Search Results (73)

During the grain and cereal production process, whether during harvesting, processing, or storage, errors can occur, compromising product quality and potentially leading to contamination by fungi, which produce toxic substances known as mycotoxins. When fed to animals, these contaminated grains and cereals can cause several negative effects on animal health, impacting their production performance, including immunosuppression, hepatotoxicity, nephrotoxicity, and reproductive problems. To minimize the problems caused by mycotoxins, anti-mycotoxin additives, also known as adsorbents, are used. These are inert materials that bind to mycotoxins and are excreted in feces, preventing their action within the animal’s body. Therefore, the objective of this study was to evaluate the effectiveness of an anti-mycotoxin product based on bentonite, activated charcoal, milk thistle extract, and yeast cell wall in the diet of mycotoxin-contaminated lambs on animal health and performance. Thirty lambs were divided into three homogeneous groups: control (without mycotoxins or additives), mycotoxin (with mycotoxins), and anti-mycotoxin (mycotoxins and additive). The mycotoxins used for feed contamination were aflatoxin (AFLA) (200 ppb), fumonisin (FUMO) (15 ppm), zearalenone (ZEA) (500 ppb), and deoxynivalenol (DON) (1.5 ppm). The anti-mycotoxin additive was used at a dose of 1 kg/ton of concentrate. Parameters of zootechnical performance, hematological profile, serum biochemistry, and oxidative status were evaluated. The group that ingested the contaminated concentrate with mycotoxin had a lower average daily weight gain (ADG) when compared to the control and anti-mycotoxin groups. Ingestion of a mycotoxin-contaminated diet increased the activity of aspartate aminotransferase and gamma-glutamyltransferase, which are indicators of liver damage. However, when the anti-mycotoxin additive was used, the increase in these enzymes was modest and lower than in the mycotoxin group. Ingestion of a mycotoxin-containing concentrate increased levels of oxidative stress biomarkers such as reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), myeloperoxidase (MPO), and reduced glutathione (GST), demonstrating that the mycotoxin challenge was effective in causing oxidative stress. However, when the diet was contaminated with mycotoxins and supplemented with the anti-mycotoxin additive, the levels of ROS and TBARS were similar to those of the negative control group. We concluded that adding the anti-mycotoxin product to the lambs’ diets prevented or minimized the problems caused by mycotoxin consumption, allowing these lambs to have ADG, and feed efficiency similar to the control group. Full article

Yeast and its derivatives, including yeast extract and yeast cell wall, are well established as safe and environmentally sustainable feed additives that significantly improve animal production performance and health. Their incorporation into swine production serves as an innovative nutritional strategy aimed at improving growth performance, bolstering health status, and enhancing immune function in pigs. As a versatile microorganism, yeast generates a variety of bioactive compounds through fermentation, such as amino acids, vitamins, enzymes, and growth factors, which collectively contribute to improved growth and overall health in pigs. This review consolidates current research on the utilization of yeast and yeast derivatives in swine production, highlighting their biological functions and practical implications within the industry. Full article

Rhododendron hybridum Ker Gawl, a widely cultivated horticultural species in China, is highly valued for its ornamental and medicinal properties. However, with the expansion of its cultivation, leaf spot disease has become more prevalent, significantly affecting the ornamental value of R. hybridum Ker Gawl. In this study, R. hybridum Ker Gawl from the Kunming area was selected as the experimental material. The tissue isolation method was employed in this study to isolate pathogenic strains. The biological characteristics of the pathogens were determined using the mycelial growth rate method. The pathogens’ influence on the host plant’s ultrastructure was investigated using transmission electron microscopy (TEM). Colletotrichum nymphaeae was identified as the pathogen implicated in the development of leaf spot disease in R. hybridum Ker Gawl across three regions in Kunming City through the integration of morphological traits and phylogenetic analyses of multiple genes (ITS, ACT, GAPDH, HIS3, CHS1, and TUB2). Its mycelial growth is most effective at a temperature of 25 °C. pH and light have relatively minor effects on the growth of mycelium. The preferred carbon and nitrogen sources were identified as mannitol and yeast extract, respectively. Additionally, TEM observations revealed significant damage to the cell structure of R. hybridum Ker Gawl leaves infected by the pathogen. The cell walls were dissolved, the number of chloroplasts decreased markedly, starch granules within chloroplasts were largely absent, and the number of osmiophilic granules increased. This is the first report of leaf spot disease in R. hybridum Ker Gawl caused by C. nymphaeae. The results of this study provide valuable insights for future research on the prevention and control of this disease. Full article

This research focused on producing water-soluble carbohydrates extracts from the leaves of the wild plant Cacalia firma using commercial enzymatic processes. Different enzymes and conditions were applied to the leaves to determine the optimal method for extracting carbohydrates. Enzymes used were Cellic CTec3 HS, Celluclast 1.5 L, Viscozyme L, Pectinex ultraSP-L, and Amylase AG. Pectinase, cellulase, and other enzymes are isolated from yeast, bacteria, or some higher plants and are commonly used to break down pectin, which is the cell wall or intercellular connective tissue in plant tissues, to soften fruit or vegetable tissues and to make sugars. They are commonly used to soften the tissues of fruits and vegetables, to produce sugars, or to increase the yield of juice in fruit processing. The resulting water-soluble carbohydrates demonstrated significant antioxidant capabilities in vitro, as evidenced by DPPH radical-scavenging and ABTS assays. Furthermore, the carbohydrates exhibited high levels of total polyphenol and flavonoid content. The extraction methodology was fine-tuned using response surface methodology alongside the Box–Behnken design, achieving a maximum carbohydrate yield of 129.7 mg/g, which was very close to the predicted value of 132.4 mg/g. The optimal conditions included an extraction temperature of 47.3 °C, a duration of 63 h, and a pH of 3.7 using Viscozyme L. This study offers a theoretical foundation for the development of natural carbohydrate antioxidants and lays the groundwork for large-scale production and utilization of C. firma leaf carbohydrates. These extracts, showing antioxidant activity, hold potential as functional ingredients in the food industry. Full article

Yeast biomass, a by-product of various industrial processes, is a sustainable source of food ingredients. Despite its nutritional richness, studies on Yarrowia lipolytica W29 biomass for high-value compound production using low-cost substrates like glycerol and glucose remain limited. These substrates enhance productivity and modulate cell wall composition. Extracting these compounds is complex but can be optimized through sequential hydrolysis, including autolysis and acid hydrolysis. In this study, mannoprotein exhibited a 60% emulsification index, 40 mN m⁻¹ surface tension for both substrates, and thermal stability with a mass retention above 30%. Acid hydrolysis yielded bioactive peptides (<1 kDa) with the highest antioxidant activity: 220 µM Trolox (ABTS), 270 µM Trolox (DPPH), and 125 µM ascorbic acid (FRAP). The raw biomass and feed ingredient (dry residue) provided 100% and 90% of the daily protein intake, respectively, with a β-glucan content of 17%. Glycerol and glucose resulted in similar high-value compounds, highlighting glycerol as a cost-effective carbon source. Thus, sequential hydrolysis is an effective strategy for extracting compounds from Y. lipolytica W29 biomass, offering a promising alternative for industrial applications due to its high nutritional value and functional properties. Full article

Total mixed ration silage has been used as a strategy to optimize the use of dry and wet feed in ruminant feeding. Another promising technique is silage reallocation, which allows producers to divide the ensiled material in large silos into smaller units that can be easily transported and marketed. Thus, this study aimed to improve food preservation through the development of total mixed rations (TMRs) based on relocated sorghum silage (RSS) and cactus pear for sheep diets. A completely randomized design was used with five treatments (0, 15, 25, 30, and 35% RSS inclusion on a dry matter basis) and five replicates. Ninety days after ensiling, the silos were opened. The fermentation characteristics, nutritional aspects, aerobic stability, and microbial populations of TMR silages were evaluated. The inclusion of RSS showed a quadratic effect on pH, density, permeability, lactic acid bacteria and yeast counts, and total carbohydrates (p < 0.05). It reduced gas and effluent losses, porosity, ammonia nitrogen, buffer capacity, ash, crude protein, ether extract, and non-fibrous carbohydrates (p < 0.05) while increasing dry matter, neutral and acid detergent fiber, hemicellulose, and cellulose contents (p < 0.05). There was an interaction effect between the levels of RSS inclusion and exposure times to air on CO₂ and dry matter content (p < 0.05). Regarding carbohydrate fractionation, there was a reduction in fraction A + B1 (non-fibrous carbohydrates) and an increase in fractions B2 (fibrous carbohydrates from the cell wall and of slow ruminal availability, susceptible to the effects of the passage rate) and C (indigestible neutral detergent fiber) (p < 0.05). For protein fractionation, a quadratic effect was observed for fractions A (non-protein nitrogen) and C (insoluble protein, indigestible in the rumen and intestine), an increase in fraction B1 (soluble protein rapidly degraded in the rumen) + B2 (insoluble protein with intermediate degradation rate in the rumen), and a reduction in fraction B3 (insoluble protein with slow degradation rate in the rumen) (p < 0.05) as RSS levels increased. Under the experimental conditions, it is recommended to include up to 30% RSS in the total mixed ration silage to improve microbiological characteristics, reduce gas and effluent losses, and increase dry matter recovery and nutritional aspects of silage when associated with cactus pear. Full article

The structure of yeast cells, which are rich in bioactive compounds, makes them an attractive encapsulation vehicle due to their antioxidant, antibacterial, and antimutagenic properties. In this study, black chokeberry extract was encapsulated with different wall materials (maltodextrin, gum arabic, mixture of maltodextrin and gum arabic, plasmolyzed yeast, and non-plasmolyzed yeast) by freeze-drying. While the highest encapsulation efficiency was obtained with maltodextrin (98.82%), non-plasmolyzed yeast (86.58%) emerged as a viable alternative to gum arabic. The largest particle size was observed in plasmolyzed yeast microcapsules. Yeast-coated capsules exhibited a spheroidal morphology. Differential Scanning Calorimetry revealed high thermal stability for all microcapsules, with the gum arabic-coated microcapsules demonstrating the greatest stability. After the simulated gastric and intestinal fluid treatment, plasmolyzed yeast provided the highest retention, with 63.45% and 77.55% of phenolics, respectively. The highest 2,2-Diphenyl-1-picrylhydrazyl (DPPH) activities were found in yeast microcapsules, with no significant difference between them. In 2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS^•+) scavenging activity, the least loss (approximately 10%) was observed in non-plasmolyzed yeast samples after intestinal digestion. These results showed that yeast can be used as an alternative coating material in the encapsulation of phenolics, and it contributes to the bioavailability of microcapsules with its protective effect during digestion. Full article

Background/Objectives: DNA vaccines are rapidly produced and adaptable to different pathogens, but they face considerable challenges regarding stability and delivery to the cellular target. Thus, effective delivery methods are essential for the success of these vaccines. Here, we evaluated the efficacy of capsules derived from the cell wall of the yeast Pichia pastoris as a delivery system for DNA vaccines. Methods: The capsules were extracted from the yeast Pichia pastoris strain GS115, previously grown in a YPD medium. pVAX1 expression vector was adopted to evaluate the DNA vaccine insertion and delivery. Three encapsulation protocols were tested to identify the most effective in internalizing the plasmid. The presence of plasmids inside the capsules was confirmed by fluorescence microscopy, and the encapsulation efficiency was calculated by the difference between the initial concentration of DNA used for insertion and the concentration of unencapsulated DNA contained in the supernatant. The capsules were subjected to different temperatures to evaluate their thermostability and were co-cultured with macrophages for phagocytosis analysis. HEK-293T cells were adopted to assess the cytotoxicity levels by MTT assay. Results: The microscopy results indicated that the macrophages successfully phagocytosed the capsules. Among the protocols tested for encapsulation, the one with 2% polyethylenimine for internalization showed the highest efficiency, with an encapsulation rate above 80%. However, the vaccine capsules obtained with the protocol that used 5% NaCl showed better thermal stability and encapsulation efficiency above 63% without induction of cell viability loss in HEK 293T. Conclusions: We successfully described a vaccine delivery system using yeast capsules derived from Pichia pastoris, demonstrating its potential for DNA vaccine delivery for the first time. Additional studies will be needed to characterize and improve this delivery strategy. Full article

Components of yeast cell walls, such as β-glucans and mannoproteins, show promise for developing sustainable biopolymers for food packaging. Efficient extraction, however, is challenging due to the complexity of the yeast cell wall. This study explored high-pressure homogenisation (HPH) and pulsed electric fields (PEFs), alone and with heat treatment (TT), on bakery yeast (BY) and brewery spent yeast (BSY) biomasses. In the treated samples we assessed carbohydrates, proteins, β-glucans, and mannoproteins and evaluated cell wall disruption microscopically. HPH caused complete cell disintegration, enhancing intracellular release, while PEF primarily permeabilised the membranes. Combined HPH and PEF treatments significantly increased cell wall stress, leading to partial disintegration. Notably, the β-glucans released reached 3.90 g/100 g dry matter in BY and 10.44 g/100 g dry matter in BSY, demonstrating significant extraction improvements. These findings highlight the potential of HPH and PEF for enhancing β-glucan recovery from yeast biomass, offering a promising route for sustainable biopolymer production for food packaging. Full article

Yeasts have emerged as an important resource of bioactive compounds, proteins and peptides, polysaccharides and oligosaccharides, vitamin B, and polyphenols. Hundreds of thousands of tons of spent brewer’s yeast with great biological value are produced globally by breweries every year. Hence, streamlining the practical application processes of the bioactive compounds recovered could close a loop in an important bioeconomy value-chain. Cell lysis is a crucial step in the recovery of bioactive compounds such as (glyco)proteins, vitamins, and polysaccharides from yeasts. Besides the soluble intracellular content rich in bioactive molecules, which is released by cell lysis, the yeast cell walls β-glucan, chitin, and mannoproteins present properties that make them good candidates for various applications such as functional food ingredients, dietary supplements, or plant biostimulants. This literature study provides an overview of the lysis methods used to valorize spent brewer’s yeast. The content of yeast extracts and yeast cell walls resulting from cellular disruption of spent brewer’s yeast are discussed in correlation with the biological activities of these fractions and resulting applications. This review highlights the need for a deeper investigation of molecular mechanisms to unleash the potential of spent brewer’s yeast extracts and cell walls to become an important source for a variety of bioactive compounds. Full article

The enzyme-assisted approaches for plant phenolics extraction are more eco-friendly methods compared to acid or alkaline hydrolysis. Carbohydrase enzymes can release free phenolics from plant materials by cleaving the glycosidic bonds between phenolic compounds and cell wall polymers. In this study, the efficiency of carbohydrase-assisted treatment approaches was evaluated to extract bioactive phenolics from hawthorn (Crataegus orientalis) fruit residues. Enzymatic treatment of the fruits was operated by using a crude cellulolytic enzyme cocktail from Rhizomucor miehei NRRL 5282 and a pectinase preparate from Aspergillus niger. Both cellulase and combined cellulase–pectinase treatments improved the total phenolic content (TPC) and antioxidant activity of extracts. The TPC increased to 1899 ± 27 mg gallic acid equivalents/100 g dry matter during the combined enzyme treatment, showing a strong correlation with the average antioxidant capacity determined by ferric-reducing antioxidant power (1.7-fold increment) and 2,2-diphenyl-1-picrylhydrazyl (1.15-fold increment) reagents. The major phenolics in enzyme-treated extracts were vanillic and ferulic acids, the concentrations of which increased 115.6-fold and 93.9-fold, respectively, during carbohydrase treatment. The planktonic growth of Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Chromobacterium violaceum was slightly inhibited by the extracts with minimum inhibitory concentration values between 15.0 and 77.9 mg/mL, while the yeasts tested were quite resistant to the samples. B. subtilis and yeast biofilms were sensitive to the enzyme-treated extracts, which also showed quorum-sensing inhibitory effects against C. violaceum. The obtained bioactive hawthorn extracts hold potential as a natural source of antioxidants and antimicrobials. Full article

This review focuses on the physical disruption techniques in extracting intracellular compounds, a critical step that significantly impacts yield and purity. Traditional chemical extraction methods, though long-established, face challenges related to cost and environmental sustainability. In response to these limitations, this paper highlights the growing shift towards physical disruption methods—high-pressure homogenization, ultrasonication, milling, and pulsed electric fields—as promising alternatives. These methods are applicable across various cell types, including bacteria, yeast, and algae. Physical disruption techniques achieve relatively high yields without degrading the bioactivity of the compounds. These techniques, utilizing physical forces to break cell membranes, offer promising extraction efficiency, with reduced environmental impacts, making them attractive options for sustainable and effective intracellular compound extraction. High-pressure homogenization is particularly effective for large-scale extracting of bioactive compounds from cultivated microbial cells. Ultrasonication is well-suited for small to medium-scale applications, especially for extracting heat-sensitive compounds. Milling is advantageous for tough-walled cells, while pulsed electric field offers gentle, non-thermal, and highly selective extraction. This review compares the advantages and limitations of each method, emphasizing its potential for recovering various intracellular compounds. Additionally, it identifies key research challenges that need to be addressed to advance the field of physical extractions. Full article

Bottle conditioning of beer is an additional fermentation step where yeast and fermentable extract are added to the beer for carbonation. During this process, yeast must overcome environmental stresses to ensure sufficient fermentation in the bottle. Additionally, the yeast must be able to survive for a prolonged time, as a decline in viability will lead to alterations in the product. Here, we investigated the effects of bottle conditioning on beer using six different yeast strains from the brewing, wine making, and distilling industries over 120 days. The ale and lager strains resulted in a beer possessing typical characteristics of a pale ale-style beer, whereas sparkling wine and distilling yeast strains resulted in aromas that were uncharacteristic, which was expected. In addition, we observed that the various strains had different propensities to survive during bottle conditioning. Proteomic analysis was performed to ascertain protein abundance changes and reveal biological processes that potentially enabled specific yeast strains to survive longer during secondary fermentation. Our results showed that proteins associated with oxidoreductase activity and mitochondrial ribosomes were increased in the yeast strain with superior survival and were able to respond to cellular stress more effectively, whereas proteins associated with cell wall modulation were increased in the strain with poor survival characteristics. Overall, we demonstrated the impact of yeast selection on bottle conditioning and the biological processes involved in yeast physiology under these conditions. Full article

Taphrina deformans is the causal agent of leaf curl, a serious peach disease which causes significant losses in peach production worldwide. Nowadays, in order to control plant diseases, it is necessary to adopt novel and low-cost alternatives to conventional chemical fungicides. These promising strategies are targeted at eliciting host defense mechanisms via priming the host through the consecutive application of plant immunity inducers prior to pathogen challenge. In this study, we investigated whether chitosan or yeast cell wall extracts could provide enhanced tolerance against leaf curl in two-season field trials. Furthermore, we addressed the possible molecular mechanisms involved beyond the priming of immune responses by monitoring the induction of key defense-related genes. The efficacy of spraying treatments against peach leaf curl with both inducers was significantly higher compared to the untreated control, showing efficacy in reducing disease severity of up to 62.6% and 73.9% for chitosan and yeast cell wall extracts, respectively. The application of chitosan in combination with copper hydroxide was more efficient in reducing disease incidence and severity, showing efficacy values in the range of 79.5–93.18%. Peach plantlets were also spray-treated with immunity inducers three times prior to leaf inoculation with T. deformans blastospores in their yeast phase. The relative expression levels of nine key defense and priming genes, including those encoding members of pathogenesis-related (PR) proteins and hub genes associated with hormone biosynthesis, were monitored by RT-qPCR across three days after inoculation (dai). The results indicate that pre-treatments with these plant immunity inducers activated the induction of genes involved in salicylic acid (SA) and jasmonate (JA) defense signaling pathways that may offer systemic resistance, coupled with the upregulation of genes conferring direct antimicrobial effects. Our experiments suggest that these two plant immunity inducers could constitute useful components towards the effective control of T. deformans in peach crops. Full article

A novel aerotolerant anaerobic bacterium (strain M4Ah^T) was isolated from a terrestrial mud volcano (Taman Peninsula, Russia). Cells were small, cell-wall-less, non-motile cocci, 0.32–0.65 μm in diameter. The isolate was a mesophilic, neutrophilic chemoorganoheterotroph, growing on carbohydrates (D-glucose, D-trehalose, D-ribose, D-mannose, D-xylose, D-maltose, D-lactose, D-cellobiose, D-galactose, D-fructose, and D-sucrose), proteinaceous compounds (yeast extract, tryptone), and pyruvate. Strain M4Ah^T tolerated 2% oxygen in the gas phase, was catalase-positive, and showed sustainable growth under microaerobic conditions. The dominant cellular fatty acids of strain M4Ah^T were C_16:0 and C_18:0. The G+C content of the genomic DNA was 32.42%. The closest phylogenetic relative of strain M4Ah^T was Mariniplasma anaerobium from the family Acholeplasmataceae (order Acholeplasmatales, class Mollicutes). Based on the polyphasic characterization of the isolate, strain M4Ah^T is considered to represent a novel species of a new genus, for which the name Peloplasma aerotolerans gen. nov., sp. nov. is proposed. The type strain of Peloplasma aerotolerans is M4Ah^T (=DSM 112561^T = VKM B-3485^T = UQM 41475^T). This is the first representative of the order Acholeplasmatales, isolated from a mud volcano. Full article