|Production of tyramine and putrescine by L. brevis IOEB 9809 in the presence of diverse BA precursors|
|BA precursor||Agmatine||Tyrosine||Agmatine +Tyrosine|
|BA produced||Put (μM)||Tym (μM)||Put (μM)||Tym (μM)|
|Saliva||22.33 ± 2.52a||26.08 ± 0.13a||32.66 ± 2.76ab||56.46 ± 3.06ad|
|G pH 5.0||37.67 ± 3.06b||78.29 ± 1.07b||57.27 ± 11.69c||194.63 ± 9.69e|
|G pH 4.1||36.00 ± 3.00b||122.30 ± 2.55c||39.22 ± 5.01b||174.46 ± 8.07f|
|G pH 3.0||11.59 ± 0.56d||82.18 ± 1.10bc||15.33 ± 1.05da||113.87 ± 5.27c|
|G pH 2.1||10.54 ± 0.46d||74.21 ± 1.07bd||14.32 ± 1.08da||76.10 ± 3.53b|
|G pH 1.8||11.21 ± 0.45d||62.26 ± 1.09d||13.42 ± 1.01da||50.91 ± 2.36ad|
Tyramine (Tym) and putrescine (Put) production were detected by RP-HPLC during the saliva and gastric stress simulation in presence of 10 mM tyrosine, 4.38 mM agmatine or both. Results are expressed in μM of BA produced by 108 CFU mL-1 in 20 min, they are the mean of three independent experiments and there are corrected for the CFU added to the experiment. Putrescine and tyramine were below the detection limits (2 nM and 2.5 nM) in the uninoculated MRS and in absence of the corresponding BA precursor. Differences were assessed by Anova test. Different superscript letters associated with values of the same BA indicate statistically significant differences (P < 0.05).
Russo et al.
Russo et al. BMC Microbiology 2012 12:247 doi:10.1186/1471-2180-12-247