, was a biogenic amine producer. All PCR amplicon band-positive results were confirmed by thin-layer chromatography and high-performance liquid chromatography analyses.

The aim of this work was to investigate if contaminating microorganisms, eventually present in bacteria and yeast preparations used as commercial starters in winemaking, have the ability to produce the biogenic amines histamine, putrescine and tyramine. Thirty commercial starters (14 yeasts Saccharomyces cerevisiae and 16 bacteria Oenococcus oeni) were cultured in synthetic broth and analyzed by TLC to detect amine production. Oenococcus oeni commercial preparations did not contain contaminants, but some yeast preparations resulted contaminated with amine-producing bacteria. Bacterial contaminants were isolated and analyzed for their ability to produce biogenic amines using HPLC and TLC. Decarboxylase genes were identified using PCR analysis followed by sequencing. Fermentations were performed in grape juice with two yeast commercial preparations containing bacterial contaminants to check if the potential biogenic amine production could happen also during winemaking. It was found that this production is possible; in particular, in the conditions used in this work, tyramine production was detected. Therefore, the results of this study have significance in relation to the risk of biogenic amines in wine. Moreover a novel species of Lactobacillus was found to be able to produce histamine.

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