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1.
Mol Pharm ; 20(2): 1382-1393, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36583939

RESUMO

The study aimed to improve the treatment of impetigo with naturally occurring quercetin and its copper-quercetin (Cu-Q) complex by preparing sustained-release (SR) nanoparticles of polycaprolactone (PCL). The solvent evaporation method was used for the copper-quercetin (Cu-Q) complex formation, and their PCL nanoparticles (PCL-NPs, Q-PCL-NPs, and Cu-Q-PCL-NPs) were prepared by the high-pressure homogenization method. Synthesis of nanoparticles was confirmed by their physicochemical and antibacterial properties of quercetin against Gram-positive as well as Gram-negative bacteria. The percentage loading efficiency of quercetin and release in 100 mM of phosphate buffer pH 7.4 and 5.5 at 37 °C was found to be more than 90% after 24 h with the zero-order release pattern. Minimum inhibitory concentration of nanoparticles was found to increase threefold in the case of Cu-Q-PCL-NPs may be due to the synergistic antibacterial behavior. Scanning electron microscopy showed spherical nanoparticles, and surface roughness was confirmed by atomic force microscopy analysis. Fortunately, no sign of irritation on rat skin even at 3%, was seen. In vitro antioxidant assay by 2,2-diphenyl-1-picrylhydrazyl reduction was found to be ≤80 ± 0.02% which confirmed their scavenging activity. Interestingly, for the ex vivo study, the tape-stripping model was applied against Staphylococcus aureus containing rats and showed the formation of the epidermal layer within 4-5 days. Confirmation of antibacterial activity of pure quercetin, from Cu-Q complex, and their SR release from Q-PCL-NPs and Cu-Q-PCL-NPs was considered an effective tool for the treatment of skin diseases and can be used as an alternative of already resistant ciprofloxacin in impetigo.


Assuntos
Impetigo , Nanopartículas , Ratos , Animais , Quercetina/farmacologia , Quercetina/uso terapêutico , Quercetina/química , Cobre/química , Preparações de Ação Retardada , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/química
2.
Int J Phytoremediation ; 25(12): 1656-1668, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36855239

RESUMO

Microbes have shown potential for the bioremediation of tannery waste polluted soil. During our previous study, it was observed that heavy metal resistant Burkholderia cepacia CS8 augmented growth and phytoremediation capability of an ornamental plant. Objective of the present research work was to evaluate the capability of B. cepacia CS8 assisted Calendula officinalis plants for the phytoremediation of tannery solid waste (TSW) polluted soil. The TSW treatment significantly reduced growth attributes and photosynthetic pigments in C. officinalis. However, supplementation of B. cepacia CS8 which exhibited substantial tolerance to the TSW amended soil, augmented growth traits, carotenoid, proline, and antioxidant enzymes level in C. officinalis under toxic and nontoxic regimes. Inoculation of B. cepacia CS8 augmented plant growth (shoot length 13%, root length 11%), physiological attributes (chlorophyll a 14%, chlorophyll b 17%), antioxidant enzyme activities (peroxidase 24%, superoxide dismutase 31% and catalase 19%), improved proline 36%, phenol 32%, flavonoids 14% and declined malondialdehyde (MDA) content 15% and hydrogen peroxide (H2O2) level 12% in C. officinalis at TSW10 stress compared with relevant un-inoculated plants of TSW10 treatment. Moreover, B. cepacia CS8 application enhanced labile metals in soil and subsequent metal uptake, such as Cr 19%, Cd 22%, Ni 35%, Fe 18%, Cu 21%, Pb 34%, and Zn 30%, respectively in C. officinalis plants subjected to TSW10 stress than that of analogous un-inoculated treatment. Higher plant stress tolerance and improved phytoremediation potential through microbial inoculation will assist in the retrieval of agricultural land in addition to the renewal of native vegetation.


During the current study, it was observed that combination of Calendula officinalis and metal tolerant Burkholderia cepacia CS8 not only improved plant growth but also helped phyto-extraction of pollutants present in the tannery solid waste polluted soil. According to our information, research work describing the phytoremediation potential of native metal tolerant microbes and ornamental plants has not been reported in Pakistan.


Assuntos
Burkholderia cepacia , Calendula , Metais Pesados , Poluentes do Solo , Antioxidantes , Clorofila A , Biodegradação Ambiental , Resíduos Sólidos , Peróxido de Hidrogênio , Solo , Poluentes do Solo/análise
3.
Int J Phytoremediation ; 24(4): 364-372, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34282979

RESUMO

During the current study, the effects of magnesium oxide nanoparticles (5 mmol/L) were observed on the growth and mineral nutrients of Daucus carota under lead (Pb) stress. The results demonstrated that Pb stress decreased the growth and photosynthetic rate of D. carota plants. Furthermore, Pb stressed plants showed decreased uptake of mineral nutrients including Zn, Na, Fe, K, Ca, Mg, K, and Cu. Similarly, Pb stressed plants showed enhanced electrolyte leakage (EL) and malondialdehyde (MDA) content. However, magnesium oxide nanoparticles detoxified ROS to mitigate Pb stress and improved the growth of plants. Magnesium oxide nanoparticles also escalated the activity of antioxidant enzymes including superoxide dismutase (SOD) and Catalase (CAT). A higher amount of Pb content was observed in the roots as compared to the shoot of plants. Lead toxicity reduced manganese accumulation in D. carota plants. The increased concentration of iron, manganese, copper, and zinc advocates stress the ameliorative role of Pb stress in plants. Novelty statementThe role of MgONPs in the alleviation of Pb-toxicity in Daucus carota has never been exploited. In addition, the potential of MgONPs to enhance nutritional content in D. carota via modulation in antioxidant system and polyamines have never been reported.


Assuntos
Daucus carota , Nanopartículas , Antioxidantes , Biodegradação Ambiental , Chumbo/toxicidade , Óxido de Magnésio , Poliaminas , Superóxido Dismutase
4.
Ecotoxicol Environ Saf ; 213: 112047, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33601172

RESUMO

In this study, we have evaluated the role of karrikin (KAR1) against the absorption and translocation of a persistent organic pollutant (POP), 2,4,4'-Tribromodiphenyl ether (BDE-28) in plants, in the presence of two other stressors, cadmium (Cd) and high temperature. Furthermore, it correlates the physiological damages of Brassica alboglabra with the three stresssors separately. The results revealed that the post-germination application of KAR1 successfully augmented the growth (200%) and pertinent physiochemical parameters of B. alboglabra. KAR1 hindered air absorption of BDE-28 in plant tissues, and reduced its translocation coefficient (TF). Moreover, BDE-28 was the most negatively correlated (-0.9) stressor with chlorophyll contents, while the maximum mitigation by KAR1 was also achieved agaist BDE-28. The effect of temperature was more severe on soluble sugars (0.51), antioxidative machinery (-0.43), and osmoregulators (0.24). Cd exhibited a stronger inverse interrelation with the enzymatic antioxidant cascade. Application of KAR1 mitigated the deleterious effects of Cd and temperature stress on plant physiological parameters along with reduced aero-concentration factor, TF, and metal tolerance index. The phytohormone reduced lipid peroxidation by decreasing synthesis of ROS and persuading its breakdown. The stability of cellular membranes was perhaps due to the commotion of KAR1 as a growth-promoting phytohormone. In the same way, KAR1 supplementation augmented the membrane stability index, antioxidant defense factors, and removal efficiency of the pollutants. Consequently, the exogenously applied KAR1 can efficiently alleviate Cd stress, heat stress, and POP toxicity.


Assuntos
Brassica/fisiologia , Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Antioxidantes/metabolismo , Brassica/metabolismo , Cádmio/metabolismo , Clorofila/metabolismo , Furanos , Germinação/efeitos dos fármacos , Peroxidação de Lipídeos , Reguladores de Crescimento de Plantas/metabolismo , Bifenil Polibromatos , Piranos
5.
Small ; 16(25): e2001551, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32459055

RESUMO

The luminous efficiency of inorganic white light-emitting diodes, to be used by the next generation as light initiators, is continuously progressing and is an emerging interest for researchers. However, low color-rendering index (Ra), high correlated color temperature (CCT), and poor stability limit its wider application. Herein, it is reported that Sm3+ - and Eu3+ -doped calcium scandate (CaSc2 O4 (CSO)) are an emerging deep-red-emitting material with promising light absorption, enhanced emission properties, and excellent thermal stability that make it a promising candidate with potential applications in emission display, solid-state white lighting, and the device performance of perovskite solar cells (PSCs). The average crystal structures of Sm3+ -doped CSO are studied by synchrotron X-ray data that correspond to an extremely rigid host structure. Samarium ion is incorporated as a sensitizer that enhances the emission intensity up to 30%, with a high color purity of 88.9% with a 6% increment. The impacts of hosting the sensitizer are studied by quantifying the lifetime curves. The CaSc2 O4 :0.15Eu3+ ,0.03Sm3+ phosphor offers significant resistance to thermal quenching. The incorporation of lanthanide ion-doped phosphors CSOE into PSCs is investigated along with their potential applications. The CSOE-coated PSCs devices exhibit a high current density and a high power conversion efficiency (15.96%) when compared to the uncoated control devices.

6.
J Sci Food Agric ; 100(4): 1616-1624, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31773731

RESUMO

BACKGROUND: Brassica oleracea var. alboglabra (Chinese kale) is an important vegetable grown in southern China. This study was aimed at searching for environmentally friendly and affordable approaches to increase the production of medicinally relevant glucosinolates and phenolic compounds in Chinese kale plants. For this purpose, the foliar application of liquiritin at 0 (control), 250, 500 and 750 ppm was tested starting from the four-leaf stage and repeated every two weeks until plants were two months old. RESULTS: Foliar application of liquiritin in Chinese kale plants significantly increased glucosinolates and total phenolic content, in a dose-dependent manner. Compared with control plants, 2.3- and 1.9-fold increases in yields of glucosinolates and total phenolic content, respectively, were corroborated in Chinese kale plants treated with 750 ppm of liquiritin. Along with rises in the content of eight different glucosinolates, liquiritin elicitation effectively increased the concentration of glycosilated and acylated flavonoids and hydroxycinnamic acids. The expression of genes involved in glucosinolate and phenolic biosynthesis was significantly higher in liquiritin-treated plants as compared to controls. CONCLUSIONS: Liquiritin elicitation is a feasible and environmentally friendly practice for increasing the production of medicinally important glucosinolates and phenolic compounds in Chinese kale, which may improve this plant's value as a nutraceutical food. This study also contributes to understanding the molecular mechanisms underlying liquiritin elicitation. This is the first report documenting the use of liquiritin for an elicitation purpose in plants. © 2019 Society of Chemical Industry.


Assuntos
Brassica/metabolismo , Produção Agrícola/métodos , Flavanonas/farmacologia , Glucosídeos/farmacologia , Glucosinolatos/análise , Fenóis/análise , Brassica/química , Brassica/efeitos dos fármacos , China , Produção Agrícola/instrumentação , Flavonoides/análise , Flavonoides/metabolismo , Glucosinolatos/metabolismo , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Verduras/química , Verduras/efeitos dos fármacos , Verduras/metabolismo
7.
Bioconjug Chem ; 30(1): 13-28, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30508381

RESUMO

For SLN lymph node biopsy (SLNB), SLN mapping has become a standard of care procedure that can accurately locate the micrometastases disseminated from primary tumor sites to the regional lymph nodes. The broad array of SLN mapping has prompted the development of a wide range of SLN tracers, rationally designed for noninvasive and high-resolution imaging of SLNs. At present, conventional SLN imaging probes (blue dyes, radiocolloids, and few other small-molecular dyes), although serving the clinical needs, are often associated with major issues such as insufficient accumulation in SLN, short retention time, staining of the surgical field, and other adverse side effects. In a recent advancement, newly designed fluorescent nanoprobes are equipped with novel features that could be of high interest in SLN mapping such as (i) a unique niche that is not met by any other conventional SLN probes, (ii) their adoptable synthesis method, and (ii) excellent sensitivity facilitating high resolution SLN mapping. Most importantly, lots of effort has been devoted for translating the fluorescent nanoprobes into a clinical setup and also imparting the multimodal imaging abilities of nanoprobes for the excellent diagnosis of life-threatening diseases such as cancer. In this review, we will provide a detailed roadmap of the progress of a wide variety of current fluorescent molecular probes and emphasize the future of nanomaterial-based single/multimodal imaging probes that have true potential translation abilities for SLN mapping.


Assuntos
Corantes Fluorescentes/química , Sondas Moleculares/química , Biópsia de Linfonodo Sentinela/métodos , Animais , Humanos , Verde de Indocianina/química , Metástase Linfática , Micrometástase de Neoplasia , Teoria Quântica , Linfonodo Sentinela/patologia , Solubilidade
8.
Pak J Pharm Sci ; 32(3 (Supplementary)): 1137-1143, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31303582

RESUMO

The aim of study was cross linking of high molecular weight chitosan nanoparticles containing 5-fluorouracil to improve dissolution rate and ultimately enhance its bioavailability by reverse emulsion/micelles method and cross-linking agent i.e. glutaraldehyde (GA 25% aqueous solution in water). The nature and outer morphologies were evaluated by scanning electron microscopy (SEM). Drug release models were functional to support way from cross linked NPs. Cross linking of 5-fluorouracil with glutaraldehyde improved dissolution rate. Mean dissolution time of 5-fluorouracil decreased significantly upon reverse emulsion/cross linking as encapsulated drug is protective and thermally stable within cross linked chitosan NPs. FTIR studies showed formation of intermolecular hydrogen bonding between 5-fluorouracil and GA-co-CHNPs. DSC studies indicated a less crystalline state of 5-fluorouracil in cross linking. SEM showed spherical nanoparticles with somewhat rough surface. 5-FU release followed Korsmeyer-Peppas model which indicate diffusion and dissociation control drug release from GA-co-CH-NPs. 5-FU cross linked chitosan nanoparticles can be safe and useful tool for other chemotherapeutic agents.


Assuntos
Quitosana/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Fluoruracila/farmacocinética , Nanopartículas/química , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Reagentes de Ligações Cruzadas/química , Estabilidade de Medicamentos , Fluoruracila/química , Glutaral/química , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Peso Molecular , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Clin Infect Dis ; 67(5): 785-790, 2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-30124823

RESUMO

Background: A clinical trial showed that efavirenz 400 mg once daily (EFV400) is as effective as the standard adult dose. World Health Organization recommends EFV400 as an alternative first-line agent, but data are lacking in the third trimester of pregnancy (TT). We investigated the pharmacokinetics, efficacy, and CYP2B6 pharmacogenetics in HIV-infected women (WLWH) on EFV400 during TT and post-partum (PP). Methods: An open-label 2-center study (United Kingdom, Uganda) was conducted in WLWH receiving antiretroviral regimens containing efavirenz 600 mg, who had their efavirenz dose reduced to EFV400. Weekly therapeutic drug monitoring (TDM), steady-state pharmacokinetic profiles (TT and PP), safety, virological efficacy, and CYP2B6 polymorphisms at positions 516 (C > T) and 938 (T > C) were evaluated. Results: Twenty-five WLWH of African origin were enrolled. All had viral loads <50 copies/mL at baseline, which were maintained throughout the study. No infant was HIV infected. No WLWH were withdrawn due to low EFV400 TDM results. Geometric mean ratios (TT/PP; 90% confidence interval) for EFV400 maximum observed plasma concentration, area under the curve, and plasma concentration measured 24 hours after the observed dose were 0.97 (.85-1.10), 0.87 (.76-.99), and 0.77 (.65-.91), respectively. Five of 25 WLWH were slow metabolizers. Conclusions: Although EFV400 pharmacokinetic parameters were slightly lower for TT compared with PP values, efavirenz concentrations exceeded cutoff levels established by the study and those measured in antiretroviral-naive patients receiving EFV400 in ENCORE1. All subjects maintained a viral load <50 copies/mL, suggesting that EFV400 can be used in pregnant WLWH.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/farmacocinética , Benzoxazinas/administração & dosagem , Benzoxazinas/farmacocinética , Infecções por HIV/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adulto , Alcinos , Ciclopropanos , Monitoramento de Medicamentos , Feminino , HIV-1/efeitos dos fármacos , Humanos , Farmacogenética , Período Pós-Parto , Gravidez , Complicações Infecciosas na Gravidez/virologia , Uganda , Reino Unido , Carga Viral
10.
Inorg Chem ; 57(24): 15229-15239, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30495940

RESUMO

In this study, nitrogen-doped green emissive carbon dots (N-doped CDs) are synthesized via a convenient one-step solid state reaction method. The N-doped CDs show excitation-dependent fluorescence behavior with a maximum emission of 540 nm. Upon the optimum excitation at 400 nm, the quantum yield (QY) of the green emissive CDs is determined to be 13.4% and 50.3% in deionized water and ethanol, respectively. The higher quantum yield of N-doped CDs in ethanol could be caused by a strong hydrogen-bonding. In addition, the obtained N-doped CDs demonstrate excellent thermal stability, which is supported by the fact that the emission intensity nearly has no change after keeping the sample at 90 °C for 120 min. Moreover, the N-doped CDs exhibit green emission after entering into the HeLa cell membrane, indicating their potential to be used as bioimaging agent. Furthermore, the N-doped CDs are dispersed in PVA matrix for solid state film, where the solid-state quenching  is effectively avoided. A green LED is fabricated by packing the CDs-PVA composite on the top of a 395 nm n-UV-Chip, which provides a potentially healthy green light.


Assuntos
Carbono/química , Corantes Fluorescentes/química , Nitrogênio/química , Imagem Óptica , Pontos Quânticos/química , Temperatura , Membrana Celular/química , Células HeLa , Humanos , Conformação Molecular , Tamanho da Partícula
11.
Int J Phytoremediation ; 20(6): 581-592, 2018 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-29688047

RESUMO

The current study was performed to assess the effect of Burkholderia cepacia CS8 on the phytoremediation of cadmium (Cd) by Catharanthus roseus grown in Cd-contaminated soil. The plants cultivated in Cd amended soil showed reduced growth, dry mass, gas-exchange capacity, and chlorophyll contents. Furthermore, the plants exhibited elevated levels of malondialdehyde (MDA) and hydrogen peroxide (H2O2) under Cd stress. The bacterized plants showed higher shoot length, root length; fresh and dry weight. The improved stress tolerance in inoculated plants was attributed to the reduced quantity of MDA and H2O2, enhanced synthesis of protein, proline, phenols, flavonoids, and improved activity of antioxidant enzymes including peroxidase, superoxide dismutase, ascorbate peroxidase, and catalase. Similarly, the 1-aminocyclopropane-1-carboxylate deaminase activity, phosphate solubilization, auxin, and siderophore production capability of B. cepacia CS8 improved growth and stress alleviation in treated plants. The bacterial inoculation enhanced the amount of water extractable Cd from soil. Furthermore, the inoculated plants showed higher bioconcentration factor and translocation factor. The current study exhibits that B. cepacia CS8 improves stress alleviation and phytoextraction potential of C. roseus plants growing under Cd stress.


Assuntos
Burkholderia cepacia , Catharanthus , Biodegradação Ambiental , Cádmio , Peróxido de Hidrogênio
12.
Int J Phytoremediation ; 20(3): 274-283, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29053340

RESUMO

Heavy metal contaminated agricultural soils are one of the most important constraints for successful cultivation of crops. The current research was conducted to evaluate the role of potassium (K) on plant growth and amelioration of cadmium (Cd) stress in Gladiolus grandiflora under greenhouse conditions. G. grandiflora corms were sown in media contaminated with 0 (C), 50 (Cd50) and 100 (Cd100) mg Cd kg-1 soil. The plants growing in Cd-contaminated media exhibited reduced gas exchange attributes, chlorophyll (Chl) contents, vegetative and reproductive growth as compared to control. The plants raised in Cd contaminated media showed reduced nutrition yet higher Cd contents. However, supplementation of 60 mg Kg-1 K in treated plants (C+K, Cd50+K and Cd100+K) improved quantity of total soluble protein and proline (Pro) along with activity of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) under Cd stress. Similarly, K supplementation reduced the level of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in treated plants. Potassium supplemented plants exhibited better vegetative and reproductive growth. The improved stress tolerance in K supplemented plants was attributed to the reduced quantity of MDA and H2O2, enhanced synthesis of protein, proline, phenols, flavonides and improved activity of antioxidant enzymes. The present research supports the application of K for alleviation of Cd stress in G. grandiflora.


Assuntos
Cádmio , Potássio , Biodegradação Ambiental , Peróxido de Hidrogênio , Raízes de Plantas
13.
Int J Phytoremediation ; 19(6): 514-521, 2017 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-27819493

RESUMO

The remediation of heavy metal-contaminated soils has become a critical issue due to toxic effects of these metals on living organisms. The current research was conducted to study the effect of Pseudomonas fluorescens RB4 and Bacillus subtilis 189 on the growth and phytoremediation potential of Catharanthus roseus in Cu- and Pb-contaminated soils. The bacterial strains exhibited significantly higher level of water-extractable Pb and Cu in Pb, Cu, and Cu+Pb-contaminated. The P. fluorescens RB4 inoculated plants, produced 102%, 48%, and 45% higher fresh weight (FW) in soils contaminated with Cu, Pb, and both elements, respectively, as compared to un-inoculated control plants. Similarly, B. subtilis 189 inoculated plants produced 108%, 43%, and 114% more FW in the presence of Cu, Pb, and both elements. The plants co-cultivated with both bacteria exhibited 121%, 102%, and 177% higher FW, in Cu, Pb, and both elements contaminated soils, as compared to respective un-inoculated control. Co-cultivation of P. fluorescens RB4, B. subtilis 189, and P. fluorescens RB4 + B. subtilis 189 resulted in higher accumulation of Cu and Pb in shoots of the C. roseus grown in contaminated soils as compared to un-inoculated control. Bacterial treatments also improved the translocation and metal bioconcentration factors. The growth and phytoextraction capability of C. roseus was improved by inoculation of P. fluorescens RB4 and B. subtilis 189.


Assuntos
Bacillus subtilis/fisiologia , Catharanthus/metabolismo , Cobre/metabolismo , Chumbo/metabolismo , Pseudomonas fluorescens/fisiologia , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Catharanthus/crescimento & desenvolvimento , Catharanthus/microbiologia
14.
Int J Phytoremediation ; 19(5): 470-477, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27739873

RESUMO

In our current study, four nickel-tolerant (Ni-tolerant) bacterial species viz, Bacillus thuringiensis 002, Bacillus fortis 162, Bacillus subtilis 174, and Bacillus farraginis 354, were screened using Ni-contaminated media. The screened microbes exhibited positive results for synthesis of indole acetic acid (IAA), siderophore production, and phosphate solubilization. The effects of these screened microbes on Ni mobility in the soil, root elongation, plant biomass, and Ni uptake in Althea rosea plants grown in Ni-contaminated soil (200 mg Ni kg-1) were evaluated. Significantly higher value for water-extractable Ni (38 mg kg-1) was observed in case of Ni-amended soils inoculated with B. subtilis 174. Similarly, B. thuringiensis 002, B. fortis 162, and B. subtilis 174 significantly enhanced growth and Ni uptake in A. rosea. The Ni uptake in the shoots and roots of B. subtilis 174-inoculated plants enhanced up to 1.7 and 1.6-fold, respectively, as compared to that in the un-inoculated control. Bacterial inoculation also significantly improved the root and shoot biomass of treated plants. The current study presents a novel approach for bacteria-assisted phytoremediation of Ni-contaminated areas.


Assuntos
Althaea/metabolismo , Bacillus/metabolismo , Níquel/metabolismo , Poluentes do Solo/metabolismo , Althaea/crescimento & desenvolvimento , Althaea/microbiologia , Biodegradação Ambiental
15.
Int J Phytoremediation ; 19(9): 813-824, 2017 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-28699781

RESUMO

The current research was performed to evaluate the effect of Bacillus megaterium MCR-8 on mitigation of nickel (Ni) stress in Vinca rosea grown on Ni-contaminated soil (50, 100, and 200 mg Ni kg-1 soil). The treated plants exhibited reduced growth, biomass, gas exchange capacity, and chlorophyll (Chl) content under Ni stress. The inoculated plants growing in Ni-contaminated media exhibited relatively higher growth, total soluble protein, and proline contents. Similarly, bacterial inoculation improved the activity of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX) under Ni stress. The Ni stress alleviation in inoculated plants was attributed to the reduced level of malondialdehyde (MDA) and hydrogen peroxide (H2O2), enhanced synthesis of protein, proline, phenols, and flavonides in conjunction with improved activity of antioxidant enzymes. The growth-promoting characteristics of microbe such as 1-aminocyclopropane-1-carboxylate deaminase (ACCD) and phosphate solubilization activity, siderophore, and auxin production capability also improved the growth and stress mitigation in inoculated plants. Furthermore, the inoculated plants exhibited higher value for bioconcentration factor (BCF), translocation factor (TF), and resulted in higher loss of Ni content from soil. The current results exhibited the beneficial role of B. megaterium MCR-8 regarding stress alleviation and Ni phytoextraction by V. rosea.


Assuntos
Bacillus megaterium , Biodegradação Ambiental , Catharanthus , Níquel , Peróxido de Hidrogênio , Poluentes do Solo
16.
J Sep Sci ; 39(4): 793-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26632078

RESUMO

In the present work, novel molecularly imprinted polymer porous beads for the selective separation of copper ions have been synthesized by combining two material-structuring techniques, namely, molecular imprinting and oil-in-water-in-oil emulsion polymerization. This method produces monodisperse spherical beads with an average diameter of ∼2-3 mm, in contrast to adsorbents produced in the traditional way of grinding and sieving. Field-emission scanning electron microscopy indicates that the beads are porous in nature with interconnected pores of about 25-50 µm. Brunner-Emmett-Teller analysis shows that the ion-imprinted beads possess a high surface area (8.05 m(2) /g), and the total pore volume is determined to be 0.00823 cm(3) /g. As a result of the highly porous nature and ion-imprinting, the beads exhibit a superior adsorption capacity (84 mg/g) towards copper than the non-imprinted material (22 mg/g). Furthermore, selectivity studies indicate that imprinted beads show splendid recognizing ability, that is, nearly fourfold greater selective binding for Cu(2+) in comparison to the other bivalent ions such as Mn(2+) , Ni(2+) , Co(2+) , and Ca(2+) . The imprinted composite beads prepared in this study possess uniform porous morphology and may open up new possibilities for the selective removal of copper ions from waste water/contaminated matrices.

17.
Analyst ; 140(21): 7366-72, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26381602

RESUMO

Salmonella enterica serotype Typhi (S. Typhi) is the causative agent of typhoid fever and remains a major health threat in most of the developing countries. The prompt diagnosis of typhoid directly from the patient's blood requires high level of sensitivity and specificity. Some of us were the first to report PCR based diagnosis of typhoid. This approach has since then been reported by many scientists using different genomic targets. Since the number of bacteria circulating in the blood of a patient can be as low as 0.3 cfu ml(-1), there is always a room for improvement in diagnostic PCR. In the present study, the role of different types of nanoparticles was investigated to improve the existing PCR based methods for diagnosis and strain typing of S. Typhi (targeting Variable Number of Tandem Repeats [VNTR]) by using optimized PCR systems. Three different types of nanoparticles were used i.e., citrate stabilized gold nanoparticles, rhamnolipid stabilized gold and silver nanoparticles, and magnetic iron oxide nanoparticles. The non-specific amplification was significantly reduced in VNTR typing when gold and silver nanoparticles were used in an appropriate concentration. More importantly, the addition of nanoparticles decreased the non-specificity to a significant level in the case of multiplex PCR thus further validating the reliability of PCR for the diagnosis of typhoid.


Assuntos
Técnicas de Tipagem Bacteriana , Nanopartículas Metálicas/química , Reação em Cadeia da Polimerase/métodos , Salmonella typhi/classificação , Febre Tifoide/diagnóstico , Febre Tifoide/microbiologia , Proteínas de Bactérias/química , Primers do DNA/química , Proteínas de Escherichia coli/genética , Compostos Férricos/química , Flagelina , Ouro/química , Magnetismo , Repetições Minissatélites , Nanotecnologia/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Prata/química , Temperatura
18.
Int J Biol Macromol ; 277(Pt 4): 134167, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39067724

RESUMO

Diarrhea is a globally major problem especially Escherichia coli induced diarrhea becoming fatal nowadays in developing countries. Colon-targeted chitosan microspheres (Ms) comprising of lipase­zinc and lipase­copper complexes were prepared, loaded with Attapulgite (Cts-Li-Zn-ATG/Ms and Cts-Li-Cu-ATG/Ms) for the treatment of bacterial diarrhea. Thin layer chromatography (TLC) and Fourier-transform infrared spectroscopy (FTIR) studies were used for confirmation of proposed lipase-metal complexes. Ms showed particle size range 18 ± 0.24 to 23 ± 0.83 µm, zeta potential -13.7 ± 0.71 to -29.3 ± 1.34 mV, PDI 0.5 ± 0.04 to 1.0 ± 0.07 and hemolytic activity was found to be <5 ± 1.25 %. After coating with Eudragit S-100 for colon targeting, in-vitro % drug release of ATG at pH 7.4 was 80 ± 0.21 % for Eud-Cts-Li-Zn-ATG/Ms while it was increased to 83 ± 0.54 % for Eud-Cts-Li-Cu-ATG/Ms within 7 h, respectively. In-vivo anti-diarrheal activity of Eud-Cts-Li-Zn-ATG/Ms and Eud-Cts-Li-Cu-ATG/Ms was performed by oral challenge on albino mice having infectious diarrhea colonized with E. coli. Results revealed significant anti-diarrheal effect of proposed Eud-Cts-Li-Cu-ATG/Ms in terms of weight gain from 24 ± 0.12 g to 26.05 ± 0.31 g, which was 2-fold increase as compared to Eud-Cts-Li-Zn-ATG/Ms. Conclusively, Eud-Cts-Li-Cu-ATG/Ms provides an innovative alternate for the treatment of bacterial diarrhea with additional support of chitosan and lipase for nutritional support and immunity which was compromised in diarrheal patients.


Assuntos
Quitosana , Cobre , Diarreia , Escherichia coli , Lipase , Compostos de Magnésio , Microesferas , Compostos de Silício , Cobre/química , Quitosana/química , Animais , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Escherichia coli/efeitos dos fármacos , Camundongos , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Lipase/metabolismo , Compostos de Silício/química , Compostos de Silício/farmacologia , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia
19.
J Mater Chem B ; 11(47): 11290-11299, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38013459

RESUMO

The abuse of antibiotics has led to serious environmental pollution and the emergence of drug-resistant bacteria surpassing the replacement rate of antibiotics. Herein, near-infrared fluorescent carbon dots (NIR-CDs) were developed to meet the requirements for oxytetracycline (OTC) detection in food and water samples (milk, honey, and lake water) with a detection limit of 0.112 µM. These NIR-CDs, possessing excellent water-solubility, deep tissue penetration ability, and tunable optical properties, exhibit maximum emission at 790 nm (NIR-I window). Unlike traditional CDs, this novel NIR-CDs nanoprobe provides a dual response in the presence of OTC (quenching and bathochromic shifting), without obvious interference from other existing biomolecules and metal ions. Additionally, these NIR-CDs exhibit excellent photostability and multi-resistance under UV irradiation, exceptional pH stability (pH 6-12), reliable long-time exposure, and durability in ionic (NaCl) environments. Moreover, NIR-CDs and NIR-CDs@OTC are nontoxic and were successfully utilized for cell-imaging applications in normal (NIH3T3) and cancer cells (HeLa).


Assuntos
Oxitetraciclina , Pontos Quânticos , Animais , Camundongos , Pontos Quânticos/química , Carbono/química , Fluorescência , Células NIH 3T3 , Antibacterianos/farmacologia , Corantes Fluorescentes/química , Água
20.
Talanta ; 265: 124781, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348356

RESUMO

Dopamine (DA) is a biomolecule that plays a critical part in the functioning of our brains by promoting motivation, maintaining focus, and altering mood. Excessive or low-level concentrations of DA in the human brain led to a dangerous neurological disorder. It is significantly important to trace the precise amount of DA to prevent such risky brain disease. Recently, heteroatoms-doped carbon dots (H-CDs) have attracted great attention for their capacity to detect biomolecules, metal ions, organic solvents, chemical dyes, etc. In this review, we have provided a comprehensive summary of the emerging trends in the heteroatom functional dopamine-doped carbon dots (DA-CDs), which are based on DA used as starting substances or functionalizing agents. Our analysis encompasses a detailed exploration of the synthetic methods, physical and chemical properties of carbon dots derived from dopamine, as well as their diverse range of applications. Additionally, we have also discussed the application of H-CDs in the dopmine detection by using various fluorescent, colorimetric, and electrochemical techniques.


Assuntos
Dopamina , Pontos Quânticos , Humanos , Dopamina/análise , Carbono/química , Corantes Fluorescentes/química , Pontos Quânticos/química
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