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The total phenolic content and antioxidant activity of wine and fermented pomace (FP) from Cabernet Sauvignon grapes harvested at the stage of full ripeness were evaluated by spectrophotometric analysis. Wine and pomace were obtained after prolonged maceration during spontaneous and inoculated fermentation of fully ripe grapes. Three individual vinifications were inoculated with the following commercial yeasts: BDX (Lallemand, Montréal, QC, Canada), FX10 (Laffort, Bordeaux, France) and Qa23 (Lallemand, Montréal, QC, Canada). For each vinification, maceration lasted 0, 3, 5, 7, 14 and 21 days, respectively. The total phenolic content was determined spectrophotometrically using the Folin-Ciocalteu method. Two different methods were used to evaluate the antioxidant activity of the wine and pomace samples: the Ferric Reducing Activity of Plasma (FRAP) and the Trolox Equivalent Antioxidant Capacity (TEAC). The use of a winemaking process that included different maceration times and inoculation with yeasts, as well as spontaneous fermentation, significantly modulated the total phenolic content of the obtained wines and FP. This study could provide a good basis for the practical application and obtaining wines with a high content of phenolic compounds and antioxidant properties.

Eukaryotic probiotics currently attract a lot of scientific attention, with Saccharomyces cerevisiae and Saccharomyces boulardii being the most widely investigated probiotic yeasts. The range of yeast species with probiotic potential needs to be broadened. In this respect, juice-providing plants may diversify eukaryotic probiotic sources for organism preference. This study tested the probiotic potential of Pichia kudriavzevii and Kluyveromyces marxianus isolated from coconut juice and Schizosaccharomyces pombe and Wickherhamomyces anomalus isolated from raffia palm juice in Nigeria. The in vitro tests used the optical density method to assay the tolerance to acid (pH 2, 3, 5), alkaline (pH 7.5, 8.0), gastric juice (30%), bile (1, 2, and 3%), and osmotic pressure (5, 10, 15, 20, 25, and 30% glucose solution). All four yeasts survived in the test environments, exhibiting varying degrees of probiotic potential. After 96 h in simulated gastric juice, S. pombe outperformed K. marxianus and W. anomalus by 13 and 97.7% (p < 0.05), respectively. W. anomalus appeared to be the least viable in 30% gastric juice. After 96 h in the acid media, all yeasts performed better at pH 3.0 than at pH 2.0, with roughly 89% (1.695/0.185 mean absorbance values) greater growth in pH 3.0 than in pH 2.0. The alkaline media had a better effect on the growth rate. P. kudriavzevii fared best at pH 2.0 and 3.0 for up to 96 h. All yeasts maintained viability in 1, 2, and 3% bile solutions, although the growth rate did not improve significantly in any of the assay periods. Only minimal growth increase was registered in increased bile concentrations. All samples demonstrated sustained viability in 5–30% glucose between 24 and 48 h of incubation. After 48 h of incubation, the yeast concentrations began to fall as the glucose concentration rose from 5 to 30%. P. kudriavzevii was the least affected after 96 h (41.8%) and demonstrated the best survival results by the four criteria tested in this study. If this species meets all other non-assayed parameters which qualify a microorganism as a probiotic, P. kudriavzevii obtained from Nigerian coconut juice can be recommended as a potential source of commercial probiotics.

The aim of the study was to check the integument and alimentary tract of Theromyzon for the occurrence of fungi. Moreover, the mycological purity of water sources from which leeches were collected was analyzed. The potential role of the duck leech Theromyzon maculosum in transmitting pathogenic fungi has not been studied until now. Mycological analyses were performed according to the procedure approved in mycological diagnostic laboratories, using classical diagnostic methods (macro- and microcultures, microscopic observations). In total, 22 species of yeasts were detected. The specimens belong to eight genera: Candida, Citeromyces, Debaryomyces, Kluyveromyces, Lodderomyces, Pichia, Saccharomyces and Saccharomycodes. Overall, 18 species of fungi were isolated from leeches Theromyzon maculosum, including seven species from the integument and 11 species from the gastrointestinal system. Among fungi isolated from body integument, fungi of the genus Candida were dominant, whereas in the gastrointestinal system, the genus Saccharomyces dominated. From the river waters, nine fungi species were isolated, and yeasts of the genera Candida and Kluyveromyces dominated. Isolation of the same species of microfungi from the integument of leeches and the river water suggests that Theromyzon maculosum may be a potential vector of pathogenic yeasts for vertebrates living in the same ecosystems and for humans.

Information on the detection of the presence and potential for degradation of synthetic polymers (SPs) under various environmental conditions is of increasing interest and concern to a wide range of specialists. At this stage, there is a need to understand the relationship between the main participants in the processes of (bio)degradation of SPs in various ecosystems (reservoirs with fresh and sea water, soils, etc.), namely the polymers themselves, the cells of microorganisms (MOs) participating in their degradation, and humic substances (HSs). HSs constitute a macrocomponent of natural non-living organic matter of aquatic and soil ecosystems, formed and transformed in the processes of mineralization of bio-organic substances in environmental conditions. Analysis of the main mechanisms of their influence on each other and the effects produced that accelerate or inhibit polymer degradation can create the basis for scientifically based approaches to the most effective solution to the problem of degradation of SPs, including in the form of microplastics. This review is aimed at comparing various aspects of interactions of SPs, MOs, and HSs in laboratory experiments (in vitro) and environmental investigations (in situ) aimed at the biodegradation of polymers, as well as pollutants (antibiotics and pesticides) that they absorb. Comparative calculations of the degradation velocity of different SPs in different environments are presented. A special place in the analysis is given to the elemental chemical composition of HSs, which are most successfully involved in the biodegradation of SPs. In addition, the role of photo-oxidation and photoaging of polymers under the influence of the ultraviolet spectrum of solar radiation under environmental conditions on the (bio)degradation of SPs in the presence of HSs is discussed.

Coffee and coffee by-products contain several chemical compounds of great relevance, such as chlorogenic acid (CGA), trigonelline, and caffeine. Furthermore, yeasts have been the target of studies for their use as probiotics because of their interesting biochemical characteristics. The combined administration of probiotic microorganisms with components that provide health benefits mediated by alginate encapsulation is an alternative that ensures the stability of cells and chemical compounds. In this context, the aim of this work was to co-encapsulate the probiotic yeast Kluyveromyces lactis B10 and extracts of green coffee beans, coffee silverskin, and PVA (black, green or immature, and sour coffee beans). The bioactive composition, antioxidant and antimicrobial activities of the extracts, microcapsule morphological characteristics and encapsulation efficiency, ability of the encapsulation to protect the yeast cells subjected to gastrointestinal conditions, and antioxidant activity of the microcapsules were evaluated. All the evaluated extracts showed antioxidant activity, of which PVA showed 75.7% and 77.0%, green coffee bean showed 66.4% and 45.7%, and coffee silverskin showed 67.7% and 37.4% inhibition of DPPH and ABTS•+ radicals, respectively, and antimicrobial activity against the pathogenic bacteria E. coli, Salmonella, and S. aureus, with high activity for the PVA extract. The microcapsules presented diameters of between 1451.46 and 1581.12 μm. The encapsulation efficiencies referring to the yeast retention in the microcapsules were 98.05%, 96.51%, and 96.32% for green coffee bean, coffee silverskin, and PVA, respectively. Scanning electron microscopy (SEM) showed that the microcapsules of the three extracts presented small deformations and irregularities on the surface. The K. lactis cells encapsulated in all treatments with the extracts showed viability higher than 8.59 log CFU/mL, as recommended for probiotic food products. The addition of green coffee bean, coffee silverskin, and PVA extracts did not reduce the encapsulation efficiency of the alginate microcapsules, enabling a safe interaction between the extracts and the K. lactis cells.

The objective of this research was to investigate natural products for their potential against pathogenic microorganisms. Sabinene hydrate (SH), a monoterpenoid, is synthesised by numerous different plants as a secondary metabolite. At present, there is a lack of definite investigations regarding the antimicrobial activity of SH itself and its different isomers. The antimicrobial effects of commercially available SH (composed mainly of trans-isomer) were evaluated within a range of concentrations in three types of contact tests: solid and vapor diffusion and the macro-broth dilution method. Moreover, the effects of SH on the rate of linear growth and spore germination were also examined. Ethanolic SH solutions were tested against an array of microorganisms, including blue-stain fungi (Ceratocystis polonica, Ophiostoma bicolor, O. penicillatum), frequently originating from bark beetle galleries; three fungal strains (Musicillium theobromae, Plectosphaerella cucumerina, and Trichoderma sp.) isolated from a sapwood underneath bark beetle galleries (Ips typographus) on spruce (Picea abies) stems; Verticillium fungicola, isolated from diseased I. typographus larvae; two Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus), two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa); five yeasts (Candida albicans, C. krusei, C. parapsilosis, Saccharomyces cerevisiae, and Rhodotorula muscilaginosa), and two saprophytic fungi (Aspergillus niger and Penicillium notatum). In solid agar disc diffusion tests, Gram-positive bacteria exhibited greater susceptibility to SH than Gram-negative bacteria, followed by yeasts and fungi. The most resistant to SH in both the disc diffusion and broth macro-dilution methods were P. aeruginosa, A. niger, and Trichoderma sp. strains. Blue-stain fungi and fungi isolated from the Picea sapwood were the most resistant among the fungal strains tested. The minimum inhibition concentrations (MICs) generated by SH and determined using a disc volatilization method were dependent on the fungal species and played an important role in the development of microorganism inhibition. The two Gram-positive bacteria, B. subtilis and S. aureus (whose MICs were 0.0312 and 0.0625 mg/mL, respectively), were the organisms most susceptible to SH, followed by the Gram-negative bacterium, E. coli (MIC = 0.125 mg/mL) and two yeasts, C. albicans and C. kruei (MIC was 0.125 mg/mL and 0.25 mg/mL, respectively). C. parapsilosis (MIC = 0.75 mg/mL) was the yeast most resistant to SH. The investigation of antimicrobial properties of plant secondary metabolites is important for the development of a new generation of fungicides.

Plants and microbes share common metabolic pathways for producing a range of bioproducts that are potentially foundational to the future bioeconomy. However, in planta accumulation and microbial production of bioproducts have never been systematically compared on an economic basis to identify optimal routes of production. A detailed technoeconomic analysis of four exemplar compounds (4-hydroxybenzoic acid [4-HBA], catechol, muconic acid, and 2-pyrone-4,6-dicarboxylic acid [PDC]) is conducted with the highest reported yields and accumulation rates to identify economically advantaged platforms and breakeven targets for plants and microbes. The results indicate that in planta mass accumulation ranging from 0.1 to 0.3 dry weight % (dwt%) can achieve costs comparable to microbial routes operating at 40 to 55% of maximum theoretical yields. These yields and accumulation rates are sufficient to be cost competitive if the products are sold at market prices consistent with specialty chemicals ($20 to $50/kg). Prices consistent with commodity chemicals will require an order-of-magnitude-greater accumulation rate for plants and/or yields nearing theoretical maxima for microbial production platforms. This comparative analysis revealed that the demonstrated accumulation rates of 4-HBA (3.2 dwt%) and PDC (3.0 dwt%) in engineered plants vastly outperform microbial routes, even if microbial platforms were to reach theoretical maximum yields. Their recovery and sale as part of a lignocellulosic biorefinery could enable biofuel prices to be competitive with petroleum. Muconic acid and catechol, in contrast, are currently more attractive when produced microbially using a sugar feedstock. Ultimately, both platforms can play an important role in replacing fossil-derived products.

The Eurasian spruce bark beetle (Ips typographus) is currently the most economically relevant pest of Norway spruce (Picea abies). Ips typographus associates with filamentous fungi that may help it overcome the tree's chemical defenses. However, the involvement of other microbial partners in this pest's ecological success is unclear. To understand the dynamics of the bark beetle- associated microbiota, we characterized the bacterial and fungal communities of wild-collected and lab-reared beetles throughout their development by culture-dependent approaches, meta-barcoding, and quantitative PCR. Gammaproteobacteria dominated the bacterial communities, while the fungal communities were mainly composed of yeasts of the Saccharomycetales order. A stable core of microbes is shared by all life stages, and is distinct from those associated with the surrounding bark, indicating that Ips typographus influences the microbial communities of its environment and offspring. These findings coupled with our observations of maternal behavior, suggest that Ips typographus transfers part of itsmicrobiota to eggs via deposition of an egg plug treated with maternal secretions, and by inducing an increase in abundance of a subset of taxa from the adjacent bark. [ABSTRACT FROM AUTHOR]

Simple Summary: Endotoxemia in horses is a serious condition caused by diseases that result in systemic inflammation, such as colic, pleuropneumonia, metritis, etc., and can lead to death. Finding a treatment or prevention for this condition is of great importance for the health of horses. The β-glucans present in yeast, especially Saccharomyces cerevisia, are supplemented with nutritional properties that induce the modulation of the immune system. This study aims to evaluate whether supplementing horses' diets with β-glucans is capable of modulating horses' immune response to the inflammatory stimulus caused by the intravenous injection of endotoxins (E. coli lipopolysaccharide; 0.1 µg/kg/body weight). It was found that there is a positive interference with this supplementation, with evidence of the modulation of the immune system, which encourages its use as a dietary supplement in order to assist the immune response of horses in cases of endotoxemia. β-glucan is part of the cell wall of fungi and yeasts and has been known for decades to have immunomodulating effects on boosting immunity against various infections as a pathogen-associated molecular pattern that is able to modify biological responses. β-glucan has been used in rat models and in vitro studies involving sepsis and SIRS with good results, but this supplement has not been evaluated in the treatment of endotoxemia in horses. This study aims to evaluate the effects of preventive supplementation with β-glucan in horses submitted to endotoxemia by means of inflammatory response modulation. Eight healthy horses, both male and female, aged 18 ± 3 months, weighing 300 ± 100 kg of mixed breed, were randomly assigned to two groups of four animals, both of which were subjected to the induction of endotoxemia via the intravenous administration of E. coli lipopolysaccharides (0.1 µg/kg). For 30 days before the induction of endotoxemia, horses in the β-glucan group (GB) received 10 mg/kg/day of β-glucan orally, and horses in the control group (GC) received 10 mg/kg/day of 0.9% sodium chloride orally. The horses were submitted to physical exams, including a hematological, serum biochemistry, and peritoneal fluid evaluation, and the serum quantification of cytokines TNF-α, IL-6, IL-8, and IL-10. For statistical analysis, the normality of residues and homogeneity of variances were verified; then, the variables were analyzed as repeated measures over time, checking the effect of treatment, time, and the interaction between time and treatment. Finally, the averages were compared using Tukey's test at a significance level of 5%. Horses from both experimental groups presented clinical signs and hematological changes in endotoxemia, including an increase in heart rate and body temperature, neutrophilic leukopenia, an increase in serum bilirubin, glucose, lactate, and an increase in TNF-α, IL-6, and IL-10. Hepatic and renal function were not compromised by β-glucan supplementation. GB presented higher mean values of the serum total protein, globulins, and IL-8 compared to that observed in GC. In the peritoneal fluid, horses from GB presented a lower mean concentration of neutrophils and a higher mean concentration of macrophages compared to the GC. It was concluded that preventive supplementation of β-glucan for thirty days modulated the immune response, as evidenced by increasing serum total proteins, globulins, IL-8, and changes in the type of peritoneal inflammatory cells, without effectively attenuating clinical signs of endotoxemia in horses. Considering the safety of β-glucan in this study, the results suggest the potential clinical implication of β-glucan for prophylactic use in horse endotoxemia. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the fermentation performance of a Saccharomyces cerevisiae (Meyen ex E.C. Hansen) yeast strain with high alcoholigenous power during the vinification of Grillo and Nero d'Avola musts with high sugar concentration. The effects of such fermentations, conducted by means of FR-RS8 yeast strain, were evaluated through analyzing the fermentation kinetics, the chemical–physical parameters of musts and wines, and the volatile organic composition of the final wines. The sensory profiles of the obtained wines were also evaluated. Results highlighted that the FR-RS8 Saccharomyces cerevisiae yeast strain showed a great fermentation activity, suggesting an appreciable capability to overcome osmotic stress deriving from high sugar concentration musts, while the production of volatile acidity was moderate. Wines fermented by FR-RS8 yeast strain showed low content of higher alcohols, great amount of fermentation esters, and high content of free terpenes in both Grillo and Nero d'Avola wines. Sensory analysis highlighted that the aforementioned wines were very scented, complex, and structured, with good olfactory and gustatory persistence. [ABSTRACT FROM AUTHOR]

Yeast cells are often subjected to various types of weak acid stress in the process of industrial production, food processing, and preservation, resulting in growth inhibition and reduced fermentation performance. Under acidic conditions, weak acids enter the near-neutral yeast cytoplasm and dissociate into protons and anions, leading to cytoplasmic acidification and cell damage. Although some yeast strains have developed the ability to survive weak acids, the complexity and diversity of stresses during industrial production still require the application of appropriate strategies for phenotypes improvement. In this review, we summarized current knowledge concerning weak acid stress response and resistance, which may suggest important targets for further construction of more robust strains. We also highlight current feasible strategies for improving the weak acid resistance of yeasts, such as adaptive laboratory evolution, transcription factors engineering, and cell membrane/wall engineering. Moreover, the challenges and perspectives associated with improving the competitiveness of industrial strains are also discussed. This review provides effective strategies for improving the industrial phenotypes of yeast from multiple dimensions in future studies. [ABSTRACT FROM AUTHOR]

Oxidoreductase (OXR) enzymes are in high demand for biocatalytic applications in the food industry and cosmetics (glucose oxidase (GOx) and cellobiose dehydrogenase (CDH)), bioremediations (horseradish peroxidase (HRP) and laccase (LAC)), and medicine for biosensors and miniature biofuel cells (GOx, CDH, LAC, and HRP). They can be used in a soluble form and/or within the yeast cell walls expressed as chimeras on the surface of yeast cells (YSD), such as P. pastoris and S. cerevisiae. However, most of the current studies suffer from either low yield for soluble enzyme expression or low enzyme activity when expressed as chimeric proteins using YSD. This is always the case in studies dealing with the heterologous expression of oxidoreductase enzymes, since there is a requirement not only for multiple OXR gene integrations into the yeast genome (super transformations), and codon optimization, but also very careful design of fermentation media composition and fermentation conditions during expression due to the need for transition metals (copper and iron) and metabolic precursors of FAD and heme. Therefore, scientists are still trying to find the optimal formula using the above-mentioned approaches; most recently, researcher started using protein engineering and directed evolution to increase in the yield of recombinant enzyme production. In this review article, we will cover all the current state-of-the-art technologies and most recent advances in the field that yielded a high expression level for some of these enzymes in specially designed expression/fermentation systems. We will also tackle and discuss new possibilities for further increases in fermentation yield using cutting-edge technologies such as directed evolution, protein and strain engineering, high-throughput screening methods based on in vitro compartmentalization, flow cytometry, and microfluidics. [ABSTRACT FROM AUTHOR]

Mare milk is consumed by approximatively 30 million people in the world. In countries in Asia and East Europe, mare milk is mainly consumed as source of fermented products, called koumiss, airag or chigee, alcoholic beverages obtained by means of a culture of bacteria and lactose-fermenting yeasts. Recent research concerning mare milk and its derivatives deals mainly with their potential employment for human health. Studies about the isolation and characterization of Lactobacillus spp. and yeasts from koumiss have been aimed at assessing the potential functional properties of these micro-organisms and to find their employment for the industrial processing of mare milk. The aim of this literature review is to summarize recent research about microorganisms in fermented mare milk products and their potential functional properties. [ABSTRACT FROM AUTHOR]

Foods consumed raw, such as lettuce, can host food-borne human-pathogenic bacteria. In the worst-case, these diseases cause to death. To limit illness and industrial losses, one innovative sanitation method is non-thermal plasma, which offers an extremely efficient reduction of living microbial biomass. Unfortunately, the total viable count (TVC), one of the most common methods for quantifying antimicrobial effects, provides no detailed insights into the composition of the surviving microbial community after treatment. To address this information gap, different special agars were used to investigate the reduction efficiency of plasma-treated water (PTW) on different native cultivable microorganisms. All tested cultivable microbial groups were reduced using PTW. Gram-negative bacteria showed a reduction of 3.81 log10, and Gram-positive bacteria showed a reduction of 3.49 log10. Fungi were reduced by 3.89 log10. These results were further validated using a live/dead assay. MALDI-ToF (matrix-assisted laser-desorption-ionization time-of-flight)-based determination was used for a diversified overview. The results demonstrated that Gram-negative bacteria were strongly reduced. Interestingly, Gram-positive bacteria and fungi were reduced by nearly equal amounts, but could still recover from PTW treatment. MALDI-ToF mainly identified Pseudomonas spp. and groups of Bacillus on the tested lettuce. These results indicate that the PTW treatment could efficiently achieve a ubiquitous, spectrum-wide reduction of microbial life. [ABSTRACT FROM AUTHOR]

Degradation, detoxification, or removal of the omnipresent polycyclic aromatic hydrocarbons (PAHs) from the ecosphere as well as their prevention from entering into food chain has never appeared simple. In this context, cost-effective, eco-friendly, and sustainable solutions like microbe-mediated strategies have been adopted worldwide. With this connection, measures have been taken by multifarious modes of microbial remedial strategies, i.e., enzymatic degradation, biofilm and biosurfactant production, application of biochar-immobilized microbes, lactic acid bacteria, rhizospheric-phyllospheric-endophytic microorganisms, genetically engineered microorganisms, and bioelectrochemical techniques like microbial fuel cell. In this review, a nine-way directional approach which is based on the microbial resources reported over the last couple of decades has been described. Fungi were found to be the most dominant taxa among the CPAH-degrading microbial community constituting 52.2%, while bacteria, algae, and yeasts occupied 37.4%, 9.1%, and 1.3%, respectively. In addition to these, category-wise CPAH degrading efficiencies of each microbial taxon, consortium-based applications, CPAH degradation–related molecular tools, and factors affecting CPAH degradation are the other important aspects of this review in light of their appropriate selection and application in the PAH-contaminated environment for better human-health management in order to achieve a sustainable ecosystem. [ABSTRACT FROM AUTHOR]

It was aimed to isolate Saccharomyces cerevisiae strains from 18 traditional sourdough samples collected from 3 different provinces (Aksaray, Niğde, and Konya), and to conduct the genotypic characterization and population analyses using different DNA markers. In total, 58 of the 72 endogenous yeasts were identified as S. cerevisiae. In determining intraspecific genetic variation, SCoT 13 primer gave more useful results than iPBS and ISSR primers. As the distance between populations increased, the degree of genetic distance also increased (R = 0.74). The degree of genetic variation between populations (16%) and within populations (84%) was found to be statistically significant (P<0.001). Strains were divided into many subgroups on the UPGMA dendrogram, and according to STRUCTURE analysis, the number of significant subgroups was two (ΔK = 2). According to UPGMA and PCoA, clustering did not occur according to the regions where the strains were isolated, and random distribution was observed. [ABSTRACT FROM AUTHOR]

The ecosystem's biodiversity and soil microorganisms are impacted by the increasing use of synthetic fertilizers and pesticides, which causes soil acidity and limits the sustainability of agricultural output. The majority of microbial functions in acidic soil are inhibited because of decreasing nutrient cycling and organic matter decomposition as well as diminishing bacterial and fungal growth and reproduction. In light of these growing concerns, the use of microorganisms as bio fertilizers is a recommended as alternative agricultural practice. Recent times have brought about a change in the paucity of study on yeasts and their ability to safely boost plant growth. Numerous works on bacteria have been made available. The primary objective of the study is to highlight the widespread application of yeasts in sustainable agricultural practices to promote plant growth in acidic soils. All of the advantages that yeasts provide may contribute to the growth of plants. Therefore, a thorough investigation into yeasts may be fruitful and offer a sustainable means of boosting agricultural yields that are necessary in acidic soil. [ABSTRACT FROM AUTHOR]

Background: Mild Colombian coffees are recognized worldwide for their high-quality coffee cup. However, there have been some failures in post-harvest practices, such as coffee grain fermentation. These failures could occasionally lead to defects and inconsistencies in quality products and economic losses for coffee farmers. In Colombia, one of the fermentation methods most used by coffee growers is wet fermentation, conducted by submerging the de-pulped coffee beans for enough time in water tanks to remove the mucilage. Objectives: We evaluated the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours) on the total number of microbial groups. We also identified microorganisms of interest as starter cultures. Methods: We used a completely randomized experimental design with two factors; the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours), for 9 treatments with two replicates. During the coffee fermentation (1,950 g), the pH and °Brix were monitored. Total counts of different microbial groups (mesophiles, coliforms, lactic-acid bacteria, acetic-acid bacteria, and yeasts) were performed. Various isolates of microorganisms of interest as starter cultures (lactic-acid bacteria and yeasts) were identified using molecular sequencing techniques. Results: 21 lactic-acid bacteria (LAB) isolates and 22 yeasts were obtained from the different mini-batch fermentation systems. The most abundant lacticacid bacteria species found were Lactiplantibacillus plantarum (46%) and Levilactobacillus brevis (31%). Pichia kluivery (39%) and Torulaspora delbrueckii (22%) were the most abundant yeast species. Conclusion The studied factors did not have effect over the microorganism's development. The identified bacterial and yeasts species have potential as starter cultures for better-quality coffees and in fermentation-related applications. [ABSTRACT FROM AUTHOR]

5-Hydroxymethfurural (5-HMF) is naturally found in a variety of foods and beverages and represents a main inhibitor in the lignocellulosic hydrolysates used for fermentation. This study investigated the impact of 5-HMF on the genomic stability and phenotypic plasticity of the yeast Saccharomyces cerevisiae. Using next-generation sequencing technology, we examined the genomic alterations of diploid S. cerevisiae isolates that were subcultured on a medium containing 1.2 g/L 5-HMF. We found that in 5-HMF-treated cells, the rates of chromosome aneuploidy, large deletions/duplications, and loss of heterozygosity were elevated compared with that in untreated cells. 5-HMF exposure had a mild impact on the rate of point mutations but altered the mutation spectrum. Contrary to what was observed in untreated cells, more monosomy than trisomy occurred in 5-HMF-treated cells. The aneuploidy mutant with monosomic chromosome IX was more resistant to 5-HMF than the diploid parent strain because of the enhanced activity of alcohol dehydrogenase. Finally, we found that overexpression of ADH6 and ZWF1 effectively stabilized the yeast genome under 5-HMF stress. Our findings not only elucidated the global effect of 5-HMF on the genomic integrity of yeast but also provided novel insights into how chromosomal instability drives the environmental adaptability of eukaryotic cells. [ABSTRACT FROM AUTHOR]

Strains of the ascomycetous yeast Metschnikowia pulcherrima isolated from the internal tissues of fruits were evaluated for phytohormonal activity. IAA production in the culture liquid was determined by the chromatographic method (HPLC-UV). The production of the phytohormones zeatin and gibberellin (GA3) in the culture liquid was determined by a chromatographic method using a quadrupole time-of-flight mass spectrometry detector (Q- TOF LC / MS). IAA and zeatin were detected in the culture liquid of all strains studied. Synthesis of gibberellin (GA3) was detected in only 5 of 18 strains examined. On average, the strains showed the highest activity in the synthesis of IAA (6.668 µg/mL and 2.135 mg/g). Zeatin content was 3 orders of magnitude lower (0.365 ng/mL and 0.129 µg/g) and GA3 content was 4 orders of magnitude lower (0.076 ng/mL and 0.027 µg/g). According to our results, the yeast M. pulcherrima is not an active producer of zeatin and GA3 in amounts relevant to the plant. On the other hand, the average level of IAA synthesis detected in M. pulcherrima strains in this study is within the range of concentrations that can stimulate plant development and growth. Thus, endophytic strains of M. pulcherrima that produce plant-relevant levels of IAA could be improved to increase their synthesis ability and used as plant growth promoters in agricultural crops. [ABSTRACT FROM AUTHOR]

This paper evaluates the effects of an alternative hopping technique, called dip hopping, on beer. This technique involves infusing hops in hot water (or in a portion of wort) and subsequently combining the infusion with the wort (after wort cooling) directly in the fermenter when the yeast is added for fermentation. The reference beers were produced employing the "traditional" late hopping technique, and the experimental beers were produced using the dip hopping technique. A variety of hops with a significant concentration of essential oil and a strain of yeast with high β-glucosidic activity capable of releasing aromatic molecules from precursors supplied by hops were used. The samples were analysed in terms of alcohol content, degree of attenuation, colour, and bitterness. Sensory analysis and gas chromatography analysis were also performed. The data showed statistically significant differences between the reference beers and the experimental beers, with the latter featuring greater hints of citrus, fruity, floral, and spicy aromas. As an overall effect, there was an increase in the olfactory and gustatory pleasantness of the beers produced with the dip hopping technique. [ABSTRACT FROM AUTHOR]

This paper focuses on a selection of microorganisms that should eventually form a Defined Consortium of Wine Microorganisms. The Consortium might serve as a sophisticated oenological product for the production of wine with attractive organoleptic features. The Defined Consortium of Wine Microorganisms was obtained from non-saccharomyces and saccharomyces yeasts and lactic acid bacteria isolated from places where autochthonous microflora can be expected to occur (grape berries, wine lees or cellar spaces). A total of 42 microorganisms were obtained by surface smears, fallouts from the air or isolation from fermented must. All isolates were then tested and the best strains were selected on the basis of technological and phenotypic characterisation using standard microbiological techniques. The main criteria for the selection of strains were the ability to ferment and the production of organoleptically active compounds. Sulphur dioxide or ethanol tolerance, ß-glucosidase activity, a taxonomic identification, the tendency to produce sulphane or the ability of lactic acid bacteria to perform malolactic fermentation were also considered. According to these results, the non-saccharomyces yeast Starmerella bacillaris, the saccharomyces yeast Saccharomyces cerevisiae and the lactic acid bacterium Levilactobacillus brevis were selected as part of the Defined Consortium of Wine Microorganisms. [ABSTRACT FROM AUTHOR]

The textile industry produces high amounts of effluents containing synthetic dyes that are recalcitrant and potentially hazardous to the environment, being azo dyes one of the most commonly used classes. Biological methods for dye degradation are promising, but knowledge of the toxicity of the resulting products is key for assessing their safety discharge on the environment. The present study investigated the potential toxicity of simulated effluents with dyes commonly used in the textile industry (reactive, direct, and basic groups). These effluents were treated by yeasts Candida parapsilosis (HOMOGS20B), Candida pseudoglaebosa (LIIIS36B), and Yarrowia lipolytica (HOMOGST27AB) after which their toxicity was assessed using three different assays in order to represent different trophic levels. Mutagenicity was also evaluated. C. pseudoglaebosa (LIIIS36B) was the most effective, completely decolorizing four of the five simulated effluents. Degradation products resulting from the yeast treatment were detected in the supernatant of the treated effluents and could be aromatic amines. Although the toxicity of the original simulated effluents was high, treated effluents demonstrated a decrease in toxicity and none exhibit mutagenicity. This work shows that the three selected yeasts could have a high potential for dye removal from textile wastewaters without generating toxic end-products, thus being an environmentally safe biological method. [ABSTRACT FROM AUTHOR]

Phytopathogenic filamentous fungi are main producers of mycotoxins and contaminants of the grain in silos. Although several yeast and lactic acid bacteria (LAB) species are known to inhibit mycelial growth and production of mycotoxins, the diversity of fungi and the mechanisms of mycotoxin production, impose the development of new bioproducts for protection of crop plants and harvested cereals. The present work focuses on the complex characterization as biocontrol agents of 15 strains belonging to five yeast (Ogataea polymorpha, Pichia kudriavzevii, Candida parapsilosis and Saccharomyces cerevisiae) and, respectively, to eight LAB (Lactobacillus rhamnosus, L. plantarum, L. paracasei, Enterococcus faecalis) species from artisan fermented milk, sour-crème, cheese and yogurt. The mycelial growth inhibition tests against Aspergillus flavus and Aspergillus ochraceus strains, revealed values of mycelial growth inhibition index between 60 and 100%, depending on the culture media used for co-cultivation. The semi-quantitative determination of aflatoxins and ochratoxin A (Thin Layer Chromatography) proved that P. kudriavzevii L3S and SM3, respectively, L. plantarum S2B and E. faecalis U4, also interfered with mycotoxin synthesis. In conclusion, all the tested yeast and LAB strains showed complex antifungal activities representing a promising basis for the development of alternative strategies aimed to prevent fungal contamination of crops. [ABSTRACT FROM AUTHOR]

Biotechnological processes, particularly those involved in biosurfactant production, can pose significant financial challenges. The viability of biosurfactant production hinges on the creation of processes that make use of cost-effective raw materials. This study focuses on exploring the potential of Candida lipolytica ICCF 214 (ATCC 16618) reference strain for biosurfactant production using a mixture of vegetable oil and other chemical compounds used for fermentation medium (1% glutamic acid, urea, or glucose) as carbon sources. Based on the obtained results, we can conclude that all three fermentation media stimulated Candida lipolytica ICCF 214 strain to produce biosurfactants, but further analysis of surface tension and antimicrobial activity of the obtained biosurfactants is required. Additionally, we observed that media with a volume of 100 ml produced higher quantities of biosurfactants, due to the good aeration of the fermentation medium. However, even the ones with 150 ml showed decent performance during the bioprocess. [ABSTRACT FROM AUTHOR]

AbstractIn humans, exogenous antioxidants aid the endogenous antioxidant system to detoxify excess ROS generated during oxidative stress, thereby protecting the body against various diseases and stressful conditions. The majority of natural antioxidants available on the consumer market are plant-based; however, fungi are being recognized as alternative sources of various natural antioxidants such as polysaccharides, pigments, peptides, sterols, phenolics, alkaloids, and flavonoids. In addition, some exogenous antioxidants are exclusively found in fungi. Fungi-derived antioxidants exhibit scavenging activities against DPPH, ABTS, hydroxyl, superoxide, hydrogen peroxide, and nitric oxide radicals in vitro. Furthermore, in vivo models, application of fungal-derived antioxidants increase the level of various antioxidant enzymes, such as catalases, superoxide dismutases, and glutathione peroxidases, and reduce the level of malondialdehyde. Therefore, fungi-derived antioxidants have potential to be used in the food, cosmetic, and pharmaceutical industries. This review summarizes the antioxidant potential of different fungi (mushrooms, yeasts, and molds)-derived natural compounds such as polysaccharides, pigments, peptides, ergothioneine, ergosterol, phenolics, alkaloids, etc. [ABSTRACT FROM AUTHOR]

In Southwestern Colombia, cocoa clones are cultivated in which productivity characteristics predominate over bean quality. In this study, cocoa beans of the CCN-51 clone harvested in the Tumaco region (Nariño, Colombia) were fermented following four different treatments: (1) spontaneously (at room temperature for 120 h) in traditional conditions (Control); (2) traditional processing with a pre-drying (sun-dried for 24 h) treatment (PD); (3) with fermentation (for 120 h) after inoculation of a yeast starter culture (YS); and (4) including both treatments, pre-drying and yeast inoculation (PD + YS). Chemical composition, fatty acids, total polyphenol, methylxanthines (theobromine and caffeine) and lactic acid content of cocoa beans were determined. Chemical and fatty acid composition and theobromine content were not affected by the different fermentation treatments applied (p > 0.05). When analyzing total polyphenol content, YS (16.62 mg/g) and PD + YS (17.74) treatments significantly decreased (p < 0.05) the content of these compounds at the end of the fermentation process, affecting cocoa flavour, while PD treatment decreased (p < 0.05) the caffeine content (0.68 mg/g) of cocoa beans. Finally, lactic acid content decreased because of both inoculation of yeast starter (1.11 mg/g) and mainly the pre-drying treatment (0.60). In conclusion, solar pre-drying in the open air and the inoculation of yeast starter treatments could improve the final quality of cocoa beans. [ABSTRACT FROM AUTHOR]

Aquatic animals are continually being exposed to stressors under farming conditions, increasing risks to gut health that result in dysbiosis. Since restrictions are imposed on the frequent use of antibiotics in aquaculture, there is emerging demand for economically viable, environmentally safe, and sustainable alternatives for the intensive production of aquaculture species. The application of beneficial microorganisms as probiotics has been suggested and widely practiced in recent times. Bacteria and fungi are ubiquitous microorganisms that can grow in various environments where organic substrates are available. Being rich in nutrients, a fish's aquatic environment and gastrointestinal tract confer a favorable culture milieu for the microorganisms. However, the colonization and probiotic potential of fungi and mycelial bacteria resembling fungi (actinobacteria), either in the culture environment or within the gastrointestinal tracts of fish, have received less emphasis. Apart from bacilli and lactic acid bacteria, as the most conventionally used probiotics in aquaculture, numerous studies have focused on other promising alternatives. Diverse species of yeasts and molds belonging to the kingdom 'Fungi' have been characterized for their prospective roles in nutrition, immunomodulation, and disease prevention in fish. Bioactive compounds such as manno-oligosaccharides and β-glucans are recognized as fungal postbiotics that improve innate immunity and disease resistance in fish. Actinobacteria are known to possess different hydrolytic enzymes and novel secondary metabolites representing their probiotic attributes. The application of these groups in water quality amelioration has also been explored. Thus, this paper presents an overview of the present status of knowledge pertaining to the effects of yeasts (Candida, Cryptococcus, Debaryomyces, Geotrichum, Leucosporidium, Pichia, Rhodosporidium, Rhodotorula, Saccharomyces, Sporidiobolus, Sporobolomyces, Trichosporon and Yarrowialipolytica), molds (Aspergillus spp.) and actinobacteria (Streptomyces) as probiotics in finfish aquaculture, as well as their occurrence within the gastrointestinal tracts of finfish. Furthermore, probiotic mechanisms, selection criteria, and future perspectives on using fungi and actinobacteria as promising probiotics are discussed. [ABSTRACT FROM AUTHOR]

A novel fermented dairy drink utilizing microbial strains displaying potential probiotic attributes was formulated. The study constituted several experimental cohorts, including Lactiplantibacillus plantarum AB6‐25, isolated from a human stool sample; Lacticaseibacillus casei K2, sourced from a koumiss sample; Lacticaseibacillus rhamnosus 3B7, derived from a traditional yogurt sample; and identical lactic acid bacteria (LAB) in combination with yeast (Saccharomyces boulardii T8‐3C from chicken feces) strains. Two distinct iterations of probiotic‐fermented dairy drinks were generated by introducing subcultured microorganism cultures: LAB strains at a concentration of 1% each (designated as combination A) and a blend of LAB strains at 1% each along with T8‐3C at 0.5% (designated as combination B) into both whole and semi‐skimmed milk matrices. The fermentation process persisted until the pH reached 4.6 under constant conditions of 37 ± 1°C. Subsequently, the samples were held at 4 ± 1°C for 15 days. The groups' physicochemical, microbiological, and sensory characteristics were determined on days 1, 8, and 15 of storage, and the protein profile was determined. Standardized regression analysis and principal component analysis evaluated the results. Fat content affected the changes in dry matter. pH decreased in all samples during storage, particularly in the yeast group. The microorganism group positively affected syneresis, whereas fat content and the interaction of fat content and the microorganism group had a negative effect. The most critical factor in the decrease in syneresis was the increase in fat content. LAB and yeasts maintained their probiotic effects during storage, with a viability level of approximately 109 and 108 cfu/mL, respectively. [ABSTRACT FROM AUTHOR]

The aim of the study was to check the integument and alimentary tract of Theromyzon for the occurrence of fungi. Moreover, the mycological purity of water sources from which leeches were collected was analyzed. The potential role of the duck leech Theromyzon maculosum in transmitting pathogenic fungi has not been studied until now. Mycological analyses were performed according to the procedure approved in mycological diagnostic laboratories, using classical diagnostic methods (macro- and microcultures, microscopic observations). In total, 22 species of yeasts were detected. The specimens belong to eight genera: Candida , Citeromyces , Debaryomyces , Kluyveromyces , Lodderomyces , Pichia , Saccharomyces and Saccharomycodes. Overall, 18 species of fungi were isolated from leeches Theromyzon maculosum , including seven species from the integument and 11 species from the gastrointestinal system. Among fungi isolated from body integument, fungi of the genus Candida were dominant, whereas in the gastrointestinal system, the genus Saccharomyces dominated. From the river waters, nine fungi species were isolated, and yeasts of the genera Candida and Kluyveromyces dominated. Isolation of the same species of microfungi from the integument of leeches and the river water suggests that Theromyzon maculosum may be a potential vector of pathogenic yeasts for vertebrates living in the same ecosystems and for humans. [Display omitted] • Fungi of Theromyzon maculosum. • Genus Candida and Saccharomyces. • Leeches as vector of pathogenic yeasts. [ABSTRACT FROM AUTHOR]

Yeasts have been widely used as a model to better understand cell cycle mechanisms and how nutritional and genetic factors can impact cell cycle progression. While nitrogen scarcity is well known to modulate cell cycle progression, the relevance of nitrogen excess for microorganisms has been overlooked. In our previous work, we observed an absence of proper entry into the quiescent state in Hanseniaspora vineae and identified a potential link between this behavior and nitrogen availability. Furthermore, the Hanseniaspora genus has gained attention due to a significant loss of genes associated with DNA repair and cell cycle. Thus, the aim of our study was to investigate the effects of varying nitrogen concentrations on H. vineae's cell cycle progression. Our findings demonstrated that nitrogen excess, regardless of the source, disrupts cell cycle progression and induces G2/M arrest in H. vineae after reaching the stationary phase. Additionally, we observed a viability decline in H. vineae cells in an ammonium‐dependent manner, accompanied by increased production of reactive oxygen species, mitochondrial hyperpolarization, intracellular acidification, and DNA fragmentation. Overall, our study highlights the events of the cell cycle arrest in H. vineae induced by nitrogen excess and attempts to elucidate the possible mechanism triggering this absence of proper entry into the quiescent state. Take‐away: High concentrations of nitrogen inhibit proper quiescent arrest in Hanseniaspora vineae.The decline in viability of yeast is ammonium‐dependent.Ammonium excess leads to an increase in reactive oxygen species and mitochondrial hyperpolarization.Ammonium excess triggers intracellular acidification and DNA damage. [ABSTRACT FROM AUTHOR]

Investigating bovine and ovine mycotic mastitis was the study's goal. A total of 250 milk samples were collected from cows, ewes and does suffering from mastitis, not responding for antibiotic therapy, to determine the prevalence of fungal pathogens associated with mastitis. For the isolated yeasts, antimicrobial susceptibility testing was done through disc diffusion method, and biofilm formation was evaluated phenotypically by cultivation on Congo Red Agar (CRA) medium. Also, MDR1, CDR and ERG11 genes were detected by PCR. Out of the collected milk samples, 53 samples (21.2%) were positive for the presence of fungal pathogens. Out of them, 54 fungal pathogens were recovered, including 49 Candida species, 2 A. niger, in addition to one of A. fumigatus, A. flavus and Penicillium species. The yeast isolates included 18 C. guilliermondii, 16 C. parapsilosis, 7 C. tropicalis, 4 C. albicans, and 4 C. kefyr. Antimicrobial susceptibility testing of Candida isolates showed that all isolates were resistant to nystatin. Regarding to fluconazole, 25 isolates were sensitive, 2 isolates were intermediately sensitive and 22 isolates were resistant. Nine yeast isolates were biofilm former. All tested isolates harbored MDR1 gene, 4 isolates contained CDR gene and only 1 isolate was positive for ERG11 gene. [ABSTRACT FROM AUTHOR]

Mycoparasites in Basidiomycota comprise a diverse group of fungi, both morphologically and phylogenetically. They interact with their hosts through either fusion-interaction or colacosome-interaction. Colacosomes are subcellular structures formed by the mycoparasite at the host-parasite interface, which penetrate the parasite and host cell walls. Previously, these structures were detected in 19 fungal species, usually by means of transmission electron microscopy. Most colacosome-forming species have been assigned to Microbotryomycetes (Pucciniomycotina, Basidiomycota), a highly diverse class, comprising saprobic yeasts, mycoparasites, and phytoparasites. In general, these myco- and phytoparasites are dimorphic organisms, with a parasitic filamentous morph and saprobic yeast morph. We investigated colacosome-forming mycoparasites based on fungarium material, freshly collected specimens, and cultures of yeast morphs. We characterised the micromorphology of filamentous morphs, the physiological characteristics of yeast morphs, and inferred phylogenetic relationships based on DNA sequence data from seven loci. We outline and employ an epifluorescence-based microscopic method to assess the presence and organisation of colacosomes. We describe five new species in the genus Colacogloea, the novel dimorphic mycoparasite Mycogloiocolax gerardii, and provide the first report of a sexual, mycoparasitic morph in Colacogloea philyla and in the genus Slooffia. We detected colacosomes in eight fungal species, which brings the total number of known colacosome-forming fungi to 27. Finally, we revealed three distinct types of colacosome organisation in Microbotryomycetes. [ABSTRACT FROM AUTHOR]

The union of aquaculture and hydroponics is named aquaponics—a system where microorganisms, fish and plants coexist in a water environment. Bacteria are essential in processes which are fundamental for the functioning and equilibrium of aquaponic systems. Such processes are nitrification, extraction of various macro- and micronutrients from the feed leftovers and feces, etc. However, in aquaponics there are not only beneficial, but also potentially hazardous microorganisms of fish, human, and plant origin. It is important to establish the presence of human pathogens, their way of entering the aforementioned systems, and their control in order to assess the risk to human health when consuming plants and fish grown in aquaponics. Literature analysis shows that aquaponic bacteria and yeasts are mainly pathogenic to fish and humans but rarely to plants, while most of the molds are pathogenic to humans, plants, and fish. Since the various human pathogenic bacteria and fungi found in aquaponics enter the water when proper hygiene practices are not applied and followed, if these requirements are met, aquaponic systems are a good choice for growing healthy fish and plants safe for human consumption. However, many of the aquaponic pathogens are listed in the WHO list of drug-resistant bacteria for which new antibiotics are urgently needed, making disease control by antibiotics a real challenge. Because pathogen control by conventional physical methods, chemical methods, and antibiotic treatment is potentially harmful to humans, fish, plants, and beneficial microorganisms, a biological control with antagonistic microorganisms, phytotherapy, bacteriophage therapy, and nanomedicine are potential alternatives to these methods. [ABSTRACT FROM AUTHOR]

Background: Mild Colombian coffees are recognized worldwide for their high-quality coffee cup. However, there have been some failures in post-harvest practices, such as coffee grain fermentation. These failures could occasionally lead to defects and inconsistencies in quality products and economic losses for coffee farmers. In Colombia, one of the fermentation methods most used by coffee growers is wet fermentation, conducted by submerging the de-pulped coffee beans for enough time in water tanks to remove the mucilage. Objectives: We evaluated the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours) on the total number of microbial groups. We also identified microorganisms of interest as starter cultures. Methods: We used a completely randomized experimental design with two factors; the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours), for 9 treatments with two replicates. During the coffee fermentation (1,950 g), the pH and °Brix were monitored. Total counts of different microbial groups (mesophiles, coliforms, lactic-acid bacteria, acetic-acid bacteria, and yeasts) were performed. Various isolates of microorganisms of interest as starter cultures (lactic-acid bacteria and yeasts) were identified using molecular sequencing techniques. Results: 21 lactic-acid bacteria (LAB) isolates and 22 yeasts were obtained from the different mini-batch fermentation systems. The most abundant lactic-acid bacteria species found were Lactiplantibacillus plantarum (46%) and Levilactobacillus brevis (31%). Pichia kluivery (39%) and Torulaspora delbrueckii (22%) were the most abundant yeast species. Conclusion The studied factors did not have effect over the microorganism’s development. The identified bacterial and yeasts species have potential as starter cultures for better-quality coffees and in fermentation-related applications.

Abstract Mannoproteins (MPs) originate from yeast cells and can play important roles in maintaining wine stability and modulating wine organoleptic properties. Due to their natural presence in wines, MP products are allowed to be used as enological additives in wine industry. To guarantee an appropriate application of these products during winemaking, it is necessary for both researchers and winemakers to understand the mechanisms of MPs as multifunctional organoleptic modulators. This review has introduced the current state of knowledge of the researches focus on the application of different MP products in red wines and also the interactions between MPs and wine sensory active components (polyphenols, aroma compounds) in model wine solutions. We have summarized the possible mechanisms of MPs that affect the color, astringency, and aroma of red wines and the relationship between the physicochemical characteristics and functionalities of MPs. Besides, development trends of MP products are also discussed. It seems that yeast biomass, especially those from non‐Saccharomyces yeasts show good potential in producing large quantities of MPs, an appropriate combination of yeast cultivation and preservation methods with extraction and purification techniques may obtain MPs of ideal production, purity, and functionality in an industrial scale, which should be put more efforts by both scientists and manufacturers in the future.

The purpose of the study was to compare cytological samples from two consecutive swabs obtained from ear canals of dogs with otitis externa and to determine the minimum number of samples required to obtain up-to-date information on the degree of microbiological contamination of the affected ear canals. Samples were obtained using sterile applicators with a cotton tip, which were sequentially inserted into ear canal until slight resistance (the junction between vertical and horizontal parts of ear canal), after making a circular motion, the applicator was removed and the material from the tip was applied to the glass slide with rolling movements so that on each slide there were four single parallel smears - two from each ear of the dog. The slides were air dried for one hour and stained using the standard Diff-Quick method. The actual counting was carried out at 1000 magnification (at a high magnification field). Bacteria were differentiated according to their shape into cocci and bacilli. The numbers of bacteria and fungi in the two samples were compared using the Wilcoxon matched pair test. Qualitative agreement between two consecutive swabs was determined using the k-test. Among the studied animals, a breed predisposition to otitis externa was revealed in Cocker Spaniels and French Bulldogs, and an anatomical predisposition in animals with drooping auricles. There was no significant difference in the number of microorganisms present in two ear cytology samples taken consecutively from the same ear at the same site in the external auditory canal, and there was significant agreement between the results of two consecutive smears for the presence of cocci and rods. For yeast, the agreement was only moderate. The data obtained indicate that in cases of otitis externa in dogs, reproducibility of cytological pattern with a single sample of material, as a rule, reflects current stage of pathogenesis of the disease and provides the best opportunity to detect local proliferative activity of opportunistic microbiota and corresponding inflammatory response of the macroorganism.

Marine fungi are important sources of new metabolites including certain enzymes of medical interest due to their enormous capacity to adapt themselves to extreme environments. Living in a highly competitive ecological niche, they produce certain unusual chemical moieties. Marine biological resources are green, abundant, renewable and aid in economic development. The present study investigates the production of L-Glutaminase which is of therapeutic and industrial importance, from marine fungi of coastal Karnataka. Primary screening on agar plates and submerged fermentation in broth was employed for enzyme production. Both marine yeasts (Pichia sp) and filamentous fungal strains (Aspergillus, Penicillium) were found to be efficient producers of L-Glutaminase. Of the 42 isolates, five potential strains were selected through primary screening and Thin Layer Chromatography was performed to confirm the production. Filamentous fungi were identified through morphological and molecular methods as Penicillium and Aspergillus strains with 99-100% similarity. A. foveolatus (MT667385)and A. nidulans (MT667422) were potential producers (1.58U/ml and 1.41IU/ml). The yeast identified was Pichia kudriavzevii (MT667428), which was a moderate producer of Glutaminase and first marine yeast reported for this enzyme production. Neosartorya quadricincta (MT667427) and P. citrinum (MT667426) are also moderate producers. After screening the marine fungi, the isolated strains’ potential to produce L-Glutaminase was confirmed using SDS PAGE, FTIR and Mass analysis. This study emphasizes the necessity of marine fungal culturing and the scope of use of these fungi for further commercial production of L-Glutaminase which would uplift marine economy.

Kombucha is an increasingly popular functional beverage that has gained attention for its unique combination of phytochemicals, metabolites, and microbes. Previous chemical and microbial composition analyses of kombucha have mainly focused on understanding their changes during fermentation. Very limited information is available regarding nutrient profiles of final kombucha products in the market. In this study, we compared the major chemicals (tea polyphenols, caffeine), antioxidant properties, microbial and metabolomic profiles of nine commercial kombucha products using shotgun metagenomics, internal transcribed spacer sequencing, untargeted metabolomics, and targeted chemical assays. All of the nine kombucha products showed similar acidity but great differences in chemicals, metabolites, microbes, and antioxidant activities. Most kombucha products are dominated by the probiotic Bacillus coagulans or bacteria capable of fermentation including Lactobacillus nagelii, Gluconacetobacter, Gluconobacter, and Komagataeibacter species. We found that all nine kombuchas also contained varying levels of enteric bacteria including Bacteroides thetaiotamicron, Escherischia coli, Enterococcus faecalis, Bacteroides fragilis, Enterobacter cloacae complex, and Akkermansia muciniphila. The fungal composition of kombucha products was characterized by predominance of fermenting yeast including Brettanomyces species and Cyberlindnera jadinii. Kombucha varied widely in chemical content assessed by global untargeted metabolomics, with metabolomic variation being significantly associated with metagenomic profiles. Variation in tea bases, bacteria/yeast starter cultures, and duration of fermentation may all contribute to the observed large differences in the microbial and chemical profiles of final kombucha products.

The influence of selected yeast starters (Kluyveromyces lactis L39, Kazachstania humilis AG5, Nakazawaea molendinolei IG9, Candida diddensiae IG12, and Candida adriatica L30) on the fermentation and final characteristics of natural-style Gordal and Manzanilla green table olives was investigated. In both cultivars, the addition of yeast starters had no significant influence on the evolution of physicochemical parameters or the final main metabolites compared to noninoculated olives. In the Gordal cultivar, K. lactis L39 originated the greatest enrichment of volatile compounds, whereas K. lactis L39 and C. adriatica L30 gave the best volatile profiles in the Manzanilla cultivar. In both cultivars, the β-glucosidase-positive strains N. molendinolei IG9, C. diddensiae IG12, and C. adriatica L30 produced no significant decrease in the total phenolic content at the end of fermentation. Although the yeast starters had a significant effect on the volatile contents of the fermented products, they did not have a significant influence on the main sensory characteristics perceived by a sensory panel. A significant linear relationship (R2 = 0.815, p < 0.001) was found and validated between the perceived bitterness intensity and the content of total phenols in olive pulp, providing a simple and objective method for the evaluation of bitterness in table olives without the need for sensory analysis.

This contribution aims to review the presence and the potential double role—positive or beneficial and negative or harmful—of fungi in fermented sausages as well as their use as starter cultures. Traditionally, studies have been focused on lactic acid bacteria; however, over the years, interest in the study of fungi has increased. The important contribution of yeasts and filamentous fungi to the quality and safety of fermented sausages has emerged from reviewing the literature regarding these fermented products. In conclusion, this review contributes to the existing literature by considering the double role of filamentous fungi and yeasts, the global fermented sausage market size, the role and use of starters, and the starters mainly present in the worldwide market, as well as the main factors to take into account to optimize production. Finally, some suggestions for future broadening of the sector are discussed.

Ochratoxin A (OTA) is a mycotoxin mainly produced by Aspergillus section Circumdati and section Nigri across the coffee chain. OTA is nephrotoxic and is a threat to human health. This review summarizes current knowledge on how to reduce OTA concentration in coffee from farm to cup. After a brief introduction to the OTA occurrence in coffee, current good management practices are introduced. The core of this review focuses on biocontrol and microbial decontamination by lactic acid bacteria, yeasts and fungi, and their associated enzymes currently reported in the literature. Special attention is given to publications closest to in vivo applications of biocontrol agents and microbial OTA adsorption or degradation agents. Finally, this review provides an opinion on which future techniques to promote within the coffee supply chain.

Fungal keratitis is a rare yet severe infection of the cornea. Fungal species distribution depends on the climate and socioeconomic status and can show regional variation. This retrospective single-center study was conducted at a tertiary eye care center and the collaborating Institute of Medical Microbiology in Switzerland. On investigating all fungal-positive corneal scrapings and contact lens assessments of patients with keratitis from January 2012 to December 2023, 206 patients were identified, of which 113 (54.9%) were female. The median age was 38 (IQR 29.8, [18–93]), and 154 (74.8%) applied contact lenses. The most commonly found pathogen was Candida spp., followed by Fusarium spp. Molds were 1.8 times more common than yeasts. Linear regression showed no significant increase or decrease in the infection rate over time (p = 0.5). In addition, 10 patients (4.9%) were found to have coinfections with Acanthamoeba, 11 (5.3%) with HSV-1, none with HSV-2, and 4 (1.9%) with VZV. This study provides a long-term overview of fungal-positive corneal scrapings and contact lens specimens of patients with fungal keratitis. Based on our results, coinfections with Acanthamoeba, HSV, and VZV are frequent, especially in patients wearing contact lenses. Thus, wearing contact lenses may facilitate coinfection in fungal keratitis.