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1.
Environ Pollut ; 342: 123076, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38048873

RESUMEN

Most bacterial disinfectants contain high levels of extremely toxic and environmental hazardous chemicals, which pose a significant threat to the ecosystem. Semiconductor photocatalysis exhibits attractive prospects as an emerging greener technology for waste water disinfection. However, the fast recombination of charge carriers limits its practical application. Herein, self-assembled polymeric feather-like g-C3N4 (GCN) nanosheets modified with ferromagnetic CuFe2O4 (CFO) nanospheres were successfully applied as a reusable visible light photocatalytic disinfectant. As expected, the g-C3N4/CuFe2O4 (GCF) nanohybrid displayed superior photocatalytic inactivation efficiency of 0.157log within 120 min towards Escherichia coli DH5α (E. coli) compared with pristine GCN and CFO. The characterization results revealed the synergistic heterostructure interfaces, high surface area, and the transformative self-assembly of GCN to feather-like structure providing a rich active site for improved charge separation efficiency, and wide spectral response, therefore the superior performance of GCF. The radical trapping assay proclaimed that both O2•- and •OH radical played major role in the photocatalytic inactivation among the other reactive oxygen species (ROS). Furthermore, the chemical oxygen demand (COD), protein estimation, and DNA estimation assay results validated the cell damage caused by the photocatalyst. Besides that, GCN showed applicability in real-time wastewater samples with improved efficiency than in the saline solution. The excellent magnetic characteristics facilitated the recycling of the catalyst with insignificant leaching, magnetic induction, and distinguished separation. The results of this work signify the well-designed GCF as a high-performance and reusable photocatalyst for real-world pathogenic bacterial disinfection operations.


Asunto(s)
Desinfección , Aguas Residuales , Bacterias , Catálisis , Desinfectantes/farmacología , Desinfección/métodos , Ecosistema , Escherichia coli/fisiología , Luz
2.
Chemosphere ; 314: 137516, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36521743

RESUMEN

The study reports an innovative approach on sunlit driven heterostructure photocatalytic generation of H2O2 and removal of cefixime. In the present work, we have fabricated Mn/Mg doped CoFe2O4 modified CaCr2O4 decorated by Ag3PO4 quantum dots (Ag3PO4 QDs), a p-n-p nano heterojunction. The study promotes the photocatalytic production of H2O2 and self-Fenton photocatalytic degradation of cefixime. Egg white-assisted synthesis of Mn-doped CoFe2O4 causes the lattice oxygen defect, which enhances the photocatalytic activity. Lattice oxygen defect enable the adsorption of O2, which enable the conversion of •O2 in the valence band of CoFe2O4 for the endogenous production of H2O2. The higher in the surface area enhance the photocatalytic activity under visible light irradiation. Mn-CoFe2O4-CaCr2O4-Ag3PO4 QDs enables the complete photocatalytic degradation of cefixime (99.9%) and the complete removal was determined by total organic carbon (TOC) removal and it was around 99.4%. Meanwhile the photocatalytic degradation pathway of cefixime was determined by LC-MS/MS. Reusability of the nano heterojunction was determined by six cycle test, and the reusability of the nano heterojunction was 99.8%. Further, the toxicity of the nanomaterial was studied in maize plant and the results shows that the nanoheterojunction enhances the maize growth. The study systematically reveals the robust activity of nano heterojunction for sustainable water treatment.


Asunto(s)
Peróxido de Hidrógeno , Puntos Cuánticos , Cefixima , Cromatografía Liquida , Espectrometría de Masas en Tándem , Puntos Cuánticos/química
3.
Chemosphere ; 313: 137286, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36403816

RESUMEN

Photocatalytic induction of electron/hole recombination, surface property and light response ability effectively enhance the photocatalytic activity of nanomaterial. In this work, the effective charge carrier separating Sn/Mn-ZnFe2O4-CdFe2O4-Ag3PO4 Quantum dots (M/SZFO-CFO-AP QDs) was fabricated for photocatalytic degradation of doxycycline (doxy) antibiotic. The result showed enhanced photocatalytic activity of doxy and the degradation efficiency of doxy was about 98.8% in short span of time. The calculated WH plot and urbach energy of prepared photocatalyst exhibited evidence for the prevalence of point defects and its contribution to efficient charge separation and transferability. The total organic carbon (TOC) removal was found to be 98.9%, which depicts the complete mineralization of doxy. The synergetic charge transfer of n-p-n heterojunction enables the effective removal of doxy under visible light irradiation. Further, the genotoxicity study was determined by interacting the SZFO-CFO-AP QDs with Allium Cepa. The results depict that SZFO-CFO-AP QDs show lower toxicity level and there were no trace of defective mitotic phases and micro nuclei. Further, the progression and development of bean plant was determined after treating with prepared nanomaterials and the result showed the enhanced growth in SZFO-CFO-AP QDs treated bean plant compared to the counterparts. Therefore, the prepared SZFO-CFO-AP QDs was can be used as an environmental friendly photocatalyst for effective treatment of antibiotic present in the water bodies.


Asunto(s)
Nanoestructuras , Luz Solar , Fotólisis , Doxiciclina/farmacología , Cebollas , Catálisis , Antibacterianos/toxicidad , Nanoestructuras/toxicidad
4.
J Environ Manage ; 319: 115674, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35868190

RESUMEN

In this study, 3D C2S3 (CS) and 2D Bi2S3 (BS) modified NiCr2O4 nanocomposite (NCO-BS-CS NCs) was prepared by sonochemical assisted co-precipitation method for the enhanced photocatalytic activity. Here, NCO-BS-CS NCs showed band gap energy of 2.23 eV and the PL intensity of NCO-BS-CS NCs was lower than NCO, BS, and CS NPs. Thus, the results indicate the fabricated NCO-BS-CS NCs enhance the charge segregation and lower in recombination rate. NCO-BS-CS NCs showed enhanced photodegradation of methyl orange (MO) (95%) and congo red (CR) (99.7%) respectively. The total organic compound (TOC) analysis shows the complete mineralization of about 91 and 98% for MO and CR respectively. Furthermore, the Fukui function was used for the prediction of reactive sites in the photodegradation pathway of MO and CR by NCs. ECOSAR program was done to determine the toxicity of the intermediate and the results conclude that the degraded product shows nontoxic to the environmental organism (fish, daphnia, and algae). Thus, the fabricated NCO-BS-CS NCs can be used for the remediation of toxic organic pollutants from the waste water by photocatalytic degradation.


Asunto(s)
Contaminantes Ambientales , Nanocompuestos , Contaminantes Químicos del Agua , Animales , Catálisis , Dominio Catalítico , Rojo Congo/química , Contaminantes Ambientales/análisis , Luz , Nanocompuestos/química , Nanocompuestos/toxicidad , Esqueleto/química , Contaminantes Químicos del Agua/química
5.
Chemosphere ; 304: 135225, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35697102

RESUMEN

Biosynthesis of nanomaterials using plant extract makes them attractive in the field of photocatalysis as they are environmental friendly. The current study focused on the biosynthesis of ZnO/NiCo2S4 QDs (NCs) using Punica granatum fruit peel extract as the reducing agent. The nanomaterials were characterized with XRD, FTIR, Raman, SEM, TEM, UV-vis DRS, BET, PL, EIS, and ESR analysis and were used for photocatalytic degradation of doxycycline (DOX) and ciprofloxacin (CIP). The bandgap of ZnO is 3.2 eV, and the decoration of NiCo2S4 QDs aids in narrowing the bandgap (2.8 eV), making the NCs visible light active. The fabricated NCs achieved 99 and 89% degradation of DOX and CIP respectively. The photocatalytic efficiency of ZnO/NiCo2S4 QDs was much higher compared to individual ZnO and NiCo2S4 QDs. The half-life period of DOX and CIP were evaluated to be 58 and 152 min respectively. The percentage of TOC removal in the photodegraded product of DOX and CIP was estimated to be 99 and 89% respectively, indicating the mineralization of the compounds. The enhanced photocatalytic efficiency of the NCs was attributed to the narrowed visible light active bandgap, synergistic charge transfer across the interface, and lower charge recombination. The intermediates formed during the photocatalytic degradation of DOX and CIP were analyzed using GC-MS/MS analysis, and the photodegradation pathway was elucidated. Also, the toxicity of the intermediates was computationally analyzed using ECOSAR software. The fabricated ZnO/NiCo2S4 QDs have excellent stability and reusability, confirmed by XRD and XPS analysis. The reusable efficiency of the NCs for the photocatalytic degradation of DOX and CIP were 98.93, and 99.4% respectively. Thus, the biologically fabricated NCs are shown to be an excellent photocatalyst and have wide applications in environmental remediation.


Asunto(s)
Granada (Fruta) , Óxido de Zinc , Ciprofloxacina , Doxiciclina , Electrones , Frutas , Luz , Extractos Vegetales , Espectrometría de Masas en Tándem
6.
Chemosphere ; 303(Pt 1): 134963, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35588875

RESUMEN

Pharmaceutical pollutant in the environmental water bodies has become a major concern, which causes adverse effect to aquatic entities. This study provides an incisive insight on the photocatalytic degradation of ciprofloxacin (CIP) and the development of rationally engineered g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite for boosted photocatalytic performance under visible light irradiation. The g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite was synthesized via ultrasonication-assisted hydrothermal method. The characterization of the as-prepared material was evaluated by XPS, SEM, HR-TEM, PL, FT-IR, EIS, ESR, XRD, BET, and UV-Vis DRS techniques. Furthermore, the effect of catalytic dosage, drug dosage, and pH changes was explored, where g-C3N4-NiCo2O4-Zn0.3Fe2·7O4-10% unveiled excellent visible light photo-Fenton degradation of 92% for CIP at 140 min. The hydroxyl radicals (OH.) served as the predominant radical species on the photodegradation of CIP, which was confirmed by performing a radical scavenging test. Furthermore, the degradation efficiency was determined by six consecutive cycle tests, where the nanomaterial exhibited excellent stability with 98.5% reusable efficiency. The degradation of CIP was further scrutinized by GC-MS analysis, where the degraded intermediate products and the possible pathway were elucidated. The degraded product toxicity was determined by ECOSAR program, where the degraded products haven't exhibited any considerable toxic effects. In addition, the genotoxicity of the nanomaterial was determined by treating them with root tips of A. cepa, where it was found to be non-toxic. Here, the prepared g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite (CNZ NCs) shows eco-friendly and excellent photo-Fenton activity for environmental applications.


Asunto(s)
Ciprofloxacina , Cebollas , Catálisis , Ciprofloxacina/toxicidad , Daño del ADN , Luz , Espectroscopía Infrarroja por Transformada de Fourier , Zinc
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 279: 121330, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35605418

RESUMEN

L-cystine (L-cys) functionalized plasmonic silver nanomaterial (Ag NPs) was fabricated toward the selective and sensitive detection of paracetamol and cadmium. The prepared L-cys-Ag nanoparticles (NPs) were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD) and fourier transform infrared spectroscopy (FTIR) analyses. SEM imaging show that Ag NPs was decorated on the surface of L-cysteine 3D cubic nanosheet. L-cys-Ag NPs showed selective and sensitive detection towards paracetamol and cadmium. The interference study confirms that the presence of other metal ions didn't inhibit the detection of cadmium by L-cys-Ag NPs. The limit of detection of paracetamol and cadmium by L-cys-Ag NPs was calculated to be 1.2 and 2.82 nM respectively. In addition, the real sample detection of paracetamol on blood serum and urine, and cadmium on STP were performed and the recovery percentage was above 97%. Further, the real sample analysis was performed in tap and drinking water and the recovery percentage was more than 98%. The analytic logic gate on the multicolour detection of cadmium and paracetamol was performed for the semi-quantitative monitoring of paracetamol and cadmium by L-cys-Ag NPs. The developed L-cys-Ag NPs were found to be an effective tool for the monitoring of cadmium in environmental water bodies and paracetamol in blood and urine.


Asunto(s)
Nanopartículas del Metal , Plata , Acetaminofén , Cadmio , Cistina , Nanopartículas del Metal/química , Plata/química , Espectroscopía Infrarroja por Transformada de Fourier
8.
Chemosphere ; 297: 134130, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35257704

RESUMEN

The present study focused on the photocatalytic degradation of 5-Flurouracil (FU), carvedilol (Car), para-chlorophenol (PCP) and methimazole (Met) under visible light irradiation by MnWO4/Ag2WO4 (MWO/AWO) nanohybrid. Here, MWO/AWO nanohybrid was characterized by XRD, TEM, EDS, XPS, ESR, EIS, BET and DRS. The band gap energy of the MWO/AWO nanohybrid was found to be 2.75 eV, which enables effective photocatalytic activity of nanohybrid under visible light. The photocatalytic degradation of various PhACs such as Fu, Car, PCP and Met was found to be 98.8, 100, 98 and 98.1% respectively. The degradation efficiency of the MWO/AWO nanohybrid on various PhACs was higher than the pure MWO and AWO nanoparticle. The effective formation of OH• and •O2 by MWO/AWO nanohybrid played an important role in degradation of PhACs and it was determined by radical scavenging experiment. Further, the intermediates formed during the photocatalytic process were analyzed by GC-MS/MS to elucidate the photodegradation pathway and the results reveal the complete mineralization of the PhACs. The toxicity of the degraded product was performed against on Bacillus subtilis and Escherichia coli where it shows that the nanohybrid possesses high relative growth inhibition than AWO and MWO nanoparticles. In addition, the genotoxicity of the nanohybrid against Allium cepa was performed and it exhibited lower toxicity. The synthesized nanohybrid proves to be an excellent photocatalyst with good stability, reusability, eco-friendly, and cost-effective material for implementation in practical applications.


Asunto(s)
Clorofenoles , Nanotubos , Purificación del Agua , Carvedilol , Catálisis , Luz , Metimazol , Fotólisis , Espectrometría de Masas en Tándem
9.
J Environ Manage ; 308: 114614, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35121463

RESUMEN

In this study, 3D BiOI nanoparticle (BOI NPs) modified MgCr2O4 nanoparticle (MCO NPs) was fabricated by simple sonochemical and coprecipitation method for the enhanced photocatalytic activity. The morphological structure of the MgCr2O4-BiOI nanocomposite (MCO-BOI NCs) was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectroscopy (DRS), electron impedance spectroscopy (EIS) and photo luminescence (PL). The lower in the PL intensity and small arc in EIS for NCs shows the effective charge separation and lower in rate of recombination of charge carriers in NCs than the pure MCO and BOI NPs. The degradation efficiency of Rhodamine B (RhB) and malachite green (MG) by MCO-BOI NCs was found to be 99.5% and 98.2% receptivity. In addition, the photocatalytic degradation of RhB and MG was studied under various environmental parameters (different pH, varying the concentration of NCs and dyes) and response surface (RSM) plot was performed. The complete mineralization of RhB and MG by MCO-BOI NCs was determined by TOC. In addition, the photocatalytic degradation pathway was elucidated based on GC-MS results and Fukui function. In addition, the toxicity of intermediate formed during the degradation of RhB and MG was predicted by ECOSAR. The present work highlights the application of MCO-BOI NCs in environmental remediation for toxic pollutant removal.


Asunto(s)
Nanosferas , Catálisis , Dominio Catalítico , Flores , Rodaminas , Colorantes de Rosanilina
10.
Mar Pollut Bull ; 175: 113287, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35114544

RESUMEN

In this study, the physiology of symbiotic 'peacock-tail' shrimp Ancylocaris brevicarpalis and its host 'Haddon's carpet' sea anemone Stichodactyla haddoni were tested under lowered pH (7.7) and control (8.1) conditions. The biochemical responses such as digestive enzyme (AP), organic acids (lactate and succinate), oxidative damages (MDA), antioxidants metabolites/enzymes (ASC, GSH, SOD, CAT, APX, GPX, GR, POX, and PHOX), and detoxification enzyme (GST) were measured. The AP showed insignificantly reduced values in both the organisms in lowered pH conditions compared to control indicating the effect of abiotic stress. The hierarchical clustering analysis indicated low MDA in sea anemone can be explained by higher POX, APX, GR, ASC, and GSH levels compared to shrimps. However, the detoxification enzyme GST showed less activity in sea anemones compared to shrimps. The results suggest that A. brevicarpalis and sea anemone S. haddoni may have deleterious effects when exposed to short-term acidification stress.


Asunto(s)
Anémonas de Mar , Animales , Antioxidantes , Concentración de Iones de Hidrógeno , Océanos y Mares , Agua de Mar , Simbiosis
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120793, 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35007902

RESUMEN

Novel Ag@Ni nanosphere decorated with CdS NPs (Ag@Ni-CdS NCs) was synthesized by one step chemical synthesis method. The fabricated NCs were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), fourier transfer infra-red spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), zeta sizer and particle size analyzer. TEM and XRD confirmed the Ag in core and Ni in shell for the effective formation of Ag@Ni core shell nanosphere. EDAX and XPS spectra of NCs confirms the formation of Ag@Ni-CdS NCs. Zeta potential and particle size of the NCs was found to be 29.5 ± 1.5 mV and 24 ± 1 nm respectively. The complete loss in the peak intensity of Ag@Ni-CdS NCs (localized surface plasmon resonance (LSPR)) at ∼410 nm in presence of S2- ions was observed which indicates its selective detection towards S2- ions. The sulfide ion sensing by Ag@Ni-CdS NCs was due to the successive oxidation of Ag results in the formulation of Ag2+ ions in the system, which causes the diminishing of LSPR band of NCs. The limit of detection (LOD) of S2- ions by Ag@Ni-CdS NCs was calculated to be of 2.66 nM. The combination of CdS NPs with core-shell Ag@Ni nanosphere guides a promising strategy for S2- ions detection from environmental polluted samples.


Asunto(s)
Nanosferas , Sulfuros , Espectroscopía de Fotoelectrones , Resonancia por Plasmón de Superficie , Agua
12.
Plants (Basel) ; 10(11)2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34834749

RESUMEN

Molybdenum ions (Mo) can improve plants' nutritional value primarily by enhancing nitrogenous metabolism. In this study, the comparative effects of seed priming using Mo were evaluated among sproutings of Canavalia species/cultivars, including Canavalia ensiformis var. gladiata (CA1), Canavalia ensiformis var. truncata Ricker (CA2), and Canavalia gladiata var. alba Hisauc (CA3). Mo impacts on growth, metabolism (e.g., nitrogen and phenolic metabolism, pigment and total nutrient profiles), and biological activities were assayed. Principal component analysis (PCA) was used to correlate Mo-mediated impacts. The results showed that Mo induced photosynthetic pigments that resulted in an improvement in growth and increased biomass. The N content was increased 0.3-fold in CA3 and 0.2-fold in CA1 and CA2. Enhanced nitrogen metabolism by Mo provided the precursors for amino acids, protein, and lipid biosynthesis. At the secondary metabolic level, phenolic metabolism-related precursors and enzyme activities were also differentially increased in Canavalia species/cultivars. The observed increase in metabolism resulted in the enhancement of the antioxidant (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP)) and antidiabetic potential (Glycemic index (GI) and inhibition activity of α-amylase, and α-glucosidase) of species. The antioxidant activity increased 20% in CA3, 14% in CA1, and 8% in CA2. Furthermore, PCA showed significant variations not only between Mo-treated and untreated samples but also among Canavalia species. Overall, this study indicated that the sprouts of Canavalia species have tremendous potential for commercial usage due to their high nutritive value, which can be enhanced further with Mo treatment to accomplish the demand for nutritious feed.

13.
Plants (Basel) ; 10(4)2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33916328

RESUMEN

Understanding salt tolerance in tomato (Solanum lycopersicum L.) landraces will facilitate their use in genetic improvement. The study assessed the morpho-physiological variability of Hail tomato landraces in response to different salinity levels at seedling stages and recommended a tomato salt-tolerant landrace for future breeding programs. Three tomato landraces, Hail 548, Hail 747, and Hail 1072 were tested under three salinity levels: 75, 150, and 300 mM NaCl. Salinity stress reduced shoots' fresh and dry weight by 71% and 72%, and roots were 86.5% and 78.6%, respectively. There was 22% reduced chlorophyll content, carotene content by 18.6%, and anthocyanin by 41.1%. Proline content increased for stressed treatments. The 300 mM NaCl treatment recorded the most proline content increases (67.37 mg/g fresh weight), with a percent increase in proline reaching 61.67% in Hail 747. Superoxide dismutase (SOD) activity decreased by 65% in Hail 548, while it relatively increased in Hail 747 and Hail 1072 treated with 300 mM NaCl. Catalase (CAT) activity was enhanced by salt stress in Hail 548 and recorded 7.6%, increasing at 75 and 5.1% at 300 mM NaCl. It revealed a reduction in malondialdehyde (MDA) at the 300 mM NaCl concentration in both Hail 548 and Hail 1072 landraces. Increasing salt concentrations showed a reduction in transpiration rate of 70.55%, 7.13% in stomatal conductance, and 72.34% in photosynthetic rate. K+/Na+ ratios decreased from 56% for 75 mM NaCl to 85% for 300 mM NaCl treatments in all genotypes. The response to salt stress in landraces involved some modifications in morphology, physiology, and metabolism. The landrace Hail 548 may have better protection against salt stress and observed protection against reactive oxygen species (ROS) by increasing enzymatic "antioxidants" activity under salt stress.

14.
Int J Mol Sci ; 21(7)2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32272790

RESUMEN

Sulfur (S) is an essential element for all forms of life. It is involved in numerous essential processes because S is considered as the primary source of one of the essential amino acids, methionine, which plays an important role in biological events. For the control and regulation of sulfate in a metabolic network through fluxomics, a non-invasive tool is highly desirable that opens the door to monitor the level of the sulfate in real time and space in living cells without fractionation of the cells or tissue. Here, we engineered a FRET (fluorescence resonance energy transfer) based sensor for sulfate, which is genetically-encoded and named as FLIP-SP (Fluorescent indicator protein for sulfate). The FLIP-SP can measure the level of the sulfate in live cells. This sensor was constructed by the fusion of fluorescent proteins at the N- and C-terminus of sulfate binding protein (sbp). The FLIP-SP is highly specific to sulfate, and showed pH stability. Real-time monitoring of the level of sulfate in prokaryotic and eukaryotic cells showed sensor bio-compatibility with living cells. We expect that this sulfate sensor offers a valuable strategy in the understanding of the regulation of the flux of sulfate in the metabolic network.


Asunto(s)
Sulfatos/metabolismo , Aminoácidos/metabolismo , Técnicas Biosensibles/métodos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Transferencia Resonante de Energía de Fluorescencia/métodos , Proteínas Luminiscentes/metabolismo , Metionina/metabolismo , Saccharomyces cerevisiae/metabolismo , Tiempo
15.
Antioxidants (Basel) ; 9(4)2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32244268

RESUMEN

(+)-Catechin is an important antioxidant of green tea (Camelia sinensis (L.) O. Kuntze). Catechin is known for its positive role in anticancerous activity, extracellular matrix degradation, cell death regulation, diabetes, and other related disorders. As a result of enormous interest in and great demand for catechin, its biosynthesis using metabolic engineering has become the subject of concentrated research with the aim of enhancing (+)-catechin production. Metabolic flux is an essential concept in the practice of metabolic engineering as it helps in the identification of the regulatory element of a biosynthetic pathway. In the present study, an attempt was made to analyze the metabolic flux of the (+)-catechin biosynthesis pathway in order to decipher the regulatory element of this pathway. Firstly, a genetically encoded fluorescence resonance energy transfer (FRET)-based nanosensor (FLIP-Cat, fluorescence indicator protein for (+)-catechin) was developed for real-time monitoring of (+)-catechin flux. In vitro characterization of the purified protein of the nanosensor showed that the nanosensor was pH stable and (+)-catechin specific. Its calculated Kd was 139 µM. The nanosensor also performed real-time monitoring of (+)-catechin in bacterial cells. In the second step of this study, an entire (+)-catechin biosynthesis pathway was constructed and expressed in E. coli in two sets of plasmid constructs: pET26b-PT7-rbs-PAL-PT7-rbs-4CL-PT7-rbs-CHS-PT7-rbs-CHI and pET26b-T7-rbs-F3H-PT7-rbs- DFR-PT7-rbs-LCR. The E. coli harboring the FLIP-Cat was transformed with these plasmid constructs. The metabolic flux analysis of (+)-catechin was carried out using the FLIP-Cat. The FLIP-Cat successfully monitored the flux of catechin after adding tyrosine, 4-coumaric acid, 4-coumaroyl CoA, naringenin chalcone, naringenin, dihydroquercetin, and leucocyanidin, individually, with the bacterial cells expressing the nanosensor as well as the genes of the (+)-catechin biosynthesis pathway. Dihydroflavonol reductase (DFR) was identified as the main regulatory element of the (+)-catechin biosynthesis pathway. Information about this regulatory element of the (+)-catechin biosynthesis pathway can be used for manipulating the (+)-catechin biosynthesis pathway using a metabolic engineering approach to enhance production of (+)-catechin.

16.
Saudi J Biol Sci ; 27(2): 682-688, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32210688

RESUMEN

In this study, phyto-constituents, anti-bacterial and anticancer activity of Azadirachta indica A. Juss and Melia azedarach Linn was analyzed. High Performance Liquid Chromatography (HPLC) and Thin Layer Chromatography (TLC) fingerprint profile of methanol extract of A. indica and M. azedarach was carried out. The present findings showed the presence of phytochemicals such as, steroids, alkaloids, phenols, flavonoids, saponins, tannins, anthraquinone and aminoacids in A. indica and M. azedarach extracts. HPLC profiling of methanolic extract of A. indica and M. azaderach revealed eleven and ten fractions of compounds were visualized in the form of peak. In TLC methanolic extract of A. indica was separated by eight distinct phenolic and three steroidal bands and M. azaderach showed sixteen distinct phenolic and three different steroidal bands. In antibacterial activity, Among the various extracts 50 µg/ml methanolic extracts of A. indica showed high activity against K. pneumoniae (14 mm) and M. azedarach showed high activity against S. aureus (15 mm). The results suggest that the crude methanolic extracts of A. indica and M. azedarach possess significant phytochemical properties compared to other extracts and hence the phytochemicals of M. azedarach and A. indica can be exploited for plant based anticancer and antimicrobial agents in the near future.

17.
Plants (Basel) ; 9(2)2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32074984

RESUMEN

An efficient protocol of plant regeneration through indirect organogenesis in Viola serpens was developed in the present study. Culture of leaf explants on MS (Murashige and Skoog) medium supplemented with 2.0 mg/L 6-benzyladenine and 0.13 mg/L 2,4-dichloro phenoxy acetic acid. Adventitious shoot formation was observed when calli were transferred on to MS medium containing 0.5 mg/L α-naphthalene acetic acid and 2.25 mg/L kinetin, which showed the maximum 86% shoot regeneration frequency. The highest root frequency (80.92%) with the 5.6 roots per explant and 1.87 cm root length was observed on MS medium supplemented with 2 mg/L indole-3-butyric acid. The plantlets were transferred to the mixture of sand, coffee husk and soil in the ratio of 1:2:1 in a pot, and placed under 80% shade net for one month. It was then transferred to 30% shade net for another one month, prior to transplantation in the field. These plantlets successfully acclimatized under field conditions. A Sequence Characterized Amplified Region (SCAR) marker was also developed using a 1135 bp amplicon that was obtained from RAPD (Random Amplification of Polymorphic DNA) analysis of six accessions of V. serpens. Testing of several market samples of V. serpens using the SCAR marker revealed successful identification of the genuine samples of V. serpens. This study, therefore, provides a proficient in vitro propagation protocol of V. serpens using leaf explants and a SCAR marker for the authentic identification of V. serpens. This study will be helpful for conservation of authentic V. serpens.

18.
Carbohydr Polym ; 231: 115740, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31888855

RESUMEN

Colorimetric nanocomposite film sensor was fabricated by incorporating TCFH spectroscopic probe into cellulose nanowhiskers (CNW)/Urease enzyme matrix. CNW-TCFH can be used as disposable molecular biosensor in which CNW is the probe carrier comprising high surface area-to-volume ratio, urease is the catalyst and TCFH is the molecular probe. Tricyanofuran-hydrazone (TCFH) spectroscopic probe was prepared. UV-vis absorption spectra demonstrated solvatochromic behavior and a reversible color change of the tricyanofuran-hydrazone probe solution in acetone under acid/base conditions. CNW were reinforced with sodium alginate biopolymer to introduce biocomposite film. This CNW-TCFH film biosensor responds through visible color shift from light yellow to pink when exposed to urea in aqueous media. The morphology properties of CNW and CNW-TCFH films were examined by different tools. The photophysical properties of the prepared TCFH probe, including solvatochromism and pH sensory, were also studied.

19.
Artículo en Inglés | MEDLINE | ID: mdl-31239852

RESUMEN

Diabetes mellitus (DM) is a metabolic disease that can affect the central nervous system and behavioral traits in animals. Streptozotocin-induced diabetes is considered an autoimmune disease. The aim of the current study was to determine whether supplementation with the alcoholic extract of Avicennia marina leaves could improve diabetes-associated pathological changes. The animals were divided into four groups: a control group (A), an A. marina receiving nondiabetic group (B), a diabetic group (C), and a DM group orally supplemented with A. marina alcoholic leaf extract (D). The DM group of animals receiving the alcoholic extract of A. marina leaves had reduced blood glucose levels, improved blood picture, and organ functions. This group also showed improvement in locomotory behavior. The results of this study showed that supplementation with the alcoholic extract of A. marina leaves reduced oxidative stress and blood sugar levels, protected the liver, and improved the neurobehavioral changes associated with diabetes in mice. Introducing alcoholic leaf extract of A. marina to diabetic mice decreased inflammatory cells aggregation, vacuolation, and hemorrhage. Additionally, a positive effect of the alcoholic leaf extract on the histopathological changes was observed in the testicular tissue of treated mice.

20.
Genes (Basel) ; 10(2)2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30791662

RESUMEN

Drought and heat factors have negative impacts on wheat yield and growth worldwide. Improving wheat tolerance to heat and drought stress is of the utmost importance to maintain crop yield. WRKY transcription factors help improve plant resistance to environmental factors. In this investigation, Arabidopsis WRKY30 (AtWRKY30) transcription factor was cloned and expressed in wheat. Plants growth, biomass, gas-exchange attributes, chlorophyll content, relative water content, prolines content, soluble proteins content, soluble sugars content, and antioxidant enzymes activities (catalase (CAT), superoxide dismutase (SOD), peroxidase (POX), and ascorbate peroxidase (APX)) of the AtWRKY30-overexpressing wheat plants were higher than those of the wild type. However, levels of electrolyte leakage, malondialdehyde, and hydrogen peroxide of the AtWRKY30-overexpressing wheat plants were significantly less than those of the wild-type. Additionally, the expression level of antioxidant enzyme-encoding genes and stress-responsive genes (ERF5a, DREB1, DREB3, WRKY19, TIP2, and AQP7) were significantly induced in the transgenic wheat plants in comparison with the wild type. In conclusion, the results demonstrated that AtWRKY30 overexpression promotes heat and drought tolerance in wheat by inducing gas-exchange attributes, antioxidant machinery, osmolytes biosynthesis, and stress-related gene expression. AtWRKY30 could serve as a potential candidate gene for improving stress tolerance in wheat.


Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/genética , Respuesta al Choque Térmico , Factores de Transcripción/genética , Transgenes , Triticum/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Presión Osmótica , Estrés Oxidativo , Factores de Transcripción/metabolismo , Triticum/metabolismo , Regulación hacia Arriba
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