Search Results (12,265)

This study investigated the impact of tea polyphenols on serum indices, rumen microorganisms, rumen metabolism, and liver metabolism in Hu sheep. Sixty healthy lambs, aged three months and with similar average weights, were chosen and randomly assigned to control (CON), TP400, TP800, and TP1200 groups, each consisting of fifteen lambs. The control group received a basal diet, while the experimental groups were provided with basal diet supplemented with 400 mg/kg, 800 mg/kg, and 1200 mg/kg of tea polyphenols, respectively. Compared with the CON group, the addition of tea polyphenols to the diet significantly increased serum IgA, GSH−Px, and TSOD. In addition, tea polyphenols were able to increase rumen pH but had no significant effect on the rumen NH₃−N, VFA molar content, and the microbial top 10 phylum and genus levels. Moreover, Firmicutes predominated in the network map of the top 80 abundant microorganisms at the genus level, identifying 13 biomarkers at the genus level. In addition, strong correlations were observed between liver and rumen metabolites, particularly between rumen succinic acid and liver alanyl−serine and methylmalonic acid. Furthermore, tea polyphenol additions changed the enrichment of liver and rumen metabolites in the top five KEGG metabolic pathways, but 400−1200 mg/kg additions had no negative impact on the liver and rumen. In summary, TP significantly influences rumen and liver metabolites in Hu sheep, enhancing lamb immunity and antioxidant capacity, with 400 mg/kg being the most effective dosage. Full article

p-Coumaric acid (p-CA) is a valuable compound with applications in food additives, cosmetics, and pharmaceuticals. However, traditional production methods are often inefficient and unsustainable. This study focuses on enhancing p-CA production efficiency through the heterologous expression of tyrosine ammonia-lyase (TAL) from Rhodobacter sphaeroides in Pseudomonas putida KT2440. TAL catalyzes the conversion of L-tyrosine into p-CA and ammonia. We engineered P. putida KT2440 to express TAL in a fed-batch fermentation system. Our results demonstrate the following: (i) successful integration of the TAL gene into P. putida KT2440 and (ii) efficient bioconversion of L-tyrosine into p-CA (1381 mg/L) by implementing a pH shift from 7.0 to 8.5 during fed-batch fermentation. This approach highlights the viability of P. putida KT2440 as a host for TAL expression and the successful coupling of fermentation with the pH-shift-mediated bioconversion of L-tyrosine. Our findings underscore the potential of genetically modified P. putida for sustainable p-CA production and encourage further research to optimize bioconversion steps and fermentation conditions. Full article

Non-alcoholic fatty acid disease (NAFLD) is caused by a build-up of fat in the liver, inducing local inflammation and fibrosis. We evaluated the effects of probiotic lactic acid-generating bacteria (LAB) derived from a traditional fermented beverage in a mouse model of NAFLD. The LAB isolated from this traditional Korean beverage were screened using the human hepatic cell line HepG2, and Lactocaseibacillus paracasei HY7207 (HY7207), which was the most effective inhibitor of fat accumulation, was selected for further study. HY7207 showed stable productivity in industrial-scale culture. Whole-genome sequencing of HY7207 revealed that the genome was 2.88 Mbp long, with 46.43% GC contents and 2778 predicted protein-coding DNA sequences (CDSs). HY7207 reduced the expression of lipogenesis and hepatic apoptosis-related genes in HepG2 cells treated with palmitic acid. Furthermore, the administration of 10⁹ CFU/kg/day of HY7207 for 8 weeks to mice fed an NAFLD-inducing diet improved their physiologic and serum biochemical parameters and ameliorated their hepatic steatosis. In addition, HY7207 reduced the hepatic expression of genes important for lipogenesis (Srebp1c, Fasn, C/ebpa, Pparg, and Acaca), inflammation (Tnf, Il1b, and Ccl2), and fibrosis (Col1a1, Tgfb1, and Timp1). Finally, HY7207 affected the expression of the apoptosis-related genes Bax (encoding Bcl2 associated X, an apoptosis regulator) and Bcl2 (encoding B-cell lymphoma protein 2) in the liver. These data suggest that HY7207 consumption ameliorates NAFLD in mice through effects on liver steatosis, inflammation, fibrosis, and hepatic apoptosis. Thus, L. paracasei HY7207 may be suitable for use as a functional food supplement for patients with NAFLD. Full article

The presented research addresses a problem occurring in a biogas plant, which we know plays an important role in sustainable development. The sludge deposited on the walls of the digester’s heat exchanger impairs heat transfer to the substrate. It leads to a temperature drop inside the biogas plant and threatens its correct operation. The thickness of the sludge layer cannot be directly measured when the plant is operating. Therefore, the aim of this work was to develop and then validate a method for estimating, based on the operating parameters of the exchanger, the thickness of the sludge layer and to give theoretical foundations for designing an automatic sludge monitoring system. Two mathematical models (and methods) were developed: one- and two-dimensional. The former model was solved analytically while the latter by the Trefftz method. The numerical results from these two approaches showed very good agreement with each other and with the actual measurement taken directly after removing the substrate from the fermentation chamber. According to the calculation results, the growth of the sludge layer was linear with time, and its rate was 0.0064 mm per day. Finally, a schematic diagram of an intended sludge monitoring system was proposed. It could optimize biogas plant operation and thus become a step towards more sustainable energy production. Full article

Corn husk, a by-product of corn starch production and processing, contains high-quality dietary fiber (DF). Our study compares and analyzes the impact of Hericium erinaceus solid-state fermentation (SSF) on the structure and physicochemical characteristics of soluble dietary fiber (SDF) of corn husks. The study also investigates the kinetics of SSF of H. erinaceus in this process. The scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) results revealed significant structural changes in corn husk SDF before and after fermentation, with a significant elevation in the functional group numbers. The data indicate that the fermented corn husk SDF’s water-holding, swelling, and oil-holding capacities increased to 1.57, 1.95, and 1.80 times those of the pre-fermentation SDF, respectively. Additionally, the results suggest that changes in extracellular enzyme activity and nutrient composition during SSF of H. erinaceus are closely associated with the mycelium growth stage, with a mutual promotion or inhibition relationship between the two. Our study offers a foundation for corn husk SDF fermentation and is relevant to the bioconversion of maize processing by-products. Full article

Kefiran is a heteropolysaccharide that is considered a postbiotic and is obtained by kefir grains fermented in cow’s milk, while little is known about the donkey milk (DM) variety. Postbiotics are recognised as having important human health benefits that are very similar to probiotics but without the negative effects associated with their ingestion. Donkey is a monogastric animal, as are humans, and when used as an alternative food for infants who suffer from cow milk protein allergies, DM could therefore display more biocompatibility. In this study, the DM kefiran was extracted by ultrasound from kefir grains cultured in donkey milk and fully characterized for its structural and physicochemical properties by Fourier-transform infrared spectroscopy (FT-IR), High-Performance Liquid Chromatography- Refractive Index (HPLC-RI), Scanning electron microscope (SEM), Differential Scanning Calorimeters (DSC) and rheological analyses. In addition, tests were conducted on keratinocytes cell lines and human red blood cells to assess the nontoxicity and haemolysis degree of the polymer. The extraction yield of the DM kefiran was 6.5 ± 0.15%. The FT-IR analysis confirmed the structure of the polysaccharide by showing that the stretching of the C-O-C and C-O bonds in the ring, which formed two bands at 1157 and 1071 cm⁻¹, respectively, and the anomeric band at 896 cm⁻¹ indicates the β configuration and vibrational modes of glucose and galactose. Results were confirmed by HPLC-RI analysis indicating that the ratio glucose/galactose was 1:0.87. Furthermore, the SEM analysis showed a porous and homogeneous structure. The rheological analysis confirmed the pseudoplastic nature of the polymer, while the DSC analysis highlighted excellent thermal resistance (324 °C). Finally, DM kefiran was revealed to have biologically acceptable toxicity, showing a haemolytic activity of less than 2% when using fresh human red blood cells and showing no cytotoxicity on human keratinocytes. Therefore, kefiran obtained by DM shows an excellent biocompatibility, establishing it as a promising polymer for bioengineering human tissue for regenerative applications. Full article

The Inner Mongolia Autonomous Region, known for its famous Mongolian horses, faces significant environmental challenges due to the large-scale rearing of these animals, which produces a substantial amount of manure. If not managed effectively, this manure can lead to severe environmental pollution. The aim of this study was to investigate whether a small-scale intelligent aeration and heating composting system is effective in treating Mongolian horse manure, with the objective of enhancing composting efficiency and resource utilization to support sustainable agricultural development in the region. The equipment was utilized to treat a compost mixture of Mongolian horse manure and corn stover, allowing for an analysis of the changes in key indicators throughout the composting process. The results demonstrated that the equipment maintained high temperatures for up to eight days during the composting process, effectively inactivating pathogens and promoting the efficient decomposition of organic matter. The system also successfully controlled humidity to 12.7% and maintained oxygen concentration within the optimal range. Post-composting analysis revealed that the final compost contained 2.3% nitrogen, 1.3% phosphorus, and 1.2% potassium, with a pH of 6.4 and conductivity of approximately 5.2 mS/cm. Additionally, the carbon-to-nitrogen ratio decreased significantly from 27.3 to 15.9, indicating substantial organic matter degradation. Seed germination tests showed germination rates of 80%, 86%, and 75% for corn, mung bean, and wheat, respectively, with a final seed germination index of 104%. This study concluded that the small aeration and heating composting equipment is highly effective in treating Mongolian horse manure, producing high-quality organic fertilizers that significantly enhance soil fertility and demonstrate considerable potential for supporting sustainable agricultural practices and improving environmental management in the Inner Mongolia Autonomous Region. Full article

Mandarin peel (MP) has gained attention as a feedstock for flavonoid recovery via the extraction process based on the biorefinery concept, but residues remain after the extraction. Toward an integrated biorefinery concept, this study aimed to valorize extracted MP (eMP) by using it in bioethanol production. For efficient fermentable sugar production, the effect of enzymatic hydrolysis conditions on sugar conversion from eMP was investigated, and the results showed that combining cellulase and cellobiase resulted in a higher enzymatic glucose conversion (78.2%) than the use of the individual enzymes (37.5% and 45.6%). Pectinase played an essential role in enhancing enzymatic arabinose conversion, and the optimal conditions were determined to be pH 4 and 90 units of the three enzymes. Under optimal conditions, the sugar yield was 199 g glucose and 47 g arabinose/kg eMP, and the hydrolysate was used in bioethanol fermentation. The results showed that the bioethanol production was 3.78 g/L (73.9% yield), similar to the control medium (3.79 g/L; 74.2% yield), although the cell growth of the yeast was slightly delayed in the eMP hydrolysate medium. This study highlights the potential of eMP as a low-cost feedstock for sugar and bioethanol production. Full article

Oil spills occur during different operations in the energy sector, such as crude oil transport, tank filling and cleaning, and fueling. Such spills are one of the major causes of the accumulation of oil derivatives in the environment, requiring the remediation of soil and marine environments. The production of a biosurfactant by Starmerella bombicola ATCC 222214 was maximized by investigating the effect of different carbon/nitrogen sources and culture conditions. The mineral medium selected for its production was supplemented with 2.0% potato peel flour, 5.0% waste canola frying oil, and 0.20% urea. The culture conditions were a 200 rpm shaking speed, a fermentation time of 180 h, and a 4.0% inoculum size. The yield of isolated biosurfactant was 7.72 g/L. The emulsification rates of heavy oil and motor oil were 65.55 and 95.00%, respectively, indicating an affinity for complex hydrocarbons. In stability tests performed at different pH values, temperatures, and NaCl concentrations, the surface tension ranged from 27.14 to 31.08 mN/m. The critical micelle concentration was 2.0 g/L, at which the surface tension was 33.26 mN/m. The biosurfactant was composed of 6,6-dimethoxy-octanoic acid and azelaic acid, and it exhibited low toxicity to Brassica oleracea and Solanum lycopersicum. In the kinetic test, the biosurfactant allowed for the removal of 82.30%, 96.65%, and 98.25% of exhaust motor oil from sand, silty soil, and clay soil, while in the static test in packed columns, the removal yields were 66.62%, 63.03%, and 58.45%, respectively. The biosurfactant produced in this study is promising for environmental remediation applications in the energy sector. Full article

Odor emissions from animal manure present a significant environmental challenge in livestock farming, impacting air quality and farm sustainability. Traditional methods, such as chemical additives and manure treatment, can be costly, labor-intensive, and less eco-friendly. Therefore, this study investigated the effectiveness of microbial feed additives in reducing these odors. Conducted over three months in 2022 on a Korean beef cattle farm with 20 cattle, the experiment involved feeding a mixture of four microbial strains—Bacillus subtilis KNU-11, Lactobacillus acidophilus KNU-02, Lactobacillus casei KNU-12, and Saccharomyces cerevisiae KNU-06. Manure samples were collected from an experimental group (n = 9) and a control group (n = 11), with microbial community changes assessed through 16S ribosomal RNA gene amplicon sequencing. The results demonstrated significant reductions in specific odorous compounds in the experimental group compared to the control group: ammonia decreased by 64.1%, dimethyl sulfide by 81.3%, butyric acid by 84.6%, and isovaleric acid by 49.8%. Additionally, there was a notable shift in the microbiome, with an increase in the relative abundance of Ruminococcaceae and Prevotellaceae microbes associated with fiver degradation and fermentation, while the control group had higher levels of Bacteroidota and Spirochaetota, which are linked to pathogenicity. This study demonstrates that probiotics effectively alter intestinal microbiota to enhance microorganisms associated with odor mitigation, offering a promising and more sustainable approach to reducing odor emissions in livestock farming. Full article

Chinese Baijiu is a famous fermented alcoholic beverage in China. Interactions between key microorganisms, i.e., Saccharomyces cerevisiae and Lactiplantibacillus plantarum, have recently been reported at specific temperatures. However, empirical evidence of their interactions at various temperatures during fermentation is lacking. The results of this study demonstrated that S. cerevisiae significantly suppressed the viability and lactic acid yield of L. plantarum when they were cocultured above 15 °C. On the other hand, L. plantarum had no pronounced effect on the growth and ethanol yield of S. cerevisiae in coculture systems. S. cerevisiae was the main reducing sugar consumer. Inhibition of lactic acid production was also observed when elevated cell density of L. plantarum was introduced into the coculture system. A proteomic analysis indicated that the enzymes involved in glycolysis, lactate dehydrogenase, and proteins related to phosphoribosyl diphosphate, ribosome, and aminoacyl-tRNA biosynthesis in L. plantarum were less abundant in the coculture system. Collectively, our data demonstrated the antagonistic effect of S. cerevisiae on L. plantarum and provided insights for effective process management in light-flavor Baijiu fermentation. Full article

An amylolytic industrial yeast strain named 1974-GA-temA, developed previously by our research team by coexpressing the α-amylase and glucoamylase genes, combines enzyme production, sweet potato residue (SPR) hydrolysis, and glucose fermentation into ethanol in a one-step process. This consolidated bioprocessing (CBP) method has great application potential in the commercial production of bioethanol from SPR, but important fermentation parameters should be optimized to further increase the ethanol concentration and yield. In this study, the effects of the initial fermentation pH, solid-to-liquid ratio, inoculation volume, addition of exogenous enzyme, and supplementation with metal ions were systemically investigated. Single-factor experiments revealed that the optimal pH was 4.0. In the solid-to-liquid ratio test, an increase in the solid-to-liquid ratio corresponded with a gradual increase in the ethanol concentration, peaking at 1:5. However, the ethanol yield gradually decreased, with the optimal solid-to-liquid ratio identified as 1:5. The ethanol concentration and yield reached 9.73 g/L and 5.84%, respectively. Additionally, an increase in the inoculum size resulted in increased ethanol concentration and yield, with the optimal inoculum level determined to be 10%. An ethanol concentration of 7.87 g/L was attained under these specified conditions, equating to an ethanol yield of 4.72%. Further analysis was conducted to assess the effects of exogenous cellulase, hemicellulase, and pectinase, both individually and in combination, on ethanol concentration and yield. The results indicated that pectinase had a particularly significant effect. The highest ethanol concentration was observed when all three enzymes were administered concurrently, yielding 27.27 g/L ethanol. Then, the role of metal ions in SPR fermentation was evaluated. The metal ions did not significantly affect the process, with the exception of copper ions. The addition of copper ions at a specific concentration of 0.2 g/100 g SPR increased the ethanol concentration. However, concentrations exceeding 0.2 g/100 g SPR inhibited yeast cell growth. Finally, orthogonal optimization was employed to determine the optimal combination of factors: pH, 4.0; solid-to-liquid ratio, 1:6; inoculation volume, 10%; cellulase and pectinase addition; and the absence of Cu²⁺ addition. Under these conditions, strain 1974-GA-temA produced 34.83 ± 0.62 g/L ethanol after 8 days of fermentation, corresponding to a 20.90% ± 0.37% ethanol yield. This value markedly exceeds the outcomes of all the conducted orthogonal experiments. The fermentation optimization experiments in this study are expected to increase ethanol production during the CBP fermentation of SPR. Full article

The by-products from three varieties of dates—Mozafati, Sayer, and Kabkab—were subjected to solid-state fermentation using Aspergillus niger alone or in co-culture with Lactiplantibacillus plantarum or Limosilactobacillus reuteri to enhance their phenolic and flavonoid content, along with antioxidant and antimicrobial activities. Solid-state fermentation, being environmentally friendly and cost-effective, is particularly suitable for agricultural residues. Significant increases (p < 0.05) in total polyphenol content (TPC), total flavonoid content (TFC), and antioxidant power were observed post-fermentation, especially under co-culture conditions. The highest TPC (12.98 ± 0.29 mg GA/g) and TFC (1.83 ± 0.07 mg QE/g) were recorded in the co-culture fermentation of by-products from the Mozafati and Sayer varieties, respectively. HPLC analysis revealed changes in polyphenol profiles post-fermentation, with reductions in gallic and ferulic acids and increases in caffeic acid, p-coumaric acid, rutin, quercetin, and kaempferol. FT-IR analysis confirmed significant alterations in polyphenolic functional groups. Enhanced antimicrobial activity was also observed, with inhibition zones ranging from 8.26 ± 0.06 mm for Kabkab to 17.73 ± 0.09 mm for Mozafati. These results suggest that co-culture solid-state fermentation is a promising strategy for valorizing date by-products, with potential applications in nutraceuticals and/or pharmaceutical products and as valuable additives in the food industry. Full article

In the last decade, the application of non-Saccharomyces yeasts in oenology as a natural tool to obtain wine diversification and higher quality has aroused great interest. In this work, three Metschnikowia pulcherrima strains, isolated from a vineyard, were characterised through the evaluation of their main oenological properties, antimicrobial activity, and specific enzymatic activities (β-glucosidase, β-lyase, polygalacturonase, and protease). The M. pulcherrima strains did not produce any inhibition against Saccharomyces cerevisiae, while they were able to exert an antimicrobial action against some unwanted bacteria and yeasts frequently present in grape must and potentially causing the alteration of wines. After this preliminary screening, M. pulcherrima AS3C1 has been selected to be used in the winemaking of red grape Vitis vinifera cv. Aglianico on a pilot scale. The effect of the sequential inoculation of M. pulcherrima AS3C1 with a commercial strain of S. cerevisiae was verified using for comparison a single inoculum with S. cerevisiae and a spontaneous fermentation. Our results showed a higher concentration of anthocyanins and catechins in wines obtained by the sequential inoculation of M. pulcherrima AS3C1 and S. cerevisiae. On the basis of the data obtained, M. pulcherrima AS3C1 possesses an enzymatic profile and some oenological properties that could contribute positively to the definition of the chemical composition of wines, suggesting its possible use for red winemaking processes. Full article

Pear black spot, caused by A. gaisen during fruit growth, is a disease that significantly reduces pear yield. Biological control using antagonistic microorganisms is regarded as a viable alternative to chemical agents. The discovery of TRM76147, a novel species of Streptomyces isolated from the Taklamakan Desert, has demonstrated promising potential in addressing this issue. This study was conducted to determine the potential of crude extract of Streptomyces sp. nov., strain TRM76147, for control of A. gaisen. TRM76147 is closely related to Streptomyces griseoviridis NBRC 12874^T, exhibiting an average nucleotide identity (ANI) value of 82.13%. Combined with the polyphasic taxonomic identification, this suggests that TRM76147 is a potentially new species. Through analyses using BigSCAPE and antiSMASH, it was determined that the TRM76147 genome contains 19 gene clusters. The ethyl acetate extract of this strain demonstrates antifungal activity, with the active substance remaining stable at temperatures up to 70 °C, achieving an activity level of 16.23 ± 0.22 mm. Furthermore, the crude extract maintains its antifungal efficacy across a pH range of 2 to 12. Notably, the antifungal diameter was recorded at 16.53 ± 0.12 mm following 80 min of UV irradiation. Under different treatment conditions, TRM76147 fermentation crude extract caused A. gaisen spore crumpling and spore number reduction. In addition, this study also found that the TRM76147 fermentation broth could control the production of pear black spot disease, which initially revealed the inhibition mechanism. The abundant actinomycete resources in this study have good application and development value in the discovery of new species and the study of bioactive substances and biological control. Full article