Fermentation Performance Research Articles

A high-resolution two-step evolution experiment in yeast reveals a shift from pleiotropic to modular adaptation.

Evolution by natural selection is expected to be a slow and gradual process. In particular, the mutations that drive evolution are predicted to be small and modular, incrementally improving a small number of traits. However, adaptive mutations identified early in microbial evolution experiments, cancer, and other systems often provide substantial fitness gains and pleiotropically improve multiple traits at once. We asked whether such pleiotropically adaptive mutations are common throughout adaptation or are instead a rare feature of early steps in evolution that tend to target key signaling pathways. To do so, we conducted barcoded second-step evolution experiments initiated from 5 first-step mutations identified from a prior yeast evolution experiment. We then isolated hundreds of second-step mutations from these evolution experiments, measured their fitness and performance in several growth phases, and conducted whole genome sequencing of the second-step clones. Here, we found that while the vast majority of mutants isolated from the first-step of evolution in this condition show patterns of pleiotropic adaptation-improving both performance in fermentation and respiration growth phases-second-step mutations show a shift towards modular adaptation, mostly improving respiration performance and only rarely improving fermentation performance. We also identified a shift in the molecular basis of adaptation from genes in cellular signaling pathways towards genes involved in respiration and mitochondrial function. Our results suggest that the genes in cellular signaling pathways may be more likely to provide large, adaptively pleiotropic benefits to the organism due to their ability to coherently affect many phenotypes at once. As such, these genes may serve as the source of pleiotropic adaptation in the early stages of evolution, and once these become exhausted, organisms then adapt more gradually, acquiring smaller, more modular mutations.

The physiological role of gamma-aminobutyric acid in relieving the effect of furfural inhibitor for improvement the production of lipid in D. intermedius Z8.

In order to improve the production and quality of lipid of D. intermedius Z8 under the furfural stress environment, different exogenous γ-aminobutyric acid (GABA) addition strategies and their reasons for improving the fermentation performance were investigated. For this purpose, the effect of different concentrations of furfural on the production of biomass and lipid in D. intermedius Z8 was researched. The result shows that the growth of D. intermedius Z8 nearly stopped when 1.0g/L furfural was adopted. However, when 1.5mmol/L GABA was used, the highest biomass and lipid production of 4.56g/L and 1.83g/L were obtained, respectively, which were 36.53% and 61.95% higher compared to the control group (the normal development BG11 medium). Additionally, the changes in microalgal cell morphology were analyzed using the scanning electron microscope (SEM) technology, and the results suggest that GABA addition could significantly mitigate the toxic effects of excessive furfural by maintaining the integrity of the cell. Simultaneously, the activities of key enzymes involved in fatty acid synthesis, such as nitrate reductase (NR), phosphatidic acid phosphatase (PAP), acetyl CoA carboxylase (ACC), and fatty acid synthase (FAS), were enhanced under the optimal condition, and thus improving lipid production. According to the results in this study, the exogenous GABA addition strategy is a simple and effective approach to improve microbial tolerance and enhance its fermentation performance.

Serial Re-Pitching of Yeast Impacts Final Flavor Profiles of Commercial Beer

The aroma-active compounds produced by Saccharomyces cerevisiae during the fermentation of wort are key to the unique aroma and flavour profiles of beer. In commercial fermentations, there is batch-to-batch variation depending on yeast “brewing fitness” or the health of the yeast, but how does yeast health impact fermentation performance and metabolite production during fermentation? To address this, daily samples were collected from three full-scale commercial fermentations. The specific gravity was measured immediately, and samples were collected for carbohydrate analysis by High-Performance Liquid Chromatography and volatile compound analysis by Head-Space Gas Chromatography Mass Spectrometry (HS-GC-MS). Acetate esters (3), medium-chain fatty acid ethyl esters (7), hop-derived compounds (3), and an off-flavour (1) were detected and identified, and their relative signal was recorded for each sample. While there did not appear to be an effect of generational age on the duration of fermentation, age, in terms of the number of generations from serial re-pitching, impacted the ratios of volatile compounds. This difference in ratios was observed as early as Day 2, resulting in a difference in the volatile compound profiles of finished beers, therefore resulting in inconsistency in the product. This is important knowledge for brewers as generational age must be considered when fermenting high-quality, consistent products and monitoring fermentation progress/duration may not be enough to determine the ability of yeast to produce balanced flavour profiles.

The effects of garlic as a feed additive on ruminal fermentability and ruminant performance: A meta-analysis

Garlic exhibits antimicrobial activity and it may serve as a feed additive for ruminants, yet quantitative summaries of its effects are lacking. Therefore, the current study evaluated the addition of various garlic products as feed additives on ruminal fermentability and ruminant performance using a meta-analysis method. The database was compiled from 37 articles with 157 comparison studies in Scopus and PubMed. The data sets were analysed using a random-effects model in OpenMEE software and the bias publication was evaluated by using Jeffreys's Amazing Statistics Program (JASP) software. The results revealed that garlic significantly increased the percentage of propionate, butyrate, valerate and iso-butyrate, as well as the total number of rumen bacteria, dry matter intake, crude protein intake and ruminant average daily gain (p < 0.05). In contradiction, garlic addition in ruminant feeds led to decreases in methane production, percentage of acetate, the ratio of acetate to propionate, in vitro neutral detergent fibre digestibility and the total number of protozoa (p < 0.05). The subgroup analysis indicated that garlic oil, garlic powder and garlic bulb decreased methane emissions, while garlic powder and garlic bulb raised the percentage of propionate. In conclusion, garlic products altered the percentage of total volatile fatty acids and total number of rumen microflora, while increasing the feed intake and body weight gain. Thus, garlic products could be used as a dietary additive to support sustainable ruminant animal production.

A comprehensive study on fermentation and aroma contributions of Torulaspora delbrueckii in diverse wine varieties: Insights from pure and co-fermentation studies

As a well-commercialized and utilized non-Saccharomyces yeast, Torulaspora delbruineckii is gaining increasing relevance in the winemaking industry. However, its ability to produce distinctive aromas in wine has been inconsistently reported in the literature. This study aimed to evaluate the fermentation performance and aroma properties of T. delbrueckii isolates through pure and co-fermentation with Saccharomyces cerevisiae across eight different wine varieties: Merlot, Zidaifu, Petit Verdot, Marselan, Italian Riesling, Sauvignon Blanc, Ugni Blanc, and Petit Manseng. A comprehensive analysis using HS-SPME-GC–MS, OPLS-DA, and Spearman’s correlation analysis was conducted. Key findings include: (1) The strain T. delbrueckii R12 exhibited higher extracellular enzyme activity compared to S. cerevisiae CECA and demonstrated superior sugar tolerance compared to six other native T. delbrueckii strains. (2) T. delbrueckii R12 exhibited strong fermentative capability, completing fermentation in 23 days across the eight wines, producing lower levels of acetic acid (0 ∼ 0.8 g/L reduction) and ethanol (0.1 ∼ 4.0 % v/v reduction), and higher levels of glycerol (0.1 ∼ 0.9 g/L increase) in the majority of wines. (3) Co-fermentation with T. delbrueckii and S. cerevisiae altered glycosidase activity, enhancing the varietal aroma intensity and complexity of the eight wines by releasing C6 compounds, terpenes and esters, and reducing higher alcohols and fatty acids. (4) The aroma contribution of T. delbrueckii R12 was variety-dependent, with isobutyl alcohol, isopentyl alcohol, 1-pentanol, and 1-propanol prevalent in red wines, and (Z)-2-hexen-1-ol more associated with white wines. Additionally, T. delbrueckii R12 consistently enhanced aromas in all eight experimental wines by increasing levels of 1-hexanol, farnesyl alcohol, linalool, citronellol, ethyl acetate, isobutyric acid and decanoic acid, while decreasing 1-pentanol, octanoic acid, isoamyl acetate, and ethyl laurate. Seven of the increased compounds were identified as signature aromas of T. delbrueckii R12, potentially contributing grass, floral, muscat, rose, fruit, caramel and buttery notes to the wines. This study confirms the significant role of T. delbrueckii in winemaking and wine aroma, resolving previous discrepancies in the literature. It provides new knowledge for innovating and diversifying wine production across various grape varieties.

Ethanol Production From Sugarcane Molasses: Effects of Ph, Supplementation, and Refrigeration in Simulated Industrial Conditions at a Microdistillary

Objective: This study aims to evaluate the effects of pH, ammonium sulfate supplementation, and refrigeration on fermentation performance in sugarcane molasses, with the goal of optimizing ethanol production under simulated industrial conditions. Theoretical Framework: The research builds on key concepts in biofuel production, emphasizing the role of pH, nutrient supplementation, and temperature control in influencing yeast metabolism and fermentation efficiency. Theories on enzymatic activity and nutrient absorption (Vidal et al., 2013; Gutierrez, 1993) provide the foundation for understanding the interactions between these factors. Method: A full 2³ factorial design was employed, evaluating the effects of pH (3.5 and 5.0), supplementation (0.0 and 1.0 g/L), and refrigeration (with or without) on fermentation efficiency, process efficiency, ethanol productivity, and substrate-to-cell conversion in a microdistillery. Analytical methods included spectrophotometry, refractometry, and chromatography. Results and Discussion: The results indicate that fermentation conditions with pH 3.5, without supplementation, and with refrigeration yielded the best performance, with significant increases in ethanol productivity and fermentation efficiency. The interaction between variables suggests that these factors should be considered jointly to optimize the process. Research Implications: The findings offer practical insights for improving fermentation in industrial biofuel production, particularly in optimizing conditions for ethanol yield and process efficiency under near-industrial conditions. Originality/Value: This study contributes by using a microdistillery to simulate industrial conditions, providing more accurate data for scaling ethanol production. It adds value by highlighting how specific combinations of pH, supplementation, and refrigeration can improve biofuel sustainability.

Acidogenic Fermentation of Organic Residual Solids: Effect of Different Alkaline Sources on pH, Alkalinity, and Fermentation Performance

Acidogenic Fermentation of Organic Residual Solids: Effect of Different Alkaline Sources on pH, Alkalinity, and Fermentation Performance

Assessing Process Conditions on Xylose Fermentation in Spathaspora passalidarum: Effects of pH, Substrate-to-Inoculum Ratio, Temperature, and Initial Ethanol Concentration.

Bioethanol represents a clean and renewable alternative to fossil fuels, offering a significant reduction in environmental impact. Second-generation ethanol (2G) is produced using lignocellulosic biomass, which presents additional challenges due to the presence of hemicellulose. The pentose sugars within hemicellulose cannot be efficiently metabolized by conventional yeast strains like Saccharomyces cerevisiae. Consequently, the yeast Spathaspora passalidarum has emerged as a promising candidate for mixed fermentation processes, given its ability to utilize xylose. This study presents an in-depth metabolic, stoichiometric, and kinetic analysis of the fermentation performance of Sp. passalidarum NRRL Y-27907 in mixed glucose and xylose cultures. Emphasis was placed on examining variables from a novel perspective compared to existing literature. Specifically, the impacts of initial inoculum-substrate ratios, substrate composition, pH, temperature, and ethanol sensitivity were analyzed using a mathematical bioprocess approach. Sp. passalidarum NRRL Y-27907 exhibited sequential sugar consumption, with xylose being utilized only after glucose was exhausted. Ethanol yields in mixed cultures were comparable to those in individual-sugar cultures. The best fermentative performance was observed at 30°C, with 25g/L of xylose and an inoculum of 0.50g/L. The strain exhibited significant robustness at pH 4.0 and was notably affected by initial ethanol concentrations up to 20g/L. These findings provide crucial insights into the metabolic and fermentative behavior of Sp. passalidarum NRRL Y-27907, offering valuable information for the design of consolidated bioprocesses from lignocellulosic materials.

Development of a flavor-oriented synthetic microbial community for pour-over rice wine: A comprehensive microbial community analysis

Huangjiu, a traditional Chinese alcoholic beverage, varies widely in quality and consistency when brewed using the traditional pour-over rice wine technique, largely due to the variability in its microbial community in an open fermentation environment. This study streamlined the microbial complexity using amplicon sequencing and culture-dependent methods, leading to the identification of a set of core microbial species instrumental in flavor development. A synthetic microbial community was crafted from these key species and employed in fermentation experiments. In this study, we demonstrated that the synthetic microbial community not only replicated the major flavor profiles of traditional pour-over rice wine but also it is further proved that the core species directly determines the main flavor of pour-over rice wine, these findings are supported by our quantitative analysis of volatile compounds and sensory evaluation data. This research underscores the potential of synthetic microbial communities in standardizing production processes and improving the sensory quality of traditional beverages like Huangjiu.

Alternative feedstocks for sustainable aviation fuels: Assessment of sugarcane-derived microbial oil

Pioneer facilities for Sustainable Aviation Fuels (SAF) convert fats, oils, and grease into hydrocarbons using the Hydroprocessed Esters and Fatty Acids (HEFA) technology. However, limited feedstock availability and sustainability concerns may restrict broader adoption. Biotechnology offers an alternative by enabling microbial oil production from sugars, expanding the feedstock portfolio with more productive biomass sources or waste materials. This study assessed the economic and environmental impacts of SAF production through HEFA using microbial oil from sugarcane, combining achievable fermentation performance with mature catalytic conversion. The results demonstrated SAF costs between $1.83 and $3.00 per liter and over 50 % reduction in greenhouse gas emissions compared to fossil fuels. Sensitivity analysis identified fermentation performance as the key factor driving these outcomes. Additionally, this approach yielded higher SAF per hectare than soybean-oil-based HEFA, potentially reducing emissions from land-use change.

Regulation of the RCK1 gene on the oxidative tolerance of Saccharomyces cerevisiae

Our previous work indicated that the quorum sensing (QS) effect could regulate the oxidative tolerance of Saccharomyces cerevisiae, and QS may impact oxidative and antioxidative metabolisms of S. cerevisiae by regulating the RCK1 gene. Therefore, this work proposed a reasonable logic that RCK1 could play roles in regulating the oxidative and antioxidative metabolisms of yeast cells. The results presented here suggested that the overexpression of RCK1 has a regulatory effect on the reduction of ROS level and the promotion of oxidative tolerance of S. cerevisiae. The overexpression of RCK1 promoted the ROS generation through activating the MAPK pathway; on the other hand, RCK1-regulated antioxidative metabolism played a more significant role to realize lower ROS level and higher oxidative tolerance of S288c-RCK1 and ΔARO80-RCK1 strains. To improve the fermentation performance of yeast while circumventing metabolic burden, a recombinant strain with over time-controlled overexpression of the RCK1 gene (i.e., S288c'-RCK1 strain) derived from S288c strain was successfully constructed to achieve artificial regulation of yeast oxidative tolerance. Transcriptomics analysis was further performed on both S. cerevisiae wild-type and S288c'-RCK1 strains to identify differentially expressed genes and analyze their functional pathway classification. This work is instructive for artificially modulating the oxidative tolerance of strains to enhance the fermentation performance of yeast.

The production of D-lactic acid by fermentation from the waste newspapers recycling as the carbon source

D-lactic acid (D-LA) is an important substance, which has been used in various end-use industries, including pharmaceuticals, food and milk beverages. Lignocellulose is a desirable material for D-LA fermentation, due to its hydrolysate rich in monosaccharides can be obtained from the wastes to finally achieve high D-lactate yields. In this study, the waste newspapers removed most of the lignin was applied as a carbon source to produce D-LA using Escherichia coli JH15, rice straw hydrolysate and mixed sugars (glucose and xylose) were selected as a control. Compared with rice straw hydrolysate, the waste newspapers hydrolysate as a carbon source for D-LA production has obvious advantages, including high D-LA concentration, fast fermentation speed and no need for detoxified treatment. Compared to the mixed sugars, the D-LA productivity and conversion yield of total sugars to D-LA did not been different significantly using waste newspapers hydrolysate as a fermentation substrate, but the fermentation duration was extended by 6 hours. The fermentation could be finished just after 16 hours in a 7-L fermenter, and the maximum concentration of D-LA reached 33.60 g/L, with a high conversion yield of total sugars to D-LA (0.92 g/g). According to the fermentation performances of the concentration of D-LA, the yield of D-LA, the conversion yield of total sugars to D-LA, the fermentation duration, the waste newspapers hydrolysate as a carbon source for D-LA production is an efficient strategy to enhance the economic feasibility of this bioprocess.

Effect of microwave-puffed on Auricularia auricula polysaccharide and probiotic fermentation on its biotransformation and quality characteristics during storage period

In this study, probiotics with superior fermentation performance were screened, and the mixed-bacteria fermentation was carried out with Auricularia auricula treated with microwave-puffed process as fermentation substrate, and the changes in nutritional quality under different storage conditions were investigated. The results showed that the acid and bile salt resistance of Lactiplantibacillus plantarum 21,801 and 21,805 reached 95 % and 75 % respectively, and the intestinal adhesion was superior; microwave puffing treatment had the highest retention rate of A. auricula polysaccharides and the lowest loss of polyphenols, and no effect on soluble protein. Mixed bacterial fermentation significantly increased the total polyphenols and total flavonoids of A. auricula (p < 0.05), and the DPPH and ABTS radical scavenging reached 48.31 % and 73.21 % respectively. Furthermore, the viable counts, DPPH radical scavenging, color, and sensory quality of fermented A. auricula remained stable when stored at 4 °C. In contrast, when stored at 25 °C for 7 days, the taste was unfavorable, undesirable odor and spoilage occurred; by 21 days, DPPH clearance rate dropped below 40 % and color changed significantly (△E > 2). In conclusion, the probiotic mixed fermentation and storage conditions had a significant effect on the biometabolic transformation of macromolecules and other substances in A. auricula.

Impact of Natural Phytosanitary Product Residuals on Yeast Fermentation Performance and Wine Composition.

Although phytosanitary treatments are necessary to protect grapes from parasitic diseases, consumers are increasingly concerned about the use of synthetic phytosanitary products and their possible residues in wine. Pre-harvest phytosanitary treatments are often inevitable, and consequently downtime is required to avoid possible residues on the grapes. Instead, natural phytosanitary products, such as essential oil (EO)-based products, can be applied close to the harvest without specific restrictions, with results that are not only technically convenient but also more attractive for the consumers. Because of the high antimicrobial activity of EO products, in the present study we evaluated the effect of different residual amounts of two new EO-based phytosanitary products on the alcoholic fermentation and the chemical composition of the final fermented products. In particular, two EO-based new formulations, exploitable in organic viticulture management, were evaluated. Increasing concentrations of each formulation were tested during laboratory scale fermentations and in comparison with synthetic and natural commercial phytosanitary products. Growth and fermentation kinetics of a commercial yeast strain of Saccharomyces cerevisiae and the chemical and sensory profiles of the final products were evaluated. Both new formulations showed no significant impact on the growth and fermentation kinetic of S. cerevisiae at any of the concentrations tested. In all trials, alcoholic fermentation was completed in 15 days. Instead, a different chemical composition of the final products was observed. Therefore, these new products might represent an interesting alternative tool to the conventional phytosanitary treatments, being applicable close to the harvest without negative impacts on the kinetics of alcoholic fermentation and also being more acceptable to wine consumers.

Fermentation Performance of Carob Flour, Proso Millet Flour and Bran for Gluten-Free Flat-Bread.

Sourdough fermentation is rarely used for gluten-free flatbread (GFFB), a product that is challenging to produce, especially when using high-fiber ingredients that bring nutritional benefits but lead to physical deterioration. The aim of this study was therefore to evaluate the fermentation performance of carob flour (CSPF), proso millet flour (PMF), and proso millet bran (PMB) individually and in combination with Limosilactobacillus fermentum and Kluyveromyces marxianus (LF + KM) and to compare the performance of LF + KM with a commercial starter (LIVENDO® LV1). A mixture design (n = 13) was used to evaluate the fermentation performance of LF + KM (total titratable acidity (TTA); lactobacilli and yeast growth; acetic and lactic acid, fructose, glucose, and saccharose content) at 35 °C for 16 h. The comparison of LF + KM with LV1 fermentation was based on the acidity rate, fermentation quotient, TTA, and finally by determining the physical properties (texture, shape, color) of a rice-corn GFFB in which 10% of flour was supplemented with the sourdoughs. PMB promoted the growth of lactobacilli and the production of organic acids, especially in combination of CSPF and PMF. The optimum flour ratio was 2.4:1:1.2 (PMB:PMF:CSPF). LF + KM shortened the sourdough fermentation time by 2.5 times compared to LV1. The use of LF + KM sourdough reduced the hardness (32%) and chewiness (28%) of the GFFB, while the volume (35%) was increased compared to LV1 sourdough. This study shows the potential of using local alternative flours in sourdough fermentation for the production of GFFB.

Growth performance and ruminal fermentation characteristics of Thai-native beef cattle fed cassava pulp fermented with Lactobacillus casei TH14 and additives.

Raw cassava pulp is a low-nutritional agro-industry residue with a high moist content that is susceptible to rot. Biodegradation of cassava pulp by adding Lactobacillus spp. plus stimulants could boost bio-acidity to preserve cassava pulp as ruminant feed. This investigation assessed the effect of ensiled cassava pulp without or with Lactobacillus casei TH14 (LTH14), urea, and molasses on the intake, digestibility, rumen fermentation, and growth performance of native Thai beef cattle. Eight Thai-native beef bulls (170.3 ± 20.2kg of initial body weight) were randomly assigned to two treatment groups in a completely randomized design: cassava pulp ensiled without additives (CPFNO; n = 4) and cassava pulp ensiled with the combination of LTH14 (2.5g per ton of fresh material), urea (4% DM), and molasses (4% DM) (CPFWA; n = 4). The intake of the concentrate diet and ensiled cassava pulp did not differ (p > 0.05) between the CPFNO and CPFWA groups, including final body weight, average daily gain (ADG), and feed conversion ratio (p > 0.05). However, CPFWA affected higher rice straw intake compared to the CPFNO group (p < 0.05). The intake and digestibility of crude protein (CP) were greater for the CPFWA group at 43.86% and 30.87%, respectively, compared to the CPFNO group (p < 0.05). Ruminal ammonia-nitrogen (NH3-N)and blood urea-nitrogen (BUN) were increased when animals were fed with CPFWA (p < 0.05). The average total volatile fatty acids (VFA) concentration of CPFWA was greater than that of CPFNO by 27.49% (p < 0.05). In conclusion, CPFWA supplementation can enhance rice straw intake, CP intake and digestion, total ruminal VFA concentration, and BUN levels, without adversely affecting growth performance.

Effect of the quorum sensing signal molecule auto-inducer-2 on fermentation performance of Lactobacillus delbrueckii subsp. Bulgaricus DPUL-F36

Fermented milk is a typically product of co-fermentation by a variety of lactic acid bacteria (LAB). Quorum sensing (QS), as an intercellular communication mechanism of bacteria, may serve as a key factor influencing the quality of fermented milk. In this study, the fermentation performance of Lactobacillus delbrueckii subsp. bulgaricus DPUL-F36 were evaluated after supplementation with auto-inducer-2 (AI-2). The protein-protein interaction network (PPIN) was used to retrieve the interactions between QS genes and four major metabolic pathway genes. The expression of luxS gene in DPUL-F36 may affect amino acid metabolism, carbohydrate metabolism and cell wall formation. The key differential metabolites were identified by metabolomics analysis. A variety of amino acids including L-Glutamic, L-Tryptophan, L-Threonine, L-Histidine and L-Glutamine were found to be up-regulated in response to the addition of AI-2. Malic acid and succinate gradually accumulate in the tricarboxylic acid cycle. The consumption of citric acid increased with the fermentation process. In terms of rheological and texture characteristics of fermented milk, addition of AI-2 could effectively improve its shear stress resistance, firmness and index of viscosity. Our research provided a theoretical basis for improving the fermentation performance of DPUL-F36 strains, and support for the screening of excellent composite starter culture.

Effects of spent substrate of oyster mushroom (Pleurotus ostreatus) on ruminal fermentation, microbial community and growth performance in Hu sheep.

The study aimed to evaluate the effects of Pleurotus Spent Mushroom Substrate (P.SMS) on the rumen microbiota, encompassing bacteria and fungi, as well as their interactions in Hu sheep. A total of forty-five 3-month-old Hu sheep were randomly assigned to five groups. Each group was fed diets in which whole-plant corn silage (WPCS) was substituted with P.SMS at varying levels: 0% (CON), 5% (PSMS5), 10% (PSMS10), 15% (PSMS15), or 20% (PSMS20). The results indicated that higher proportions of P.SMS during the experimental period might have a detrimental effect on feed utilization efficiency, kidney function, and blood oxygen-carrying capacity. Notably, moderate levels of P.SMS, specifically below 15%, were associated with improvements in rumen NH3-N levels and absorption capacity. The results indicated that (1) PSMS20 exhibited a significantly higher feed-to-gain ratio compared to CON (P < 0.05); (2) PSMS15 showed a significantly higher NH3-N content than CON, PSMS5, and PSMS20. Additionally, PSMS10 and PSMS20 had elevated concentrations of NH3-N compared to CON and PSMS5 (P < 0.05); (3) The length and width of rumen papillae were significantly greater in PSMS20 compared to CON and PSMS5 (P < 0.05); (4) Creatinine levels were significantly higher in PSMS20 than in CON, PSMS5, and PSMS10 (P < 0.05); (5) By the conclusion of the experiment, hemoglobin concentration in PSMS20 showed a significant increase compared to CON (P < 0.05). Furthermore, the addition of P.SMS influenced microorganisms at both the phylum and genus levels: (1) At the phylum level, the prevalence of Patescibacteria was significantly lower in PSMS20 compared to the other groups; (2) PSMS15 exhibited significantly higher relative abundances of Basidiomycota compared to CON and PSMS10, while PSMS20 also demonstrated significantly higher relative abundances compared to CON (P < 0.05); (3) At the genus level, the prevalence of Candidatus_Saccharimonas in PSMS20 was significantly lower than in PSMS5, PSMS10, and PSMS15. Conversely, the prevalence of Phanerochaete in PSMS15 was notably higher than in CON and PSMS10, and it was also significantly elevated in PSMS20 compared to CON (P < 0.05); (4) Correlation analysis indicated no significant correlation between changes in the structure of bacterial and fungal communities. Considering these findings, a high percentage of P.SMS negatively impacted feed utilization efficiency, blood oxygen carrying capacity, and kidney function, while a moderate percentage of P.SMS promotes rumen absorption capacity, indicating that feeding 10% P.SMS is optimal.

Isolation and identification of epiphytic Pichia kudriavzevii from loquat peels and investigation of its fermentation characteristics for liquor production.

During the process of fruit wine production, yeast plays a crucial role in influencing the taste, flavor, and overall quality of the wine. This study aims to enhance the flavor and quality of loquat wine by isolating strains of Pichia kudriavzevii (P. kudriavzevii) with desirable winemaking characteristics from loquat fruit fermentation broth. A total of 12 strains of P. kudriavzevii were isolated and subjected to morphological and molecular biological identification. Their fermentation performance, ethanol production, ester production, hydrogen sulfide production, killer activity, and tolerance were evaluated. The results revealed that strains Q-2, Q-9, Q-10, Q-12, Q-20, and Q-42 exhibited robust growth and strong tolerance under conditions of 40°C temperature, 12% ethanol concentration, 350g/L glucose concentration, and pH 2.8. Strain Q-42 demonstrated the strongest gas production capacity, killer activity, and good ester and ethanol production. As a highly active fermentation strain with excellent wine making characteristics, P. kudriavzevii Q-42 provides a valuable yeast resource for the industrial production of loquat wine and offers technical support for improving the overall quality of loquat wine.

Progress and Trends in Forage Cactus Silage Research: A Bibliometric Perspective

Opuntia spp. (forage cactus or spineless cactus) is a plant native to Mexico that is commonly used as alternative nutrient-rich fodder in semi-arid regions. Due to its resistance to drought, forage cactus has become an important least-cost ingredient for formulating balanced rations for ruminants during times of scarcity. In addition, ensiling, an anaerobic fermentation process, is also a strategy used to allow a supply of bulky food all year round, since it conserves forage and maintains its nutritional value. In this sense, using the Scopus database and the visualization tool VOSviewer, the present work proposes a bibliometric analysis of forage cactus silage to track and map the evolution and main issues in the research field, current trends, and future directions. The results revealed that the first publication was in 2013; and since 2020, the number of publications has been growing. Brazil was highlighted, by far, as the most relevant country on the topic, and the top institutions were from northeast Brazil, which has been working on co-authored articles. The current hot research topics are focusing on the mixed silage of forage cactus and other forages such as gliricidia, maniçoba, and sorghum biomass, as well as evaluating the fermentative performance and chemical characteristics for improving ruminal diets, especially for goats and sheep. This study provides important information for researchers to identify gaps and direct their studies to better use the whole potential of forage cactus as an alternative roughage source.