IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Study of fungal and bacterial laccases for the reduction of ochratoxin A content in model wine

Study of fungal and bacterial laccases for the reduction of ochratoxin A content in model wine

Abstract

Ochratoxin A (OTA) is a mycotoxin produced by several filamentous fungi infecting grape bunches (Penicillium and Aspergillus spp.), this toxin pass to must when grapes are crushed and later it is found in wine. Following the evaluations of the toxicity of OTA, European Commission Regulations have been promulgated introducing upper limits for OTA concentrations in various commodities (cereals, cereal products, dried vine fruit, coffee, wine, grape juice, baby foods and dietary foods for special medical purposes). The use of fungal (Plerotus eryngii, Pleurotus pulmonarius and Trametes versicolor), and bacterial (Streptomyces coelicor) laccases permits to decrease Ochratoxin A, and other mycotoxins in buffer systems containing various natural and artificial redox mediators. Recently several laccases from lactic acid bacteria of wine and other foods have been isolated, identified and characterized. The aim of this research was to study the effect of synthetic and natural mediators on the degradation of Ochratoxin A (OTA) using laccases from Botrytis cinerea (fungal) and lactic acid bacteria. Studies were carried out in acetate buffer and model wine and evaluated the effect of different oenological factors (pH, SO2 and ethanol content). Quantification of OTA was accomplished by LC-QTOF analysis. Results showed that fungal and bacterial laccases alone were not effective in decreasing OTA content and the presence of redox mediators was required to achieve some reduction of OTA concertation, both in buffer and model wine.  Monomeric flavanols catechin and epicatechin were the most effective mediators among those assayed, followed by ferulic acid. Caftaric acid and the flavonols quercetin and quercetin-3-O-rutinoside were almost ineffective as mediators. SO2 at a concentration of 30 mg/L was able to completely prevent OTA degradation. These preliminary results confirmed the activity of laccase enzymes against ochratoxin A and provide knowledge on the effects of natural redox mediators suggesting new biological alternative strategies to eliminate undesirable substances present in wine.

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Gómez-Alonso Sergio1, Martínez Tania Paniagua1, Pérez-Navarro José2, Olmeda Isidoro3, Pardo Isabel3, Ferrer Sergi3, Canals Joan Miquel4 and Zamora Fernando4

1Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha
2Higher Technical School of Agronomic Engineering, University of Castilla-La Mancha
3Faculty of Biological Sciences, University of Valencia
4Faculty of Oenology, Rovira i Virgili University

Contact the author

Keywords

ochratoxin A, laccase, fungal, lactic acid bacteria, phenolic compounds

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Antioxidant activity of grape seed and skin extract during ripening

Reactive oxygen species (ROS) play an important physiological role in the body’s defense and being involved in numerous signaling pathways 1, 2. When the balance between oxidant and antioxidant species is altered in favor of ROS, oxidative stress is generated. In this condition the cells are damaged as the ROS oxidize important cellular components, such as proteins, lipids, nucleic acids and

Applications pratiques du zonage vitivinicole

Le zonage vitivinicole présente toute une série d’applications pratiques. Son importance est en train d’augmenter, soit en fonction des moyens techniques chaque fois plus performants, qui rendent possible le développement des zonages de plus en plus intégrées, consistants et utiles, soit en fonction d’un marché de plus en plus mondialisé. L’article situe la contribution du zonage au niveau de la production vitivinicole et du développement du territoire.

INSIGHTS ON THE ROLE OF GENES ON AROMA FORMATION OF WINES

Yeast secondary metabolism is a complex network of biochemical pathways and the genetic profile of the yeast carrying out the alcoholic fermentation is obviously important in the formation of the metabolites conferring specific odors to wine. The aim of the present research was to investigate the relative expression of genes involved in flavor compound production in eight different Saccharomyces cerevisiae strains.
Two commercial yeast strains Sc1 (S.cerevisiae x S.bayanus) and Sc2 (S.cerevisiae) and six indigenous S. cerevisiae strains (Sc3, Sc4, Sc5, Sc6, Sc7, Sc8) isolated during spontaneous fermentations were inoculated in Assyrtiko and Vidiano grape must.

Polyphenol targeted and untargeted metabolomics on rosé wines : impact of protein fining on polyphenolic composition and color

Color is one of the key elements in the marketing of rosé wines[1]. Their broad range of color is due to the presence of red pigments (i.e. anthocyanins and their derivatives) and yellow pigments, likely including polyphenol oxidation products. Clarifying agents are widely used in the winemaking industry to enhance wine stability and to modulate wine color by binding and precipitating polyphenols[2]. During this study, the impact of four different fining agents (i.e. two vegetal proteins, potatoe and pea proteins, an animal protein, casein, and a synthetic polymer, polyvinylpolypyrrolidone, PVPP) on Syrah Rose wine color and phenolic composition (especially pigments) was investigated. Color was characterized by spectrophotometry analysis using the CIELab system in addition to absorbance data. Fining using PVPP had the highest impact on redness (a*) and lightness (L*) parameters, whereas patatin strongly reduced the yellow component (b*) of the wine color. In parallel, the concentration of 125 phenolic compounds including 85 anthocyanins and derived pigments was determined by Ultra High Performance Liquid Chromatography coupled to elestrospray ionisaion triple-quadrupole Mass Spectrometry (UHPLC-QqQ-ESI-MS) in the Multiple Reaction Monitoring mode[3] .

METHYL SALICYLATE: A TRENDY COMPOUND MARKER OF ZELEN, A UNIQUE SLOVENIAN VARIETY

The wine market interest for autochthonous varieties, particularly from less known wine regions, has significantly raised in the past few years. In that context, Slovenia, a small country from central Europe with a long winemaking tradition, is getting more and more attention, particularly through its range of unique regional varieties. Among them, Zelen, meaning “green” in Slovene, can only be found in the Vipava valley region, located on the western side of the country, near the border with Italy. When they are young, Zelen wines display very singular aromas reminiscent of rosemary, sage and white fruit. Despite its uniqueness, Zelen wine aromatic typicality is poorly documented in the literature.