6533b831fe1ef96bd12995f3

RESEARCH PRODUCT

Amino acids role in biogenic amine production by Oenococcus Oeni

subject

description

In wine biogenic amines (BA) are mainly of microbial origin, Oenococcus oeni, the mainresponsible for malolactic fermentation, has been identified as a BA producer from nitrogenprecursors. Oenococcus oeni possess numerous amino acid auxotrophies that are precursors ofbiogenic amines. No study has been done so far to look at the relationship betweenauxotrophy for amino acids precursors of BA and the level of BA in the medium. In order todo so, 80 Oenococcus oeni strains were isolated from red wines. The detection of genesencoding the different decarboxylases responsible for BA synthesis has been realised. Inparallel, the auxotrophy for the four amino acids (Arg, Tyr, His, Phe) precursors of BA hascharacterized. Our results demonstrate that there is not direct correlation between auxotrophyand the accumulation of the corresponding BA as well as between the presence ofdecarboxylase gene and the accumulation of the corresponding BA. High levels of agmatineproduced from arginine decarboxylation by Oenococcus oeni is reported for the first time.Agmatine production is strain dependant. the most adapted to acidic environment is the strainwhith use arginine in higher level with same proportion for ADI pathway and argininedecarboxylase. Agmatine addition in wines reduce woody aroma probably by formation ofsciff bases between aromla compounds and amine