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1.
Molecules ; 29(14)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39064970

RESUMO

Methylene blue dye in water sources can pose health risks to humans, potentially causing methemoglobinemia, a condition that impairs the blood's ability to carry oxygen. Hence, the current study investigates the synthesis of novel magnesium borate/magnesium oxide (Mg3B2O6/MgO) nanostructures and their efficiency in removing methylene blue dye from aqueous media. The nanostructures were synthesized using the Pechini sol-gel method, which involves a reaction between magnesium nitrate hexahydrate and boric acid, with citric acid acting as a chelating agent and ethylene glycol as a crosslinker. This method helps in achieving a homogeneous mixture, which, upon calcination at 600 and 800 °C, yields Mg3B2O6/MgO novel nanostructures referred to as MB600 and MB800, respectively. The characterization of these nanostructures involved techniques like X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, N2 gas analyzer, and field-emission scanning electron microscope (FE-SEM). These analyses confirmed the formation of orthorhombic Mg3B2O6 and cubic MgO phases with distinct features, influenced by the calcination temperature. The mean crystal size of the MB600 and MB800 samples was 64.57 and 79.20 nm, respectively. In addition, the BET surface area of the MB600 and MB800 samples was 74.63 and 64.82 m2/g, respectively. The results indicated that the MB600 sample, with its higher surface area, generally demonstrated better methylene blue dye removal performance (505.05 mg/g) than the MB800 sample (483.09 mg/g). The adsorption process followed the pseudo-second-order model, indicating dependency on available adsorption sites. Also, the adsorption process matched well with the Langmuir isotherm, confirming a homogeneous adsorbent surface. The thermodynamic parameters revealed that the adsorption process was physical, exothermic, and spontaneous. The MB600 and MB800 nanostructures could be effectively regenerated using 6 M HCl and reused across multiple cycles. These findings underscore the potential of these nanostructures as cost-effective and sustainable adsorbents for methylene blue dye removal.

2.
ACS Omega ; 9(4): 4870-4880, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313534

RESUMO

The discharge of congo red dye into water sources by factories has been associated with a range of health concerns, such as cancer, redness, skin irritation, and allergic reactions. As a result, this research focused on the cost-effective and straightforward production of MgAl2O4 nanoparticles by using the Pechini sol-gel process. Subsequently, these nanoparticles were employed for the successful photocatalytic decomposition of congo red dye. Moreover, extensive characterization of the fabricated MgAl2O4 nanoparticles was conducted through diverse methodologies, which included Fourier-transform infrared spectroscopy, ultraviolet-visible spectrophotometry, high-resolution transmission electron microscopy (HR-TEM), field-emission scanning electron microscopy (FE-SEM), and powder X-ray diffraction (XRD). Furthermore, the XRD analysis disclosed that the average crystal size of the produced MgAl2O4 nanoparticles is 10.36 nm, and their optical energy gap was determined to be 3.71 eV. The FE-SEM examination unveiled a combination of spherical and disorganized structures with a 0.14 µm average grain size. HR-TEM analysis, in turn, revealed that the fabricated MgAl2O4 nanoparticles were composed of minuscule spherical particles with an average diameter of 8.75 nm. The maximum degradation of 50 mL of congo red dye at a concentration of 25 mg/L reached 99.27% within 80 min at a pH of 3. Additionally, the findings confirmed the consistent decomposition activity toward congo red dye even after four cycles, thereby validating the effectiveness and reusability of the MgAl2O4 nanoparticles that were developed in this study.

3.
ACS Omega ; 9(4): 4300-4316, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313481

RESUMO

This study reports for the first time the adsorption capacity of a novel adsorbent Croton bonplandianus Baill. biochar. Its adsorption capacity was further enhanced by loading magnetic composites on it, which makes it an efficient medium for the adsorption of dyes. Two azo dyes, Basic Brown 1 (BB1) and Basic Orange 2 (BO2), were studied for their effective adsorption from aqueous media. A comprehensive characterization was performed by using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) to study the properties of Fe2O3-loaded C. bonplandianus Baill. biochar (FO-CBPBB). A series of batch experiments were conducted to optimize various parameters (pH, contact time, adsorbent amount, initial BB1 and BO2 concentrations, and temperature) for the maximum adsorption of BB1 and BO2 on the FO-CBPBB adsorbent. The percentage of BB1 and BO2 dyes that adsorb to FO-CBPBB under the best experimental circumstances (pH of solution 7, contact time 80 min, temperature of solution 40 °C, initial BB1 and BO2 dye concentrations 80 mg L-1, and adsorbent dose 1 g L-1) was 93 and 95%, respectively. The best adsorption of BB1 and BO2 was accomplished by optimizing the effects of several factors, including the starting dye concentration, contact time, and temperature, based on the central composite design. The Freundlich and Langmuir isotherm models were used to examine the equilibrium data. The Langmuir isotherm with the greatest adsorption capacity and R2 value effectively captured the experimental results. When kinetic parameters were investigated, it was found that pseudo-second-order was appropriate, reflecting the fact that the dye-adsorbent interaction was the rate-controlling factor in this study. The sorption process was endothermic and spontaneous, as shown by the thermodynamic variables. Based on the interaction between the adsorbent and azo dyes, it was concluded that the adsorption process was electrostatic in nature. Adsorbents that have been synthesized can effectively remove azo dyes from wastewater. Excellent regeneration efficiency was exhibited by FO-CBPBB, which makes it an eco-friendly and cost-effective alternative to other costly techniques applied for water purification.

4.
Heliyon ; 10(10): e31351, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38831816

RESUMO

Water pollution represents one of the most important problems affecting the health of living organisms, so it was necessary to work on the formation of active materials to get rid of pollutants. In this study, Titanium dioxide (TiO2) doping Zinc oxide (ZnO) nanocomposites were produced via simple sonication method at 500 Hz in ethanol medium. At different weight concentrations (2.5, 5, 7.5, and 10 %). The morphology, structure configuration, chemical bonding, crystalline phase, and surface properties of obtained nanocomposites were characterized via FESEM, BET, XRD, XPS, RAMAN and FTIR instrumentation. The nanocomposites were employed as an adsorbent to eliminate the methyl orange (MO) and Indigo Carmine (IC) dyes from an aqueous solution. Batch removal experiments revealed that the elimination of MO and IC dyes by the TiZnO surface was pH and doping Ti concentration-dependent, with maximum removal occurring at pH = 7 for MO and pH = 3 for IC contaminants at 10 % doping Ti concentration (Ti (10 %)@ZnO). Langmuir model fit the absorptive removal of MO and IC dyes into the Ti (10 %)@ZnO surface well. The maximal removal capacity of Ti (10 %)@ZnO nanocomposite was found to be 994.24 mg. g-1 for MO and 305.39 mg. g-1 for IC. The Ti (10 %)@ZnO nanocomposite showed remarkable high stability towards the removal of both dyes through consecutive four cycles.

5.
Int J Biol Macromol ; 259(Pt 2): 129190, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185304

RESUMO

Urease is one of the most significant enzymes in the industry. The objective of this research was to isolate and partially purify urease from Vicia sativa seeds with urease characterization. With a 6.4 % yield, the purification fold was 9.0. By using chromatography, it was determined that the isolated urease had a molecular weight of 55 kDa. The maximum urease activity was found following a 60-s incubation period at 40 °C and pH 8. The activity of urease was significantly boosted by a mean of calcium, barium, DL-dithiothreitol, Na2EDTA, and citrate (16.9, 26.6, 18.6, 13.6, and 31 %), respectively. But nickel and mercury caused inhibitory effects and completely inhibited urease activity, indicating the presence of a thiol (-SH) group in the enzyme active site. The Arrhenius plot was used to analyze the thermodynamic constants of activation, Ea, ΔH*, ΔG*, and ΔS*. The results showed that the values were 30 kJ/mol, 93.14 kJ/mol, 107.17 kJ/mol/K, and -40.80 J/mol/K, respectively. The significance of urease extraction from various sources may contribute to our understanding of the metabolism of urea in plants. The current report has novelty as it explained for the first time the kinetics and thermodynamics of hydrolysis of urea and inactivation of urease from V. sativa seeds.


Assuntos
Urease , Vicia sativa , Urease/metabolismo , Vicia sativa/metabolismo , Termodinâmica , Sementes/metabolismo , Ureia/metabolismo , Cinética , Concentração de Íons de Hidrogênio
6.
Sci Rep ; 14(1): 15380, 2024 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965268

RESUMO

Concerns about challenges with water availability in the Tadla Plain region of Morocco have grown as a result of groundwater contamination brought on by human activity, climate change, and insufficient groundwater management. The objective of the study is to measure the number of resistant bacteria in the groundwater of Beni Moussa and Beni Aamir, as well as to evaluate the level of water pollution in this area. 200 samples were therefore gathered from 43 wells over the course of four seasonal campaigns in 2017 and 2018. Additionally, the samples were examined to determine whether Salmonella species were present and if they were resistant to the 16 antibiotics that were tested. Salmonella spp. have been identified in 31 isolated strains in total, accounting for 18.02% of all isolated strains. Data on antibiotic resistance show that 58.1% of Salmonella spp. strains are multidrug-resistant (MDR); 38.7% of Salmonella strains are tolerant to at least six antibiotics, 19.4% to at least nine antibiotics, 9.7% to four to seven antibiotics, 6.5% to at least eleven antibiotics, and the remaining 3.2% to up to twelve antibiotics. A considerable level of resistance to cefepime (61.29%), imipenem (54.84%), ceftazidime (45.16%), ofloxacin (70.97%), and ertapenem (74.19%) was found in the data. Consequently, it is important to monitor and regulate the growth of MDR in order to prevent the groundwater's quality from declining.


Assuntos
Antibacterianos , Água Subterrânea , Salmonella , Marrocos , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Antibacterianos/farmacologia , Água Subterrânea/microbiologia , Humanos , Microbiologia da Água , Testes de Sensibilidade Microbiana , Incidência , Poços de Água , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla
7.
Int J Biol Macromol ; 277(Pt 1): 134026, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39048014

RESUMO

The purple acid phosphatase was purified from 5.9-fold to apparent homogeneity from Anagelis arvensis seeds using SP-Sephadex C-50 and Sephadex G-100 chromatography. The results of residual activity tests conducted using different temperature ranges (50-70 °C) were calculated as the activation energy (Ed = 72 kJ/mol), enthalpy (69.31 ≤ (ΔH° ≤ 69.10 kJ/mol), entropy (-122.48 ≤ ΔS° ≤ -121.13 J/mol·K), and Gibbs free energy (108.87 ≤ ΔG° ≤ 111.25 kJ/mol) of the enzyme irreversible denaturation. These thermodynamic parameters indicate that this novel PAP is highly thermostable and may be significant for use in industrial applications. However, it may be confirmed by stopped-flow measurements that this substitution produces a chromophoric Fe3+ site and a Pi-substrate interaction that is about ten times faster. Additionally, these data show that phenyl phosphate hydrolysis proceeds more rapidly in metal form of A. arvensis PAP than the creation of a µ-1,3 phosphate complex. The Fe3+ site in the native Fe3+-Mn2+ derivative interacts with it at a faster rate than in the Fe3+-Fe2+ form. This is most likely caused by a network of hydrogen bonds between the first and second coordination spheres. This suggests that the choice of metal ions plays a significant role in regulating the activity of this enzyme.

8.
Int J Biol Macromol ; 265(Pt 2): 131067, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38521328

RESUMO

Researchers are consistently investigating novel and distinctive methods and materials that are compatible for human life and environmental conditions This study aimed to synthesize gold nanoparticles (ALPs-AuNPs) using for the first time an alkaline protease (ALPs) derived from Phalaris minor seed extract. A series of physicochemical techniques were used to inquire the formation, size, shape and crystalline nature of ALPs-AuNPs. The nanoparticles' ability to degrade methylene blue (MB) through photocatalysis under visible light irradiation was assessed. The findings demonstrated that ALPs-AuNPs exhibited remarkable efficacy by destroying 100 % of MB within a mere 30-minute irradiation period. In addition, the ALPs-AuNPs demonstrated remarkable effectiveness in inhibiting the growth of gram-positive (S. aureus) and gram-negative (E. coli) bacteria. The inhibition zones examined against the two bacterial strains were 23(±0.3) mm and 19(±0.4); 13(±0.3) mm and 11(±0.5) mm under light and dark conditions respectively. The ALPs-AuNPs exhibited significant antioxidant activity by effectively scavenging 88 % of stable and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. As a result, the findings demonstrated that the environmentally friendly ALPs-AuNPs showed a strong potential for MB degradation and bacterial pathogen treatment.


Assuntos
Proteínas de Bactérias , Endopeptidases , Ouro , Nanopartículas Metálicas , Humanos , Ouro/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Escherichia coli , Staphylococcus aureus/metabolismo , Bactérias , Extratos Vegetais/química
9.
Discov Nano ; 18(1): 97, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37507521

RESUMO

The release of malachite green dye into water sources has detrimental effects on the liver, kidneys, and respiratory system. Additionally, this dye can impede photosynthesis and disrupt the growth and development of plants. As a result, in this study, barium titanate nanoparticles (BaTiO3) were facilely synthesized using the Pechini sol-gel method at 600 °C (abbreviated as EA600) and 800 °C (abbreviated as EA800) for the efficient removal of malachite green dye from aqueous media. The Pechini sol-gel method plays a crucial role in the production of barium titanate nanoparticles due to its simplicity and ability to precisely control the crystallite size. The synthesized barium titanate nanoparticles were characterized by several instruments, such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy, and a diffuse reflectance spectrophotometer. The XRD analysis confirmed that the mean crystallite size of the EA600 and EA800 samples is 14.83 and 22.27 nm, respectively. Furthermore, the HR-TEM images confirmed that the EA600 and EA800 samples exhibit irregular and polyhedral structures, with mean diameters of 45.19 and 72.83 nm, respectively. Additionally, the synthesized barium titanate nanoparticles were utilized as catalysts for the effective photocatalytic decomposition of malachite green dye in aqueous media. About 99.27 and 93.94% of 100 mL of 25 mg/L malachite green dye solution were decomposed using 0.05 g of the EA600 and EA800 nanoparticles within 80 min, respectively. The effectiveness of synthesized BaTiO3 nanoparticles as catalysts stems from their unique characteristics, including small crystallite sizes, a low rate of hole/electron recombination owing to ferroelectric properties, high chemical stability, and the ability to be regenerated and reused multiple times without any loss in efficiency.

10.
RSC Adv ; 13(9): 5656-5666, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36798746

RESUMO

Nanomaterials are the most effective class of substances for use as adsorbents in wastewater treatment. Hence, the current study involves the facile and low-cost synthesis of MgMn2O4/Mn2O3 and MgMn2O4/Mn2O3/Mg6MnO8 as novel nanostructures from mixed solutions of Mg(ii) and Mn(ii) ions using the Pechini sol-gel method. After that, the remaining powder was calcined at 500, 700, and 900 °C for 3 h; the products were designated as G500, G700, and G900, respectively. The G500 sample consists of MgMn2O4 and Mn2O3, while the G700 and G900 samples consist of MgMn2O4, Mg6MnO8, and Mn2O3. The synthesized nanostructures were characterized using several tools, such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and N2 adsorption/desorption analysis. The average crystallite size of the G500, G700, and G900 samples is 210.53, 95.27, and 83.43 nm, respectively. The SEM images showed that the G500 sample consists of square and rectangular bars with an average diameter of 3.18 µm. Also, the G700 and G900 samples consist of hexagonal, polyhedral, and irregular shapes with an average diameter of 1.12 and 0.54 µm, respectively. The synthesized nanostructures were further utilized as adsorbents for the efficient removal of tartrazine dye from aqueous media. The experimental data showed a good fit with the Langmuir isotherm and pseudo-first-order model. The maximum adsorption capacities of the G500, G700, and G900 adsorbents toward tartrazine dye are 328.95, 359.71, and 395.26 mg g-1, respectively.

11.
ACS Omega ; 8(17): 15276-15287, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37151541

RESUMO

In this work, silica nanoparticles were modified by 5-chloro-8-quinolinol as a new nanocomposite for the efficient elimination and preconcentration of Al3+ ions from several water sources. The fabricated composite was characterized utilizing XRD, SEM, FT-IR, TEM, CHN elemental analyzer, and N2 adsorption/desorption analyzer. The XRD demonstrated the existence of a wide peak at 2θ = 30°. Also, all the peaks of silica were severely reduced, which confirms the success of loading the 5-chloro-8-quinolinol on the surface of the silica. The SEM and TEM images demonstrated that the composite resembled cotton, and this confirms that 5-chloro-8-quinolinol was successfully loaded on the silica surface. The specific surface area, the average pore size, and the total pore volume of the synthesized composite are 80.53 m2/g, 3.26 nm, and 0.185 cc/g, respectively. In addition, the greatest uptake capacity of the synthesized composite toward aluminum ions is 95.06 mg/g. The results indicated that the adsorption of aluminum ions onto the silica/5-chloro-8-quinolinol composite follows the Langmuir isotherm and pseudo-second-order model. Moreover, the adsorption of aluminum ions by the silica/5-chloro-8-quinolinol composite is spontaneous, chemical, and thermodynamically favorable. The values of % recovery were more than 97%, whereas the values of % RSD were less than 3.5%. Hence, this confirms the effectiveness of the proposed method in the determination of aluminum ions in real water samples.

12.
Eur J Pharm Sci ; 189: 106555, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37543064

RESUMO

pH-responsive hydrogels have become effective and attractive materials for the controlled release of drugs at pre-determined destinations. In the present study, a novel hydrogel system based on Prunus armeniaca gum (PAG) and acrylic acid (AA) was prepared by a free radical mechanism using N, N-methylene bisacrylamide (MBA) as cross-linker and potassium persulfate (KPS) as initiator. A series of hydrogels varying PAG, AA, and MBA concentration was developed to determine the impact of these components. Formulated hydrogels were characterized for pH-responsive swelling, drug release, gel content, and porosity. Structural analysis was performed by FTIR, XRD, and SEM analysis. TGA study was applied to assess thermal stability. Oral acute toxicity and in vivo drug release were performed in rabbits. Hydrogels exhibited pH-dependent swelling and drug release. Swelling, drug loading and release, and porosity increased by increasing PAG and AA concentration while decreased by increasing MBA. The gel content of formulations was increased by increasing all three components. FTIR studies confirmed the development of copolymeric networks and the loading of drug. XRD studies revealed that hydrogels were amorphous, and the crystalline drug was changed into an amorphous form during loading. TGA results indicated that hydrogels were stable up to 600 °C. Acute oral toxicity results confirm that hydrogels were nontoxic up to a dose of 2 g/kg body weight in rabbits. The pharmacokinetic evaluation revealed that hydrogels prolonged the availability of the drug and the peak plasma concentration of the drug was obtained in 6 h as compared to the oral solution of the drug. Tramadol hydrochloride (THC) was used as a model drug. Hence, pH-responsive swelling and release, nontoxic nature and improved pharmacokinetics support that PAG-based hydrogels may be considered as potential controlled-release polymeric carriers.


Assuntos
Prunus armeniaca , Animais , Coelhos , Hidrogéis/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Polímeros , Concentração de Íons de Hidrogênio
13.
Discov Nano ; 18(1): 70, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37382736

RESUMO

In the water purification field, heavy metal pollution is a problem that causes severe risk aversion. This study aimed to examine the disposal of cadmium and copper ions from aqueous solutions by a novel Fe3O4/analcime nanocomposite. A field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction were used to characterize the synthesized products. The FE-SEM images showed that the analcime and Fe3O4 samples consist of polyhedral and quasi-spherical shapes with average diameters of 923.28 and 28.57 nm, respectively. Besides, the Fe3O4/analcime nanocomposite consists of polyhedral and quasi-spherical shapes with average diameters of 1100.00 nm. The greatest uptake capability of the Fe3O4/analcime nanocomposite toward the copper and cadmium ions is 176.68 and 203.67 mg/g, respectively. The pseudo-second-order kinetic model and Langmuir equilibrium isotherm best describe the uptake of copper and cadmium ions using the Fe3O4/analcime nanocomposite. The uptake of copper and cadmium ions using the Fe3O4/analcime nanocomposite is exothermic and chemical in nature.

14.
Heliyon ; 9(11): e22001, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027594

RESUMO

The utilization of dye adsorption through metal-organic frameworks represents an eco-friendly and highly effective approach in real water treatment. Here, ultrasound assisted adsorption approach was employed for the remediation of three dyes including methylene blue (MB), malachite green (MG), and congo red (CR) from real water samples using zirconium(IV)-based adsorbent (UiO-66-NH2). The adsorbent was characterized for structural, elemental, thermal and morphological features through XRD, XPS, FTIR, thermogravimetric analysis, SEM, BET , and Raman spectroscopy. The adsorption capacity of adsorbent to uptake the pollutants in aqueous solutions was investigated under different experimental conditions such as amount of UiO-66-NH2 at various contact durations, temperatures, pH levels, and initial dye loading amounts. The maximum removal of dyes under optimal conditions was found to be 938, 587, and 623 mg g-1 towardMB, MG, and CR, respectively. The adsorption of the studied dyes on the adsorbent surface was found to be a monolayer and endothermic process. The probable mechanism for the adsorption was chemisorption and follows pseudo-second-order kinetics. From the findings of regeneration studies, it was deduced that the adsorbent can be effectively used for three consecutive cycles without any momentous loss in its adsorption efficacy. Furthermore, UiO-66-NH2 with ultrasound-assisted adsorption might help to safeguard the environment and to develop new strategies for sustainability of natural resources.

15.
Anal Methods ; 15(45): 6275-6285, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-37955946

RESUMO

Sulfite is a very important species, affecting human health, plant and animal life, and environmental sustainability. In this study, for the first time, an ionophore-based ion-selective optode was constructed for hydrogen sulfite determination in beverages, such as Birell® and Sprite®, water, and soil samples; instead of normal pH-chromoionophores, polyaniline film was precipitated on a glass slide and used for the transduction of the sensation mechanism. The ionophore-modified polyaniline-based optode incorporated thiourea derivative as an ionophore and tridodecyl methyl ammonium chloride as an ion-exchanger. The optode film was prepared in situ with a modified chemical polymerization method, and it was characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM), and X-ray diffraction (XRD); also, FTIR spectroscopy was performed for the film before and after interaction with hydrogen sulfite for mechanism elucidation. The optode was applied in the hydrogen sulfite concentration range of 10-1 to 10-5 M with a low detection limit of 8.0 × 10-6 M and minimum interference of other interfering species, such as salicylate, iodide, and sulphide. The response mechanism was due to the ion-exchange of hydrogen sulfite with the anion exchanger, followed by the molecular recognition between thiourea ionophore and hydrogen sulfite, with concomitant redox reaction via the protonation of the polyaniline that causes a decrease in absorbance at 685 nm. The optode was applied successfully for the determination of hydrogen sulfite in real beverages, Birell® and Sprite® without any pretreatment steps. Also, it was applied successfully for the environmental monitoring of hydrogen sulfite in real wastewater and soil samples.


Assuntos
Solo , Águas Residuárias , Humanos , Concentração de Íons de Hidrogênio , Ionóforos/química , Sulfitos , Tioureia
16.
Environ Sci Pollut Res Int ; 30(51): 110658-110673, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37792184

RESUMO

Heavy metals (HMs) in water are highly poisonous and carcinogenic agents for human health. To alleviate the toxic impacts of HMs, green remediation technologies are the need of the hour. In this regard, different nanosorbents (CMCG@ORP, ORAC, NiO/NPs, and NiO@ORAC/NCs) were synthesized in the present study, and the percentage removal of heavy metals [chromium(VI) and cadmium(II) ions] was evaluated. The nanosorbents were characterized by using FTIR, SEM, UV-Vis spectroscopy, and XRD. UV-Vis spectroscopy confirmed the synthesis of nanosorbents such as NiO/NPs and NiO@ORAC/NCs at 330.5 nm and 352.55 nm, respectively. The characterization studies show that the surface of synthesized nano-sorbents was highly coarse, uneven, and abrasive. XRD pattern deduced that the sample was of single phase, and no other impurity was detected except the face-centered cubic-phase peak of NiO. The maximum adsorption of Cd (91%) and Cr (92%) was found at initial concentrations of 100 and 60 ppm respectively at contact time = 180 min, temperature 25 °C, and with an adsorbent dose of 0.5 g. Isothermal, kinetic, and thermodynamic studies were also performed to evaluate the adsorption mechanisms and feasibility of the process. Adsorption mostly followed Freundlich isotherm which indicates the multilayer adsorption phenomenon and the negative value of Gibb's free energy showed the spontaneous nature and feasibility of the adsorption reaction. Surface complexation, ion exchange, surface precipitation, and the phenomenon of physical adsorption occurred on the sorbent surface which led to the attachment of Cd and Cr to the tested nanosorbents. In conclusion, NiO@ORAC/NCs were the most effective in the alleviation of Cd(II) and Cr(VI) ions in contaminated water.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Humanos , Cádmio , Adsorção , Poluentes Químicos da Água/análise , Cromo/química , Água/química , Termodinâmica , Cinética , Concentração de Íons de Hidrogênio
17.
Int J Biol Macromol ; 233: 123544, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36754264

RESUMO

The present work aims to purify and perform a preliminary analysis on a thermostable serine alkaline protease from a recently identified P. minor. The enzyme was purified 2.7-fold with a 12.4 % recovery using Sephadex G-100 chromatography, DEAE-cellulose, and ammonium sulphate precipitation. The isolated enzyme has a specific activity of 473 U/mg. The purified protease had a molecular mass of 29 kDa, and just one band was seen, which matched the band obtained using SDS-PAGE. High thermostability was demonstrated by the enzymes, which had half-lives of 31.79 and 6.0 min (a 5.3-fold improvement), enthalpies of denaturation (ΔH°) of 119.53 and 119.35 KJ mol-1, entropies of denaturation (ΔS°) of 32.96 and 41.11 J/mol·K, and free energies of denaturation (ΔG°) of 108.87 and 105.58 KJ mol-1 for the protease enzyme. Studies on the folding and stability of alkaline proteases are important since their use in biotechnology requires that they operate in settings of extreme pH and temperature. According to the kinetic and thermodynamic properties, the protease produced by P. minor is superior to that produced by other sources and previously described plants, and it might find utility in a variety of industrial fields.


Assuntos
Phalaris , Endopeptidases , Temperatura , Peptídeo Hidrolases/metabolismo , Sementes/metabolismo , Concentração de Íons de Hidrogênio , Estabilidade Enzimática , Cinética
18.
Int J Biol Macromol ; 242(Pt 2): 124809, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37178877

RESUMO

Herein, we described for the first time, an efficient biogenic synthesis of APTs-AgNPs using acid protease from Melilotus indicus leaf extract. The acid protease (APTs) has an essential role in the stabilization, reduction, and capping of APTs-AgNPs. The crystalline nature, size, and surface morphology of APTs-AgNPs were examined using different techniques such as XRD, UV, FTIR, SEM, EDS, HRTEM, and DLS analysis. The generated APTs-AgNPs demonstrated notable performance as dual functionality (photocatalyst and antibacterial disinfection). By destroying 91 % of methylene blue (MB) in <90 min of exposure, APTs-AgNPs demonstrated remarkable photocatalytic activity. APTs-AgNPs also showed remarkable stability as a photocatalyst after five test cycles. Furthermore, the APTs-AgNPs was found to be a potent antibacterial agent with inhibition zones of 30(±0.5 mm), 27(±0.4 mm), 16(±0.1 mm), and 19(±0.7 mm) against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, respectively, under both light and dark conditions. Furthermore, APTs-AgNPs effectively scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, demonstrating their potent antioxidant activity. The outcomes of this study thus demonstrates the dual functionality of APTs-AgNPs produced using the biogenic approach method as a photocatalyst and an antibacterial agent for effective microbial and environmental control.


Assuntos
Nanopartículas Metálicas , Peptídeo Hidrolases , Peptídeo Hidrolases/farmacologia , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologia , Antibacterianos/química , Endopeptidases/farmacologia , Escherichia coli , Testes de Sensibilidade Microbiana
19.
Plants (Basel) ; 12(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37375867

RESUMO

The growth and productivity of wheat crops depend on the availability of essential nutrients such as zinc (Zn) and potassium (K2O), which play critical roles in the plant's physiological and biochemical processes. This study aimed to investigate the synergizing effect of zinc and potassium fertilizers on uptake of both the nutrients, growth, yield, and quality of the Hashim-08 cultivar and local landrace, during the 2019-2020 growing season in Dera Ismail Khan, Pakistan. The experiment was designed using a split plot pattern in a randomized complete pattern, with main plots for the wheat cultivars and subplots for the fertilizer treatments. Results indicated that both cultivars responded positively to the fertilizer treatments, with the local landrace exhibiting maximum plant height and biological yield, and improved Hashim-08, showing increased agronomic parameters, including the number of tillers and grains and spike length. Application of Zn and K2O fertilizers significantly enhanced agronomic parameters, such as the number of grains per plant, spike length, thousand-grain weight, grain yield, harvest index, Zn uptake of grain, dry gluten content, and grain moisture content, while crude protein and grain potassium remained relatively unchanged. The soil's Zn and K content dynamics were found to vary among treatments. In conclusion, the combined application of Zn and K2O fertilizers proved beneficial in improving the growth, yield, and quality of wheat crops, with the local landrace exhibiting lower grain yield but greater Zn uptake through fertilizer application. The study's findings highlight that the local landrace showed good response to the growth and qualitative parameter when compared with the Hashim-08 cultivar. Additionally, the combined application of Zn and K showed a positive relation in terms of nutrient uptake and soil Zn and K content.

20.
ACS Omega ; 8(43): 40128-40139, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37929083

RESUMO

Biochar derived from plant biomass has great potential for the decontamination of aqueous media. It is the need of the hour to test biochar derived from economical, easily available, and novel materials. In this regard, the present study provides insight into the sorption of two heavy metals, i.e., cadmium (Cd) and nickel (Ni), using native Arachis hypogaea and its biochar prepared through pyrolysis. The effect of different factors, including interaction time, initial concentration of adsorbate, and temperature, as well as sorbent dosage, was studied on the sorption of Cd and Ni through a batch experiment. Characterization of the native biowaste and prepared biochar for its surface morphology and functional group identification was executed using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Results revealed the presence of different functional groups such as -OH on the surface of the adsorbent, which plays an important role in metal attachment. SEM reveals the irregular surface morphology of the adsorbent, which makes it easy for metal attachment. Thermogravimetric analysis shows the stability of A. hypogaea biochar up to 380 °C as compared with native adsorbent. The adsorption efficacy of A. hypogaea was found to be higher than that of native A. hypogaea for both metals. The best adsorption of Cd (94.5%) on biochar was observed at a concentration of 40 ppm, an adsorbent dosage of 2 g, a contact time of 100 min, and a temperature of 50 °C. While the optimum conditions for adsorption of Ni on biochar (97.2% adsorption) were reported at a contact time of 100 min, adsorbent dosage of 2.5 g, initial concentration of 60 ppm, and temperature of 50 °C. Results revealed that biochar offers better adsorption of metal ions as compared with raw samples at low concentrations. Isothermal studies show the adsorption mechanism as physical adsorption, and the negative value of Gibb's free energy confirms the spontaneous nature of the adsorption reaction. An increase in entropy value favors the adsorption process. Results revealed that the sorbent was a decent alternative to eliminate metal ions from the solution instead of costly adsorbents.

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