Search Results (435)

Background: Prosthetic candidiasis remains a significant clinical challenge, particularly due to the ability of Candida species to form resilient biofilms on dental prostheses, which limits the efficacy of conventional antifungal treatments. In this context, developing strategies to prevent or reduce biofilm formation is essential. Objectives This study investigates the antifungal and antibiofilm potential of a hydrogel formulation incorporating aminochalcone AM-35 as a candidate for the prevention and treatment of prosthetic candidiasis. Methods: To achieve this, experiments were conducted to determine the minimum inhibitory concentration (MIC) of aminochalcone AM-35 against Candida albicans and Candida tropicalis strains. AM-35 was incorporated into a hydrogel, which was subsequently tested on biofilms formed by these yeast species, both individually and in combination. The experimental disks were sterilized and incubated with C. albicans, C. tropicalis, and a mixture of both strains for 120 h to allow biofilm maturation. After contamination, the samples were divided into four experimental groups: Group 1: Hydrogel; Group 2: Hydrogel+AM-35; Group 3: Sodium hypochlorite (positive control); and Group 4: No treatment. The samples were then subjected to a sonication process to disaggregate the cells, which were then cultured on plates for colony-forming unit (CFU/mL) counts. The hydrogel’s toxicity was evaluated in vivo using the Galleria mellonella model. Results: The hydrogel formulation demonstrated significant antimicrobial activity, with an MIC of 7.8 μg/mL for C. albicans and 3.9 μg/mL for C. tropicalis. Treatment with the hydrogel at a concentration of 39 μg/mL resulted in a significant reduction in the formation and viability of mixed-species biofilms (p < 0.05). Additionally, the results indicated robust activity against C. albicans and C. tropicalis without presenting toxicity in the Galleria mellonella model. In conclusion, the hydrogel formulation exhibited effective antibiofilm activity, significantly reducing the microbial load. Conclusions: These findings open new possibilities for the development of alternative treatments for prosthetic candidiasis. The research suggests that the use of chalcone-based compounds may represent a promising approach in combating fungal infections in dentistry. Full article

This review explores the accumulated research and technological potential of Saccharomyces eubayanus, a cold-tolerant wild yeast first isolated in 1997 from the Andean-Patagonian forests of Argentina but formally described in 2011. S. eubayanus has garnered attention since it was identified as the missing parent of the lager-beer yeast S. pastorianus and because it demonstrated valuable fermentative skills and an unexpected large intraspecific genetic diversity. The article recapitulates the characterization of the fermentative capacity of the type strain, as well as its ability to produce distinctive aromatic profiles compared to conventional lager yeasts. We discuss how these features have driven the development of improved strains through experimental evolution and the generation of interspecific hybrids with S. cerevisiae exhibiting appropriate fermentation performance and a broad aromatic diversity. We also aim to address the applications of S. eubayanus in commercial brewing, especially in the craft beer industry, and highlight its potential to add value and/or regional identity to beer through novel flavor profiles. Finally, the review outlines the main challenges limiting large-scale implementation, emphasizing the importance of continued research into strain development and brewing strategies to fully harness the potential of this wild yeast species. Full article

Precision fermentation, a highly controlled process of microbial fermentation, is emerging as a transformative tool to produce cosmetic ingredients. This technology leverages engineered micro-organisms to produce high-value compounds with applications in skincare, hair care, and other cosmetic formulations. Unlike traditional methods of ingredient sourcing, which often rely on extraction from plants or animals, precision fermentation offers a sustainable and scalable alternative, minimizing environmental impact and enhancing the consistency of ingredient supply. This paper explores the potential of precision fermentation to revolutionize the cosmetic industry by enabling the production of complex molecules, such as peptides, proteins, and other bioactive compounds, which are essential for cosmetic efficacy. Using synthetic biology, micro-organisms such as yeast, bacteria, and fungi are programmed to biosynthesize specific cosmetic ingredients, which can include antioxidants, emulsifiers, and moisturizers. This technique not only ensures high purity and ingredients safety but also allows for the production of novel compounds that may be difficult or impossible to obtain through traditional methods. Furthermore, precision fermentation can be employed to address growing consumer demand for cruelty-free, vegan, and eco-friendly products, as it eliminates the need for animal-derived ingredients and reduces resource consumption associated with conventional farming and extraction processes. This review highlights key advancements in the field, discussing the challenges faced by industry, such as regulatory framework, and presents potential solutions for overcoming these obstacles. The paper concludes by examining the prospects of precision fermentation in cosmetics, forecasting how continued innovation in this area could further drive sustainability, ethical production practices, and the development of highly functional, scientifically advanced cosmetic products. Full article

Due to the increasing interest in probiotic components to improve quality of life, this study aimed to investigate the bioactive potential of a paraprobiotic derived from a selected strain of probiotic lactic acid bacteria (Lacticaseibacillus paracasei MIUG BL80) on Saccharomyces cerevisiae MIUG D129, used as a cellular model organism. The paraprobiotics (inactivated cells) were obtained through a combination of ultrasonic and conventional heat treatments. It was observed that adding more than 10 % of the paraprobiotic suspension to the cultivation medium of yeast had a positive influence on the metabolic activity of the starter culture (S. cerevisiae). The specific growth rate increased from 0.227 in the control sample to 0.507 in the sample with 15% paraprobiotic supplementation (S3), while the generation time decreased from 4.403 h to 1.972 h. This suggests that adding probiotics to the cultivation medium enhances the metabolic performance of S. cerevisiae cells. Additionally, an improvement in yeast cell viability during wet biomass storage (from 48 h to 14 days at 4 °C) was observed. Full article

With the global population steadily rising, the demand for sustainable protein sources has become increasingly urgent. Traditional animal- and plant-based proteins face challenges related to scalability, resource efficiency, and environmental impact. In this context, single-cell protein has emerged as a promising alternative. Derived from microorganisms such as algae, bacteria, fungi, and yeast, single-cell protein offers a high nutritional profile- including all essential amino acids and vitamins—while enabling rapid production, minimal land and water requirements, and no generation of greenhouse gas emissions. A particularly compelling advantage of single-cell protein is its ability to be produced from agro-industrial waste, converting low-cost residues into valuable nutritional resources and contributing to environmental sustainability. Among these waste streams, lignocellulosic biomass from agricultural and forestry residues stands out as a renewable, biodegradable, and abundant feedstock. This review explores the potential of lignocellulosic waste as a substrate for single-cell protein production, emphasizing both its environmental advantages and nutritional value. It highlights the single-cell protein role as a sustainable and scalable alternative to conventional protein sources. The review also identifies key scientific, economic, and regulatory challenges, and recognizes the importance of targeted investments, particularly in policy development, public awareness, and technological innovation, to enable the broader adoption and acceptance of single-cell protein -based products. Full article

Although beer fermentation has traditionally been carried out with Saccharomyces, the boom in craft brewing has led to the use of non-conventional yeast species for beer production. This group also includes non-Saccharomyces starters, which are commonly used in winemaking and which have different technological characteristics compared to standard representatives of the Saccharomyces genus. One of the important characteristics of the non-Saccharomyces group is the richer enzyme profile, which leads to the production of beverages with different taste and aroma profiles. The aim of this study was to investigate sweet and hopped wort fermentation with seven strains of active dry non-conventional yeasts of Lachancea spp., Metschnikowia spp., Torulaspora spp. and a mixed culture of Saccharomyces cerevisiae and Torulaspora delbrueckii. One ale and one lager active dry yeast strain were used as control strains. The extract consumption, ethanol production, degree of fermentation, pH drop, as well as the yeast secondary metabolites formed by the yeast (higher alcohols, esters and aldehydes) in sweet and hopped wort were investigated. The results indicated that all of the studied types of non-conventional yeasts have serious potential for use in beer production in order to obtain new beer styles. For the purposes of this study, statistical methods, principle component analysis (PCA) and correlation analysis were used, thus establishing the difference in the fermentation kinetics of the growth in the studied species in sweet and hopped wort. It was found that hopping had a significant influence on the fermentation kinetics of some of the species, which was probably due to the inhibitory effect of the iso-alpha-acids of hops. Directions for future research with the studied yeast species in beer production are presented. Full article

Pardosa pseudoannulata plays an important role in the biological control of insect pests. The inclusion of yeast in the culture medium is very important for the growth, development, and reproduction of Drosophila melanogaster, but there have been few studies on the influence of nutrients in the culture medium on spider development. In order to explore the effects of different yeast treatments on the growth and development of D. melanogaster and as a predator, P.  pseudoannulata, three treatments (no yeast, active yeast added, and inactivated yeast added) were adopted to modify the conventional D. melanogaster culture medium. The addition of yeast to the medium shortened the development time from larva to pupation in D. melanogaster. The emergence and larval developmental times of D. melanogaster reared with activated yeast were shorter than those of the group without yeast addition, which promoted D. melanogaster emergence and increased body weight. The addition of yeast to the medium increased the fat, protein, and glucose content in D. melanogaster. The addition of activated yeast shortened the developmental time of P.  pseudoannulata at the second instar stage but had no effect on other instars. Different yeast treat-ments in the medium had no effect on the body length or body weight of P.  pseudoannulata. Adding yeast to D. melanogaster culture medium can increase the total fat content in P.  pseudoannulata, but it has no effect on glucose and total protein in P.  pseudoannulata. Our study shows the importance of yeast to the growth and development of fruit flies. Full article

CRISPR technology, which is derived from the bacterial adaptive immune system, has transformed traditional genetic engineering techniques, made strain engineering significantly easier, and become a very versatile genome editing system that allows for precise, programmable modifications to a wide range of microbial genomes. The economies of fermentation-based manufacturing are changing because of its quick acceptance in both academic and industry labs. CRISPR processes have been used to modify industrially significant bacteria, including the lactic acid producers, Clostridium spp., Escherichia coli, and Corynebacterium glutamicum, in order to increase the yields of bioethanol, butanol, succinic acid, acetone, and polyhydroxyalkanoate precursors. CRISPR-mediated promoter engineering and single-step multiplex editing have improved inhibitor tolerance, raised ethanol titers, and allowed for the de novo synthesis of terpenoids, flavonoids, and recombinant vaccines in yeasts, especially Saccharomyces cerevisiae and emerging non-conventional species. While enzyme and biopharmaceutical manufacturing use CRISPR for quick strain optimization and glyco-engineering, food and beverage fermentations benefit from starter-culture customization for aroma, texture, and probiotic functionality. Off-target effects, cytotoxicity linked to Cas9, inefficient delivery in specific microorganisms, and regulatory ambiguities in commercial fermentation settings are some of the main challenges. This review provides an industry-specific summary of CRISPR–Cas9 applications in microbial fermentation and highlights technical developments, persisting challenges, and industrial advancements. Full article

Amid growing global concerns about environmental sustainability and food security, plant-based meat substitutes have emerged as a promising alternative to conventional meat. However, current formulations, especially those based on soy protein isolate (SPI) often fail to replicate the desired texture and structural integrity. To address this limitation, this study aimed to evaluate the use of whole yeast powder (WYP) combined with SPI for producing plant-based meat analogues via high-moisture extrusion. Seven groups were designed: a control group with 0% WYP, five treatment groups with 5%, 10%, 20%, 30%, and 40% WYP, and one reference group containing 20% yeast protein powder (YPP). Although lower in protein content than yeast protein powder (YPP), whole yeast powder exhibits superior water-binding capacity and network-forming ability owing to its complex matrix and fiber content. At a 20% inclusion level, whole yeast powder demonstrated a higher fibrous degree (1.84 ± 0.02 vs. 1.81 ± 0.04), greater hardness (574.93 ± 5.84 N vs. 531.18 ± 17.34 N), and increased disulfide bonding (95.33 ± 0.92 mg/mL vs. 78.41 ± 0.78 mg/mL) compared to 20% YPP. Scanning electron microscopy (SEM) and low-field nuclear magnetic resonance (LF-NMR) revealed that whole yeast powder facilitated the formation of aligned fibrous networks and enhanced water binding. Fourier transform infrared spectroscopy (FTIR) confirmed an increase in β-sheet content (0.267 ± 0.003 vs. 0.260 ± 0.003), which contributed to improved protein aggregation. Increasing the WYP content to 30–40% led to a decline in these parameters, including a reduced fibrous degree (1.69 ± 0.06 at 40% WYP) and weakened molecular interactions (p < 0.05). The findings highlight 20% WYP as the optimal substitution level, offering superior textural enhancement and fibrous structure formation compared to YPP. These results suggest that WYP is not only a cost-effective and processing-friendly alternative to YPP but also holds great promise for scalable industrial application in the plant-based meat sector. Its compatibility with extrusion processes and ability to improve sensory and structural attributes supports its relevance for sustainable meat analogue production. Full article

The singular biodiversity of the Brazilian Caatinga inspires innovative solutions in food science. In this study, we evaluated the prebiotic potential of honeys produced by Apis mellifera in the Pajeú hinterland, Pernambuco, Brazil (Caatinga Biome), with different floral origins: Mastic (Aroeira), Mesquite (Algaroba), and mixed flowers. These were used to formulate synbiotic and alcoholic beverages fermented by Saccharomyces boulardii CNCM I-745. Static and dynamic simulations of the human gastrointestinal tract (GIT) were used, as well as physicochemical, rheological, and microbiological analyses. The results revealed that honey positively influences the viability and resilience of probiotic yeast, especially honey with a predominance of Algaroba, which promoted the highest survival rate (>89%) even after 28 days of refrigeration and in dynamic in vitro simulation of the GIT (more realistic to human physio-anatomical conditions). The phenolic composition of the honeys showed a correlation with this tolerance. The use of complementary methodologies, such as flow cytometry, validated the findings and highlighted the functional value of these natural matrices, revealing an even greater longevity potential compared to conventional microbiological methodology. The data reinforces the potential of the Caatinga as a source of bioactive and sustainable compounds, proposing honey as a promising non-dairy synbiotic vehicle. This work contributes to the appreciation of the biome and the development of functional food products with a positive social, economic, and ecological impact. Full article

The increasing demand for sustainable poultry production has urged the exploration of alternative feed strategies supporting animal performance and environmental goals. The first section outlines the protein requirements in broiler nutrition (19–25% crude protein) and the physiological importance of balanced amino acid profiles. Vegetal conventional protein sources are discussed in terms of their nutritional value (12.7–20.1 MJ/kg), limitations (antinutritional factors), and availability. Emerging trends in broiler nutrition highlight the integration of supplements and the need for innovative feed solutions as support for the improvement in broiler body weight and feed efficiency increase. Microbial protein sources: yeast biomass (41–60% of 100 g dry weight), microbial mixed cultures (32–76% of 100 g dry weight), and beer by-products, such as brewer’s spent yeast (43–52% of 100 g dry weight), offer promising nutritional profiles, rich in bioactive compounds (vitamin B complex, minerals, enzymes, and antioxidants), and may contribute to improved gut health, immunity, and feed efficiency when used as dietary supplements. The review also addresses the regulatory and safety considerations associated with the use of microbial protein in animal feed, emphasizing EU legislation and standards. Finally, recent findings on the impact of microbial protein supplementation on broiler growth performance, carcass traits, and overall health status are discussed. This review supports the inclusion of microbial protein sources as valuable co-nutrients that complement conventional feed proteins, contributing to more resilient and sustainable broiler production and broiler meat products. Full article

Wine vinegar and wine are traditional Spanish products, obtained from grape must by alcoholic fermentation (wine) and subsequent acetification (vinegar). Although these are established products, there is great interest in the development of new products, particularly new vinegars, and among these, the possibility of vinegars containing gluconic acid stands out. Gluconic acid in vinegar, mainly produced by acetic acid bacteria (AAB), is positively valued by consumers. Its content depends on the availability of glucose in the base wine; however, this hexose is preferentially consumed by the indigenous yeast population which conducts the previous alcoholic fermentation. For this reason, the use of non-conventional fructophilic yeasts, which consume fructose rather than glucose, is required. In this work, we isolated, screened, and identified osmophilic and fructophilic non-Saccharomyces yeasts from sun-dried grape must and tested them under different fermentation conditions in synthetic and natural grape musts, in order to obtain a base wine with ethanol and glucose content for the development of new vinegars containing gluconic acid. The isolate of the species Starmerella lactis-condensi was found to be an ideal candidate due to its fructophilic and osmophilic features, which allowed for the production of a base wine with high ethanol (11% v/v) and glucose (up to 200 g/L) content from a natural concentrated must. In fresh must, inoculation with Starmerella lactis-condensi resulted in faster and preferential fructose consumption over glucose compared to the control. However, both sugars were completely consumed at the end of the alcoholic fermentation; therefore, new fermentation strategies should be tested in this type of must. Furthermore, this strain could be of interest in oenology due to its high glycerol yield and low volatile acid production during alcoholic fermentation. The use of this strain could allow for the production of new wines with unique metabolic profiles suitable for further vinegar production. Full article

Consumer demand for low-alcohol acidic beers is driving the use of non-conventional yeasts in the brewing process. In this study, the addition of mixed berries and fermentation with L. thermotolerans L31 are performed in crafting a low-alcohol acidic beer. Four different beers were brewed in the primary stage with either Saccharomyces cerevisiae or L. thermotolerans and with or without added berry mixture. Beer was fermented for 8 days at 20 °C, stored, and bottled. pH, density, alcoholic content, bitterness, and color of final beer were analyzed for all samples using analytical methods. Volatile compounds, anthocyanin content, and antioxidant activity were also evaluated. Sensory analysis was performed and correlated (PCA) with the analytical results. The obtained data indicated that beers brewed with L. thermotolerans were significantly more acidic and less bitter than S. cerevisiae beers. No difference in alcoholic content was found. Fruity aroma-associated compounds were present in L. thermotolerans beers, which correlated with the sensory analysis. Fruit beers were also redder and showed higher anthocyanin content and stronger antioxidant activity due to the presence of anthocyanins such as cyanidin, delphinidin, and malvidin from fruit, and other antioxidant compounds. Full article

The study of the effects of 2.45 GHz electromagnetic fields on the health and safety of people and organisms as a whole is essential due to their widespread use in everyday life. It is known that they can cause thermal and non-thermal effects—at the molecular, cellular and organismal level. Yeast suspensions were treated with 2.45 GHz microwave radiation in the near-field of antenna at two distances (2 and 4 cm) and two time periods (20 and 60 min)—setups resembling the use of mobile devices. The release of UV-absorbing substances from the cells was studied as an indicator of membrane permeabilization, total intracellular antioxidant activity and reduced glutathione were determined, and a comet assay for damage to the DNA was performed. A correlation between reduced antioxidants and increased membrane permeability during EMF treatment was observed at a distance of 2 cm for 20 min, suggesting the presence of oxidative stress, while a similar effect was not observed with conventional heating. Slightly increased membrane permeability was observed after irradiation for 60 min at a distance of 4 cm, but this was not related to the antioxidant status of the cells. A trend towards increased DNA damage was observed under both conditions. Full article

In view of the growing global need for sustainable protein sources, this study explores the utilization of short-chain fatty acids into single-cell protein using the non-conventional yeast Cyberlindnera jadinii. Short-chain fatty acids can be sustainably produced via anaerobic digestion of organic waste, presenting a promising fermentation substrate for a circular bioeconomy. Cyberlindnera jadinii is demonstrated to be capable of growing on acetate, propionate and butyrate as both a carbon and energy source without strong inhibition. Bioprocess development was conducted in stirred tank bioreactors, where a fed-batch pH-stat bioprocess led to improved efficiency without substrate inhibition. The highest titer of 31.3 ± 1.0 g/L, rate of 0.67 ± 0.02 g/L/h and yield of 0.36 ± 0.01 g/g was achieved with propionate. The resulting biomass contained 41.3% crude protein, and 17.3% crude lipids with 81% unsaturated fatty acids. In contrast to acetate and butyrate, propionate as a substrate led to accumulation of 37% odd-chain fatty acids with titer, rate and yield of 1.74 ± 0.06 g/L, 0.037 ± 0.001 g/L/h and 0.020 ± 0.001 g/g. These findings confirm that short-chain fatty acids are viable fermentation substrates not only for single-cell protein, but also unsaturated and odd-chain fatty acid production with Cyberlindnera jadinii. Full article