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Journal of Fungi (Basel, Switzerland) May 2022Wine is a particularly complex beverage resulting from the combination of several factors, with yeasts being highlighted due to their fundamental role in its...
Wine is a particularly complex beverage resulting from the combination of several factors, with yeasts being highlighted due to their fundamental role in its development. For many years, non- yeasts were believed to be sources of spoilage and contamination, but this idea was challenged, and many of these yeasts are starting to be explored for their beneficial input to wine character. Among this group, is gaining relevance within the wine industry, owing to its low volatile acidity production, increased release of aromatic compounds and enhanced color intensity. In addition, this yeast was also attracting interest in other biotechnological areas, such as bread and beer fermentation. In this work, a set of 40 strains, of varied geographical and technological origins, was gathered in order to characterize the phenotypic behavior of this species, focusing on different parameters of biotechnological interest. The fermentative performance of the strains was also evaluated through individual fermentations in synthetic grape must with the isolates' metabolic profile being assessed by HPLC. Data analysis revealed that growth is significantly affected by high temperature (37 °C) and ethanol concentrations (up to 18%), alongside 1.5 mM SO, showing variable fermentative power and yields. Our computation models suggest that the technological origin of the strains seems to prevail over the geographical origin as regards the influence on yeast properties. The inter-strain variability and profile of the products through the fermentative processes reinforce the potential of from a biotechnological point of view.
PubMed: 35736052
DOI: 10.3390/jof8060569 -
AIMS Microbiology 2021Yeasts constitute an important part of cheeses, and especially the artisanal ones. The current study reviews the occurrence of yeasts in different cheese varieties and... (Review)
Review
Yeasts constitute an important part of cheeses, and especially the artisanal ones. The current study reviews the occurrence of yeasts in different cheese varieties and the role of yeasts in cheesemaking process. The use of molecular methods for identification and strain typing has extended the knowledge for yeast diversity in cheeses. For the study of the occurrence of yeasts in different cheese types, seven categories are used, that is: 1) hard, 2) semi-hard, 3) soft, which includes soft pasta-filata and whey cheeses, 4) white brined cheeses, 5) mould surface ripened, 6) bacterial surface ripened cheeses, and 7) blue cheeses. For some cheese types, yeasts are the main microbial group, at least for some part of their ripening process, while for some other types, yeasts are absent. Differences between industrially manufactured cheeses and artisanal cheeses have specified. Artisanal cheeses possess a diverse assortment of yeast species, mainly belonging to the genera , , , , , , , , , , , , , , , and . The role of the yeasts for selected cheeses from the seven cheese categories is discussed.
PubMed: 35071942
DOI: 10.3934/microbiol.2021027 -
Journal of Fungi (Basel, Switzerland) Aug 2021has attracted interest in recent years, especially due to its biotechnological potential, arising from its flavor- and aroma-enhancing properties when used in wine,... (Review)
Review
has attracted interest in recent years, especially due to its biotechnological potential, arising from its flavor- and aroma-enhancing properties when used in wine, beer or bread dough fermentation, as well as from its remarkable resistance to osmotic and freezing stresses. In the present review, genomic, biochemical, and phenotypic features of are described, comparing them with other species, particularly with the biotechnologically well-established yeast, . We conclude about the aspects that make this yeast a promising biotechnological model to be exploited in a wide range of industries, particularly in wine and bakery. A phylogenetic analysis was also performed, using the core proteome of , to compare the number of homologous proteins relative to the most closely related species, understanding the phylogenetic placement of this species with robust support. Lastly, the genetic tools available for improvement are discussed, focusing on adaptive laboratorial evolution and its potential.
PubMed: 34575750
DOI: 10.3390/jof7090712 -
Food Microbiology Jun 2023The use of Torulaspora delbrueckii in the alcoholic fermentation (AF) of grape must is increasingly studied and used in the wine industry. In addition to the...
The use of Torulaspora delbrueckii in the alcoholic fermentation (AF) of grape must is increasingly studied and used in the wine industry. In addition to the organoleptic improvement of wines, the synergy of this yeast species with the lactic acid bacterium Oenococcus oeni is an interesting field of study. In this work, 60 strain combinations were compared: 3 strains of Saccharomyces cerevisiae (Sc) and 4 strains of Torulaspora delbrueckii (Td) in sequential AF, and four strains of O. oeni (Oo) in malolactic fermentation (MLF). The objective was to describe the positive or negative relationships of these strains with the aim of finding the combination that ensures better MLF performance. In addition, a new synthetic grape must has been developed that allows the success of AF and subsequent MLF. Under these conditions, the Sc-K1 strain would be unsuitable for carrying out MLF unless there is prior inoculation with Td-Prelude, Td-Viniferm or Td-Zymaflore always with the Oo-VP41 combination. However, from all the trials performed, it appears that the combinations of sequential AF with Td-Prelude and Sc-QA23 or Sc-CLOS, followed by MLF with Oo-VP41, reflected a positive effect of T. delbrueckii compared to inoculation of Sc alone, such as a reduction in L-malic consumption time. In conclusion, the obtained results highlight the relevance of strain selection and yeast-LAB strain compatibility in wine fermentations. The study also reveals the positive effect on MLF of some T. delbrueckii strains.
Topics: Saccharomyces cerevisiae; Torulaspora; Fermentation; Wine; Vitis; Oenococcus; Malates
PubMed: 36906299
DOI: 10.1016/j.fm.2022.104212 -
Journal of Agricultural and Food... Jul 2019Tryptophan, phenylalanine, and tyrosine play an important role as nitrogen sources in yeast metabolism. They regulate biomass production and fermentation rate, and their...
Tryptophan, phenylalanine, and tyrosine play an important role as nitrogen sources in yeast metabolism. They regulate biomass production and fermentation rate, and their catabolites contribute to wine health benefits and sensorial character through the yeast biotransformation of grape juice constitutes into biologically active and flavor-impacting components. A UHPLC-MS/MS method was applied to monitor 37 tryptophan/phenylalanine/tyrosine yeast metabolites both in extra- and intracellular extracts produced by the fermentation of two strains and one The results shed light on the intra- and extra-cellular metabolomic dynamics, by combining metabolic needs, stimuli, and signals. Among others, the results indicated (a) the production of 2-aminoacetophenone by yeasts, mainly by the two ; (b) the deactivation and/or detoxification of tryptophol via sulfonation reaction; and (c) the deacetylation of N-acetyl tryptophan ethyl ester and N-acetyl tyrosine ethyl ester by producing the corresponding ethyl esters.
Topics: Amino Acids, Aromatic; Chromatography, High Pressure Liquid; Nitrogen; Saccharomyces cerevisiae; Tandem Mass Spectrometry; Torulaspora
PubMed: 31264861
DOI: 10.1021/acs.jafc.9b01844 -
Microorganisms Apr 2024Multiple sclerosis (MS) arises from a complex interplay between host genetic factors and environmental components, with the gut microbiota emerging as a key area of...
Multiple sclerosis (MS) arises from a complex interplay between host genetic factors and environmental components, with the gut microbiota emerging as a key area of investigation. In the current study, we used ion torrent sequencing to delve into the bacteriome (bacterial microbiota) and mycobiome (fungal microbiota) of people with MS (pwMS), and compared them to healthy controls (HC). Through principal coordinate, diversity, and abundance analyses, as well as clustering and cross-kingdom microbial correlation assessments, we uncovered significant differences in the microbial profiles between pwMS and HC. Elevated levels of the fungus and the bacterial family were observed in pwMS, whereas beneficial bacterial taxa, such as and , were reduced. Notably, clustering analysis revealed overlapping patterns in the bacteriome and mycobiome data for 74% of the participants, with weakened cross-kingdom interactions evident in the altered microbiota of pwMS. Our findings highlight the dysbiosis of both bacterial and fungal microbiota in MS, characterized by shifts in biodiversity and composition. Furthermore, the distinct disease-associated pattern of fungi-bacteria interactions suggests that fungi, in addition to bacteria, contribute to the pathogenesis of MS. Overall, our study sheds light on the intricate microbial dynamics underlying MS, paving the way for further investigation into the potential therapeutic targeting of the gut microbiota in MS management.
PubMed: 38792701
DOI: 10.3390/microorganisms12050872 -
International Journal of Food... Nov 2022The current use of non-Saccharomyces yeasts in mixed fermentations increases the relevance of the interactions between yeast species. In this work, the interactions...
The current use of non-Saccharomyces yeasts in mixed fermentations increases the relevance of the interactions between yeast species. In this work, the interactions between Saccharomyces cerevisiae and Torulaspora delbrueckii were analyzed. For this purpose, fermentations with and without contact between strains of those yeast species were performed in synthetic must. Fermentation kinetics, yeast growth and dynamics were measured over time. Additionally, the effects of nitrogen and other nutrient supplementations on the mixed fermentations were determined. Our results showed that S. cerevisiae did not always dominate the sequential fermentations, and experiments without yeast contact (in which T. delbrueckii cells were removed from the medium before inoculating S. cerevisiae at 48 h) resulted in stuck fermentations except when the inoculum size was increased (from 2 × 10 to 10 cells/mL) or there was a supplementation of thiamine, zinc and amino acids at the same concentration as initially found in the synthetic must. Our findings highlight the importance of inoculum size and ensuring the availability of enough micronutrients for all yeast species, especially in sequential fermentations.
Topics: Amino Acids; Fermentation; Micronutrients; Nitrogen; Saccharomyces cerevisiae; Thiamine; Torulaspora; Wine; Zinc
PubMed: 36084391
DOI: 10.1016/j.ijfoodmicro.2022.109915 -
Journal of Bioscience and Bioengineering Jul 2020Saccharomyces cerevisiae can obtain xylose utilization capacity via integration of heterogeneous xylose reductase (XR) and xylitol dehydrogenase (XDH) genes into its...
Saccharomyces cerevisiae can obtain xylose utilization capacity via integration of heterogeneous xylose reductase (XR) and xylitol dehydrogenase (XDH) genes into its metabolic pathway, and XYL2 which encodes the XDH plays an essential role in this process. Herein, we reported that two hypothetical XYL2 genes from the multistress-tolerant yeasts of Issatchenkia orientalis and Torulaspora delbrueckii were cloned, and they encoded two XDHs, IoXyl2p and TdXyl2p, respectively, with the activities for oxidation of xylitol to xylulose. Comparative studies demonstrated that IoXyl2p and TdXyl2p, like the SsXyl2p from Scheffersomyces stipitis, were probably localized to the cytoplasm and strictly dependent on NAD rather than NADP as the cofactor for catalyzing the oxidation reaction of xylitol. IoXyl2p had the highest specific activity, maximum velocity (V), affinity to xylitol (K), and catalytic efficiency (k/K) among the three XDHs. The optimum temperature for oxidation of xylitol were at 45 °C by IoXyl2p and at 35 °C by TdXyl2p and SsXyl2p, and the optimum pH of IoXyl2p, TdXyl2p and SsXyl2p for oxidation of xylitol was 8.0, 8.5 and 7.5, respectively. Mg promoted the activities of IoXyl2p and TdXyl2p, but slightly inhibited the activity of SsXyl2p. Most metal ions had much weaker inhibition effects on IoXyl2p and TdXyl2p than SsXyl2p. IoXyl2p displayed the strongest salt resistance among the three XDHs. To summarize, IoXyl2p from I. orientalis and TdXyl2p from T. delbrueckii characterized in this study are considered to be the attractive candidates for the construction of genetically engineered S. cerevisiae for efficiently fermentation of carbohydrate in lignocellulosic hydrolysate.
Topics: Cloning, Molecular; D-Xylulose Reductase; Enzyme Stability; Fermentation; Fungal Proteins; Kinetics; Pichia; Torulaspora; Xylitol; Xylose
PubMed: 32171656
DOI: 10.1016/j.jbiosc.2020.02.012 -
Foods (Basel, Switzerland) Jan 2023Non-Saccharomyces (NS) yeasts are gaining popularity in modern winemaking for improving wine quality. Climate change is one of the biggest challenges winegrowing now...
Non-Saccharomyces (NS) yeasts are gaining popularity in modern winemaking for improving wine quality. Climate change is one of the biggest challenges winegrowing now faces in warm regions. Here, Lachancea thermotolerans LtS1 and Torulaspora delbrueckii TdS6 combined with Saccharomyces cerevisiae ScS13 isolated from Assyrtiko grapes from Santorini island were evaluated in grape must fermentation with the aim to mitigate major consequences of temperature rise. Different inoculation protocols were evaluated, including simultaneous and sequential mixed-strain inoculations, displaying significant variation in the chemical and kinetic characteristics. Both LtS1 and TdS6 could raise the titratable acidity (TA). TdS6 also reduced the volatile acidity (VA) and was thus chosen for further evaluation in microvinifications and pilot-scale fermentations. Consistent with lab-scale trials, sequential inoculation exhibited the longest persistence of TdS6 resulting in minimum VA levels. Diethyl succinate, ethyl propanoate, and ethyl isobutyrate were significantly increased in sequential inoculations, although a decline in the net total ester content was observed. On the other hand, significantly higher levels of TA, succinic acid, and 2-methylpropanoic were associated with sequential inoculation. The overall performance of TdS6 coupled with a high compatibility with S. cerevisiae suggests its use in the fermentation of Santorini-Assyrtiko or other high sugar musts for the production of structured dry or sweet wines.
PubMed: 36613407
DOI: 10.3390/foods12010191 -
Molecules (Basel, Switzerland) Apr 2024The effects of different fermentation methods utilizing 1004 and 32169 on the physicochemical properties, organic acid content, polyphenol and flavonoid...
The effects of different fermentation methods utilizing 1004 and 32169 on the physicochemical properties, organic acid content, polyphenol and flavonoid concentrations, antioxidant activity, and volatile aroma compounds of Huaniu apple cider were investigated in this study. Employing methods of single inoculation, co-inoculation, and sequential inoculation, it was found that sequential fermentation exhibited strong fermentative power in the initial stages, effectively reducing the content of soluble solids and achieving a balanced composition of malic, succinic, and citric acids while maintaining a lower titratable acidity. Sequential inoculation was observed to significantly enhance the total polyphenols and flavonoids, as well as the antioxidant capacity ( < 0.05). Specifically, in the synthesis of volatile aroma compounds, sequential inoculation significantly enhanced the richness and diversity of the Huaniu apple cider's aromas, particularly in terms of the concentration of ester compounds ( < 0.05). Principal component analysis further confirmed the superiority of sequential inoculation in terms of aroma component diversity and richness. The findings of this study suggest that sequential inoculation of fermentation with non- and is an effective strategy for optimizing the flavor characteristics of Huaniu apple cider, offering valuable theoretical support and practical guidance for enhancing cider quality and fostering the development of new products.
Topics: Saccharomyces cerevisiae; Malus; Fermentation; Torulaspora; Volatile Organic Compounds; Flavoring Agents; Polyphenols; Antioxidants; Flavonoids; Odorants
PubMed: 38675570
DOI: 10.3390/molecules29081750