Search Results (3,832)

Phenolic compounds are recognized for their antioxidant properties and potential application in sustainable functional materials. In this study, the phenolic composition and antioxidant activity of four agro-industrial residues—rice husk, spent hops, and oregano and thyme stems—were evaluated to examine the influence of the extraction method and plant matrix on bioactive compound recovery. Extracts obtained by ultrasound-assisted extraction (UAE) and conventional water bath (WB) extraction were characterized using spectrophotometric assays for total phenolic content (TPC) and antioxidant activity (DPPH and ABTS), as well as HPLC analysis for phenolic profiling. Oregano and thyme stem extracts exhibited the highest phenolic content and antioxidant activity, whereas rice husk extracts showed the lowest concentrations of detectable phenolics. Hydroxycinnamic acids, particularly p-coumaric and ferulic acids, predominated across the studied matrices. Multivariate analysis indicated that matrix composition had a greater influence on phenolic profile and antioxidant behaviour than extraction method, with UAE providing comparable results to those obtained by WB extraction while requiring a substantially shorter extraction time. Pearson correlation analysis further suggested that antioxidant activity results from the combined interaction of multiple phenolic compounds rather than isolated constituents. Overall, these residues show potential as sustainable sources of phenolic-rich extracts for functional material applications. Full article

The global wine industry generates substantial volumes of by-products, leading to significant environmental and economic challenges. This study explores the sustainable valorization of two key by-products from Moldovan red wine production—yeast lees and grape skin powder derived from autochthonous grape varieties Rară Neagră (RN) and Fetească Neagră (FN)—within the circular economy paradigm. Comprehensive physicochemical analyses demonstrated that yeast lees are a rich source of bioactive β-glucans (20.17–21.91%, w/w wet lees), proteins, and triglycerides; β-glucans of this type are reported in the literature to confer immunomodulatory and antioxidant properties, although these bioactivities were not directly evaluated in the present study. Grape skin powders exhibited high dietary fibre content and polyphenolic compounds, with FN showing superior total polyphenol content and antioxidant activity compared to RN. Advanced extraction techniques using green solvents such as glycerol, propylene glycol, and ethanol, including ultrasound-assisted methods, optimized polyphenol recovery while maintaining extract stability. Incorporation of these extracts into innovative oil-in-water cosmetic emulsions revealed notable physicochemical characteristics, with the RN extracts enhancing emulsion firmness via polyphenol–xanthan gum interactions, and the FN extracts providing high antioxidant potential without compromising texture. A preliminary single-subject biophysical assessment suggested good short-term skin compatibility, with hydration improvement and reduced transepidermal water loss in several formulations and no visible pigmentation; these observations require confirmation in a larger volunteer panel with dedicated safety testing. This work provides laboratory-scale evidence of the dual environmental and functional potential of recovering and applying Moldovan winery by-products, supporting their further development—pending pilot-scale and economic validation—as bio-ingredients for the food, cosmetic, and pharmaceutical sectors within a circular bioeconomy framework. Full article

Groundwater is a critical resource for domestic, agricultural, and industrial use in the Gilgel Gibe and Dhidhessa catchments of southwestern Ethiopia, where volcanic aquifer systems are the main sources. However, groundwater quality in these catchments has been under pressure from anthropogenic activities such as population growth, land-use changes, and pollution driven by rapid development and poor resource management. This study investigates hydrogeochemical processes and evaluates groundwater quality in volcanic aquifers using hydrochemical analyses and a stable isotope approach applied to 115 water samples. The spatial distribution of various physicochemical and hydrogeochemical parameters shows a distinct contrast between the highland and lowland regions, indicating topography-driven variations in water quality and geochemical processes. In hand-dug wells, springs, and surface waters, the ionic order is Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ and HCO₃⁻ > NO₃⁻ > Cl⁻ > SO₄²⁻, whereas deep wells show Na⁺ > Ca²⁺ > Mg²⁺ > K⁺ and HCO₃⁻ > Cl⁻ > SO₄²⁻ > NO₃⁻. The predominant groundwater type is Ca-HCO₃, followed by Na-HCO₃ and Ca-NO₃, with other types including Ca-Mg-HCO₃, Ca-Na-HCO₃, and Na-Ca-HCO₃. Water types of Ca-HCO₃ and Ca-Mg-HCO₃ dominate the upland areas, indicating relatively young groundwater with moderate total dissolved solids (TDSs) and enrichment in δ¹⁸O and δ²H, where highly mineralized Na-HCO₃ water types prevail in the deep aquifers of the lowland regions, where δ¹⁸O and δ²H are relatively depleted. Principal component analysis, cross-plots of major cations versus HCO₃⁻, and mineral stability diagrams indicate that aluminosilicate weathering and dissolution are the dominant processes controlling groundwater chemistry in the study area. The higher saturation index values observed in the deep wells indicate water closer to mineral equilibrium, suggesting more extended water–rock interaction relative to the shallow wells. The CO₂ partial pressures calculated using PHREEQC exceed atmospheric levels (~10^−3.5 atm), indicating sources from atmospheric influx, soil, or biogenic activity for most samples, and deeper sources such as mantle degassing may be found in a few deep wells. Scatter plots of Cl⁻ vs. SO₄²⁻ and Cl⁻ vs. NO₃⁻, associated with Ca(NO3)₂, NaNO₃, and CaCl₂ water types, suggest that anthropogenic inputs are the second major factor influencing the area’s water chemistry. Stable isotope analyses and hydrochemical data indicate that groundwater in the area primarily originates from local precipitation, with isotopic signatures reflecting strong groundwater–surface water interaction. These findings improve understanding of regional hydrogeochemistry and groundwater quality and help identify promising zones for sustainable groundwater development. This study provides valuable insights into groundwater resource management both in the study area and in regions sharing comparable geological contexts. Full article

The valorisation of industrial by-products as supplementary cementitious materials is a promising strategy to reduce clinker consumption and improve the sustainability of cement-based materials. In this study, the influence of submerged arc welding (SAW) slag on the hydration behaviour and microstructural evolution of cement pastes was investigated. Two SAW slags from different industrial sources were incorporated as partial replacements of ordinary Portland cement at 5%, 15%, and 30% by mass. Cement pastes were prepared with water-to-binder ratios of 0.3 and 0.4 and characterised through setting time, water demand, mercury intrusion porosimetry (MIP), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The results showed that SAW slag systematically delayed both initial and final setting times, while having only a negligible effect on water demand. Under the fixed mix conditions adopted in this study, this retardation is interpreted as the combined effect of clinker dilution and modified fresh-state conditions. MIP analysis revealed higher early-age porosity in SAW-containing pastes, particularly at high replacement levels and higher water-to-binder ratios, although mixtures with up to 15% slag approached the reference pore structure at later ages. Thermal analysis indicated lower bound water and portlandite contents at early ages, mainly due to clinker dilution, while long-term hydration development remained comparable at moderate replacement levels. At higher slag contents, some mixtures showed higher calcium carbonate contents, suggesting a tendency toward increased carbonate formation under the investigated conditions. Overall, the results indicate that SAW slag primarily affected early paste behaviour and pore structure development, with clinker dilution appearing to be the main mechanism, although weak secondary physical or chemical contributions cannot be completely excluded. Full article

Microbially induced calcium carbonate precipitation (MICP) is a promising biotechnology for environmental remediation; however, the high cost of conventional chemical-grade calcium sources limits its large-scale scalability. This study evaluated the feasibility of utilizing an aqueous extract of natural attapulgite clay as a sustainable, low-cost calcium source for MICP-mediated arsenic (As) immobilization in both aqueous and soil systems. Among the tested minerals, Baiyin attapulgite (group B) exhibited the highest calcium content (62,808.94 mg kg⁻¹) and minimal toxic metal impurities, providing a favorable chemical matrix for biomineralization. At an optimal solid-to-liquid ratio of 1:10, Lysinibacillus fusiformis LF and Enterococcus LZU-1 successfully induced calcite precipitation driven by the attapulgite extract. In batch aqueous remediation experiments (20 days), the attapulgite extract significantly enhanced As removal efficiency compared to the controls; As removal rates peaked at 66.4% for strain LZU-1 (with LZ1 extract) and 65.8% for strain LF (with group B extract), drastically outperforming the standard CaCl₂ groups (31.2–37.3%) and blank controls (21.8–24.5%). Concurrently, soil incubation experiments (30 days) demonstrated that the combined application of attapulgite and MICP bacteria reduced the highly bioavailable exchangeable As fraction from 0.115 to approximately 0.03 mg kg⁻¹, while effectively driving its transformation into more stable carbonate-bound and organic-bound fractions without causing secondary soil salinization. Morphological and mechanistic analyses revealed that, compared to the well-defined euhedral crystals in the CaCl₂ control, the precipitates mediated by the clay extract exhibited distinctly irregular, defect-rich rhombohedral structures. This structural disruption was governed by the natural matrix effect of attapulgite, which simultaneously supplied dissolved Ca²⁺ and provided an abundance of fine clay fragments, calcite micro-grains, and associated amorphous Fe/Al/Mn-bearing phases. These constituents acted as physical scaffolding and heterogeneous nucleation sites that became embedded in the growing CaCO₃ lattice, driving the formation of highly reactive, defect-rich clay-calcite-arsenic composite precipitates that efficiently encapsulated arsenate. Mantel analysis further revealed that the remediation efficiency was significantly correlated with key environmental variables including Ni, V, Ca. These findings highlight the dual-system potential of natural attapulgite as an inexpensive, eco-friendly calcium alternative for sustainable MICP-based remediation of As-contaminated water and agricultural soils. Full article

The Huaibei region is a critical grain and energy–chemical base in northern China, characterized by substantial water demand for industrial and agricultural production. Karst groundwater systems constitute the primary water supply source in this area. Under the superimposed impacts of intensive exploitation, climate change, and anthropogenic activities, karst aquifers have encountered a series of geo-environmental problems, including groundwater level decline and expansion of cones of depression. Most previous studies have predominantly focused on water quality assessment and groundwater resource quantification, yet systematic investigations into the multi-scale characteristics and driving mechanisms of karst groundwater level dynamics remain insufficient. In this study, based on long-term groundwater level and rainfall monitoring data (2014–2024) from three monitoring wells representing different types of karst aquifers, continuous wavelet transform (CWT) and wavelet coherence (WTC) approaches are introduced to identify the periodic patterns of karst groundwater levels and reveal the dominant controlling factors of groundwater level dynamics. The results demonstrate that groundwater levels in all types of karst aquifers exhibit distinct multi-scale periodic variations. The groundwater levels of HB01 and HB02 share dominant oscillation periods of 18~19 months and 9 months with regional rainfall, while the groundwater level at HB03 displays a more complex, multi-scale, periodic combination of 41 months, 18~19 months, and 9 months. Periodic variations in regional rainfall serve as the dominant controlling factor for the intra-annual and inter-annual periodic fluctuations of karst water levels, with a prominent resonance relationship identified between the two variables at dominant periodic scales. Distinct heterogeneity is observed in the response magnitude and lag time of different karst aquifer types to rainfall; specifically, the lag time of water level response to rainfall on the annual periodic scale ranges from 2.7 to 2.9 months. The correlation between annual average water level and pumping discharge is moderate for boreholes HB01 and HB03, whereas a strong correlation is detected for borehole HB02, implying that its water level regime is likely subjected to pronounced pumping disturbance. The degree of karst development, aquifer burial depth, and overlying stratum architecture are the key geological factors accounting for such heterogeneous response patterns. For the first time, this study utilizes long-term water level time series data from the karst water exploitation zone of the Huaibei Plain, complemented by synchronous precipitation and pumping records. Integrated with regional hydrogeological settings, wavelet analysis is employed to conduct an in-depth investigation into the dynamic variations in karst water levels in the Huaibei region from the perspective of groundwater recharge–discharge relationships. The results provide a scientific underpinning for the remediation of karst water over-exploitation and the optimal allocation of water resources. Specifically, pumping and artificial recharge schemes can be proactively adjusted based on periodicity forecasts. Zoned management strategies for water resources are put forward: artificial regulation and storage are recommended for zones with sensitive hydrological responses, while preventive protection is prioritized for zones with sluggish responses. By incorporating periodic characteristics and lag durations, targeted pumping strategies for dry and wet seasons can be developed, and a coupled water level–rainfall–pumping early warning system can be established to realize the long-term sustainable regulation of karst water resources. Full article

Global climate change is intensifying water scarcity in Mediterranean agroecosystems, demanding a transition from rainfed to irrigated management for high-value crops like vineyards and olive groves. This study introduces a novel hydrologic framework to assess field-scale rainwater harvesting potential across nearly 60,000 individual vineyard and olive grove parcels in continental Portugal. Unlike conventional valley-focused models that delineate catchments at drainage junctions, our approach uses high-resolution digital elevation models and open-source spatial libraries (Python’s Fiona, Rasterio, Whitebox) to link every agricultural pixel to its unique upstream hillslope catchment. We quantify and compare “in-parcel” resources (direct precipitation, Vp) with “ex-parcel” resources (upstream runoff, Vup) under historical (1981–2010) and future (2041–2070) climate scenarios (CMIP6; SSP1-2.6, SSP3-7.0, and SSP5-8.5). A central contribution of this study is the evaluation of water security, defined here as the relative safety buffer between harvested water and the biological irrigation requirements (Vip) prescribed for both cultures in each of seven agroclimatic zones defined across the country. Security categories are based on the ratio (Vp − Vip)/Vip for in-parcel resources and (Vup − Vip)/Vip for ex-parcel resources, where values above zero indicate a sustainable surplus, and negative values signify a state of insecurity. Results demonstrate that ex-parcel resources are significantly more substantial, offering 2.5 to 35 times the potential of in-parcel counterparts. While vineyards currently exhibit high security nationwide, southern olive groves face a critical degradation from “secure” to “insecure” status by 2070 under fossil-fueled pathways (SSP5-8.5), with security indices dropping as low as −33.2 in the southern Alentejo region. This highlights ex-parcel runoff as a vital, underutilized hydrologic buffer that can safeguard Mediterranean agriculture against projected climate-induced deficits. Full article

The objective of this study was to determine the energy balance and greenhouse gas (GHG) emissions associated with the production of industrial hemp (Cannabis sativa L.) under semi-arid Central Anatolian conditions. A field experiment was conducted using the registered industrial hemp cultivar ‘Vezir’ under semi-arid conditions, and energy use indicators and greenhouse gas emissions were quantified through an input–output analysis based on field-level agricultural inputs and biomass yield. The total energy input was calculated as 13,688.50 MJ ha^–1, of which chemical fertilizers (54.339%) and diesel fuel (32.09%) jointly accounted for more than 90%, followed by irrigation water (4.66%), machinery 2.87%), and human labor (0.21%). The corresponding energy output reached 388,073.80 MJ ha^–1, yielding an energy use efficiency of 28.35, a specific energy of 0.62 MJ kg^–1, an energy productivity of 1.61 kg MJ^–1 and a net energy of 374,385.28 MJ ha^–1. Of the total energy input, 36.95% was direct and 63.05% indirect, while 89.35% originated from non-renewable sources and only 10.65% originated from renewable sources. Total GHG emissions amounted to 590.14 kg CO₂ eq ha^–1, with diesel fuel and nitrogen fertilizer identified as the dominant emission sources. These findings indicate that industrial hemp combines high productivity with low environmental burdens under semi-arid conditions. Beyond its favorable energy balance, hemp offers potential contributions to climate-smart agriculture through efficient resource use, reduced greenhouse gas emissions per unit of output, and diversification of cropping systems in water-limited environments. Therefore, industrial hemp can support the transition toward more sustainable and resilient agricultural systems in semi-arid regions of Türkiye and similar agroecological zones. Full article

Lake Baikal is a UNESCO World Heritage Site and the largest freshwater reservoir on the planet. It is located in the center of Eurasia, in an industrially developing region—Eastern Siberia. Although a regulatory and legal framework exists, quantitative estimates of the pathways of pollutant transport from industrial sources to the lake water area remain insufficiently studied, particularly in the context of seasonal dynamics and the influence of developing industrial sectors. In the present work, a quantitative analysis of the direct atmospheric transport of pollutants from three groups of stationary sources (the Irkutsk agglomeration, the Republic of Buryatia, and the oil-and-gas production areas of Irkutsk Oblast) to the lake surface was carried out for the first time using the HYSPLIT model for the period 2005–2025. About 4.7 million forward trajectories were computed at three heights (250, 500, 1000 m AGL) for each group of sources. It was established that conditions favorable for the transport of impurities to the lake occur in more than half of the cases. However, the spatial distribution of the impact on the Baikal air basin is heterogeneous: the Irkutsk agglomeration accounts for 67.5% of the “hits” (the main contribution being to the air basin of the Southern Basin), the Republic of Buryatia 18.8% (to the Central Basin), and the oil-and-gas areas 19.9% (to the Northern Basin). On the basis of a multifactor analysis, a combined Potential Impact (PI) index was developed that makes it possible to rank regional sources by the degree of their impact on the lake ecosystem, taking into account the emission volume, the probability of delivery, the residence time, and the height of trajectory passage. The results form a scientific basis for optimizing the spatial placement of environmental monitoring networks and for preliminary zoning of environmental risk assessment over the Lake Baikal water area. Ultimately, this study contributes to the sustainable management of the Baikal Natural Territory by providing actionable insights for balancing regional industrial growth with the long-term ecological preservation of the planet’s largest freshwater reservoir. Full article

This study investigated nitrate contamination, potential nitrate sources, and transformation processes in shallow and deep groundwater of a steep coastal agricultural catchment in western Japan. Hydrochemistry and Endmember Mixing Analysis (EMMA) were applied to shallow and deep groundwater samples collected along a groundwater flow path. A spring and a river sample were used for comparative purposes. The results suggested that the groundwater hydrochemistry comprised mixed, Ca-HCO₃, Ca-Cl, and Na-Cl water types. Nitrate concentrations exceeded 10 mg L⁻¹ in 51.1% (23 out of 45) of the groundwater samples, higher in upstream groundwater than downstream groundwater, especially in deep wells. EMMA suggested agricultural recharge water as potentially the main nitrate source contributor to groundwater. Sewage contributions were greater in shallow wells, and deep natural groundwater in deep wells. The transformation processes were associated with nitrate addition via fertilizers and nitrification, water mixing, and nitrate removal potential by denitrification in shallow downstream wells. Sewage contributions were associated with the shallow downstream groundwater in areas with a greater residential area. Groundwater mixing was suggested to influence hydrochemical variability, especially in DD groundwater, which showed stronger coastal influences. These findings improve understanding of nitrate contamination and support sustainable groundwater management in steep coastal agricultural areas. Full article

Resilience and adaptation to extreme climate events have become an urgent necessity. As cities grow denser, increasing numbers of people are exposed to water scarcity, flooding, and power grid disruptions. Immediate action is required to safeguard human lives and property. Residential buildings exert a significant environmental impact throughout their operational phase, contributing to air, land, and water pollution. A more sustainable and proactive approach to building management is essential to reduce the consumption, processing, and disposal of natural resources. This article explores the potential for biogas production from decentralised/on-site wastewater treatment systems through the co-digestion of blackwater (BW) and kitchen waste (KW) for existing residential buildings located in densely populated urban areas using hybrid grids. It addresses the importance of wastewater source separation, the use of BW and KW blends to achieve the best biogas production, and the environmental, economic and social aspects of these systems’ implementation. An extensive literature review and state-of-the-art analysis were conducted to assess the potential, main challenges, and research directions in this field. The results indicate that decentralised anaerobic systems can be technically feasible, reducing grid energy dependence, optimising water use, and valorising digestate as fertiliser—fully aligned with the EU’s Green Deal and the UN Sustainable Development Goals regarding sustainability and circularity. However, few studies address the feasibility of BW (vacuum toilet) and KW co-digestion for combined heat and power generation in hybrid grids. Further pilot- and full-scale research is therefore needed to increase system reliability and social acceptance. Full article

Urban drainage overflows can release a large fraction of event-scale pollutants during the early stage, yet current control remains largely driven by hydraulic signals rather than pollutant-release dynamics. This study created a dissolved organic matter (DOM)-based fluorescence fingerprint method to precisely identify the shift from pollutant flushing to dilution or ongoing input, helping determine the timing of first-flush transitions and potential interception. Fourteen wet-weather overflow events from seven drainage systems in Shanghai and Changzhou were investigated using excitation–emission matrix fluorescence spectroscopy, combined with non-negative matrix factorization, random forest feature screening, principal component analysis, mass–volume (M(V)) curve analysis, and Pettitt change-point detection. Five macro-scale fluorescence fingerprints were resolved, representing protein-like, fulvic-like, and humic-like components. Protein-like fingerprints dominated rapid event-scale variations, while fulvic-like and humic-like fingerprints reflected continuous surface-derived input and stable background contribution, respectively. Peak-shift trajectories revealed three fluorescence-evolution modes: directional red-shift migration, peak-position stability, and weak, non-directional variability, reflecting different source-release dynamics and DOM compositional adjustments during overflow. Random forest screening identified 20 high-importance fine-scale fluorescence fingerprints, with 90% concentrated in protein-like regions linked to sewage-derived and labile DOM. Compared with macro-scale fingerprints and conventional water quality indicators, fine-scale fluorescence fingerprints showed clearer stage separation, stronger consistency with M(V)-based cumulative response patterns, and more distinct first-flush interception timing. This timing marked the transition from early concentrated pollutant release to dilution or sustained input, whereas macro-scale fingerprints indicated broader transition intervals and conventional indicators showed delayed responses. These findings highlight the potential of fine-scale fluorescence fingerprints to support future fluorescence-assisted overflow control by improving transition identification and targeted interception decisions. Full article

The textile industry is one of the largest consumers of synthetic dyes and a significant source of industrial wastewater contamination. More than 7 × 10⁵ tons of synthetic dyes are produced annually worldwide, and it is estimated that 10–15% of these dyes are released into industrial effluents during manufacturing and textile processing, contributing significantly to aquatic contamination. Due to their complex aromatic structures, many synthetic dyes exhibit high chemical stability and resistance to conventional wastewater treatment processes, leading to persistent environmental pollution. This review discusses the main classes of synthetic dyes used in the textile industry, focusing on their chemical classification, environmental impacts, and associated ecological risks. Dye categories are analyzed both according to their application to textile fibers and their molecular structure, highlighting how these characteristics influence their persistence and toxicity in aquatic environments. Unlike previous reviews that primarily emphasize individual treatment technologies, this work provides an integrated perspective linking dye chemistry, environmental behavior, and the mechanisms, advantages, and limitations of physical, chemical, and biological remediation strategies. The environmental impacts of dye-contaminated effluents include reduced light penetration in water bodies, disruption of aquatic ecosystems, and potential toxic and mutagenic effects on living organisms. In addition, the review examines current remediation strategies for dye removal from textile wastewater, including physical, chemical, and biological treatment methods. Particular attention is given to biological degradation, as well as hybrid systems that combine multiple technologies to improve treatment efficiency. Finally, the advantages, limitations, and future perspectives of these remediation strategies are discussed, emphasizing the need for sustainable and efficient approaches to mitigate the environmental impacts of textile dye pollution. Full article

The world is facing a triple global crisis: climate change, loss of biodiversity, and pollution. Plastics, man-made polymers from primary fossil fuel sources, have pervasively entered almost every sector and thereby caused huge environmental pollution. Microplastic (MPs) sizes range between 1 μm and 5 μm, and nanoplastics are less than 1 μm in size, respectively. Behaviour, accumulation and movement of plastics in soil, water and air depend on their size. Smaller sizes of microplastics and nannoplastics can easily enter cells, tissues, and finally, the food chain, and pose growing ecological and health concerns due to their persistence. It also acts as an adsorbent and has the ability to penetrate food webs. Their diverse shapes, especially fibres, increase their dispersal and bioavailability in aquatic ecosystems. Recent findings indicate that microalgae contribute to the mitigation of microplastic pollution. Microalgae, diverse photosynthetic microorganisms ranging from 0.5 to 200 μm, interact with microplastics through processes such as adsorption, aggregation, and potential biodegradation mechanisms, including toxin systems or enzymes produced by the microalgae, utilising plastic polymers as carbon sources. The filamentous morphology of some species, such as Spirulina sp., increases the entrapment and potential degradation of microplastic fibres. It is essential to understand these interactions to construct sustainable means of mitigating microplastic pollution and recovering the aquatic ecosystem health. Microalgae produce enzymes such as lipases, esterases, and cellulases, which facilitate the biodegradation of plastics. Microalgae form biofilm on the surface of microplastics. They also secrete sticky extracellular polymeric substances (EPS) that cause the microplastic to sink to the bottom of the water body, which helps to remove microplastics from surfaces. This review summarises knowledge on microalgae–microplastic interactions, with a focus on their potential for bioremediation of microplastics and also sustainable conservation of the environment. Full article

Germinated Andean lupin whole flour (GAL) is rich in protein, dietary fiber, essential amino acids, and bioactive compounds, representing a promising alternative for the development of sustainable plant-based foods. This study investigated the feasibility of partially replacing soy protein isolate (SPI) with GAL in high-moisture extruded meat analogues. A central composite design was applied to evaluate the effects of the GAL ratio (0:100–50:50) and feed moisture content (50–70%) on the technological properties of the extrudates. The Response Surface Methodology was used to model and optimize the process. The incorporation of GAL significantly affected the (p < 0.10) water solubility index (WSI), oil absorption capacity (OAC), cooking loss (CL), yellowness (b*), cohesiveness, and adhesiveness, generating predictive models with satisfactory goodness-of-fit (R² > 0.75). Increasing GAL levels increased the WSI from 6.21 to 18.79% and cooking loss from 1.01 to 3.84%, while reducing OAC from 239.42 to 166.57%, indicating substantial modifications in matrix organization and hydration behavior. Numerical optimization identified an optimal formulation containing 12% GAL, 88% SPI, and 65.5% feed moisture, with a desirability of 77.82%. Model validation showed relative deviations lower than 10% between predicted and experimental values. The optimized meat analogue exhibited high protein content (84.44%), favorable techno-functional properties, and improved nutritional quality, with higher levels of branched-chain amino acids (17.34 g·100 g⁻¹ protein), essential amino acids (33.32 g·100 g⁻¹ protein), and in vitro protein digestibility (90.1%) compared with the control formulation. Multivariate analyses confirmed that phenylalanine, histidine, methionine, and leucine were the main variables that discriminated between the protein sources and the extruded products. Overall, GAL demonstrated strong potential as a sustainable functional ingredient to produce nutritionally enhanced high-moisture meat analogues. Full article