Search Results (1,384)

Chromium-doped hydroxyapatite (7CrHAp) and chromium-doped hydroxyapatite in chitosan matrix (7CrHAp-CH) coatings were synthesized in order to address the need for biomaterials with improved physico-chemical and biological properties for biomedical applications. Both chromium-doped hydroxyapatite (7CrHAp) and chromium-doped hydroxyapatite in chitosan matrix (7CrHAp-CH) coatings could represent promising materials for biomedical applications due to their superior properties. This study aims to evaluate the physico-chemical and in vitro biological properties of 7CrHAp and 7CrHAp-CH coatings to determine the impact of chitosan incorporation on the physico-chemical and biological features. The results reported in this study indicate that addition of chitosan improves surface uniformity and biological properties, highlighting their potential for uses in biomedical applications. In this study, coatings of chromium-doped hydroxyapatite (7CrHAp, with x_Cr = 0.07) and its composite variant embedded in a chitosan matrix (7CrHAp-CH) were systematically analyzed using a suite of characterization techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and metallographic microscopy (MM). The results of the XRD analysis revealed that the average crystal size was 19.63 nm for 7CrHAp and 16.29 nm for 7CrHAp-CH, indicating a decrease in crystallite size upon CH incorporation. The films were synthesized via the dip coating method using stable suspensions, whose stability was assessed through ultrasonic measurements (double-distilled water serving as the reference medium). The values obtained for the stability parameter were 2.59·10⁻⁶ s⁻¹ for 7CrHAp, 8.64·10⁻⁷ s⁻¹ for 7CrHAp-CH, and 3.14·10⁻⁷ s⁻¹ for chitosan (CH). These data underline that all samples are stable: CH is extremely stable, followed by 7CrHAp-CH (very stable) and 7CrHAp (stable). The in vitro biocompatibility of the 7CrHAp and 7CrHAp-CH coatings was evaluated with the aid of the MG63 cell line. The cytotoxic potential of these coatings towards MG63 cells was quantified using the MTT assay after 24 and 48 h of incubation. Our results highlight that both 7CrHAp and 7CrHAp-CH coatings exhibit high biocompatibility with MG63 cells, maintaining cell viability above 90% at both incubation times, thus supporting osteoblast-like cell proliferation. Furthermore, the antimicrobial efficacy of both 7CrHAp and 7CrHAp-CH samples was evaluated in vitro against the Pseudomonas aeruginosa 27853 ATCC (P. aeruginosa) reference strain. The in vitro antibacterial activity of the 7CrHAp and 7CrHAp-CH coatings was further evaluated against Pseudomonas aeruginosa 27853 ATCC (P. aeruginosa), Escherichia coli ATCC 25922 (E. coli) and Staphylococcus aureus ATCC 25923 (S. aureus) reference strains. In addition, atomic force microscopy (AFM) analysis was also used to investigate the ability of P. aeruginosa, E. coli and S. aureus cells to adhere and to develop colonies on the surfaces of the 7CrHAp and 7CrHAp-CH coatings. The results from the biological assays indicate that both coatings exhibit promising antibacterial properties, highlighting their potential for being used in biomedical applications, particularly in the development of novel antimicrobial devices. Full article

The present study aimed to comprehensively characterize the physicochemical, nutritional, and functional properties of Armoracia rusticana leaves and roots, with a focus on their potential as sources of bioactive compounds. Quality parameters (color, moisture, titratable acidity, pH), macronutrient (proteins, fats, carbohydrates, fibers) and micronutrient (minerals, vitamins) content were determined. Polyphenolic profiles were evaluated using HPLC-DAD in two types of extracts: methanol–water (1:1, v/v) and deionized water. Flavonols (quercetin, kaempferol, myricetin), hydroxybenzoic acids (p-hydroxybenzoic, vanillic, caffeic), and hydroxycinnamic acids (chlorogenic, p-coumaric, rosmarinic) were identified. Freeze-drying proved effective in preserving thermolabile compounds, such as vitamin C (299.78 mg/100 g) and polyphenols (107.14 mg/100 g). Antioxidant capacity of the leaf extracts ranged between 74.52% and 76.90%, while pigment quantification revealed high levels of chlorophyll a (360.7 mg/100 g), chlorophyll b (110.03 mg/100 g), and total carotenoids (72.35 mg/100 g). FTIR spectroscopy was employed to assess molecular structures and functional group composition. Overall, the results support the valorization of A. rusticana leaves—an underutilized plant part—alongside roots, for applications in functional foods and nutraceutical development. Full article

The bioactive properties of a phenolic extract (PE) obtained from olive mill vegetation water (OVW) in powder formulation were utilized to enrich a meat analog composed of lentils and champignon mushrooms. The primary phenolic compounds in this extract were oleacein, verbascoside, and hydroxytyrosol. The effects on the final product were assessed over eight days of storage at 4 °C ± 2 under 12 h of light. The control samples were compared with two meat analogs enriched with ascorbic acid (AA) at 5 g kg⁻¹ and one enriched with PE at 30 g kg⁻¹. The physicochemical parameters (pH, aw, color, texture, and total phenol content), antioxidant activity, microbial assessment, and sensory evaluations of meat analog samples were evaluated at three different time points (T0, T4, T8) during shelf life. The PE-enriched meat analogs maintained a relatively high and stable phenolic concentration throughout their shelf life, significantly enhancing the antioxidant activities of the final product. The addition of PE also influenced the growth of Enterococcus spp., Lactococcus spp., and Lactobacillus spp. during storage. The results of the triangular test indicated perceptible differences between AA and PE meat analogs. Meanwhile, the quantitative descriptive analysis (QDA) emphasized notable enhancements in odor and texture characteristics for PE-enriched samples. Plant-based meat analogs can benefit from the effective use of PE (antioxidant and sensory properties), supporting the sustainable reuse of olive oil by-products. Full article

Water quality management is crucial for sustainable whiteleg shrimp (Litopenaeus vannamei) aquaculture, though little research has comprehensively investigated the spatiotemporal fluctuation of trace elements in tropical semi-intensive ponds. This study investigated the water quality variations and trace element concentrations in an earthen pond across a 56-day culture cycle during the dry season. Physicochemical parameters (temperature, pH, salinity, dissolved oxygen, ammonia, nitrite, and nitrate) and trace elements (Cu, Zn, Mn, Fe, and Mg) were measured concurrently with shrimp growth and survival. The DO and pH readings were observed to fluctuate significantly during the mid-to-late stages of culture, with DO nearing critical thresholds (<5.0 mg L⁻¹). A sudden increase in ammonia and nitrite levels suggested the accumulation of organic matter and a microbial imbalance. Zinc concentrations (0.28–1.00 mg L⁻¹) approached stress-inducing levels, while magnesium remained low (10.44–10.72 mg L⁻¹). Pearson’s correlation revealed strong positive associations between ammonia and nitrate (r = 0.95) and between DO and pH (r = 0.94), while Mg was negatively correlated with Fe (r = −0.99) and nitrite (r = −0.88). Shrimp achieved 13.43 ± 0.73 g mean weight, with 77.8% survival and an FCR of 1.08. These results provide baseline evidence that combined water quality and trace element monitoring can become an early warning framework for pond management. Future studies integrating shrimp physiology and immune responses are needed to establish direct causal relationships. Full article

Water treatment systems in swimming ponds support the natural self-cleaning capabilities of water based on the functions of repository macrophytes in their regeneration zone and the regulation of the internal metabolism of the reservoirs. As part of the project, a functional modular filtration chamber with system multiplication capabilities was designed and created. This element is dedicated to water treatment systems in natural swimming ponds. The prototype system consisted of modular filtration chambers and pump sections, as well as equipment adapted to the conditions prevailing in the eco-pool. An innovative solution for selective shutdown of the filtration chamber without closing the circulation circuit was also used, which forms the basis of a patent application. A verified high-performance adsorbent, Rockfos^® modified limestone, was used in the filtration chamber. In order to determine the effective filtration rate for three small test ponds with different flow rates (5 m/h, 10 m/h and 15 m/h), the selected physicochemical parameters of water (temperature, pH, electrolytical conductivity, oxygen saturation, total hardness, nitrites, nitrates, and total phosphorus, including adsorption efficiency and bed absorption capacity) were researched before and after filtration. Tests were also carried out on the composition of fecal bacteria and phyto- and zooplankton. Based on high effective phosphorus filtration efficiency of 32.65% during the operation of the bed, the following were determined: no exceedances of the standards for the tested parameters in relation to the German standards for eco-pools (FLL—Forschungsgesellschaft Landschaftsentwicklung Landschaftsbau e. V., 2011); lower number of fecal pathogens (on average 393—coliform bacteria; 74—Escherichia coli; 34—fecal enterococci, most probably number/100 mL); the lowest share of problematic cyanobacteria in phytoplankton (<250,000 individuals/dm³ in number and <0.05 µg/dm³—biomass); low chlorophyll a content (2.2 µg/dm³—oligotrophy) and the presence of more favorable smaller forms of zooplankton, an effective filtration speed of 5 m/h. This velocity was recommended in the FLL standards for swimming ponds, which were adopted in this study as a reference for rapid filters. In testing the functional efficiency of a dedicated filtration system for a Type II test pond (50 m²—area and 33 m³—capacity), at a filtration rate of 5 m/h, an average effective phosphorus adsorption efficiency of 18.28–53.98% was observed under the bed work-in-progress conditions. Analyses of other physicochemical water parameters, with appropriate calculations and statistical tests, indicated progressive functional efficiency of the system under bathing conditions. Full article

This present study aimed to investigate the recovery of polyphenols from red onion peel (OPP) and pomace of Merlot (MWP) and Syrah (SWP) grape varieties, using a common biphasic solvent (70/30 ethanol/water) and a new biphasic and eco-friendly solvent that has been developed in our laboratory (ethanol of grape origin). Moreover, overnight and ultrasonic-assisted extractions were carried out to investigate whether the extraction method could affect the obtained results. Results showed that 70% ethanol achieved a significantly (p < 0.05) higher yield in total phenolic content (TPC) and total flavonoid content (TFC), while the extracts with ethanol of grape origin exhibited considerably higher antioxidant activity as evidenced by the DPPH and complementary by FRAP assays. The overnight and ultrasonic-assisted extraction played a significant (p < 0.05) role in achieving better extraction of bioactive components such as phenolic compounds. Color parameters were also determined, showing that the presence of yellow, blue and red color tones depend on the extraction method and solvent, due to the different compositional characteristics of pigments, mainly anthocyanins. In addition, physicochemical parameters such as pH and total soluble solids (TSSs) of the extracts were also measured. Finally, the composition of ethanol of grape origin was characterized by means of Ultraviolet–Visible (UV-Vis) and Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, which confirmed the presence of ethanol and acetic acid. This study brings new results regarding the prospect of using new solvents for the recovery of bioactive compounds from agricultural by-products, and the development direction of scientific research or industrial production, based on ultrasonic-assisted and overnight extraction methods. Full article

The galvanic industry requires considerable amounts of water and produces significant quantities of wastewater. Two types of wastewater are created in the processes of the galvanic application of metal coatings: used galvanic baths and wastewater generated while rinsing coated elements. The composition and amount of wastewater depend on the type of process, the plant’s operational system, and the quantity of water utilised to rinse the coated elements. In this article, the possibilities of using different techniques, such as chemical precipitation, coagulation and flocculation, ion exchange, adsorption, and membrane filtration, to remove heavy metals from galvanic wastewater were analysed and assessed. It was determined that the use of physicochemical methods (i.e., chemical precipitation, coagulation, and flocculation) to remove heavy metals has significant disadvantages, including operational costs connected with the purchase of chemical reagents and the emergence of metal complexes requiring management/utilisation. On the other hand, the processes of ion exchange and adsorption can be used only for wastewater characterised by a low heavy metal concentration, with organic matter preliminarily removed. In addition, waste polluted with heavy metals in the form of used regenerative baths and used sorbents is generated during these processes. In turn, the advanced techniques of membrane filtration allow for the removal of different types of organic pollutants and heavy metals. The processes of membrane wastewater treatment exhibit a range of advantages compared to traditional technologies, including the complete, environmentally friendly removal of permanent organic pollution, easy integration into conventional technologies, a limited amount of residue, a high level of separation, and a shorter process time. The efficiency of membrane wastewater treatment depends on many parameters, including, most of all, the composition, pH, and type of membrane, as well as process conditions. The possibility of using new types of membranes to remove heavy metals from spent galvanic baths was analysed, and the possibility of using the processes in wastewater treatment systems according to the circular economy model was assessed. The assessment of the efficiency of heavy metal removal in hybrid systems combining specific individual processes and the development of state-of-the-art material solutions to realise these processes may be an interesting direction of research in this field. Full article

The continuous increase in urbanization and global population has led to the generation of a substantial amount of kitchen waste, posing severe environmental and disposal challenges. The utilization of kitchen waste as organic biomass for biochar production offers a promising, sustainable, and cost-effective solution. This review comprehensively analyzes the recent developments in the transformation of kitchen waste into biochar. Moreover, the current study involves various synthesis techniques, the physicochemical characteristics of biochar, and its applications in soil and water remediation. Afterwards, the experimental parameters and feedstock types are critically evaluated in terms of their key characteristics for biochar. Moreover, the current study highlights the effectiveness of kitchen waste-derived biochar (KWBC) in decomposing organic pollutants, heavy metals, and pharmaceutical pollutants from contaminated environments. Additionally, the mechanisms of adsorption, ion exchange, complexation, and redox interactions are thoroughly illustrated to evaluate the pollutant removal pathways. At the end of the study, experimental parameters such as pH, dosage, contact time, and initial pollutant concentration are discussed, which play the main role in enhancing the adsorption capacity of biochar. Finally, this review outlines current limitations and proposes future directions for optimizing biochar performance and promoting its large-scale application in sustainable environmental management. Full article

Bio-based nanofibers are gaining increasing attention in nanotechnology owing to their high surface area, interconnected porosity, and capacity to incorporate bioactive compounds. Among natural polymers, gelatin is particularly attractive because of its abundance, low cost, biodegradability, and versatile physicochemical properties. When processed by electrospinning, gelatin combines its amphiphilic nature with the structural advantages of nanofibers, enabling efficient interactions with a wide range of molecules. Nevertheless, pure gelatin nanofibers have drawbacks, such as poor mechanical strength and high-water solubility. To address these limitations, strategies including polymer blending, chemical and physical crosslinking, and multilayer biomaterials have been developed, resulting in improved stability, functionality, and application-specific performance. Therefore, this review summarizes recent advances in the fabrication and functionalization of gelatin nanofibers, highlighting how processing parameters and gelatin source influence electrospinning outcomes and fiber properties. Key applications are also discussed, with emphasis on biomedical, food, environmental, and biosensing. Therefore, gelatin nanofibers represent a sustainable and versatile biomaterial with high potential for advanced technological applications. Full article

Water quality in Peru is an increasing concern, particularly in the upper Huarmey watershed, which is affected by heavy metal contamination and untreated wastewater. This study proposes an automated classification approach using three supervised machine learning algorithms—K-Nearest Neighbors (KNN), Support Vector Machine (SVM), and Random Forest (RF)—to assess the water quality based on the Water Quality Index (WQI) of Peru. The experimental results show that KNN outperforms other methods, reaching an accuracy of 95.2%. The proposed system automates and improves the classification accuracy compared with manual methods based on Microsoft Excel. The methodology, performance metrics, dataset characteristics, and geographical context are detailed to ensure replicability. This algorithm assists decision-makers with environmental monitoring and public health protection. Full article

Bacterial cellulose (BC) is a high-purity biopolymer with excellent physicochemical and mechanical properties, including high crystallinity, water absorption, biocompatibility, and structural tunability. However, its large-scale production is hindered by high substrate costs and limited sustainability. In this study, spent black tea waste was utilized as a low-cost and eco-friendly carbon source for BC synthesis by Komagataeibacter xylinus ATCC 53524 under varying initial pH conditions (4–9). Six different BC membranes were produced and systematically characterized in terms of mechanical strength, water absorption capacity, electrical conductivity, antimicrobial performance, and polyvinyl alcohol (PVA) attachment efficiency. Morphological and chemical analyses were conducted using SEM and FTIR techniques to investigate pH-induced structural variations. The results revealed that the BC6 sample (pH 6) exhibited the highest tensile strength (2.4 MPa), elongation (13%), PVA incorporation (12%), and electrical conductivity, confirming the positive impact of near-neutral conditions on nanofiber assembly and functional integration. In contrast, the BC4 sample (pH 4) demonstrated strong antimicrobial activity (log reduction = 3.5) against E. coli, suggesting that acidic pH conditions enhance bioactivity. SEM images confirmed the most cohesive and uniform fiber morphology at pH 6, while FTIR spectra indicated the preservation of characteristic cellulose functional groups across all samples. Overall, this study presents a sustainable and efficient strategy for BC production using food waste and demonstrates that synthesis pH is a key parameter in tuning its functional performance. The optimized BC membranes show potential for biomedical, flexible electronic, and antibacterial material applications, particularly in wearable electrode technologies. Full article

Coastal wetlands are highly threatened by human activities, leading to water quality degradation and biodiversity loss. This study assessed spatial variation in 27 water quality parameters, sediment organic matter, and macroinvertebrate assemblages across 12 sites in the estuarine Cruces River wetland (CRW Ramsar site, southern Chile) during summer 2019. Our analysis identified three areas of sampling stations in the wetland, categorized by trophic gradient and salinity: freshwater (n = 5), mixed (n = 3), and estuary (n = 4). Freshwater sites were characterized by low salinity, turbidity, and high nitrate concentrations. Estuarine sites were characterized by higher salinities and turbidity and low nitrates and total organic carbon (TOC) concentrations, and mixed sites had low salinities, high turbidities, high TOC, and low nitrates. Throughout the CRW, the richness and densities of different invertebrates were recorded. Freshwater stations had higher species richness, and estuary stations had higher abundance. Macroinvertebrates found in the lower reaches of the CRW included species characteristic of estuarine environments, whereas the upper stations were dominated by invertebrates inhabiting low-salinity environments. According to the ordination plot of distance-based redundancy analysis (dbRDA) and distance-based linear model (DistLM), our results indicate that macroinvertebrate assemblages differ significantly among areas of the CRW, primarily due to physicochemical variables (i.e., salinity, total carbon, and dissolved phosphorus). Total organic matter content in sediments was higher in freshwater sites and lower in estuarine sites. Our findings will be used to monitor the wetland and implement appropriate management measures for human activities, thereby protecting and conserving the estuarine Cruces River Ramsar wetland. Full article

Polymeric-based amorphous solid dispersions (ASDs) represent a widely employed strategy for enhancing the oral bioavailability of poorly water-soluble drugs, but their successful implementation in solid dosage forms requires careful optimization of both formulation composition and compaction parameters. In this study, the performance of polymeric-based ASD tablets were investigated using two model active pharmaceutical ingredients (APIs) with distinct glass-forming abilities (GFAs) and physicochemical characteristics: (1) indomethacin (IND, a good glass former) and (2) carbamazepine (CBZ, a poor glass former). ASDs were prepared at various API-to-polyvinylpyrrolidone (PVP) ratios (10:90, 20:80 and 40:60 w/w) and incorporated into round-shaped tablets at different ASD loadings (20% and 50% w/w). The impact of compaction pressure and dwell time on the mechanical properties, disintegration, and supersaturation performance was assessed, both immediately after preparation and following three months of storage at 25 °C and 60% relative humidity. Solid-state analysis confirmed the amorphous state of the APIs and revealed the development of API–polymer molecular interactions. Supersaturation studies under non-sink conditions demonstrated that dissolution behavior was strongly influenced by drug loading, polymer content, and compaction conditions, with CBZ formulations exhibiting faster release but greater susceptibility to performance loss during storage. The comparative evaluation of IND and CBZ highlights the critical role of API properties in determining the physical stability and dissolution performance of ASD tablets, underscoring the need for API-specific design strategies in ASD-based formulation development. Full article

Access to clean drinking water is crucial for any region’s social and economic growth. However, rapid urbanization and industrialization have significantly deteriorated water quality, posing severe pollution threats from domestic, agricultural, and industrial sources. This study presents an innovative framework for assessing water quality in North Bhubaneswar, integrating the Water Quality Index (WQI) with statistical analysis, geospatial technologies, and machine learning models. The WQI, calculated using the Weighted Arithmetic Index method, provides a single composite value representing overall water quality based on several key physicochemical parameters. To evaluate potable water quality across 21 wards in the northern zone, several key parameters were monitored, including pH, electrical conductivity (EC), dissolved oxygen (DO), hardness, chloride, total dissolved solids (TDSs), and biochemical oxygen demand (BOD). The Weighted Arithmetic WQI method was employed to determine overall water quality, which ranged from excellent to good. Furthermore, Principal Component Analysis (PCA) revealed a strong positive correlation (r > 0.6) between pH, conductivity, hardness, and alkalinity. To enhance the accuracy and reliability of water quality assessment, multiple machine learning models Logistic Regression (LR), Decision Tree (DT), Random Forest (RF), Support Vector Machine (SVM), K-Nearest Neighbors (KNN), and Naïve Bayes (NB) were applied to classify water quality based on these parameters. Among them, the Decision Tree (DT) and Random Forest (RF) models demonstrated the highest precision (91.8% and 92.7%, respectively) and overall accuracy (91.7%), making them the most effective in predicting water quality and integrating WQI, machine learning, and statistics to analyze water quality. The study emphasizes the importance of continuous water quality monitoring and offers data-driven recommendations to ensure sustainable access to clean drinking water in North Bhubaneswar. Full article

Assessing the impact of land use and land cover (LULC) on water quality (WQ) is central to land-based environmental research. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, this study analyses recent trends using LULC maps to assess stream WQ within buffers, focusing on papers published between 2020 and 2024. It identifies relevant remote sensing practices for LULC mapping, landscape metrics, WQ physicochemical parameters, statistical techniques for correlating LULC and WQ, and conventions for configuring buffers. Materials include Scopus, Web of Science, and Atlas.ti, which support both qualitative data analysis and Conversational Artificial Intelligence (CAI) tasks via its integration with OpenAI’s large language models. The methodology highlights creating a bibliographic database, coding, CAI, and validating prompts. Official maps and visual or digital interpretations of optical imagery provided inputs for LULC. Classifiers from earlier generations have shaped LULC cartography. The most employed WQ parameters were phosphorus, total nitrogen, and pH. The three most referenced landscape metrics were the Largest Patch Index, Patch Density, and Landscape Shape Index. The literature mainly relied on Redundancy Analysis, Principal Component Analysis, and alternative correlation approaches. Buffer configurations varied in size. CAI facilitated an agile systematic review; however, it encountered challenges related to a phenomenon known as hallucination, which hampers its optimal performance. Full article