Ochratoxin A Removal by Lactobacillus Plantarum V22 in Synthetic Substrates
Moncalvo A.1, Dordoni R.1, Silva A.1, Fumi M.D.1, Di Piazza S.2, Spigno G.1, *
Identifiers and Pagination:Year: 2018
First Page: 282
Last Page: 287
Publisher Id: TOBIOTJ-12-282
Article History:Received Date: 30/9/2018
Revision Received Date: 25/10/2018
Acceptance Date: 11/11/2018
Electronic publication date: 28/12/2018
Collection year: 2018
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: (https://creativecommons.org/licenses/by/4.0/legalcode). This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Ochratoxin A is a nephrotoxin which may occur in wines characterised by higher pH than the average. In the last decades the mechanisms responsible for ochratoxin A reduction by lactic acid bacteria have been investigated and identified as mainly cell walls adsorption and / or enzymatic conversion to ochratoxin-α, a non-toxic metabolite. Since lactic acid bacteria are involved in the malolactic fermentation during the wine-making process, selected starter cultures could be exploited to guarantee safe ochratoxin A level in wines also from contaminated grapes. A lactic acid bacteria strain (Lactobacillus plantarum V22) was previously selected for its ability of both degrading ochratoxin A and carrying out malolactic fermentation at high pH.
This study was aimed at assessing if the selected L. plantarum strain, can reduce ochratoxin A because it can use it as a carbon source.
L. plantarum V22 was grown in the presence of ochratoxin A in two different synthetic substrates, with or without malic acid, monitoring the reduction of ochratoxin A and the presence of ochratoxin α as an indicator for a toxin enzymatic hydrolysis. The presence of residual not hydrolysed ochratoxin A bound to the bacteria cell walls was also evaluated to quantify the ochratoxin A removal due to simple adsorption.
A significant reduction of 19.5 ± 2.0% in ochratoxin A concentration was observed only in the presence of malic acid. The quantified fraction of ochratoxin A adsorbed on cell walls was irrelevant and the metabolite ochratoxin α could not be detected.
There is a possibility that L. plantarum V22 can degrade ochratoxin A through a not yet identified metabolic pathway.