Search Results (3,770)

Accelerating urbanisation and industrial activity have led to the widespread release of polycyclic aromatic hydrocarbons (PAHs), a class of persistent organic pollutants with serious ecological and health consequences. While physical and chemical remediation techniques are widely used, they often require nonrenewable resources and generate secondary waste. Fungal-based bioremediation offers a promising alternative, leveraging the unique metabolic pathways and structural properties of fungi to break down or adsorb PAHs. This review focuses on three strategies of PAH remediation in aquatic environments: biofiltration, biosorption, and metabolic degradation. We conduct a comparison between conventional systems and fungal approaches with reference to the literature (2000–2025). Fungal matrices are identified as being able to capture and adsorb PAHs, facilitating localised remediation that capitalises on the biological capabilities of fungal organisms while requiring lower resource inputs than conventional methods. This review highlights fungal matrices as multifunctional water filtration membranes and provides insights for the application and development of engineered living materials (ELMs) for the water detoxification of PAHs. Full article

Fermented beverages have been highlighted for their beneficial effects on health, especially due to the presence of probiotic microorganisms. This study aimed to develop and characterize a beverage fermented from the aqueous extract of licuri (Syagrus coronata) with grains of milk kefir and water kefir. Physical–chemical properties, microbial viability, storage stability, and in vitro resistance to the gastrointestinal tract (GIT), as well as microbiological safety and identification of isolated bacteria, were evaluated. The grains were fermented in licuri for 24 and 48 h, and the samples were compared with their respective controls. The analyses revealed that the licuri drink favored the growth of kefir grains, maintaining adequate microbial viability (>7 log CFU mL⁻¹ for lactic acid bacteria and >4 log CFU mL⁻¹ for yeasts), with good resistance to GIT (>60%) and physical–chemical properties for 20 days. The bacterial isolate was identified as Lacticaseibacillus paracasei, with a satisfactory safety profile. Licuri extract is therefore a promising matrix for the development of non-dairy functional beverages with potential probiotic properties. Full article

P(3HB) is a biodegradable and biocompatible polymer, which can replace petroleum-derived plastics. Previous studies have shown that Azotobacter vinelandii strain OP-PhbP3⁺, which overexpresses the phasin protein PhbP3, produces high concentrations of P(3HB) and undergoes early autolysis, facilitating polymer release. The aim of the present study was to evaluate the performance of this strain for P(3HB) production in 3 L bioreactors and assess the feasibility of a simplified recovery process. After 36 h of cultivation, rapid cell lysis was observed, resulting in a ~50% decrease in the protein content of the cell dry weight, without reducing P(3HB) concentration, which reached 4.6 g L⁻¹. Flow cytometry analysis revealed significant morphological changes during cultivation, which was consistent with the strain’s lytic behavior. The biomass recovered at 36 h was washed with SDS, obtaining a yield of 92.5% (respect to P(3HB) initial) and a purity of 97.6%. An alternative extraction procedure using the non-halogenated solvent cyclohexanone (CYC) resulted in an even higher yield of 97.8% with a purity of 99.3% of P(3HB). Notably, the weight average molecular weight of the polymer remained stable at 8000 kDa during the entire process. Overall, the combination of PhbP3 over-expression and environmentally friendly solvents, such as CYC, enabled efficient P(3HB) production with high yield and purity while preserving polymer quality. Full article

The aim of this work was to study the effects of modification of the skin maceration process by adding ascorbic acid and a yeast culture of Saccharomyces cerevisiae on the quality and safety of Welschriesling wine. The pH, total acids, SO₂, and alcohol content were significantly affected by the modification of the maceration (p < 0.001), except for the alcohol variable, which was not influenced by the skin maceration modifications of the measured values (p > 0.05). The antioxidant activity, total polyphenols, flavonoids, and ascorbic acid levels changed significantly during the experiment, including the maceration and maturation periods (p < 0.001). The observed histamine concentrations were below the recommended limit of 10 mg·L⁻¹ in each analysed sample. Histamine (HIS) and tyramine (TYR) amounts were significantly affected by the experimental factors (p < 0.001). After nine months of maturation, wine samples with ascorbic acid had 2.23 ± 0.00 and 0.35 ± 0.00 mg·L⁻¹ HIS and TYR content, respectively. On the other side, macerated wines without ascorbic acid had 3.05 ± 0.10 and 0.37 ± 0.05 mg·L⁻¹ HIS and TYR content, respectively. Modified vinification procedure with ascorbic acid negatively affected wine samples in the overall sensory evaluation scores of the wines (p < 0.001). Full article

The study compared the effects of conventional and vegan processing aids in the clarification of must, focusing on the phenolic and sensory characteristics of must and wine. The hypothesis was that plant protein could provide results similar to those of conventional aids containing proteins of animal origin, especially in aromatic grapes, where hyperoxidation is avoided. Conducted in 2024 in Etyek-Buda, Hungary, the initial trials subjected the Irsai Olivér grape must to gravity sedimentation with various agents. Vegan processing aids, notably the combination of pea protein and chitin-glucan, showed a gentle impact on the assimilable nitrogen content and a similar reduction in turbidity to those with animal proteins. Nitrogen flotation trials compared gelatin and the vegan alternative (a combination of pea protein and chitin–glucan) in Irsai Olivér and Chardonnay must clarification. The removal of phenolic substances was monitored using the Folin–Ciocalteu method, the acid butanol assay, and the vanillin assay. In addition, nitrogen levels were evaluated before and after the flotation experiments. The plant-based processing aid effectively improved the sensory quality of Irsai Olivér. However, the gelatin-treated Chardonnay was fresher and less bitter than the vegan option, which was less balanced and more bitter with weaker aroma and flavor. Full article

Global warming has become a significant public health concern, with intensive livestock farming as a major contributor. To mitigate greenhouse gas emissions, strategies such as manipulating the ruminal environment with dietary additives are essential. This study evaluated Moringa oleifera, a globally widespread tree with antioxidant, multivitamin, protein-rich, and anti-inflammatory properties, as a feed additive. Rumen fluid was collected from three Pelibuey sheep, homogenized, and subjected to an in vitro fermentation study for 48 h with three alfalfa/moringa ratio treatments: T0 Control (100:0), T1 Low (85:15), and T2 High (70:30). Total RNA was extracted, followed by high-definition sequencing of the metatranscriptome. The sequencing yielded approximately 456 million sequences. A total of 117 phyla were identified and approximately 1300 genera were mapped. Predominant phylum differed by treatment: T0, Firmicutes; T1, Proteobacteria; and T2 with Synergistetes, at least one sample per treatment. Archaea were nearly absent in T1, which explains a statistically significant decrease in methane production. In the Gene Set Enrichment Analysis (GSEA), it was observed that one of the metabolic pathways with a statistically significant difference (p-value < 0.05) was that of methane, specifically in the low moringa treatment (T1) compared to the control (T0). From the functional analysis, differentially expressed enzymes were identified, some of which are involved in the methane metabolic pathway, such as formate dehydrogenase (EC 1.17.1.9) and glycine hydroxymethyltransferase (EC 2.1.2.1), which are intermediates in methane formation. These results suggest that 15% Moringa oleifera supplementation alters ruminal microbiota, reduces archaeal activity, and suppresses methane-related pathways. These findings provide molecular evidence supporting the potential of M. oleifera as a methane mitigation strategy in ruminant nutrition. Full article

The growing demand for aquaculture has driven the search for sustainable practices and utilization of agro-industrial residues. Brown rice bran, an abundant and low-cost by-product, has emerged as a promising raw material. This dissertation aimed to evaluate solid-state fermentation (SSF) of rice bran using the fungus Rhizopus oryzae and the yeast Saccharomyces cerevisiae with the goal of improving its nutritional value for use in diets formulated for zebrafish (Danio rerio). Proximate composition analyses revealed the strong biotransformation potential of Rhizopus oryzae. Fermentation with this fungus resulted in a significant 36.45% increase in protein content, a 51.62% increase in total polyphenols, and a 13.7% reduction in lipid content. In an in vivo experiment, zebrafish fed a diet containing rice bran fermented by R. oryzae showed the best zootechnical performance, with higher weight gain, specific growth rate, and improved feed conversion. Gene expression analysis showed a significant difference only for glut6, which is related to glucose transport. In summary, the fermentation of brown rice bran with Rhizopus oryzae represents an effective strategy to enhance its nutritional profile, establishing it as a viable alternative for the formulation of more sustainable and efficient diets in aquaculture. Full article

This study proposed a biosafe strategy to prevent staphylococcal enterotoxin production in cooked bacon, particularly in microenvironments at the product–package interface that may favor toxinogenesis. Challenge tests were conducted on bacon samples with varying water activity, inoculated with Staphylococcus aureus, and treated with a biopreservative produced in an axenic cultivation of Lacticaseibacillus paracasei DTA-83. Staphylococcal enterotoxin production was assessed using an ELISA test. Data about microbial growth and staphylococcal enterotoxin production were evaluated under simulated storage using the MicroLab_ShelfLife protocol. Results showed that staphylococcal enterotoxin production occurred independently of water activity, indicating that it alone does not ensure microbial safety. Even at a water activity level traditionally considered inhibitory, enterotoxin formation was observed, emphasizing the critical role of the product–package interface. However, a 1.0% biopreservative applied to the product surface effectively inhibited S. aureus growth and completely suppressed staphylococcal enterotoxin production under all conditions, including temperature abuse. In conclusion, the formation of enterotoxin by S. aureus at low water activity reveals a critical safety risk at the product–package interface. Targeted application of a 1.0% biopreservative at this vulnerable site proved highly effective, reinforcing its role as a practical and non-intrusive hurdle strategy to enhance microbial safety in shelf-stable meat products. Full article

The fermentation performance of Lactobacillus acidophilus is constrained by factors such as low cell density and fastidious nutritional and environmental requirements, which greatly limit its industrial-scale applications. This study aimed to develop an efficient fermentation condition for L. acidophilus CCFM137 through systematic optimization of both culture medium and environmental parameters, thereby enabling high-yield industrial-scale production of this strain. An optimized medium was developed, consisting of glucose (30 g/L), YEP FM503 (35 g/L), sodium acetate (5 g/L), ammonium citrate (2 g/L), K₂HPO₄ (2 g/L), MgSO₄·7H₂O (0.1 g/L), MnSO₄·H₂O (0.05 g/L), L-cysteine hydrochloride (0.5 g/L), and Tween 80 (1 mL/L), to achieve a viable cell count of 1.95 × 10⁹ CFU/mL, representing a 9.42-fold increase over that of standard MRS broth. Subsequent pH-stat fermentation trials in a 100 L fermenter using the optimized medium revealed morphological and growth characteristics of the strain in variable pH-stat environments. Optimal performance was observed under pH-stat 4.5 rather than the more commonly used 5.7, achieving maximum viable cell counts of 3.37 × 10⁹ CFU/mL, accompanied by a transformation of cell morphology toward shorter rod-shaped structures, as well as an increase in substrate utilization rate, cell recovery rate and lyophilization survival rate. The fermentation performance and cellular morphology of L. acidophilus CCFM137 were enhanced by both nutrient composition and pH environment. These results showed that this strategy has potential for application in high cell density fermentation of L. acidophilus CCFM137. Full article

Bioethanol manifests an extraordinary potential to overcome the severe energy crises and reliance on fossil fuels, yet it supports the sustainable and cost-effective production of fuels for automobile engines and contributes to the reduction of greenhouse gas (GHG) emissions and other global climate-related challenges. The present study examines the potential of Mixed Lignocellulosic Biomass (MLB) as a sustainable feedstock for the consistent year-round production of bioethanol. The primary MLB sources considered in this research to underscore the significance of this heterogeneous strategy include sweet sorghum bagasse (SSB), sugarcane bagasse (SCB), and date palm trunk (DPT). Each of the three feedstocks, i.e., SSB, SCB, and DPT, were individually subjected to alkaline pretreatment, a step aimed at breaking down structural barriers and facilitating greater release of fermentable sugars during fermentation. Likewise, the alkaline-pretreated biomasses were subjected to simultaneous saccharification and fermentation (SSF) for 96 h, both individually as well as in various combined proportions. Individually, pretreated sweet sorghum bagasse (SSB) fibers produced the highest ethanol concentration, of 30.79 ± 0.44 g/L; an ethanol yield of 0.40 ± 0.62 g/g; an ethanol productivity of 0.42 ± 0.87 g/L/h; and a theoretical ethanol yield of 79.81% at 72 h. In contrast, the combination of MLB (50% of pretreated SSB and 50% of DPT fibers) produced a significantly higher ethanol concentration of 31.47 ± 0.57 g/L and an ethanol productivity of 0.653 ± 0.24 g/L/h in much less time, i.e., 48 h of SSF fermentation. The empirical data confirms that MLB offers a sustainable paradigm for ethanol biosynthesis by curtailing fermentation time and optimizing economic and operational efficacy. Full article

Lignocellulosic agro-forestry residues (LARs), such as rice straw, sugarcane bagasse, and wood wastes, are abundant and low-cost feedstocks for polyhydroxyalkanoate (PHA) bioplastics. However, their complex cellulose–hemicellulose–lignin matrix requires integrated valorization strategies. This review presents a dual-framework approach: “pretreatment–co-substrate compatibility” and “pretreatment–microbial platform matching”, to align advanced pretreatment methods (including deacetylation–microwave integration, deep eutectic solvents, and non-sterilized lignin recovery) with engineered or extremophilic microbial hosts. A “metabolic interaction” perspective on co-substrate fermentation, encompassing dynamic carbon flux allocation, synthetic consortia cooperation, and one-pot process coupling, is used to elevate PHA titers and tailor copolymer composition. In addition, we synthesize comprehensive kinetic analyses from the literature that elucidate microbial growth, substrate consumption, and dynamic carbon flux allocation under feast–famine conditions, thereby informing process optimization and scalability. Microbial platforms are reclassified as broad-substrate, process-compatible, or product-customized categories to emphasize adaptive evolution, CRISPR-guided precision design, and consortia engineering. Finally, next-generation techno-economic analyses, embracing multi-product integration, regional adaptation, and carbon-efficiency metrics, are surveyed to chart viable paths for scaling LAR-to-PHA into circular bioeconomy manufacturing. Full article

This study presents the production, characterization, and potential pharmaceutical application of a bioemulsifier synthesized by Aspergillus niger UCP 1064 by submerged fermentation using agro-industrial residues (cassava wastewater and soluble starch). The compound exhibited a high emulsification index (EI₂₄ > 88%) against hydrophobic substrates, effectively reduced surface tension, and remained stable across a wide range of pH (2–12), temperatures (5–100 °C), and salinity levels (0–20% NaCl). Microscopic analysis confirmed the formation of stable oil-in-water (O/W) emulsions, while biochemical tests identified the compound as a glycolipoprotein. Rheological assays demonstrated a significant reduction in oil viscosity, enhancing fluidity. Through factorial design and response surface methodology, production conditions were optimized, achieving yields of up to 3.18 g/L. A theoretical scale-up indicated technical feasibility for pharmaceutical applications; however, challenges such as process reproducibility, sterility, and regulatory compliance persist. These findings highlight the bioemulsifier’s potential as a sustainable and biocompatible alternative for drug delivery systems. Full article

This study presents an integrated valorization strategy for oat husks through microwave-assisted pretreatment using a deep eutectic solvent (DES) composed of choline chloride and glycerol (1:2). The process was designed to enhance the release of fermentable sugars, enable xylooligosaccharide (XOS) production, and support inulinase production by Aspergillus niger A42 via submerged fermentation of the hydrolysate and solid-state fermentation of the residual biomass. Response surface methodology (RSM) was applied to evaluate the effects of microwave power, treatment time, and liquid-to-solid ratio (LSR) on fermentable sugar content (FSC) and total phenolic compounds (TPCs). Following pretreatment, the biomass was hydrolyzed using 1.99% sulfuric acid for 1 min. Optimal pretreatment conditions (350 W, 30 s, LSR 4 w/w) yielded an FSC of 51.14 g/L. Additionally, 230.78 mg/L xylohexaose and 6.47 mg/L xylotetraose were detected. Submerged fermentation of the liquid fraction with A. niger A42 resulted in inulinase and invertase activities of 60.45 U/mL and 21.83 U/mL, respectively. Solid-state fermentation of the pretreated solids produced 37.03 U/mL inulinase and 17.64 U/mL invertase. The integration of microwave-assisted DES pretreatment, dilute acid hydrolysis, and fungal fermentation established a robust strategy for the sequential production of XOS, fermentable sugars, and inulinase from oat husks, supporting their comprehensive utilization within a sustainable biorefinery framework. Full article

The aim of this study was to develop fermented milks using strains of lactic acid bacteria with probiotic potential isolated from Minas artisanal cheese. For this purpose, the strains Lacticaseibacillus casei B5 and Lactiplantibacillus plantarum B7 were used in a 6 × 4 experimental design, with six fermented milk treatments and four analyses on days 1, 15, 30 and 45 to characterize the product and evaluate the viability of the bacteria. Additionally, a sensory analysis was conducted using a preference ranking test. All treatments showed viable counts of microorganisms above 10⁶ CFU/mL until the end of the storage period, as well as variations in pH and titratable acidity values on day 45, being the lowest value of both verified in the TRAT1B7 sample. Based on the application of a sensory analysis, it was observed that the type of treatment and the strain directly impacted the sample chosen by the tasters. According to results gathered from the present study, milk fermented by L. casei B5 stands out in the order of preference, however milk fermented by L. plantarum B7 has also obtained favorable results, indicating that this strain of bacteria can be used in dairy technology. Full article

Okara, a protein-rich byproduct of soymilk production, is highly perishable because of its high moisture content. This study evaluated the preservation and nutritional value of okara fermented by lactic acid bacteria for use in dairy cattle diets. Fermentation effectively reduced pH within 2 weeks and maintained quality for up to 6 weeks. However, aerobic exposure increased the concentration of ammonia, indicating a decline in stability. In vitro assessments revealed no significant differences in in vitro true dry matter digestibility, in vitro neutral detergent fiber digestibility, or gas production between fermented and fresh okara, although fermented okara had a higher concentration of ammonia nitrogen. In situ analysis revealed slightly lower dry matter effective degradability (ED) in fermented okara, but similar rumen-degradable and undegradable protein fractions. When fermented okara was used to replace soybean meal in total mixed rations, 25–50% inclusion-maintained digestibility and fermentation characteristics, with 25% replacement yielding the highest ED at a low ruminal passage rate (0.02 h⁻¹). Taken together, these results suggest that fermented okara can be strategically incorporated into dairy rations as a sustainable protein alternative, supporting both rumen function and bypass protein supply. Full article