terclim by ICS banner
IVES 9 IVES Conference Series 9 OTA DEGRADATION BY BACTERIAL LACCASEST

OTA DEGRADATION BY BACTERIAL LACCASEST

Abstract

Laccases from lactic acid bacteria (LAB) are described as multicopper oxidase enzymes with copper union sites. Among their applications, phenolic compounds’ oxidation and biogenic amines’ degrada-tion, have been described. Besides, the role of LAB in the toxicity reduction of ochratoxin A (OTA) has been reported (Fuchs et al., 2008; Luz et al., 2018). Fungal laccases, but not bacterial laccases, have been screened for OTA and mycotoxins’ degradation (Loi et al., 2018). OTA is a mycotoxin produced by some fungal species, such as Penicillium and Aspergillus sp., which infect grape bunches used for winemaking. OTA degradation is paramount given that it has been described as human-health harmful according to EFSA.

The work aimed to evaluate the OTA degrading capacity of three heterologous LAB laccases expressed in E. coli. The experimental procedure consisted on testing bacterial laccases from L. lactis, L. paracasei and P. parvulus in acetate buffer pH 4 with or without CuSO4 and OTA in presence and absence of several concentrations of epicatequin and complete polyphenolic extracts from red and white wine as media-tors. Degradation of OTA was followed and quantified by analyzing samples with HPLC-QToF-MS.

According to the results, OTA degradation in the reaction buffer with copper was at least three times higher than without copper. In addition, 0.75 mM epicatequin was the optimum concentration to obtain the highest OTA degradation with L. paracasei laccase (78%). Then, P. parvulus and L. lactis laccases were tested at this concentration, averaging 70% degradation. Finally, mean values of 40% and 10% OTA de-gradation were revealed when using polyphenolic extracts from red and white wine, respectively, for the three laccases. The application of these LAB laccases on OTA degradation in real wine needs to be further explored.

 

1. Fuchs S., et al. (2008). Food Chem Toxicol; 46:1398-1407.
2. Loi M., et al. (2018). Food Control; 90: 401-406.
3. Luz C., et al. (2018). Food Chem Toxicol; 112: 60-66.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Isaac Monroy¹, Isabel Pardo¹, Sergi Ferrer¹, José Pérez-Navarro², Sergio Gómez-Alonso²

1. ENOLAB, Institute BIOTECMED and Microbiology and Ecology Dept, University of Valencia
2. IRICA, University of Castilla-La Mancha

Contact the author*

Keywords

Ochratoxin A reduction, lactic acid bacteria laccases, polyphenolic compounds, redox media-tors

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

EFFECTS OF HYDROXYTYROSOL ON THE CHEMICAL PROFILE AND SENSORY ATTRIBUTES OF A RED TUSCAN WINE

The chemical profile and sensory attributes were studied in Borrigiano IGT Toscana wine (Italy), a blend of Sangiovese 85% and Cabernet Sauvignon 15% grapes harvested in September 2020, where 2-(3,4-dihydroxyphenyl)ethanol (hydroxytyrosol, HT, [1]) was added to a 750-ml wine bottle in 3 different amounts (30, 60, 120 mg) and compared with the control (no HT addition). The study aimed to evaluate whether Polyphenol-HT1®, a high purity HT (>99%) produced by Nova Mentis using biotechnology, could be used as a supplement to sulfites and how it would impact the sensory and chemical profile of this wine [2]. Each sample was prepared in triplicate.

PESTICIDE RESIDUES IN THE VINEYARD ENVIRONMENTS: VINE LEAVES, GRAPE BERRIES, WINES, HONEYBEES AND ASIAN HORNETS

Synthetic pesticides are widely used in viticulture to ensure steady harvest quality and quantity. Fungicides are primarily used to control grapevine diseases but insecticides and herbicides are likewise used. Pesticide residues in viticultural areas currently represent a strong societal concern, but may also affect different trophic chains in such areas. In this project we wish to analyse honeybees collected from hives placed in different vineyards, their natural predator (the invasive hornet Vespa velutina), as well as the honey, grape berries, and wines produced.

Rootstock mediated responses of grapevine (Vitis vinifera L.) metabolism and physiology to combined water deficit and salinity stress in Syrah grafts

Water deficit and salinity are increasingly affecting the viticulture and wine industry. These two stresses are intimately related; understanding the physiological and metabolic responses of grapevines to water deficit, salinity and combined stress is critical for developing strategies to mitigate the nega- tive impacts of these stresses on wine grape production. These strategies can include selecting more tolerant grapevine cultivars and graft combinations, improving irrigation management, and using soil amendments to reduce the effects of salinity. For this purpose, understanding the response of grape- vine metabolism to altered water balance and salinity is of pivotal importance.

WINE SWIRLING: A FIRST STEP TOWARDS THE UNLOCKING OF THE WINE’STASTER GESTURE

Right after the pouring of wine in a glass, a myriad of volatile organic compounds, including ethanol, overwhelm the glass headspace, thus causing the so-called wine’s bouquet [1]. Otherwise, it is worth noting that during wine tasting, most people automatically swirl their glass to enhance the release of aromas in the glass headspace [1]. About a decade ago, Swiss researchers revealed the complex fluid mechanics underlying wine swirling [2]. However, despite mechanically repeated throughout wine tasting, the consequences of glass swirling on the chemical space found in the headspace of wine glasses are still barely known.

WHAT’S FUTURE FOR SANTORINI’S VITICULTURE IN THE CONTEXT OF CLIMATE CHANGE

The own-rooted vineyard of Santorini is a unique case of vineyard worldwide that is been cultivated for thousands of years. On the island’s volcanic soil, the vines are still cultivated with traditional techniques, which are adapted to the specific and extreme weather conditions that prevail on it. While climate change is a reality in the Mediterranean region, will Santorini vineyard endure its impact? The study of the traditional training systems, techniques and vine density, as well as the application of sustainable solutions (cover crops and use of kaolin etc.) revealed sustainable methods for the adaptation of the local viticulture to new climatic phenomena that tend to be more and more frequent in the region due to climate change.