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1.
Chemosphere ; 322: 138219, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36828108

RESUMEN

Decorating nanomaterials on graphene oxide (GO) can enhance its adsorption capacity and removal efficiency of water pollutants. In this study, for the first time, nano-sized polylactic acid (PLA) has been successfully decorated on the surface of GO through a facile synthesis approach. The adsorptive efficiency of GO-PLA for removing methylene blue (MB) and tetracycline (TC) from an aqueous solution was examined. The characterization confirmed the successful decoration of PLA on GO nanosheets with the nano size of PLA. It was hypothesized that the PLA was decorated on the surface of GO through covalent bonding between oxygen-containing functional groups and lactide molecules. The optimum adsorption parameters determined were at the adsorbent dose of 0.5 g L-1, pH 4, contact time of 120 min, and temperature of 318 K. The pseudo-second-order kinetic model described the contaminants' adsorption behaviour, and the intraparticle diffusion model revealed that both surface adsorption and intraparticle diffusion controlled the adsorption process. Langmuir isotherm model best described the adsorption behaviour of the pollutants on GO-PLA and demonstrated the maximum monolayer uptake capacities of MB (332.5 mg g-1) and TC (223.7 mg g-1). The adsorption results indicated that the uptake capacities of GO-PLA in comparison to GO have increased by approximately 70% and 110% for MB and TC, respectively. These observations reflect the remarkable role of nano-sized PLA that enhanced the adsorption capacity due to its additional functional group and larger surface area.


Asunto(s)
Grafito , Contaminantes Químicos del Agua , Azul de Metileno/química , Adsorción , Tetraciclina/química , Antibacterianos/química , Poliésteres , Grafito/química , Contaminantes Químicos del Agua/química , Cinética
2.
RSC Adv ; 13(8): 5013-5026, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36777948

RESUMEN

For the last several decades, semiconducting materials and nanocomposites have received a lot of interest in generating highly efficient photocatalysts to destroy organic pollutants and eradicate bacteria. This study uses a simple deposition and precipitation approach at ambient temperature to create a unique and efficient AgI-CdO heterojunction. DRS, IR, SEM, EDS, XRD, EIS, and TEM were utilized to identify the material. SEM and TEM investigation depict the completely spherical, hexagonal forms and zigzag cubes for synthesized AgI-CdO. The EDX spectra reveal the presence of Ag, I, Cd, and O elements without impurity peaks showing that the prepared samples are highly pure. The activity of the synthesized materials was tested by degrading two different chromophoric dyes and a drug derivative (paracetamol) in an aqueous suspension under visible light. In addition, the activity of the most active catalyst was compared with Degussa P25, Fenton's reagent, and under sunlight for degradation of MB and RhB under similar conditions. Photolysis of paracetamol was also looked at using HPLC to identify intermediates formed in the photo-oxidation process. In addition, antibacterial activity was also investigated with the synthesized CdO-AgI nanocomposite in vitro against human pathogenic bacterial strains and compared with that of pure materials like AgI and standard ampicillin. The results showed excellent activity with the composite material, which could be due to the higher surface areas and the interactions between AgI and CdO nanoparticles. Quenching investigations revealed O2˙- and holes are principal reactive species. A viable photocatalytic degradation mechanism for organic pollutant elimination over the AgI-CdO nanocomposite has been sketched out based on the obtained results.

3.
Cureus ; 14(11): e31019, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36475157

RESUMEN

Congenital insensitivity to pain with anhidrosis, or hereditary sensory and autonomic neuropathy (HSAN) type IV, is an exceedingly rare neurogenetic disorder. Reported causes are homozygous or compound heterozygous loss-of-function mutations in the neurotrophic tyrosine receptor kinase 1 gene (NTRK1). Characteristically, patients with this disorder exhibit a complete diminution of pain and temperature sensations over the body disrupted sweat gland functioning, and variable degrees of sensation and cognitive impairments. We hereby present the clinical and neurophysiologic features of a 15-month-old boy with a homozygous frameshift mutation in c.1860_186insT. (p.Pro621Serfs*12) in the NRTK1 gene, consistent with the diagnosis of congenital insensitivity to pain with anhidrosis.

4.
Heliyon ; 8(9): e10385, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36060472

RESUMEN

This study reviews Islamic FinTech research development from 2017 to 2022. The study adopts a hybrid approach combining bibliometric and content analysis to reveal the current research trend of Islamic FinTech research. Using the Scopus database, we retrieve 85 documents and analyze them using RStudio and VOSviewer. The content analysis categorizes the research output in Islamic FinTech into four distinct streams. The study finds potential for cointegrating FinTech into Islamic finance to benefit the unbanked and small-medium-size businesses, the adoption of FinTech in Islamic finance will also help the government improve financial inclusion, conquer financial crises, such as COVID-19, and achieve SDGs for a sustainable nation. However, the lack of legal regulation and the lower financial literacy becomes the primary obstacle to the development of FinTech in Islamic finance.

5.
Ann Oper Res ; : 1-37, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36042920

RESUMEN

The COVID-19 pandemic has inflicted the global economy and caused substantial financial losses. The energy sector was heavily affected and resulted in energy prices massively tumbling. The Russian invasion of Ukraine has fueled the energy maker more volatile. In such uncertain contexts, an Early Warning System (EWS) would efficiently contribute to stabilizing market swings. It will leverage the ability to control operating costs and pave the way for smooth economic recovery. Within this framework, we deploy Machine Learning (ML) models to forecast energy equity prices by employing uncertainty indices as a proxy for predicting energy market volatility. We empirically examine the comparative effectiveness of prevalent ML models and conventional approaches (regression) to forecast the energy equity prices by utilizing the daily data from 1/6/2011 to 18/1/2022 for four US uncertainty and eight energy equity indices. Results show that the Nonlinear Autoregressive with External (Exogenous) parameters (NARX) of Neural Networks (NN) scored significantly better accuracy than all other (25) ML models and conventional approaches. The study outcomes are beneficial for policymakers, governments, market regulators, investors, hedge and mutual funds, and corporations. They improve stakeholders' resilience to exogenous shocks, blaze the recovery path, and provide evidence-based for assets allocation strategies.

6.
Saudi J Biol Sci ; 29(8): 103346, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35784613

RESUMEN

The present study examined the phytochemical composition, antioxidant, antimicrobial properties, and molecular docking of different solvents extracts (methanol and water) of two medicinal plants, namely, Capparis spinosa L (CS) and Rumex nervosus (RN). Phytochemical analysis showed that total phenol, flavonoids, alkaloids, and vitamin C were significantly (P ≤ 0.05) higher in the methanolic extract of both plants than in other solvents. However, tannin content was significantly (P ≤ 0.05) high in the water extract for both plants. Chloroform and acetone extracts were significantly lower in phytochemicals than other solvents, therefore excluded in this study. GC-MS analysis showed one dominant compound in CS (isopropyl isothiocyanate) and two in RN (pyrogallol and palmitic acid). The antioxidant methods applied (DPPH, ABTS, ß-Carotene/linoleic acid assay, and reducing the power) showed that the methanolic extract of CS exerted higher activity in methanolic extract but lower than that of BHA standard. The methanolic extract of both plants inhibited the bacterial pathogens when a minimum inhibitory concentration (MIC) method was applied, compared to water extract with RN-methanolic extract had a lower inhibition concentration than CS-methanolic extract. The molecular interactions study revealed that the palmitic acid and pyrogallol interacted with the receptors' active site. This work concluded that CS and RN showed a remarkable antioxidant and antibacterial effect with the high antimicrobial activity of RN extract.

7.
Sci Prog ; 105(2): 368504221102751, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35619568

RESUMEN

This study tested the protective effect of Rumex nervous (R. nervosus) methanol extract against streptozotocin (STZ)-mediated type 1 diabetes mellitus (T1DM)-induced nephropathy in rats and examined if this protection involves activating the nuclear factor erythroid 2 related factor-2 (Nrf2). Rats were divided into control, R. nervous (300 mg), STZ (T1DM), STZ + R. nervosus (100, 200, or 300 mg/kg), and STZ + R. nervosus (300 mg/kg) + brusatol (an Nrf2 inhibitor). With no effect on fasting glucose and insulin levels, R. nervosus methanol extract preserved kidney histological structure and alterations kidney function markers (e.g. albumin, creatinine, and urine volume) in the STZ-diabetic rats. R. nervosus also reduced levels of reactive oxygen species (ROS), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), and interleukine-6 (IL-6), nuclear levels of the nuclear factor kappa beta (NF-κB), and mRNA of caspase-3 and Bax in the kidneys of these diabetic rats. Concomitantly, it stimulated renal mRNA levels of Bcl2 and Nrf2, cytoplasmic and nuclear levels of Nrf2, and levels of glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). All these effects were dose-dependent, with the maximum effect seen with the 300 mg/kg dose, all prevented by brusatol. Also, these effects occurred without any alteration in the transcription of the Kelch-like ECH-associated protein 1 (keap-1). Similar effects on levels of GSH, SOD, CAT, and NF-κB, as well as expression of Nrf2, were also observed in the kidney of control + R. nervous-treated rats. In conclusion, R. nervosus prevents diabetic nephropathy in rats by upregulating and activating Nrf2.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Nefropatías Diabéticas , Extractos Vegetales , Rumex , Animales , Ratas , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Nefropatías Diabéticas/tratamiento farmacológico , Glutatión , Metanol , Factor 2 Relacionado con NF-E2/genética , FN-kappa B/genética , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , ARN Mensajero , Rumex/química , Estreptozocina/toxicidad , Superóxido Dismutasa
8.
Saudi J Biol Sci ; 29(2): 963-969, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35197764

RESUMEN

The pectinase enzymes are involved in several industrial applications, and industrial waste is one of the largest environmental pollutants, so this study aims to Endo-polygalacturonase (endo-PG) producing using Aspergillus niger AUMC 4156, Penicillium oxalicum AUMC 4153 and P. variotii AUMC 4149 by using some agro-industrial wastes (dried orange peel and sugar beet pulp) as a sole raw carbon source for degradation these waste in the process of urban wastes disposal. The fermentation process was carried out as a submerged culture technique under both shaken and static culture conditions. A. niger AUMC 4156 was the most promising producer of endo-PG under static conditions while P. oxalicum AUMC 4153 was the highest producer of endo-PG under shaken conditions. Sugar beet pulp proved to be the most preferable to orange peel as the only source of carbon in both shaken and static cultures. The medium that encompassing orange peel as a single carbon source afforded the highest protein content with all tested fungal strains in stirred and static cultures in comparison with sugar beet pulp. The highest activity of endo-polygalacuronase that produced using A. niger AUMC 4156 and P. oxalicum AUMC 4153 was achieved by using sugar beet pulp at 3% concentration under static cultures, meanwhile maximal enzyme activity produced by both fungal strains required 2% sugar beet pulp under shaken cultures. Sugar beet pulp showed promised potential as a good inducer for endo-polygalacturoase production, and enzymes production depended on fungal strains, culture medium, and submerged fermentation conditions.

9.
Life (Basel) ; 12(2)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35207571

RESUMEN

Pectinase enzymes are important industrial enzymes having considerable applications in several industries, especially in food processing. Pectinases contribute 25% of global food enzyme sales. Therefore, the demand for a commercial enzyme with desirable characteristics and low production costs has become one of the great targets. Hence, this study aims to produce exo-polygalacturonase (exo-PG) using local fungal isolate Penicillium oxalicum AUMC 4153 by utilizing sugar beet manufacturing waste (sugar beet pulp) as a sole raw carbon source under shaken submerged fermentation, which is purified and characterized to optimize enzyme biochemical properties for industrial application. The purity of the obtained exo-PG was increased by about 28-fold, and the final enzyme yield was 57%. The partially purified enzyme was active at a broad range of temperatures (30-60 °C). The optimum temperature and pH for the purified exo-PG activity were 50 °C and pH 5. The enzyme was stable at a range of pH 3 to 6 and temperature 30-50 °C for 210 min. The values for Km and Vmax were 0.67 mg/mL, with polygalacturonic acid as substrate and 6.13 µmole galacturonic acid/min/mg protein, respectively. It can be concluded that purified exo-PG production by P. oxalicum grown on sugar beet waste is a promising effective method for useful applications.

10.
Saudi J Biol Sci ; 29(1): 640-649, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35002461

RESUMEN

Shrimp is a prevalent food in the Arabian Gulf that is known for its good sensory properties and high nutritional value. The aim of the present work was to assess the effects of diverse processing methods on the nutritional composition of shrimp and the antioxidant activity of shrimp powder. Shrimp (Penaeus semisulcatus) flesh was treated using four processes (salting, frying, grilling, and boiling), following which its macronutrient content, fatty acid profile, vitamins and mineral contents were measured. Also, the antioxidant activity of all shrimp powder extracts was assessed using the 2, 2 diphenyl 1 picrylhydrazyl (DPPH), linoleic acid oxidation inhibition, and reducing power methods. The results revealed that the fresh and processed shrimp flesh had significant nutritional value and the fresh and treated shrimp powders have high antioxidant activity, but the cooking processes have significant effects on the nutritional value and antioxidant activity of shrimp flesh. These effects were greater significantly in grilled shrimp followed by boiled shrimp and then fried shrimp. It is concluded that the high nutritional value and antioxidant activity of shrimp flesh make it an important food for nutritional health promotion for the community.

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