Search Results (142)

Soil pore architecture and hydraulic functioning strongly regulate water flow and retention. However, despite the growing application of X-ray computed tomography (X-ray CT) in soil science, its application in characterizing the pore system and hydraulic functioning of native forest soils converted to sugarcane production systems in northeast Brazil is still poorly known. This study therefore quantified the soil structure, pore system, and hydraulic functioning of a native forest (NF) and an adjacent sugarcane field receiving vinasse and managed without intercropping (sole sugarcane (SG)) and with Brachiaria ruziziensis intercropping (SG + Bra intercrop) in northeastern Brazil, using conventional soil physical measurements and X-ray CT, in three soil layers (0–10, 10–20, and 20–40 cm). Soil physical and hydraulic properties, as well as soil water retention, were quantified. The native forest soil exhibited a uniformly sandy texture across all depths, whereas sugarcane systems ranged from loam to sandy textures in surface layers due to long-term management. Soil organic matter and total nitrogen in the 0–10 cm layer were approximately 75 and 65% higher, respectively, in sole Sole SG and SG + Bra intercrop than in NF. Soil bulk density increased with depth under sugarcane, reaching values about 10%–13% higher than NF in the 20–40 cm layer. Saturated hydraulic conductivity in the surface layer was higher in the NF, approximately five to nine times greater than in sole SG and SG + Bra intercrop, respectively. Conventional water retention analysis showed that sole SG and SG + Bra intercrop had greater total porosity (0.49–0.55 m³ m⁻³), microporosity (0.26–0.36 m³ m⁻³), field capacity (0.19–0.33 m³ m⁻³), and plant available water (0.09–0.15 m³ m⁻³) in the upper 20 cm compared with the NF (≤0.10 m³ m⁻³ available water). In contrast, X-ray CT revealed higher macroporosity (0.20–0.23 mm³ mm⁻³) and pore connectivity in the NF across all depths, with predominantly complex, inclined to near-horizontal pores and low anisotropy. Intercropping sugarcane with Brachiaria did not significantly alter (p > 0.05) bulk density, hydraulic conductivity, or CT-derived pore connectivity relative to sole sugarcane. The degree of anisotropy and fractal dimension derived from X-ray CT were significantly correlated (p < 0.05) with conventionally measured hydraulic properties. The X-ray computed tomography proved effective in linking pore-scale architecture to soil hydraulic functioning, providing insights beyond conventional measurements. The short-term inclusion of Brachiaria as a cover crop at 10 kg seed ha⁻¹ did not result in significant improvements in soil pore structure, indicating that longer-term adoption and/or higher planting densities may be required to induce measurable changes in pore system architecture and soil hydraulic functioning. Full article

The management of Pig Slurry (PS) and Wine Vinasse (WV) poses major environmental and economic challenges, Anaerobic co-digestion (AcoD) offers a promising approach, producing both renewable energy and nutrient-rich digestates with agronomic potential. This study evaluated digestates obtained from the AcoD of a 50:50 mixture of pig slurry and wine vinasse under Temperature-Phased Anaerobic Digestion (TPAD) conditions. The acidogenic reactor reached stability at a hydraulic retention time (HRT) of 5 days, achieving 51.34 ± 3.08% of tCOD removal and approximately 0.5 L of daily green hydrogen production, whereas the methanogenic stage reached stability at an HRT of 10 days with 89.14 ± 2.33% tCOD removal and recording daily biomethane production of up to 1 L. Digestates were tested in germination assays using Lepidium sativum (garden cress), Lactuca sativa (lettuce), and Raphanus sativus (radish) seeds to assess phytotoxicity, and pathogen analyses were conducted to confirm sanitary safety (contains 0.8 × 10³ MPN/gTS E. coli). Results showed that agronomic performance was primarily influenced by dilution level, at 10D–15D% dilutions, germination and root growth remained stable, with Germination Index (GI) values above 80%. In contrast, concentrations above 25D% led to marked inhibition, with GI values below 50%. These findings demonstrate that the TPAD system operates effectively when treating pig slurry and winery vinasse, producing digestates that are safe and effective organic amendments. Moreover, given their compliance with sanitary standards, these digestates can be classified as Class A biosolids suitable for agricultural application, provided that adequate dilution is ensured. Full article

In laboratory installations, wastewater from the distillery industry (ethanol stillage and vinasse) is treated via a two-stage combination of microbial sulfate reduction (MSR) and biomethanation, assisted by bioelectrochemical systems (BESs). In the first stage, a sulfidogenic bioreactor with an integrated microbial fuel cell (MFC) is used, which partially oxidizes the produced H₂S and facilitates the conversion of organic compounds. Sulfate removal reaches 95.4% (stillage) and 92.8% (vinasse), with corresponding COD reductions of 30.6% and 36.5%, respectively. The polarization curves, power density, generated current, and coulombic efficiency are analyzed. The sulfidogenic bioreactor consortium is dominated by Deltaproteobacteria, which contributes to acetate accumulation during the MSR stage. Methanogens are dominated by the genus Methanofolis. In the second stage of anaerobic digestion, three treatment options are investigated: direct biomethanation, biomethanation after preliminary MSR, and biomethanation after MSR with a microbial electrolysis cell (AD-MEC). The highest COD conversion rates are achieved in the AD-MEC variants: 91.36% for ethanol stillage and 92.8% for vinasse. Microbial communities are dominated by acetoclastic methanogens of the genus Methanothrix. For stillage treated after MSR, biogas production is nearly double that from direct methanation. For vinasse, the largest amount of biogas is generated during by the integrated MEC system, followed direct methanation. Methane content is the highest in methanation after MSR in AD-MEC (93.4–93.6%). Full article

Sugarcane vinasse is a high-strength effluent with a high organic load and intense coloration from melanoidins and phenolic compounds, making conventional biological treatment difficult. This study presents a magnetically recoverable Fe₃O₄@latex-ZnO nanocomposite, synthesized using natural Hevea brasiliensis latex as a green polymeric interlayer. Transmission Electron Microscopy (TEM) shows a core–shell structure that enhances ZnO anchoring and reduces aggregation. X-ray Diffraction (XRD) confirms the coexistence of spinel Fe₃O₄ and wurtzite ZnO without secondary phases, while Fourier Transformed Infrared Spectroscopy (FTIR) verifies the latex layer through characteristic organic bands, indicating a stable organic–inorganic interface. Under 4 h of UV irradiation, the nanocomposite significantly reduced vinasse COD from 23,450 to 12,450–13,150 mg L⁻¹ (≈44–47%) and BOD from 11,600 to 4800–5000 mg L⁻¹ (≈57–59%), demonstrating substantial oxidation of the organic fraction. The magnetic core enables quick separation post-treatment, enhancing the practicality of the process. Overall, this innovative approach positions the ZnO nanocomposite as a promising option for vinasse pre-treatment and integrated agro-industrial effluent treatment. Full article

The worldwide transition to renewable energy systems is motivated by diminishing fossil fuel availability and the intensifying consequences of climate change. This study presents a Mixed-Integer Linear Programming (MILP) model for designing and optimising the bio-fuel and electricity supply chain in Colombia, using sugarcane as the main feedstock and integrating microalgae cultivation in vinasse. Six alternative biorefinery configurations and four microalgae conversion pathways were evaluated to inform strategic planning. The optimisation results indicate that microalgae achieve higher energy yields per unit of land than sugarcane. Ethanol production from sugarcane could meet all of Colombia’s gasoline demand, while diesel and sustainable aviation fuel derived from microalgae could supply around 9% and 16%, respectively, of the country’s consumption. Further-more, pelletised bagasse emerges as a viable alternative to replace part of the coal used in thermoelectric plants. From an economic perspective, all scenarios achieve a positive net present value, confirming their profitability. Sensitivity analysis highlights the critical factors influencing the deployment of distilleries as ethanol price, algae productivity, and sugarcane cost. Furthermore, transportation costs play a decisive role in the geographic location of microalgae-based facilities and the distribution of their products. Full article

The degradation of vegetation cover and the vulnerability of urban market gardening systems to climate risks are a major challenge for food security in peri-urban areas. This study analyzes the spatio-temporal dynamics of vegetation using the NDVI and assesses its correspondence with producers’ perceptions of hydroclimatic impacts. NDVIs were extracted from the MODIS MOD13Q1v6.1 product via Google Earth Engine, with a spatial resolution of 250 m × 250 m and a temporal resolution of 16 days, then processed in Python v3.14.0 using the xarray library. Additionally, 369 producers in Grand Nokoué were surveyed about the risks of flooding, drought, and heat waves, as well as the adaptation strategies they implement. The results reveal a decline in areas with a moderate to high NDVI (between 0.41 and 0.81) and an expansion of areas with a low or very low NDVI (below 0.41), reflecting increased fragmentation and degradation of vegetation cover. Producers’ perceptions confirm this vulnerability and reveal different strategies depending on the type of crop and risk, including irrigation, temporary abandonment of plots, agroforestry, and the adoption of resilient crops. These observations highlight the need to implement targeted policies and appropriate agroecological practices in order to strengthen the resilience of urban market gardening systems to extreme climate risks. Full article

Anaerobic digestion of sugarcane vinasse is integral to enhancing ethanol distilleries’ environmental and energy performance by converting organic waste into biogas; however, the flammable and toxic nature of biogas has led to significant safety concerns, particularly in anaerobic bioreactors where biogas is produced and stored. This study provides a comparative risk assessment of different anaerobic reactor configurations—a covered lagoon biodigester (CLB), a continuous stirred-tank reactor (CSTR), an upflow anaerobic sludge blanket reactor (UASB), and an anaerobic structured-bed reactor (AnSTBR)—processing vinasse, focusing on fire, explosion, and hydrogen sulfide (H₂S) toxicity hazards. Jet fire scenarios posed the most severe threat, with fatal outcomes extending up to 66 m, while the fireball scenario exhibited no lethal range. The risks to human life from explosions were minimal (1.2%). H₂S toxicity was identified as the most critical consequence, with particularly severe impacts in CLB systems, where the hazardous zone was up to 20 times larger than in AnSTBR. Therefore, the design of anaerobic bioreactors for vinasse treatment must primarily address the risks associated with H₂S-rich biogas, as reactor configuration plays a key role in mitigating or amplifying these hazards—high-rate systems such as AnSTBR and UASB demonstrating safer profiles due to their compact design and lower gas storage volumes. Full article

In this study, two native microalgae, Chlorella sp. MC18 (CH) and Scenedesmus sp. MJ23-R (SC) were cultivated in bubble column photobioreactors for wastewater treatment. Domestic wastewater (DWW) was used as the main culture medium, alone (100%) and blended (10%) with vinasse, whey, or agro-food waste (AFW), respectively. Both species thrived in 100% DWW, achieving significantly high removal efficiencies for chemical oxygen demand, total nitrogen, and total phosphorus. Mineral removal exceeded 90% in all blended systems, highlighting the strong nutrient uptake capacity of both strains. The maximum specific growth rate (µ_max) in 100% DWW was higher for SC than in standard BG11 medium, and supplementation with vinasse, whey, or AFW further increased µ_max for both species. Blending DWW significantly enhanced microalgal biomass and lipid production compared to 100% DWW. Lipid production (max., 374 mg L⁻¹), proximate lipid composition (max., 30.4%), and lipid productivity (max., 52.9 mg L⁻¹ d⁻¹) significantly increased in all supplemented cultures relative to DWW alone, demonstrating the potential of co-substrate supplementation to optimize microalgal cultivation. This study contributes to reducing the water footprint and fills a gap in the bioprocessing potential of algae-based systems, highlighting wastewater blending as a circular economy-aligned approach that supports sustainable bioprocesses and resource recovery. Full article

Brewer’s spent grain (BSG), the main lignocellulosic by-product of the beer industry, represents an abundant yet underutilized resource with high potential for valorization. This study presents an integrated biorefinery approach to convert BSG into second-generation (2G) ethanol, bioactive vinasse for plant growth promotion, and fungal biomass as a potential mycoprotein source. The biomass was first subjected to biological delignification using the white-rot fungus Ganoderma lucidum, after which two valorization routes were explored: (i) evaluation of the fungal biomass as a mycoprotein candidate and (ii) alcoholic fermentation for ethanol production. For the latter, three pretreatment strategies were assessed (diluted sulfuric acid and two deep eutectic solvents (DESs) based on choline chloride combined with either glycerol or lactic acid) followed by a one-pot enzymatic saccharification and fermentation using Kluyveromyces marxianus SLP1. The highest ethanol yield on substrate (Y_P/S) was achieved with [Ch]Cl:lactic acid pretreatment (0.46 g/g, 89.32% of theoretical). Vinasse, recovered after distillation, was characterized for organic acid content and tested on Solanum lycopersicum seed germination, showing promising biostimulant activity. Overall, this work highlights the potential of BSG as a sustainable feedstock within circular economy models, enabling the production of multiple bio-based products from a single residue. Full article

Sugarcane is a key crop for sugar, biofuels, and bioenergy, with Brazil as the world’s largest producer. Intensive cultivation demands pesticides like tebuthiuron and thiamethoxam, while fertigation with vinasse may alter their environmental behavior. Sustainable approaches, such as phytoremediation, are needed to mitigate negative impacts on soil quality. This study assessed the phytoremediation potential of Canavalia ensiformis and Mucuna pruriens in soils contaminated with tebuthiuron, thiamethoxam, and vinasse under greenhouse conditions. Experiments used a completely randomized design (five replicates, 4 × 2 factorial). Plant development impacts on the sentinel species Crotalaria juncea, and ecotoxicity via Lactuca sativa bioassays were evaluated. Tebuthiuron strongly inhibited C. ensiformis, while thiamethoxam showed mild stimulatory effects. M. pruriens maintained better growth in the presence of contaminants. Bioassays revealed greater residual toxicity in tebuthiuron treatments. Overall, M. pruriens demonstrated superior biomass production and capacity to lessen soil toxicity, underscoring its potential as a sustainable tool for phytoremediation of pesticide-impacted soils. Full article

Vinasse a byproduct of ethanol manufacturing, is a challenge for ethanol producers which possesses a high organic content that presents a considerable environmental threat. This complicates its management and treatment utilizing standard technologies like anaerobic digestion. This residue contains a substantial quantity of dead and lysed yeast cells, which can function as a protein source for livestock’s nutritional needs. The application of multi-effect evaporation enhances the characteristics of this residue by increasing protein concentration, reducing volume, and minimizing water content. This study examines the impact of the five-effect evaporation procedure on vinasse waste, focusing on its rheological properties and the concentrations of proteins, amino acids, RNA, and DNA. This study aims to assess the thermal impacts linked to the evaporation process. The findings of the one-way statistical analysis demonstrate that the five evaporation effects are relevant in the utilization of waste as feed for livestock. The substance has a viscosity of 0.933 Pa s, comprising 6.3 g/100 g of crude protein, 4.08 g/100 g of amino acids, 0.1158 g/L of DNA, and 0.1031 g/L of RNA. Full article

Wine lees is a semi-solid suspension rich in yeast cells, representing a winemaking by-product that is rarely valorized after distillation. This study focuses on the exploitation of yeast-containing vinasse resulting after wine lees distillation by proposing optimized thermal extractions that can be potentially integrated with the current wine lees distillation workflow. Vinasse with different solids concentrations (10, 30, 50%) were treated at different temperatures (104, 108, 112 °C) and durations (20, 40, 60 min) using a pressure cooker device. The release of proteins, polysaccharides, and oligosaccharides from these pressure-assisted lab extractions were compared with that in untreated vinasse and vinasse treated with a previously proposed autoclave method. The resulting extraction appears to be generally preferable to the autoclave, which would require higher costs for energy and equipment. The obtained extraction process significantly enhanced the recovery of total proteins, oligosaccharides, and medium- to low-molecular-weight polysaccharides. Conversely, all heat treatments reduced the extraction of high-molecular-weight polysaccharides, indicating that these compounds should be directly extracted from untreated vinasse. These outcomes, along with the study of samples’ viscosity, density, and specific heat, allowed us to propose an integrated extraction plant set up that includes a crossflow filter and an industrial cooker. This set up aims to maximize the extraction of each valuable fraction, thereby better exploiting vinasse following a biorefinery approach. Full article

This study pioneered an intelligent process optimization framework integrating dimensionality reduction and Box–Behnken Design response surface methodology (RSM) with MATLAB R2021b(v9.11) analytics, to advance the development of functional foods from red vinasse-blue round scad. The comprehensive nutraceutical stability assessment for key functional lipids during 4 °C storage were established by systematically evaluating microwave, boiling, and foil-baking processing. The results of intelligent processing optimization showed that the optimal parameters (red vinasse addition: 2.8 g/g; processing temperature: 4 °C; processing time: 10 h) maximized the composite quality score Y (50% texture + 50% sensory), validated by MATLAB R2021b(v9.11) to achieve near-theoretical maxima. The results of functional lipid stability showed that total fat decreased significantly (p < 0.05), with foil-baking showing the highest loss. Partial least squares regression (PLSR) analysis revealed critical degradation of nutraceutical lipids (C20:5n-3, C22:6n-3) and an increase in saturated fats (p < 0.05), where boiling induced the most severe fatty acid alterations. Microwave processing accelerated lipid oxidation (highest TBARS, p < 0.05), compromising lipid bioactivity. The framework of red vinasse biosynthesis technology enabled precise parameter optimization, and enhanced functional component retention in underutilized fish species. This work provided a theoretical and technical foundation for intelligent manufacturing of lipid-stable nutraceuticals, positioning red vinasse—a model biosynthesis technology output—as a key ingredient for next-generation functional foods. Full article

This study explored how different sugarcane vinasses influence the structure and composition of soil bacterial communities in two tropical Oxisols with contrasting textures. In a controlled microcosm experiment with sugarcane seedlings, two concentrations of three vinasse types were applied, and bacterial communities were monitored over 10, 30, and 60 days using T-RFLP and 16S rRNA gene sequencing. Across all treatments, vinasse application led to clear changes in bacterial community structure in both soils, regardless of the time point. Certain bacterial groups, such as Sphingobacteriia, Alphaproteobacteria, and Gammaproteobacteria, became more abundant—likely responding to increased carbon availability, higher pH, and greater soil moisture. At the same time, other groups declined, possibly due to excess nutrients like potassium and sulfur. Notably, these shifts occurred even when standard biochemical indicators suggested no major impact, highlighting the sensitivity of microbial community-level responses. These findings point to the importance of looking beyond traditional soil quality metrics when assessing the environmental effects of organic residue applications. Incorporating microbial indicators can offer a more nuanced understanding of how practices like vinasse reuse affect soil functioning in tropical agroecosystems. Full article

Sugarcane vinasse, a byproduct of ethanol production, presents environmental challenges due to its high organic content and occasional contamination with antibiotics, such as monensin. This study successfully evaluated thermophilic two-phase anaerobic digestion for simultaneous monensin degradation and biogas production. The system, consisting of an acidogenic anaerobic structured-bed bioreactor (ASTBR) operating at with a hydraulic retention time (HRT) of 7.5 h followed by a methanogenic reactor at HRT = 24 h, with two options of the methanogenic phase, an upflow anaerobic sludge blanket (UASB), and an ASTBR, operated continuously for 254 days with incremental monensin concentrations (0–2000 ng·mL⁻¹). The acidogenic reactor consistently removed over 70% of monensin across all phases, demonstrating its effectiveness as a pretreatment step. At realistic residual concentrations (20–100 ng·mL⁻¹), monensin not only failed to inhibit biogas production but enhanced methane yield by up to 100% through selective pressure on the microbial community. This study demonstrated that anaerobic digestion can effectively degrade monensin while increasing the value of vinasse, providing a scalable solution for mitigating antibiotic contamination and enhancing bioenergy recovery in the sugarcane–ethanol industry. Full article