Biogenic amine production by the wine Lactobacillus brevis IOEB 9809 in systems that partially mimic the gastrointestinal tract stress

Pasquale Russo,Giuseppe Spano,Pilar Fernández De Palencia,Andrea Romano,Paloma López,Patrick Lucas,María Fernández

doi:10.1186/1471-2180-12-247

Abstract

BackgroundIngestion of fermented foods containing high levels of biogenic amines (BA) can be deleterious to human health. Less obvious is the threat posed by BA producing organisms contained within the food which, in principle, could form BA after ingestion even if the food product itself does not initially contain high BA levels. In this work we have investigated the production of tyramine and putrescine by Lactobacillus brevis IOEB 9809, of wine origin, under simulated gastrointestinal tract (GIT) conditions.ResultsAn in vitro model that simulates the normal physiological conditions in the human digestive tract, as well as Caco-2 epithelial human cell lines, was used to challenge L. brevis IOEB 9809, which produced both tyramine and putrescine under all conditions tested. In the presence of BA precursors and under mild gastric stress, a correlation between enhancement of bacterial survival and a synchronous transcriptional activation of the tyramine and putrescine biosynthetic pathways was detected. High levels of both BA were observed after exposure of the bacterium to Caco-2 cells.ConclusionsL. brevis IOEB 9809 can produce tyramine and putrescine under simulated human digestive tract conditions. The results indicate that BA production may be a mechanism that increases bacterial survival under gastric stress.

Highlights

Ingestion of fermented foods containing high levels of biogenic amines (BA) can be deleterious to human health
Behaviour of L. brevis IOEB 9809 under simulated upper digestive tract conditions To test for BA production and the influence of active BA biosynthetic pathways on bacterial survival IOEB 9809 was grown to approximately 8 × 108 CFU mL-1 in Man Rogosa Sharpe (MRS) medium in the absence or presence of 10 mM tyrosine or 4.38 mM agmatine sulphate or both
Under mild gastric stress bacterial survival improved in the presence of BA precursors and a synchronous transcriptional activation of the tyramine and putrescine biosynthetic pathways was detected

Summary

Introduction

Ingestion of fermented foods containing high levels of biogenic amines (BA) can be deleterious to human health. In this work we have investigated the production of tyramine and putrescine by Lactobacillus brevis IOEB 9809, of wine origin, under simulated gastrointestinal tract (GIT) conditions. Biogenic amines (BA) are natural toxins that can occur in fermented foods and beverages and may cause adverse health effects [1,2,3]. One open question is whether BA-producers present in fermented foods and beverages are able to survive in the human GIT and still produce BA. Some LAB possess high resistance to gastrointestinal stress and frequently have adhesive properties that allow them to colonize the intestinal tract [15]. Possession of a functional tyramine biosynthetic pathway enhanced the binding of E. durans to Caco-2 human intestinal cells [16]

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Conclusion