Identification of Food Spoilage Fungi Using MALDI-TOF MS: Spectral Database Development and Application to Species Complex.

Fungi, including filamentous fungi and yeasts, are major contributors to global food losses and waste due to their ability to colonize a very large diversity of food raw materials and processed foods throughout the food chain. In addition, numerous fungal species are mycotoxin producers and can also be responsible for opportunistic infections. In recent years, MALDI-TOF MS has emerged as a valuable, rapid and reliable asset for fungal identification in order to ensure food safety and quality.

Microbiota associated with commercial dry-aged beef in France.

Meat dry aging consists in storing unpackaged meat in a cold room, and at a specific and controlled relative humidity (RH), for a period of 1 to 5 weeks or more. This practice has become widespread in recent years due to its positive effect on the tenderness of the meat but also on other organoleptic characteristics and therefore its market value. The objective of this work was to study the bacterial and fungal microbiota of dry-aged beef at the commercial stage by both culture-dependent and -independent approaches.

Heterologous Expression and Biochemical Characterization of a New Chloroperoxidase Isolated from the Deep-Sea Hydrothermal Vent Black Yeast Hortaea werneckii UBOCC-A-208029.

The initiation of this study relies on a targeted genome-mining approach to highlight the presence of a putative vanadium-dependent haloperoxidase-encoding gene in the deep-sea hydrothermal vent fungus Hortaea werneckii UBOCC-A-208029. To date, only three fungal vanadium-dependent haloperoxidases have been described, one from the terrestrial species Curvularia inaequalis, one from the fungal plant pathogen Botrytis cinerea, and one from a marine derived isolate identified as Alternaria didymospora. In this study, we describe a new vanadium chloroperoxidase from the black yeast H.

Impact of water activity on the radial growth of fungi in a dairy environment.

Filamentous fungi are used in the dairy industry as adjunct cultures in fermented products, but can also lead to food spoilage, waste and economic losses. The control of filamentous fungi with abiotic factors contributes to longer food shelf life and prevention of fungal spoilage. One of the main abiotic factors for controlling fungal growth in foods is water activity (a).

Brine salt concentration reduction and inoculation with autochthonous consortia: Impact on Protected Designation of Origin Nyons black table olive fermentations.

Nyons table olives, named after the French city where they are processed, are naturally fermented black table olives. Their specificity relies on the use of the "Tanche" olive variety harvested at full maturity and their slow spontaneous fermentation in 10% salt brine driven by yeast populations. This study aimed at investigating the benefit of inoculating autochthonous consortia to produce Nyons table olives by fermentation in 10% salt brine and in reduced salt conditions (8%).

Microbial Ecology of French Dry Fermented Sausages and Mycotoxin Risk Evaluation During Storage.

Dry fermented sausages are produced worldwide by well-controlled fermentation processes involving complex microbiota including many bacterial and fungal species with key technological roles. However, to date, fungal diversity on sausage casings during storage has not been fully described. In this context, we studied the microbial communities from dry fermented sausages naturally colonized or voluntarily surface inoculated with molds during storage using both culture-dependent and metabarcoding methods.

Use of metabarcoding and source tracking to identify desirable or spoilage autochthonous microorganism sources during black olive fermentations.

This study aimed at investigating the influence of the process environment and raw materials as sources of microorganisms during Nyons black table olive fermentations. Fermented olives and/or brine from spoiled fermentation tanks were analyzed and compared to good quality samples from fermentations collected during 3 consecutive harvest years. Fresh olives, salt and different process environment samples were also analyzed.

Linking Pélardon artisanal goat cheese microbial communities to aroma compounds during cheese-making and ripening.

Pélardon is an artisanal French raw goat's milk cheese, produced using natural whey as a backslop. The aim of this study was to identify key microbial players involved in the acidification and aroma production of this Protected Designation of Origin cheese. Microbial diversity of samples, collected from the raw milk to 3-month cheese ripening, was determined by culture-dependent (MALDI-TOF analysis of 2877 isolates) and -independent (ITS2 and 16S metabarcoding) approaches and linked to changes in biochemical profiles (volatile compounds and acids).

Deciphering Microbial Community Dynamics and Biochemical Changes During Nyons Black Olive Natural Fermentations.

French PDO Nyons black table olives are produced according to a traditional slow spontaneous fermentation in brine. The manufacture and unique sensorial properties of these olives thus only rely on the autochthonous complex microbiota. This study aimed at unraveling the microbial communities and dynamics of Nyons olives during a 1.

Deciphering the Infectious Process of in Lupin through Transcriptomic and Proteomic Analysis.

The fungal phytopathogen is responsible for lupin anthracnose, resulting in significant yield losses worldwide. The molecular mechanisms underlying this infectious process are yet to be elucidated. This study proposes to evaluate gene expression and protein synthesis during lupin infection, using, respectively, an RNAseq-based transcriptomic approach and a mass spectrometry-based proteomic approach.

Water Microbiota in Greenhouses With Soilless Cultures of Tomato by Metabarcoding and Culture-Dependent Approaches.

Water supply, in hydroponic greenhouses, can originate from groundwater, surface water or rainwater stored in open tanks. To limit contamination of water supply, several methods have been used including active and passive methods such as slow filtration techniques which consist in passing the nutrient solutions slowly through filters. The purpose of this study was to describe the microbiota associated with water sampled before entering greenhouses and in recirculating nutrient solutions, either before or after running through a biofiltration system.

Phylogenetic Diversity and Effect of Temperature on Pathogenicity of .

Although lupin anthracnose caused by is a significant threat for spring and winter lupin crops, it has been poorly studied so far. This study aimed at characterizing the (i) phylogenetic, (ii) morphological, and (iii) physiological diversity of collected isolates from anthracnose-affected lupins. The genetic identification of representative isolates ( = 71) revealed that they were all species, further confirming that lupin anthracnose is caused by this species.

Microbiota Associated with Dromedary Camel Milk from Algerian Sahara.

Despite the fact that camel milk represents a valuable food source, the fungal diversity of raw camel milk has been poorly studied so far. Here, we investigated the fungal and bacterial communities found in dromedary camel milk from Ghardaia, a representative region of Algerian Sahara. The application of both culture-dependent and independent molecular techniques, based on dHPLC analysis and metabarcoding of ITS region, provided a complementary biodiversity assessment of camel milk fungi which was composed of 15 different taxa.

Selection of Algerian lactic acid bacteria for use as antifungal bioprotective cultures and application in dairy and bakery products.

In the context of a demand for "preservative-free" food products, biopreservation appears as a promising alternative to either replace or reduce the use of chemical preservatives. The purpose of this study was to evaluate the antifungal activity of a collection of lactic acid bacteria (n = 194), and then to evaluate the applicability and efficacy of selected ones used as bioprotective cultures against mold spoilers in dairy and bakery products. First, lactic acid bacteria were isolated from various Algerian raw milk samples and Amoredj, a traditional fermented product.

Development of antifungal ingredients for dairy products: From in vitro screening to pilot scale application.

Biopreservation represents a complementary approach to traditional hurdle technologies for reducing microbial contaminants (pathogens and spoilers) in food. In the dairy industry that is concerned by fungal spoilage, biopreservation can also be an alternative to preservatives currently used (e.g.

Development and application of MALDI-TOF MS for identification of food spoilage fungi.

Filamentous fungi are frequently involved in food spoilage and cause important food losses and substantial economic damage. Their rapid and accurate identification is a key step to better manage food safety and quality. In recent years, MALDI-TOF MS has emerged as a powerful tool to identify microorganisms and has successfully been applied to the identification of filamentous fungi especially in the clinical context.

Technical note: High-throughput method for antifungal activity screening in a cheese-mimicking model.

In this study, we developed a high-throughput antifungal activity screening method using a cheese-mimicking matrix distributed in 24-well plates. This method allowed rapid screening of a large variety of antifungal agent candidates: bacterial fermented ingredients, bacterial isolates, and preservatives. Using the proposed method, we characterized the antifungal activity of 44 lactic acid bacteria (LAB) fermented milk-based ingredients and 23 LAB isolates used as protective cultures against 4 fungal targets (Mucor racemosus, Penicillium commune, Galactomyces geotrichum, and Yarrowia lipolytica).

Assessment of the antifungal activity of Lactobacillus and Pediococcus spp. for use as bioprotective cultures in dairy products.

Fungi are commonly involved in dairy product spoilage and the use of bioprotective cultures can be a complementary approach to reduce food waste and economic losses. In this study, the antifungal activity of 89 Lactobacillus and 23 Pediococcus spp. isolates against three spoilage species, e.

Hepatotoxicity of fusariotoxins, alone and in combination, towards the HepaRG human hepatocyte cell line.

While the reality of mycotoxin co-occurrence in food commodities is now established, their effects in mixtures are not well studied. The present study investigated the individual and combined effects of deoxynivalenol (DON), nivalenol (NIV), T-2 toxin (T2), fumonisin B1 (FB1), zearalenone (ZEA) and moniliformin (MON) fusariotoxins on cell viability and cell death mechanisms in proliferating HepaRG cells, a human derived liver cell line. In addition, DON-ZEA being one of the most widespread mycotoxin mixtures in grains worldwide, its effect on the expression levels of genes encoding for sets of hepatocyte-specific functions was studied.

Individual and combined toxicological effects of deoxynivalenol and zearalenone on human hepatocytes in in vitro chronic exposure conditions.

While numerous surveys highlighted the natural co-occurrence of mycotoxins in food, data about their toxicological combined effects is still limited. This is especially the case for chronic exposure conditions, although the latter are more representative of the mycotoxin risk associated with food consumption than acute exposure. In the present study, cell viability and gene expression levels of relevant hepatocyte-specific functions were evaluated for the HepaRG human liver cell line exposed to deoxynivalenol (DON) and/or zearalenone (ZEA) during 14, 28 and 42days at three subtoxic concentrations corresponding to i) the determined average exposure dose of French adult population, ii) the tolerable daily intake established by the Joint FAO/WHO Expert Committee and iii) the maximum level permitted by the European regulation in cereals intended for direct human consumption.

Unraveling microbial ecology of industrial-scale Kombucha fermentations by metabarcoding and culture-based methods.

Kombucha, historically an Asian tea-based fermented drink, has recently become trendy in Western countries. Producers claim it bears health-enhancing properties that may come from the tea or metabolites produced by its microbiome. Despite its long history of production, microbial richness and dynamics have not been fully unraveled, especially at an industrial scale.

Diversity of spoilage fungi associated with various French dairy products.

Yeasts and molds are responsible for dairy product spoilage, resulting in significant food waste and economic losses. Yet, few studies have investigated the diversity of spoilage fungi encountered in dairy products. In the present study, 175 isolates corresponding to 105 from various spoiled dairy products and 70 originating from dairy production environments, were identified using sequencing of the ITS region, the partial β-tubulin, calmodulin and/or EFα genes, and the D1-D2 domain of the 26S rRNA gene for filamentous fungi and yeasts, respectively.

Spectrum of mutations in the renin-angiotensin system genes in autosomal recessive renal tubular dysgenesis.

Autosomal recessive renal tubular dysgenesis (RTD) is a severe disorder of renal tubular development characterized by early onset and persistent fetal anuria leading to oligohydramnios and the Potter sequence, associated with skull ossification defects. Early death occurs in most cases from anuria, pulmonary hypoplasia, and refractory arterial hypotension. The disease is linked to mutations in the genes encoding several components of the renin-angiotensin system (RAS): AGT (angiotensinogen), REN (renin), ACE (angiotensin-converting enzyme), and AGTR1 (angiotensin II receptor type 1).

Phenotype and outcome in hereditary tubulointerstitial nephritis secondary to UMOD mutations.

Background: UMOD mutations cause familial juvenile hyperuricemic nephropathy (FJHN) and medullary cystic kidney disease (MCKD), although these phenotypes are nonspecific.

Design, Setting, Participants, & Measurements: We reviewed cases of UMOD mutations diagnosed in the genetic laboratories of Necker Hospital (Paris, France) and of Université Catholique de Louvain (Brussels, Belgium). We also analyzed patients with MCKD/FJHN but no UMOD mutation.