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1.
Ultrason Sonochem ; 109: 107012, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39098098

RESUMO

Ultrasound-assisted extraction (UAE) was evaluated as a green procedure to produce faba beans protein isolates from faba beans. Magnetic stirring was performed as conventional extraction. A three-level five-factor Box-Behnken Design (BBD) was applied to obtain the optimal UAE conditions to concurrently maximize extraction yield and protein content. The response surface methodology (RSM) showed a quadratic curvature for extraction yield and protein. The optimal extraction conditions were determined as: Power of 123 W, solute/solvent ratio of 0.06 (1:15 g/mL), sonication time of 41 min, and total volume of 623 mL with a desirability value of 0.82. Under these conditions, the extraction yield of 19. 75 ± 0.87 % (Protein yield of 67.84 %) and protein content of 92.87 ± 0.53 % were obtained for optimum ultrasound extraction. Control samples using magnetic stirring under similar conditions without ultrasound treatment showed an extraction yield of 16.41 ± 0.02 % (Protein yield of 54.65 %) and a protein content of 89. 88 ± 0.40 %. This shows that BBD can effectively be used to optimize the extraction of proteins from faba beans using optimal extraction conditions, resulting in a higher extraction yield and protein purity.

2.
Sci Total Environ ; 951: 175507, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39147050

RESUMO

Industrial wastewater containing high levels of fluoride and phosphate poses significant environmental challenges and results in the waste of non-renewable resources. This study investigates the use of La(OH)3 as a precipitating agent to selectively remove and separate fluoride from phosphate in such wastewater. The findings indicate that fluoride removal efficiency is highly dependent on the pH level and La(OH)3 dosage. Using Response Surface Methodology, the optimal conditions for fluoride precipitation were identified as a pH range of 1.0 to 2.5, a reaction time of 60-80 min, a La/3F molar ratio of 2.0, and reaction temperature of 25 °C. Under these parameters, the fluoride removal efficiency exceeded 96.9 %, while phosphate removal remained around 7.2 %. Further Density Functional Theory calculations and characterization confirmed La(OH)3 has a strong affinity for fluoride than phosphate under acidic conditions, leading to the formation of a LaF3 precipitate without forming LaPO4, effectively separating fluoride from phosphate. These results demonstrate an efficient strategy for treating wastewater with high fluoride and phosphate content, enabling the selective precipitation and recovery of these elements for sustainable management.

3.
J Biol Eng ; 18(1): 44, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148082

RESUMO

Considerable attention has been paid to exploring the biotechnological applications of several Monascus sp. for pigment production. In this study, our focus is on enhancing the bioprocessing of red pigment (RP) derived from the endophytic fungus Monascus ruber SRZ112. To achieve this, we developed a stable mutant strain with improved productivity through gamma irradiation. This mutant was then employed in the immobilization technique using various entrapment carriers. Subsequently, we optimized the culture medium for maximal RP production using the Response Surface Methodology. Finally, these immobilized cultures were successfully utilized for RP production using a semi-continuous mode of fermentation. After eight cycles of fermentation, the highest RP yield by immobilized mycelia reached 309.17 CV mL-1, a significant increase compared to the original titer. Importantly, this study marks the first report on the successful production of Monascus RP in a semi-continuous mode using gamma rays' mutant strain, offering prospects for commercial production.

4.
Heliyon ; 10(15): e34804, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39157363

RESUMO

In the era of global energy crises and the pressing concern of fossil fuel depletion, the quest for sustainable alternatives has become paramount. The current study aims to optimize biodiesel extraction from a combination of waste cooking oil (WCO) and sesame seed oil (SSO) through response surface methodology (RSM) and artificial neural network (ANN). The cold flow properties of biodiesel produced from WCO are a major obstacle to the commercial use of biodiesel. On the other hand, SSO possesses better oxidation stability and cold flow properties. A mixture of waste cooking oil (i.e. 70 % by volume) and sesame seed oil (i.e. 30 % by volume) has been prepared for biodiesel production via a microwave-assisted transesterification process. For biodiesel yield optimization, the interaction among the operating parameters is developed by RSM, whereas biodiesel yield is predicted by ANN. The operating parameters include reaction speed, RPM (100-600 rpm), reaction time (1-5 min), methanol to oil ratio (8:1-12:1 v/v), and catalyst concentration (0.1-2 % w/w). The highest biodiesel yield of 94 % is found at a reaction speed of 350 rpm, reaction time of 3 min, catalyst concentration of 1.05 w/w, and methanol to oil ratio of 10:1. Furthermore, it is discovered that when estimating biodiesel production rate depending on reaction constraints, ANN shows lower comparative error compared to RSM. The results show that ANN outperforms RSM in terms of percentage improvement when it comes to biodiesel production prediction.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39134794

RESUMO

Chlorophenols are one of the major organic pollutants responsible for the contamination of water bodies. This study explores the application of Ni-Zn/CeO2 nanocomposites, synthesized via the aqueous co-precipitation method, as effective adsorbents for the 4-chlorophenol removal from aqueous solutions. The nanocomposites' chemical and structural characteristics were assessed using different physical characterization methods, viz. X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, zeta potential, using a Box-Behnken design within response surface methodology, optimal conditions of pH 3, temperature 20 °C, contact time 120 min, adsorbent dosage 0.05 g, and 4-chlorophenol concentration 50 ppm are identified. Among the nanocomposites tested, NZC 20:10:70, with 20% Ni and 10% Zn, achieves enhanced performance, removing 99.1% of 4-chlorophenol within 2 h. Adsorption kinetics follow the pseudo-second-order model and equilibrium data fit the Freundlich isotherm. Thermodynamic analysis indicates an exothermic and spontaneous process. The adsorption capacity of NZC 20:10:70 shows significant enhancement, growing from 19.85 mg/g at 10 ppm to 96.33 mg/g at 50 ppm initial concentration. Physical characterization confirms NZC 20:10:70's superior properties, including a high surface area of 118.471 m2/g. Evaluating economic viability, NZC 20:10:70 demonstrates robust reusability, retaining 85% efficiency over eight regeneration cycles. These results highlight NZC 20:10:70 as a promising adsorbent for effective and sustainable chlorophenol removal in water treatment.

6.
Heliyon ; 10(14): e34366, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39114001

RESUMO

This study aimed to evaluate the hydrolysates from orange peel waste (OPW) as the low-cost carbon source for lycopene production. Initially, the dilute acid pretreatment combined with enzymatic hydrolysis of OPW resulted in a total sugar concentration of 62.18 g/L. Meanwhile, a four-month adaptive laboratory evolution (ALE) experiment using a d-galacturonic acid minimal medium resulted in an improvement in the growth rate of our previously engineered Escherichia coli strain for lycopene production. After evolutionary adaptation, response surface methodology (RSM) was adapted to optimize the medium composition in fermentation. The results obtained from RSM analysis revealed that the 5.53 % carbon source of orange peel hydrolysate (OPH), 6.57 g/L nitrogen source, and 30 °C temperature boosted lycopene production in the final strain. Subsequently, the optimized treatment for lycopene fermentation was then conducted in a 5 L batch fermenter under the surveillance of a kinetic model that uses the Logistic equation for strain growth (µm = 0.441 h-1), and Luedeking-Piret equations for lycopene production (Pm = 1043 mgL-1) with growth rate constant (α = 0.1491). At last, lycopene biosynthesized from OPH was extracted and analyzed for qualitative validation. Likewise, its data on phytic acid (between 1.01 % and 0.86 %) and DPPH radical scavenging (between 38.06 % and 29.08 %) highlighted the better antioxidant capacity of lycopene. In conclusion, the OPH can be used as a fermentation feedstock which opens new possibilities of exploiting fruit crop residues for food and pharmaceutical applications.

7.
Water Environ Res ; 96(8): e11099, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39155047

RESUMO

In this study, we employed the response surface method (RSM) and the long short-term memory (LSTM) model to optimize operational parameters and predict chemical oxygen demand (COD) removal in the electrocoagulation-catalytic ozonation process (ECOP) for pharmaceutical wastewater treatment. Through RSM simulation, we quantified the effects of reaction time, ozone dose, current density, and catalyst packed rate on COD removal. Then, the optimal conditions for achieving a COD removal efficiency exceeding 50% were identified. After evaluating ECOP performance under optimized conditions, LSTM predicted COD removal (56.4%), close to real results (54.6%) with a 0.2% error. LSTM outperformed RSM in predictive capacity for COD removal. In response to the initial COD concentration and effluent discharge standards, intelligent adjustment of operating parameters becomes feasible, facilitating precise control of the ECOP performance based on this LSTM model. This intelligent control strategy holds promise for enhancing the efficiency of ECOP in real pharmaceutical wastewater treatment scenarios. PRACTITIONER POINTS: This study utilized the response surface method (RSM) and the long short-term memory (LSTM) model for pharmaceutical wastewater treatment optimization. LSTM predicted COD removal (56.4%) closely matched experimental results (54.6%), with a minimal error of 0.2%. LSTM demonstrated superior predictive capacity, enabling intelligent parameter adjustments for enhanced process control. Intelligent control strategy based on LSTM holds promise for improving electrocoagulation-catalytic ozonation process efficiency in pharmaceutical wastewater treatment.


Assuntos
Análise da Demanda Biológica de Oxigênio , Ozônio , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Ozônio/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Eliminação de Resíduos Líquidos/métodos , Catálise , Purificação da Água/métodos , Eletrocoagulação/métodos , Preparações Farmacêuticas/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-39107645

RESUMO

Waste printed circuit boards (WPCBs) encompass abundant metals (gold, silver, and copper), along with other harmful materials including brominated epoxy resins, plastics, and heavy metals (lead, mercury, and cadmium). Direct burning and landfilling of WPCBs may cause severe health issues and impair the environment. Therefore, sustainable treatment of WPCBs is necessary to recover valuable metals and remove hazardous materials before disposal. The present work investigates the separation of copper-rich metallic fractions from the WPCBs by the combination of hammer milling and ultrasonic irradiation. Initially, discarded mobile phone PCBs are pre-processed and shortened into 1 × 1 cm2. Downscaled WPCBs are fed into the hammer mill to obtain the fine ground powder. The Powdered WPCBs are further processed through ultrasonic treatment to acquire metal-rich fraction. XRD, SEM-EDS, and ICP/AAS analysis revealed that the current technique can efficiently separate the metal-rich fraction without using toxic solvents. Results show the enhancement of copper fraction from 42.73 to 87 wt. % after ultrasonic treatment of WPCBs ground powder. Further, nitric acid leaching has been implemented to metal-rich fractions, and the parameters have been optimized for copper leaching with the assistance of response surface methodology (RSM) of the design of experiments (DOE). Quantitative dissolution (98.96%) of copper occurred using 3.5 M nitric acid within 3 h at 30 °C with 50 GPL pulp density and 500 rpm agitation speed. Finally, the kinetics of the leaching process were studied to conform the kinetics model. Moreover, the activation energy for diffusion (19.075 kJ/mole) and reaction kinetics model (13.29 kJ/mole) has also been calculated. The low energy consumption due to room temperature pre-treatment and effective leaching ensures the industrial feasibility of the proposed process.

9.
J Environ Manage ; 368: 122170, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39137639

RESUMO

The removal of tetracycline antibiotics using adsorbents is becoming an environmentally friendly and cost-effective method. This study systematically analyzed the stability, structure, morphology, and chemical properties of various adsorbents. Batch adsorption experiments (pH, time, temperature, tetracycline concentration, and adsorbent dosage) were conducted to compare the adsorption capacity of the six adsorbents (biochar, activated carbon, montmorillonite, zeolite, chitosan, and polymerized aluminum chloride) for tetracycline removal. The results indicated that montmorillonite had the highest adsorption efficiency, followed by biochar, with chitosan showing the lowest efficiency. At an adsorbent dose of 25 g/L and an initial tetracycline concentration of 120 mg/L, the removal rates of tetracycline by montmorillonite, biochar, and chitosan were 97.6%, 69.3%, and 12.2%, respectively. Furthermore, the removal rate of tetracycline by biochar, following the response surface methodology optimal mode, increased by 5.5%. The Elovich model was better suited to explain the adsorption process of tetracycline compared to the conventional pseudo-first kinetic model and second-order kinetic model. The isothermal adsorption model suggested that both chemisorption and physisorption occurred in all removal processes, in which chemisorption dominated. Tetracycline was efficiently adsorbed through the combined effects of pore filling, electrostatic attraction, π-π interactions, and complexation reactions of surface functional groups. Additionally, montmorillonite demonstrated superior performance as an adsorbent for tetracycline removal from swine wastewater compared to the other adsorbents studied.

10.
J Texture Stud ; 55(4): e12860, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39138115

RESUMO

Sous vide meat is an emerging food category, the consumption of which has increased owing to greater convenience, sensory traits, elderly consumers acceptance, and low-cost cuts use. However, required prolonged thermal treatment to achieve desired tenderness, impact energy-consumption besides triggering lipid oxidation, undesired off-flavors, and cooked meat profiles. Using a response surface methodology (RSM), this study evaluated the effects of the vegetal proteolytic papain (0 to 20 mg/kg) and low-temperature sous vide cooking (SVC) time (1 to 8 h at 65°C) in low-value marinated M. semitendinosus beefsteaks on technological characteristics associated with tenderness, and lipid oxidation. Additionally, the sensory profile traits of the pre-selected treatments were described using check-all-that-apply (CATA) and preference mapping. Shear force (WBsSF) was reduced with greater papain addition, whereas higher cooking losses (CL) were observed with longer SVC cooking times. Both the released total collagen and TBARS values increased with increasing papain concentrations and SVC times. Combining high levels of papain (>10 mg/kg) and SVC time (>6 h) resulted in lower WBsSF values (<20 N) but higher CL (>27%) and the CATA descriptors "aftertaste" and "mushy." The optimized conditions (14 mg/kg papain; 2 h SVC) also reduced WBsSF values (<26 N) with lower CL (<20%) and were most preferred and described as "juicy" and "tender" by consumers. Observed results suggest that combined mild SVC and papain may potentiate tenderness, conjointly favor juiciness and oxidation, further representing a promising tool for reducing SVC time without compromising valued sous vide sensory traits.


Assuntos
Culinária , Papaína , Paladar , Culinária/métodos , Animais , Bovinos , Humanos , Carne Vermelha/análise , Masculino , Carne/análise , Feminino
11.
Colloids Surf B Biointerfaces ; 244: 114134, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39121569

RESUMO

Active pharmaceutical ingredient (API) embedded dry powder for inhalation (AeDPI) shows higher drug loading and delivery dose for directly treating various lung infections. Inspired by the dandelion, we propose a novel kind of AeDPI microparticle structure fabricated by spray freeze drying technology, which would potentially enhance the alveoli deposition efficiency. When inhaling, such microparticles are expected to be easily broken-up into fragments containing API that acts as 'seed' and could be delivered to alveoli aided by the low density 'pappus' composed of excipient. Herein, itraconazole (ITZ), a first-line drug for treating pulmonary aspergillosis, was selected as model API. TPGS, an amphiphilic surfactant, was used to achieve stable primary ITZ nanocrystal (INc) suspensions for spray freeze drying. A series of microparticles were prepared, and the dandelion-like structure was successfully achieved. The effects of feed liquid compositions and freezing parameters on the microparticle size, morphology, surface energy, crystal properties and in vitro aerosol performance were systematically investigated. The optimal sample (SF(-50)D-INc7Leu3-2) in one-way experiment showed the highest fine particle fraction of ∼ 68.96 % and extra fine particle fraction of ∼ 36.87 %, equivalently ∼ 4.60 mg and ∼ 2.46 mg could reach the lung and alveoli, respectively, when inhaling 10 mg dry powders. The response surface methodology (RSM) analysis provided the optimized design space for fabricating microparticles with higher deep lung deposition performance. This study demonstrates the advantages of AeDPI microparticle with dandelion-like structure on promoting the delivery efficiency of high-dose drug to the deep lung.

12.
Heliyon ; 10(14): e34356, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39108881

RESUMO

Indole acetic acid (IAA) is one of the prime communicator playing a chief role in the interaction between host plant and endophytes. IAA produced by the endophytes primarily contributes to plant growth and development. Here, we optimized IAA production by an endophytic fungus Diaporthe terebinthifolli GG3F6 isolated from the asymptomatic rhizome of Glycyrrhiza glabra employing response surface methodology (RSM) and exploring its effect on the host plant biology. The methodology revealed 1.1 fold increases in IAA accumulation. The maximum IAA (121.20 µg/mL) was achieved using tryptophan substrate (1 mg/mL) in Potato dextrose broth (48 g/L) adjusted to pH 12 and incubated at 35 °C for 7 days. The significantly low p-value (p < 0.0001) of the experiment propounded that the model best fits the experimental data, and the independent variables have considerable effects on the production of IAA. Morphologically, the in-vitro grown G. glabra plants showed enhanced root and shoot growth when co-cultivated with the isolated endophytic fungal strain (GG3F6) relative to the control plants. Also, the enhanced accumulation of total phenolic (10.7 %) and flavonoid (10.2 %) in the endophyte treated plants was observed. The optimization of IAA production by an endophytic fungus using (RSM) has not been reported so far. Interestingly, 2.1 fold increase in glycyrrhizin content was recorded in GG3F6 treated in-vitro host plants as compared to the control plants. This suggested a potential use of D. terebinthifolli as a biostimulator for plant and enhanced accumulation of glycyrrhizin. The study highlights the dynamic host-endophyte interaction for exploitation in agricultural and pharmaceutical applications.

13.
Foods ; 13(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39123627

RESUMO

Ultrasound-assisted extraction using response surface methodology was employed to extract marigold flower, resulting in a marigold flower extract (MFE) with elevated levels of total phenolic compounds (TPCs), total flavonoid content (TFC), total carotenoid content (TCC), and antioxidant activity, as assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays, under conditions of 40 °C temperature, 15 min extraction time, and 68% ethanol concentration. The MFE was subsequently encapsulated using spray drying with 45% maltodextrin (MD) (MFE-MD; 1:1, 1:2) and 20% gum arabic (GA) (MFE-GA; 1:2, 1:3). The MD (1:2 ratio) sample showed the highest encapsulation yield, while the 45% MD (1:1 ratio) sample exhibited the highest encapsulation efficiency (p ≤ 0.05). Samples containing 45% MD (1:1 ratio) and 20% GA (1:2 ratio) had the highest moisture content, with the 45% MD (1:1 ratio) sample showing the lowest water activity (p > 0.05). These samples also displayed higher L* and a* values compared to the 20% GA samples, which had increased b* values (p ≤ 0.05). Micrographs of the 20% GA (1:3 ratio) and 45% MD (1:2 ratio) samples revealed spherical shapes with smooth surfaces. The 20% GA (1:2 ratio) microcapsules exhibited the highest total phenolic content (TPC) among the samples (p ≤ 0.05). Thus, ultrasound-enhanced extraction combined with response surface methodology proved effective in producing functional food ingredients from plants.

14.
Plants (Basel) ; 13(15)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39124223

RESUMO

Hyssopus officinalis L. (HO) is, as one of the most prevalently utilized plants, used in traditional medicine to cure various diseases as well as the in food and cosmetic industries. Moreover, HO is a rich source of polyphenols with potent antioxidant properties. However, the studies on the extraction of such compounds from HO are scanty and sparse. This study aims to optimize the extraction of polyphenols and maximize the antioxidant activity in HO extracts. A comprehensive experimental design was employed, encompassing varied extraction parameters to determine the most effective ones. Alongside conventional stirring (ST), two green approaches, the ultrasonic treatment (US) and the pulsed electric field (PEF), were explored, either alone or in combination. The extracted polyphenolic compounds were identified with a high-performance liquid chromatography-diode array detector (HPLC-DAD). According to the results, the employment of ST along with an ethanolic solvent at 80 °C for 150 min seems beneficial in maximizing the extraction of polyphenols from HO, resulting in extracts with enhanced antioxidant activity. The total polyphenol was noted at 70.65 ± 2.76 mg gallic acid equivalents (GAE)/g dry weight (dw) using the aforementioned techniques, and the antioxidant activity was noted as 582.23 ± 16.88 µmol ascorbic acid equivalents (AAE)/g dw (with FRAP method) and 343.75 ± 15.61 µmol AAE/g dw (with the DPPH method). The as-prepared extracts can be utilized in the food and cosmetics industries to bestow or enhance the antioxidant properties of commercial products.

15.
Materials (Basel) ; 17(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39124367

RESUMO

The construction industry's high energy consumption and carbon emissions negatively impact the ecological environment; large-scale construction projects consume much energy and emit a significant amount of CO2 into the atmosphere. Statistics show that 30% of energy loss and 40% of solid waste in the construction industry are generated during construction. Therefore, reducing emissions during construction has significant research potential and value. Many scholars have recently studied eco-friendly building materials to facilitate the use of high-carbon emission materials like cement. Adding fibers to composite materials has become a research hotspot among these studies. Although adding fibers to composite materials has many advantages, it mainly reduces the compressive strength of the composite material. This research used the response surface methodology (RSM) to optimize the raw material ratios and thus improve the performance of plant fiber composite materials. Single-factor experiments were conducted to analyze the effects of grass size, grass content, and quicklime content on the composite materials' compressive strength, flexural strength, and water absorption. The influencing factors and levels for the response surface experiment were determined based on the results of the single-factor analysis. Using the response surface methodology (RSM), a second-order polynomial regression model was established to analyze the interaction effects of the three factors on the composite materials' compressive strength, flexural strength, and water absorption rate. The optimal ratio was determined: the optimized options for grass size, grass content, and quicklime content are 2.0 mm, 8.2 g, and 38 g, respectively. The actual values of compressive strength, flexural strength, and water absorption rate of the composite materials made according to the predicted ratio are 11.425 MPa, 2.145 MPa, and 21.89%, respectively, with a relative error of 8% between the actual and predicted values. X-ray diffraction and scanning electron microscopy were also used to reveal the factors contributing to the relatively high strength of the optimized samples.

16.
Molecules ; 29(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39124995

RESUMO

To address issues of global energy sustainability, it is essential to develop highly efficient bifunctional transition metal-based electrocatalysts to accelerate the kinetics of both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Herein, the heterogeneous molybdenum and vanadium codoped cobalt carbonate nanosheets loaded on nickel foam (VMoCoCOx@NF) are fabricated by facile hydrothermal deposition. Firstly, the mole ratio of V/Mo/Co in the composite is optimized by response surface methodology (RSM). When the optimized composite serves as a bifunctional catalyst, the water-splitting current density achieves 10 mA cm-2 and 100 mA cm-2 at cell voltages of 1.54 V and 1.61 V in a 1.0 M KOH electrolyte with robust stability. Furthermore, characterization is carried out using field emission scanning electron microscopy-energy dispersive spectroscopy (FESEM-EDS), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Density functional theory (DFT) calculations reveal that the fabricated VMoCoCOx@NF catalyst synergistically decreases the Gibbs free energy of hydrogen and oxygen-containing intermediates, thus accelerating OER/HER catalytic kinetics. Benefiting from the concerted advantages of porous NF substrates and clustered VMoCoCOx nanosheets, the fabricated catalyst exhibits superior electrocatalytic performance. This work presents a novel approach to developing transition metal catalysts for overall water splitting.

17.
Molecules ; 29(15)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39125062

RESUMO

This study aims to extract phenolic-enriched compounds, specifically oleuropein, luteoloside, and hydroxytyrosol, from olive leaves using ball milling-assisted extraction (BMAE). Response surface methodology (RSM) and the Box-Behnken design (BBD) were used to evaluate the effects of the temperature, solvent-to-solid ratio, and milling speed on extraction recovery. The contents of the extract were determined by ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS) and converted to recoveries to evaluate the extraction efficiency. The optimal extraction conditions for oleuropein, luteoloside, and hydroxytyrosol were identified. Oleuropein had a recovery of 79.0% ± 0.9% at a temperature of 56.4 °C, a solvent-to-solid ratio of 39.1 mL/g, and a milling speed of 429 rpm. Luteoloside's recovery was 74.6% ± 1.2% at 58.4 °C, 31.3 mL/g, and 328 rpm. Hydroxytyrosol achieved 43.1% ± 1.3% recovery at 51.5 °C, 32.7 mL/g, and 317 rpm. The reason for the high recoveries might be that high energy ball milling could reduce the sample size further, breaking down the cell walls of olive leaves, to enhance the mass transfer of these components from the cell to solvent. BMAE is displayed to be an efficient approach to extracting oleuropein, luteoloside, and hydroxytyrosol from olive leaves, which is easy to extend to industrial production.


Assuntos
Glucosídeos Iridoides , Olea , Fenóis , Extratos Vegetais , Folhas de Planta , Olea/química , Folhas de Planta/química , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/análise , Extratos Vegetais/química , Glucosídeos Iridoides/química , Cromatografia Líquida de Alta Pressão/métodos , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/química , Álcool Feniletílico/isolamento & purificação , Iridoides/química , Iridoides/isolamento & purificação , Espectrometria de Massas , Solventes/química
18.
Heliyon ; 10(15): e35685, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39170107

RESUMO

Functional herbal beverages are gaining popularity in the beverage industry due to their natural antioxidants. However, the high concentration of antioxidants in these beverages can lead to increased toxicity, limiting their use. Moreover, the composition of tap water, including mineral salts and hydrogen carbonate ions, hampers the extraction process of polyphenolic compounds, thereby reducing the antioxidant properties. This study aims to address these challenges by enhancing antioxidant properties, reducing toxic effects, and improving the extraction process. Low-dose herbal extracts of green tea, rosemary, milk thistle, and sage were extracted using 100 ml of boiling water as a solvent, with ultrasonication employed for 20 min. Taurine, vit. C, and their combination were added to the extracts. The antioxidant properties, polyphenol, and flavonoid content were evaluated. The results demonstrated that the low-dose herbal tea combined with taurine and vit. C exhibited higher antioxidant activity compared to high-dose tea. Notably, the combination of taurine and vit. C showed the strongest synergistic effect. The addition of vit. C to these combinations eliminated any antagonism and resulted in a robust synergistic effect. The optimal conditions for enhancing antioxidant properties were determined as follows: an herbal type of 0.030 ≈ 0 (sage), vit. C concentration of 0.045 g/100 ml, and taurine concentration of 0.179 g/100 ml. The measured responses for reducing power, DPPH, and ABTS were 0.152 µg vit. C equivalent/ml, 67.778 %, and 87.630 %, respectively. This study provides valuable insights into optimizing the antioxidant properties of herbal beverages through the synergistic combinations of taurine and vit. C. By employing proper preparation techniques and including taurine and vit. C, the antioxidant capacity of these beverages can be significantly improved, potentially offering health benefits against degenerative diseases.

19.
Heliyon ; 10(15): e35398, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39170281

RESUMO

Microorganisms have emerged as promising resources for producing economical and sustainable bioproducts like Polyhydroxyalkanoate (PHA), a biodegradable polymer that can replace synthetic plastics. In this study, we screened a novel isolate, Bacillus paranthracis RSKS-3 strain, to produce PHA from sewage water, identifying it using Whole Genome Sequence. This study represents the first report on optimizing PHA production using B. paranthracis RSKS-3, employing Design Expert 12.0 software. Our findings reveal that four factors (temperature, inoculum size, potassium dihydrogen phosphate, and magnesium sulfate) significantly affect PHA production in the Plackett-Burman design experiment. Through Response Surface Methodology, we optimized PHA production to 0.647 g/L with specific values for potassium dihydrogen phosphate (0.55 %), inoculum size (3 %), magnesium sulfate (0.055 %), and a temperature of 35 °C, in agreement with the predicted value of 0.630 g/L. This optimization resulted in a substantial 13.29-fold increase in PHA production from 0.34 g/L to 4.52 g/L, underscoring the promising role of B. paranthracis RSKS-3 in eco-friendly PHA production and advancing sustainable bioproduct development.

20.
Heliyon ; 10(15): e35554, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39170290

RESUMO

Composite materials have become prominent in the aerospace, automotive, wind energy, biomedical, and machine tool industries. This has demanded the evaluation of the dynamic mechanical and tribological behaviour of composites to understand their performance and ensure their reliability and safety in varied operating conditions. In this study, the effect of halloysite nano-clay addition on the dynamic mechanical and tribological properties of the carbon/glass hybrid composites was investigated. The composites were produced with the vacuum assisted resin infusion process. by varying the content of halloysite nano-clay (1, 3, and 5 wt%). The dynamic mechanical properties of the manufactured composites were examined at temperatures ranging from 30 °C to 180 °C. The tribological properties of the specimens were assessed by varying the applied load (10, 20, and 30 N), sliding speed (1.5, 3, and 4.5 m/s) and sliding distance (500, 1000, and 1500 m). Box-Behnken design was utilized to optimize the number of experiments. The results showed that the halloysite-added samples had better dynamic mechanical and tribological properties than the carbon/glass hybrid composites. Especially, hybrid composites containing 3 wt% halloysite outperformed the other composites investigated. A scanning electron microscope (SEM) was used to examine the worn surface and wreckage in the investigated composite specimens.

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