Search Results (2,059)

A simple Lagrangian travelling slice model has been successfully used to predict the relations between the process parameters and the strand temperatures in the continuous casting of steel. The present paper aims to include a simple macrosegregation, grain structure and mechanical stress and deformation model on top of the thermal slice framework. The basis of all the mentioned models is the slice heat-conduction model that considers the complex heat extraction mechanisms in the mould, with the sprays, rolls, and through radiation. Its main advantage is the fast calculation time, which is suitable for the online control of the caster. The macroscopic thermal and species transfer models are based on the continuum mixture theory. The macrosegregation model is based on the lever rule microsegregation model. The thermal conductivity and species diffusivity of the liquid phase are artificially enhanced to consider the convection of the melt. The grain structure model is based on cellular automata and phase-field concepts. The calculated thermal field is used to estimate the thermal contraction of the solid shell, which, in combination with the metallostatic pressure, drives the elastic-viscoplastic solid-mechanics models. The solution procedure of all the models is based on the meshless radial basis function generated finite difference method on the macroscopic scale and the meshless point automata concept on the grain structure scale. Simulation results point out the areas susceptible to hot tearing. Full article

The coffee cherry processing produces various waste products, such as coffee husks, which are a valuable source of pectin and phenolic acids that can be used as high-value biomolecules in human and animal food, cosmetics, and pharmaceutical production chains. This study aims to optimize the eco-friendly extraction of polysaccharides, as pectin, and phenolic compounds from coffee peel using response surface methodology (RSM). This model was used to evaluate the extraction variables (temperature, time, pH, ionic strength, ultrasonic frequency, particle size, and solid/liquid ratio in water) to identify the critical factors. All responses were fitted to the RSM model, which revealed high estimation capabilities. Ionic strength and temperature were found to be critical process variables for pectin extraction, while the main factors responsible for phenolic extraction were ultrasonic frequency, pH, and solid/liquid ratio. Therefore, the operating conditions to optimize the extraction of both pectin and phenolic compounds were 80 °C, ultrasonic frequency 60 kHz, solid/liquid ratio 1:20, using pH 2 or 12 in the case of pectin or polyphenols, respectively. Direct Analysis in Real Time Mass Spectrometry (DART-MS) and Fourier-Transform Infrared Spectroscopy–Attenuated Total Reflectance (FTIR-ATR) analyses were performed to evaluate the chemical profile of the extracts and pectin. The recycling of coffee husk waste into bioproducts in view of the circular economy contributes to minimizing the impact on the environment and to generating additional income for coffee growers. Full article

The palo prieto (Lysiloma divaricata) is a tree with grayish bark and pinnate leaves that is native to Mexico. This tree can reach heights close to 15 m and is a source of phytochemical compounds, including polyphenols. The optimized extraction method is important for preserving phytochemical compounds, particularly gallic acid. In general, solid-liquid extraction methods are the most commonly used methods for obtaining phytochemical compounds from Lysiloma divaricata. Herein, we report the results of a complex experimental design in which different parts of the plant (leaf, stem, and fruit) were used to investigate their antioxidant activities and gallic acid contents. In this design, we included variations in the type of solvent, time, and temperature. This method yields an extract rich in phytochemical components that may exhibit significant antioxidant activity, making it suitable for isolating natural antioxidant compounds. For these compounds, bromatological analysis, quantification of phenolic content, and identification and quantification of phytochemical compounds via UPLC-MS/MS identified 27 compounds, with gallic epicatechin, catechin, kaemferol-3-glucoside, procyanidin B1, and gallic acid as the major compounds. For the quantification of gallic acid by HPLC, the highest concentration of gallic acid was detected in the water-leaf-40 °C-90 min fraction. In addition, antioxidant activity via 1,1-diphenyl-1,2-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) was studied, and color measurements were performed. Additionally, the antioxidant activity of the fruit samples was evaluated via the DPPH method with an ethanol/water ratio of 30:70 % v/v at 60 °C for 60 min, which resulted in the highest percentage of inhibition. There was no significant difference in the antioxidant activity when ABTS was used between the samples. For the antioxidant activity determined via FRAP, the leaf sample exhibited the most significant activity when ethanol was used as the solvent at 50 °C for 90 min, with a value of 195,861 ± 44.20 µM eq Trolox/g DM. The phenol compounds of Lysiloma divaricata are promising sources of natural antimicrobials and antioxidants for potential applications in food packaging. Full article

Macroalgae are often used to produce sodium alginate, but their by-products have not been fully utilized. This study aimed to optimize the extraction of bound polyphenols (BPs) from Macrocystis pyrifera (L.) residues, analyze the composition of free polyphenols (FPs) and BPs, and evaluate their antioxidant activities and ability to inhibit glycosidase activity. The optimal conditions for extracting BPs achieved by the response surface method were as follows: 50 °C, a solid–liquid ratio of 1:50, an alkaline hydrolysis time of 2.38 h, and a NaOH concentration of 8 mol/L. Polyphenol content determination results indicated that FPs had significantly higher total polyphenols (13.02 ± 0.05 μg GAE/mg) and phlorotannin (3.44 ± 0.04 μg PE/mg) than BPs (6.57 ± 0.07 μg GAE/mg and 1.32 ± 0.20 μg PE/mg). HPLC/ESI-QTOF-MS showed distinct profiles: FPs had one polyhydroxy phenol, nine flavonoids, and four additional compounds, whereas BPs had five flavonoids and four other compounds. Antioxidant activity was found to be higher in FPs than in BPs (DPPH: 3.03 vs. 1.79 μg TE/mg; FRAP: 19.40 vs. 7.43 μg TE/mg). Furthermore, FPs exhibited 4.59- and 11-fold higher inhibition capacity toward α-amylase and α-glucosidase, respectively, compared to BPs. The results provide valuable basic data for the application of macroalgae residues in the marine biological industry and reveal their potential hypoglycemic ability. Full article

In this study, a green and efficient extraction methodology was developed by leveraging the unique properties of chitosan—namely its non-toxicity, biocompatibility, and adhesive nature—to enhance the recovery of bioactive ingredients from Forsythia suspensa leaves. The core mechanism involves the formation of complexes between chitosan and the target bioactive ingredients, which significantly boosts their extraction efficiency. To substantiate this mechanism, comprehensive characterization was performed using Powder X-ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), and molecular docking analyses. The results provided robust evidence of a strong interaction between chitosan and the bioactive ingredients, leading to a marked enhancement in both the stability and aqueous solubility of the target compounds. For process optimization, a multi-objective approach was implemented using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) to simultaneously maximize the extraction yields of phillyrin and forsythoside A. The algorithm identified the optimal parameters as a leaf-to-chitosan mass ratio of 10:11.75, a solid-to-liquid ratio of 1:52 g/mL, a temperature of 80 °C, and a duration of 120 min. Under these optimized conditions, the corresponding extraction yields for phillyrin and forsythoside A were 1.68 ± 0.16% and 3.23 ± 0.27%, respectively. These findings collectively indicate that chitosan-assisted extraction represents a highly promising and advanced technology for the sustainable and effective extraction of bioactive ingredients from botanical sources. Full article

Background/Objectives: As a non-medicinal part resource of Ziziphus jujuba, this study focuses on the total flavonoids from Ziziphus jujuba mesocarp (TFZJM), aiming to optimize the extraction process and explore its sedative and hypnotic effects. Methods: The extraction process of TFZJM was optimized by using single-factor experiments and the Box-Behnken response surface design method. The material basis of TFZJM was analyzed using Ultra-Performance Liquid Chromatography-Quadrupole-Time of Flight-Mass Spectrometry (UPLC-Q-TOF-MS). The mouse insomnia model was induced by intraperitoneal injection of PCPA, and the effects of TFZJM on this model and its potential mechanism were evaluated using multiple methods, such as sleep enhancement induced by pentobarbital sodium, HE staining of tissue sections, ELISA, RT-PCR, WB, and serum metabolomics. Results: The results showed that by optimizing the extraction conditions, a solid-liquid ratio (SLR) of 1:25 g·mL⁻¹, ethanol concentration of 60%, extraction time of 60 min, and extraction rate of 1.98% were achieved. The common chemical basis of the 10 flavonoid components was identified using UPLC-Q-TOF-MS analysis. Compared with the model group, the high-dose TFZJM (TFZJM-H) group had the most significant effect, followed by the medium-dose (TFZJM-M) and low-dose (TFZJM-L) groups. Conclusions: Metabolomic analysis revealed that TFZJM regulates pathways related to the metabolism of phenylalanine, tyrosine, cytochrome P450, and alanine. This lays the foundation for further exploration of the active substances and mechanisms of action of TFZJM in sedation and hypnosis. Full article

Extraction of metal ions from polluted waters and immobilization of metals in contaminated soils can be conducted using zeolites—porous aluminosilicate ion exchangers. The uptake of copper and zinc ions by the Georgian natural heulandite was studied under conditions of interaction of the zeolite with solutions (“liquid-phase” ion exchange) and powders (“solid-state” ion exchange) of the corresponding salts. The aim of the study was to compare the effect of the two procedures on the chemical composition and structure of the zeolite. It was found that the “liquid-phase” procedure provides a higher degree of uptake, particularly of zinc ions. Ion-exchange causes slight dealumination without decationization. Uptake of divalent ions occurs mainly through the leaching of sodium ions. According to X-ray data of ion-exchanged samples, the uptake of copper and zinc does not change the crystal structure of the zeolite framework, but nitrogen adsorption measurements show that ion exchange affects the mesoporous structure: solution treatment reduces the specific total pore volume and leads to the appearance of pores with a diameter of 4 nm. The “solid-state” procedure leads to an increase in specific total pore volume mainly due to an increase in the number of relatively small nanosized pores. Full article

An innovative ultrasound-assisted deep eutectic solvent-based three-phase partitioning (UA-DES-TPP) system was developed for the sustainable extraction of Ficus carica polysaccharide (FCP). Using a hydrophobic DES composed of dodecanoic acid and octanoic acid (1:1 molar ratio), a phase behavior-driven separation mechanism was established. The system was systematically optimized through single-factor experiments and response surface methodology (RSM), achieving a maximum FCP yield of 9.22 ± 0.20% under optimal conditions (liquid–solid ratio 1:24.2 g/mL, top/bottom phase volume ratio 1:1.05 v/v, ammonium sulfate concentration 25.8%). Structural characterization revealed that FCP was a heteropolysaccharide primarily composed of glucose and mannose with α/β-glycosidic linkages and a loose fibrous network. Remarkably, the DESs demonstrated excellent recyclability over five cycles. Furthermore, FCP exhibited significant concentration-dependent antioxidant activities: 82.3 ± 3.8% DPPH radical scavenging at 8 mg/mL, 76.8 ± 0.8% ABTS⁺ scavenging, and ferric ion reducing power of 45.53 ± 1.07 μmol TE/g. This study provides a new path for the efficient and sustainable extraction of bioactive macromolecules. Full article

Deep eutectic solvents (DESs) have been studied to obtain extracts from medicinal plants, aiming for a more environmentally friendly process. Aligned with this initiative, the use of predictive thermodynamic models for screening the best solvent represents a theoretical action to reduce experimental time and cost. Therefore, this study aimed to perform and validate a relative solubility screening of 5-methoxy-6,7-methylenedioxycoumarin and prenyletin-methyl-ether at 313 K in choline chloride, menthol, and betaine-based DES, using the COSMO-RS model in COSMOThermX software. The density of DES was also predicted with a maximum error of 7.31% for this property. Ultrasound-assisted extraction (UAE) with DES at 313 K, 30 min, and a solid/liquid ratio of 1:20 (w/w) was performed to confirm the theoretical solubility results experimentally, as the extracts were analyzed through ultrafast liquid chromatography (UFLC) for coumarin content. For the results, the coumarin molecules presented intense peaks in the nonpolar region of their σ-profile, and the relative solubility screening indicated the DES Men/Lau (2:1), known for its hydrophobic nature and low polarity, as the best DES to solubilize these coumarins. Nevertheless, the UFLC results, and the complementary solubility screening of pigments, showed an interaction preference of this DES with chlorophylls instead of coumarins. This result was corroborated by spectrophotometric analysis of the extracts in UV-Vis, demonstrating that experimental validation is still mandatory in extraction processes and that predictive methodologies such as COSMO-RS should be used as guiding tools and analyzed in a greater context, considering the complexity of plant matrices in the beginning of simulations. Full article

Opuntia stricta var. dillenii (OPD) fruits are rich in betalains and phenolic compounds, which are recognized for their potential health-promoting properties. This study focuses on the optimization of pulsed electric field (PEF)-assisted solid–liquid green extraction (SLE) from OPD whole fruit, using response surface methodology (RSM) experimental design to obtain green extracts rich in bioactive compounds. The optimal PEF pre-treatment conditions (electric field strength and energy input) were determined based on the cell disintegration index (Zp), followed by optimizing SLE conditions (temperature, time, and ethanol content). High-performance liquid chromatography (HPLC-DAD-ESI-Qtof) was used to characterize the individual bioactive compound profile of the obtained OPD green extracts. Results showed that optimal PEF pre-treatment conditions were at 10.5 kJ/kg and 5 kV/cm, followed by SLE at 35 °C for 165 min, using water as the solvent. Conventional optimal SLE conducted at 45 °C, 8% ethanol, and 128 min was applied as the control process. The combined PEF-assisted SLE process enhanced total betalain and phenolic compound yields by 61% and 135%, respectively. Antioxidant activities (DPPH by 145%, FRAP by 28%) and anti-inflammatory potential (hyaluronidase inhibition by 19%) were also significantly improved. This study underscores the potential use of a PEF pre-treatment to improve obtaining green extracts rich in bioactive compounds with high biological activities from OPD whole fruits, using water as a solvent. Full article

Background/Objectives: This study aimed to develop a nanostructured lipid carrier (NLC) system incorporating a catechin-rich Vanda coerulea extract for topical cosmetic applications and to evaluate its physicochemical properties, release behavior, and skin retention performance. Methods: Blank NLCs were prepared using hot emulsification followed by sonication, with glyceryl monostearate, caprylic triglyceride, Poloxamer^® 188, and Tween^® 80 as the formulation components. NLCs with varying solid-to-liquid lipid ratios were developed while maintaining a constant total lipid content of 5% w/w. The formulations were characterized based on their particle size, polydispersity index (PDI), zeta potential, and physical stability, including stability after a heating–cooling cycle test. The effect of ultrasonication duration was also evaluated. The optimized NLC was then loaded with a V. coerulea extract and evaluated for in vitro release and skin retention using catechin as a marker. Results: The NLC with a particle size of 235.5 ± 29.8 nm, a narrow PDI range of 0.382 ± 0.090, and a strong zeta potential of −29.8 ± 0.3 mV was selected for the incorporation of the V. coerulea extract. The extract-loaded NLC exhibited a sustained release over 24 h, significantly different from the V. coerulea extract solution (p < 0.05). Skin retention studies revealed that the NLC achieved approximately twice the catechin retention compared to the solution at the 1 h time point (1.30 ± 0.01% vs. 0.68 ± 0.03% w/w). Conclusions: The V. coerulea-extract-loaded NLC demonstrated favorable physicochemical properties, sustained release behavior, and enhanced skin retention. These findings support its potential as a promising topical delivery system for antioxidant-rich botanical extracts in cosmetic applications. Full article

Bixin, an apocarotenoid from Bixa orellana seeds, is a valuable natural pigment with industrial and pharmacological applications. Traditional extraction methods rely on organic solvents, but eco-friendly alternatives like silk fibroin solution (SFS) are emerging. This study evaluated SFS for bixin extraction from annatto seeds, optimizing conditions using Box-Behnken Design (BBD). The optimal parameters 1.5% SFS, 60 °C, and 60 min yielded 10.87 mg/mL (liquid extract of annatto seeds, LEAS + SFS) and 150.72 mg/g (solid extract of annatto seeds, SEAS + SFS). Cell viability was assessed in human dermal fibroblasts (HDFn) and RAW 264.7 murine macrophages via MTT assay. After 24 and 72 h, LEAS + SFS, SEAS + SFS, purified bixin (PB), and SFS maintained >70% viability in HDFn cells. Similarly, RAW 264.7 cells showed >70% viability after 24 h, indicating low cytotoxicity. These results highlight the biocompatibility of SFS-extracted bixin, supporting its potential in food, cosmetics, and biomedicine. The study demonstrates that SFS is an effective, sustainable alternative to traditional solvents, offering high extraction efficiency and minimal toxicity. This method aligns with green chemistry principles, providing a promising solution for bixin production. Full article

Functional beverages are increasingly sought as components of a healthy diet, and goat milk offers a nutritious base with unique sensory attributes. This study aimed to develop a novel fermented goat milk beverage enriched with spent coffee grounds (SCG) extract, utilizing SCG’s high natural antioxidant content to improve nutritional and functional properties. SCG was extracted via aqueous solid–liquid extraction and lyophilized; its extract was incorporated into goat milk–fructose blends at 0%, 1%, and 2% (w/v). Analyses included physicochemical characterization (pH, acidity, fat, and protein), total phenolic content, and antioxidant capacity via DPPH assay, alongside consumer sensory evaluation for acceptance and purchase intent. Results demonstrated that higher SCG extract levels significantly increased pH, phenolic concentrations, and radical scavenging activity while reducing titratable acidity. The 2% SCG formulation achieved the highest overall, taste, and aftertaste acceptance and purchase intention. These findings suggest that SCG-enriched goat dairy beverages are feasible functional foods with enhanced antioxidant properties and consumer appeal, promoting valorization of coffee by-products. Full article

A microwave extraction method was developed to isolate antioxidant polysaccharides from Plantago depressa (psyllium), and the structure, free radical-scavenging ability, as well as in vivo antioxidant activity of psyllium polysaccharides were analyzed. The optimal condition for microwave extraction was as follows: duration of microwave radiation of 35 min, extraction temperature of 80 °C, and ratio of liquid to solid of 80:1 (mL/g). The yield of psyllium polysaccharides by microwave extraction was significantly higher than that by heating extraction (p < 0.05). The volumes of P. depressa samples notably increased after microwave extraction, which implied that microwave radiation might loosen the structure of cells and tissues of psyllium leaves and facilitate the exudation of target polysaccharides from leaf samples. The structure of polysaccharides was analyzed by infrared spectroscopy. The effective concentrations of psyllium polysaccharides scavenging DPPH^• and ABTS^•+ radicals by 50% (EC₅₀) were 0.20 and 0.10 mg/mL, respectively. Moreover, P. depressa polysaccharides increased activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in Drosophila melanogaster. In conclusion, microwave extraction seems to be an efficient method to isolate bioactive polysaccharides from P. depressa, which were a potential source of natural antioxidants. Full article

This study aims to develop an environmentally friendly hydrometallurgical process for the recovery of zinc from zinc oxide ores. The process includes monosodium glutamate (MSG) leaching, followed by zinc recovery from the pregnant leach solution via electrowinning, and the recirculation of the spent solution to the leaching stage. The study investigated the effects of key leaching parameters and identified the optimal conditions as a pH of 9.5, temperature of 70 °C, 5 h leaching time, solid-to-liquid ratio of 50 g/L, particle size of d₈₀ = 115 µm, and initial MSG concentration of 1.0 M. Under these conditions, 82.3 ± 0.05% of the zinc was extracted with minimal co-dissolution of impurities. Subsequent electrowinning at 100 A/m² for 150 min yielded 74.97 ± 2.43% zinc recovery with 96.4 ± 0.76% purity. The process achieved a current efficiency of 87.08%, while the specific energy consumption was calculated to be 3.98 kWh per kilogram of zinc recovered. The reusability of MSG was examined by recirculating spent electrowinning solution back to the leaching stage. Zinc extraction decreased from 82.2% to 28.5% over three electrowinning–leaching cycles, due to MSG degradation during electrowinning. The results of this study demonstrated that MSG is a selective and effective lixiviant for zinc recovery, while underlining the limitations of its reuse. Full article