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1.
Exp Parasitol ; 256: 108651, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944660

RESUMO

Infectious diseases such as malaria, dengue, and yellow fever are predominantly transmitted by insect vectors like Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus in tropical regions like India and Africa. In this study, we assessed the larvicidal activity of commonly found seaweeds, including Padina gymnospora, P. pavonica, Gracilaria crassa, Amphiroa fragilissima, and Spatoglossum marginatum, against these mosquito vectors. Our findings indicate that extracts from P. gymnospora Ethyl Acetate (PgEA), P. pavonica Hexane (PpH), and A. fragilissima Ethyl Acetate (AfEA) displayed the highest larval mortality rates for A. stephensi, with LC50 values of 10.51, 12.43, and 6.43 µg/mL, respectively. Additionally, the PgEA extract from P. gymnospora exhibited the highest mortality rate for A. aegypti, with an LC50 of 27.0 µg/mL, while the PgH extract from the same seaweed showed the highest mortality rate for C. quinquefasciatus, with an LC50 of 9.26 µg/mL. Phytochemical analysis of the seaweed extracts revealed the presence of 71 compounds in the solvent extracts. Fourier-transform infrared spectra of the selected seaweeds indicated the presence of functional groups such as alkanes, alcohols, and phenols. Gas chromatography-mass spectrometry analysis of the seaweeds identified major compounds, including hexadecanoic acid in PgEA, tetradecene (e)- in PpEA, octadecanoic acid in GcEA, and 7-hexadecene, (z)-, and trans-7-pentadecene in SmEA.


Assuntos
Aedes , Anopheles , Culex , Inseticidas , Alga Marinha , Animais , Inseticidas/análise , Larva , Alga Marinha/química , Phaeophyceae , Rodófitas/química
2.
Environ Res ; 228: 115917, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37062474

RESUMO

The present study investigated the growth, exopolymeric substance (EPS) production, and biosorption efficiency of strain Bacillus cereus KMS3-1 in the Cd2+ and Pb2+ ions containing single and binary metal-treated broth (50 mg/L). In addition, the interaction of the KMS3-1 strain with Cd2+ and Pb2+ ions in single and binary metal-treated broths was investigated using SEM-EDS, FTIR, and XRD analyses. The results showed that the biosorption efficiency (%) and EPS production of KMS3-1 biomass in both single and binary metal-treated broths had increased with increasing incubation time and were higher for Pb2+ ions than for Cd2+ ions. In the single and binary metal-treated broths, the maximum biosorption efficiency of KMS3-1 for Pb2+ ions were 70.8% and 46.3%, respectively, while for Cd2+ ions, they were 29.3% and 16.8%, respectively, after 72 h. Moreover, the biosorption efficiency of strain KMS3-1 for both metal ions was dependent on its EPS production and peaked at the maximum EPS production. The copious EPS production by KMS3-1 was observed in metal-treated media (50 mg/L), in the following order: Pb2+ ions (1925.7 µg/mL) > binary metal mixtures (1286.8 µg/mL) > Cd2+ ions (1185.5 µg/mL), > control (1099 µg/mL) after 72 h of incubation. This result indicates that the metal biosorption efficiency of the KMS3-1 strain was enhanced by the increased EPS production in the surrounding metal-treated broth. SEM-EDS and FTIR characterization studies revealed that the KMS3-1 biomass effectively adsorbed Cd2+ and Pb2+ ions from the medium by interacting with their surface functional groups (hydroxyl, carbonyl, carboxyl, amide, and phosphate). Moreover, the biosorbed Cd2+ and Pb2+ ions were transformed into CdS and PbS, respectively, by the KMS3-1 biomass. This study suggests that the Bacillus cereus KMS3-1 strain may be a promising candidate for the treatment of metal contamination.


Assuntos
Bacillus cereus , Cádmio , Adsorção , Cinética , Biomassa , Íons , Concentração de Íons de Hidrogênio
3.
Environ Monit Assess ; 195(10): 1186, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37695547

RESUMO

Nanoplastics (plastic particles smaller than 1 µm) are the least-known type of marine litter. Nanoplastics (NPs) have attracted much interest in recent years because of their prevalence in the environment and the potential harm they can cause to living organisms. This article focuses on understanding NPs and their fate in the marine environment. Sources of NPs have been identified, including accidental release from products or through nano-fragmentation of larger plastic debris. As NPs have a high surface area, they may retain harmful compounds. The presence of harmful additives in NPs poses unique practical challenges for studies on their toxicity. In this review, several methods specifically adapted for the physical and chemical characterization of NPs have been discussed. Furthermore, the review provides an overview of the translocation and absorption of NPs into organisms, along with an evaluation of the release of potential toxins from NPs. Further, we have provided an overview about the existing methods suggested for the possible degradation of these NPs. We conclude that the hazards of NPs are plausible but unknown, necessitating a thorough examination of NPs' sources, fate, and effects to better mitigate and spread awareness about this emerging contaminant.


Assuntos
Monitoramento Ambiental , Microplásticos , Plásticos/toxicidade
4.
Environ Res ; 212(Pt A): 113135, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35364041

RESUMO

Baseline assessments of marine microbial studies are very limited around ecologically sensitive areas of the Nuclear Power Plant (NPP) site with respect to their occurrence, distribution, role in adaptation, and their potential remediation process. The distribution and diversity of marine microbes are largely dependent on the physicochemical parameters relating to a specific area, especially spore-producing marine actinobacteria are a source for indigenous bioremediation agents. Marine actinobacterial diversity with conventional and 16 S rRNA gene analysis was done with different pre-treatment conditions and selective media. Totally, 170 different strains are identified in genera level and it belongs to 18 genera with dominant by Streptomyces sp. (75species) followed by Nocardiposis sp, (18species) Rhodococcus sp. (14species). Multiple k-dominance plots simplified the perception of marine actinobacteria according to genera level influence to standard stock. This is the first kind of study in India and the results could act as baseline inventory in terms of microbial diversity around NPP sites. Further, a potential strain of Actinomadura sp. (T5S13) produced 243.7 mg/L of EPS and remediate the Uranium radionuclides. The functional group shifting and adsorption nature were also confirmed by SEM with EDS analysis.


Assuntos
Actinobacteria , Urânio , Actinobacteria/genética , Bactérias/genética , DNA Bacteriano , Centrais Nucleares , Filogenia , RNA Ribossômico 16S/genética
5.
Curr Microbiol ; 78(1): 292-302, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33170381

RESUMO

Antibiotic resistance is one of the major concerns and the biggest threats to the world population. The incidents of antibiotic resistance in Candida spp. were frequently recorded. In the present investigation, antifungal potential of ascorbic acid (AA) was evaluated. According to the in vitro analysis, the zone of inhibition of AA (24.75 ± 0.35 mm) against C. albicans was greater as compared to other vitamins tested. AA significantly modulate the growth of C. albicans at 25 mg/ml. The highest percentage (94.67%) of cell viability was observed in untreated cells, and low cell viability (29.36%) was observed in cells treated with 50 mg/ml of AA (2 × MIC). Further, AO/EB (acridine orange/ethidium bromide), propidium iodide staining, and real-time qPCR confirmed the loss of membrane integrity due to membrane lesions that caused cell death. Lanosterol 14-α-demethylase (L-14α-DM) is the product of ERG11 and acted as superior drug target of C. albicans. Molecular docking analysis confirmed that active interaction of ascorbic acid with L-14α-DM. Based on the present investigation, the efficiency of AA was effectively proved through the in vitro and in silico analysis. This finding has evidenced the effectiveness of AA as a potential candidate against C. albicans.


Assuntos
Candida albicans , Fluconazol , Antifúngicos/farmacologia , Ácido Ascórbico/farmacologia , Farmacorresistência Fúngica , Fluconazol/farmacologia , Lanosterol/farmacologia , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Esterol 14-Desmetilase/genética , Esterol 14-Desmetilase/farmacologia
6.
Ecotoxicol Environ Saf ; 208: 111567, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396096

RESUMO

In this study, the production and compositional analysis of exopolysaccharides produced by Bacillus cereus KMS3-1 grown in metal amended conditions were investigated. In addition, the metal adsorption efficacy of exopolysaccharides (EPS) produced by KMS3-1 strain was evaluated in a batch mode. Increased production of exopolysaccharides by KMS3-1 strain was observed while growing under metal amended conditions (100 mg/L) and also, the yield was in the order of Pb(II)>Cu(II)>Cd(II)>Control. Characterization of EPS using FT-IR, XRD, and SEM analysis revealed that the EPS can interact with metal ions through their functional groups (O‒H, CH, CË­O, C‒O, and C‒CË­O) and assist the detoxification process. Further, equilibrium results were fitted with the Langmuir model and notably, the maximum adsorption capacity (Qmax) of EPS for Cd(II), Cu(II), and Pb(II) found to be 54.05, 71.42, and 78.74 mg/g, respectively. To the best of our knowledge, EPS demonstrating proficient metal adsorption was substantiated by XRD analysis in this study. Owing to good adsorbing nature, the exopolysaccharides could be used as chelating substances for wastewater treatment.


Assuntos
Metais Pesados/toxicidade , Polissacarídeos Bacterianos , Adsorção , Bactérias , Quelantes , Polissacarídeos , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Bioorg Chem ; 104: 104256, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32942217

RESUMO

Marine natural products are recognised as one among the major contributors of several important biological functions. The arguments has made to utilization of natural products against different kinds of infectious diseases. In the present study, Callophycin A was successfully prepared and its anti-candidal activity was evaluated through in-vitro and in-vivo methods. The in-vitro results revealed that, Callophycin A significantly inhibits the azole resistant and sensitive C. albicans. Further, in-vivo animal experiments have shown the effective reduction in CFU of C. albicans from its beginning day of the treatment as compared to the disease control group. At the end of Callophycin A administration, there was a decrease in inflammatory response and immune molecules such as IL-6, IL-12, IL-17, IL-22, TNF-α, macrophages, CD4 and CD8 cells were observed. Whereas the animals in the disease control group expressed all the parameters with the elevated level as compared to the control group. There are no hematological abnormalities such as neutropenia, lymphocytosis and eosinophilia was observed in any animal groups except the disease control group. Finally, the evidence based prediction of anti-candidal efficacious of Callophycin A was demonstrated.


Assuntos
Antifúngicos/farmacologia , Candidíase Vulvovaginal/tratamento farmacológico , Carbolinas/farmacologia , Alga Marinha/química , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Candidíase Vulvovaginal/patologia , Carbolinas/química , Carbolinas/isolamento & purificação , Relação Dose-Resposta a Droga , Farmacorresistência Fúngica/efeitos dos fármacos , Feminino , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
8.
Mikrochim Acta ; 187(6): 334, 2020 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-32417978

RESUMO

A method for the amperometric determination of Myo-inositol is presented. Nanostructured copper sulfide material was synthesized by solvothermal method and utilized as sensor matrix. The physico-chemical analysis using XRD, Raman, FE-SEM, TEM, and XPS confirmed the formation of CuS material. The voltammetric response of CuS-modified glassy carbon electrode for a successive Myo-inositol (0.5 µM) addition confirmed that the reaction takes place at the surface of the electrode. The modified electrode resulted in signal enhancement for a linear response ranging from 0.5-8.5 µM at an applied overpotential of 0.65 V with a correlation coefficient value (R2) of 0.99. The sensitivity and limit of detection of the modified electrode were 7.87 µA µM-1 cm-2 and 0.24 µM, respectively. The interfering effect of various compounds present in real samples was examined. Graphical abstract Schematic representation of synthetic protocol of nanostructured CuS and Myo-inositol oxidation on CuS-modified glassy carbon electrode in basic medium.


Assuntos
Cobre/química , Inositol/urina , Nanoestruturas/química , Biomarcadores/química , Biomarcadores/urina , Carbono/química , Técnicas Eletroquímicas , Eletrodos , Humanos , Inositol/química , Limite de Detecção , Oxirredução
9.
Microb Pathog ; 132: 343-354, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31100406

RESUMO

In the present study, an attempt has been made to explore the antibiofilm activity of bioactive compound 1-hydroxy-1-norresistomycin (HNM) derived from coral mucus associated actinomycete Streptomyces variabilis. Initially, different concentration of HNM inhibited the biofilm formation of human clinical pathogens Escherichia coli, Vibrio cholerae and Staphylococcus aureus was determined using crystal-violet staining assay. The light microscopic analysis showed that HNM reduced the biofilm formation and adherence of bacterial cells on the surface of coverslip. HNM also damages the 3D architecture with reduced thickness as well as cell aggregation of biofilm forming bacteria analysed by confocal laser scanning microscopy (CLSM). In addition, HNM also demonstrated the efficiency in inhibiting theoretical adhesion by altering the surface hydrophobicity that can potentially hamper cellular adhesion and prevent biofilm formation. Furthermore, the molecular docking showed the significant interaction between HNM and key biofilm forming proteins proved an excellent antibiofilm activity of HNM. Together, these results suggest that the HNM can serve as potential antibiofilm agent in controlling the infections of E. coli, V. cholerae and S. aureus.


Assuntos
Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Pirenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Vibrio cholerae/efeitos dos fármacos , Actinobacteria/metabolismo , Animais , Antozoários/microbiologia , Fator de Transcrição AraC/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Proteínas de Bactérias/efeitos dos fármacos , Simulação por Computador , Cisteína Endopeptidases/efeitos dos fármacos , Proteínas de Escherichia coli/efeitos dos fármacos , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Pirenos/química , Streptomyces/metabolismo , Transativadores/efeitos dos fármacos , Peixe-Zebra
10.
Bioorg Chem ; 83: 326-335, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30396117

RESUMO

Graphene oxide (GO) has been recently attracted considerable interest for its potential applications in physical, chemical and biological properties. In the present study, the GO nanosheets were prepared by a chemical exfoliation technique using a modified Hummers method. Initially, the prepared GO nanosheets were confirmed by UV-vis spectroscopy and further characterized by FE-SEM, Edax, HR-TEM and SAED that demonstrated the formation of GO nanosheets with few layers flat sheet structure with hexagonal lattice crystalline nature. The FTIR spectra revealed the presence of various oxygen containing functional groups has been produced from graphite plane by exfoliation technique. The prepared GO nanosheets showed excellent antibiotic resistant activity against planktonic bacteria and more effective to damage the established biofilms and inhibits the biofilm formation of human clinical pathogens like E. coli and P. aeruginosa. Further, the GO nanosheets were found to be non-toxic to normal mammalian cells and there are no apparent morphological changes were observed in control and treated cells. In conclusion, GO nanosheets were effectively preventing the formation of biofilms and kills the represent bacteria that suggested the GO nanosheets could be used for the prevention and treatment of biofilm-related infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Grafite/farmacologia , Nanoestruturas/química , Antibacterianos/síntese química , Antibacterianos/toxicidade , Escherichia coli/efeitos dos fármacos , Grafite/síntese química , Grafite/toxicidade , Nanoestruturas/toxicidade , Pseudomonas aeruginosa/efeitos dos fármacos
11.
Bioorg Chem ; 90: 103072, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31260877

RESUMO

In the present study pufferfish, Arothron immaculatus muscle methanol extract (AIME) was used to evaluate the antidiabetic activity against the high-fat diet (HFD) in streptozotocin (STZ) induced diabetic rat models. Initially, the In vitro antioxidant activity of the different muscle extract was evaluated which showed that AIME has higher efficiency to scavenge the free radicals. The animal study results revealed that the AIME could decrease the blood glucose level after 14 days of oral treatment and recover the animal from the severe progression of the disease. The LC-ESI/MS analysis of AIME extract revealed the presence of compounds such as docosahexaenoic acid, adrenic acid, docosanol, codeine and metoprolol. Among these compounds, docosahexaenoic acid, adrenic acid and docosanol are reported for its antidiabetic studies. Hence, the muscle is recommended to consume by humans as natural food in order to overcome the development of diabetes. This is the first study on the muscle extract of marine pufferfish which is used as antidiabetic agent to treat the diabetes-induced in the animal model.


Assuntos
Antioxidantes/farmacologia , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Dieta Hiperlipídica/efeitos adversos , Hipoglicemiantes/farmacologia , Músculo Esquelético/química , Tetraodontiformes/fisiologia , Animais , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/patologia , Insulina/sangue , Masculino , Ratos , Ratos Wistar
12.
Environ Monit Assess ; 189(6): 288, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28536912

RESUMO

The heavy metal concentrations in water and sediment samples were investigated in the tropical Muthupet mangrove ecosystem, southeast coast of India. The results demonstrated that, ranges of metals in water comprise of Cd-0.05 to 3.72; Cu-0.5 to 4.43; Pb-6.31 to 17.87; Zn-0.0 to12.91 ppm and sediment comprises of Cd-0.06 to 0.57; Cu-4.46 to 20.59; Pb-2.90 to 21.35; Zn-4.41 to 39.18 ppm. In all the three sites, heavy metals in sediment exhibited significant higher concentrations compared to water, except Cd. The spatial distribution of metals in water and sediment samples followed a similar pattern except Cd with the preponderance of Zn (75% of total metals) followed by Cu and Pb. Muller's Geoaccumulation indexes (Igeo) showed Cd is a potent pollutant in the ecosystem and moderately contaminated the study area. The aquaculture and agricultural culture practices follow improper disposal of municipal wastages, and idol immersion activities are the potent metallic sources for heavy metal pollution were identified by performing principle component analysis. In order to protect the ecosystem from further contamination, regular monitoring is needed to in order to control the anthropogenic discharges. Graphical abstract.


Assuntos
Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Metais Pesados/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Agricultura , Aquicultura , Ecossistema , Poluição Ambiental/análise , Sedimentos Geológicos/análise , Índia
13.
Analyst ; 139(13): 3356-9, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24846089

RESUMO

We report a novel seedless Hg(2+)-induced synthetic approach for the preparation of gold nanostructures. This protocol is demonstrated for the highly selective and sensitive naked eye detection of Hg(2+) based on the high affinity metallophilic Hg(2+)-Au(+) interaction. The response time upon exposure to Hg(2+) is almost instantaneous.


Assuntos
Ouro/química , Mercúrio/análise , Nanopartículas Metálicas/química , Cátions Bivalentes/análise , Cetrimônio , Compostos de Cetrimônio/química , Colorimetria
14.
Sci Total Environ ; 924: 171580, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462004

RESUMO

The study focused on marine bacteria, specifically Bacillus cereus, sourced from heavily polluted coastal areas in Tamil Nadu, aiming to assess their efficacy in degrading low-density polyethylene (LDPE) and polystyrene over a 42-day period. When LDPE and polystyrene films were incubated with Bacillus cereus, they exhibited maximum weight losses of 4.13 ± 0.81 % and 14.13 ± 2.41 %, respectively. Notably, polystyrene exhibited a higher reduction rate (0.0036 day-1) and a shorter half-life (195.29 days). SEM images of the treated LDPE and polystyrene unveiled surface erosion with cracks. The energy dispersive X-ray (EDX) analysis revealed elevated carbon content and the presence of oxygen in the treated LDPE and polystyrene films. The ATR-FTIR spectra exhibited distinctive peaks corresponding to functional groups, with observable peak shifts in the treated films. Notable increases were detected in carbonyl, internal double bond, and vinyl indices across all treated groups. Additionally, both treated LDPE and polystyrene showed reduced crystallinity. This research sheds light on Bacillus cereus (OR268710) biodegradation capabilities, emphasizing its potential for eco-friendly waste management in coastal regions.


Assuntos
Polietileno , Poliestirenos , Polietileno/metabolismo , Bacillus cereus/metabolismo , Índia , Biodegradação Ambiental , Plásticos/metabolismo
15.
Chem Biol Interact ; 369: 110282, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36427553

RESUMO

The present study aims to investigate the effect and the molecular mechanism of N-(2-hydroxyphenyl)-2-phenazinamine (NHP) isolated from Nocardiopsis exhalans against the proliferation of human lung cancer cells. The cytotoxic activity of NHP against A549 and H520 cells was determined using MTT assay. The cytotoxic activity of NHP against A549 and H520 lung cancer cells showed excellent activity at 75 µg/mL and damage the mitochondrial membrane and nucleus by generating oxidative stress. NHP causes nuclear condensation and induces apoptosis which was confirmed using AO/EB and PI/DAPI dual staining assay. Moreover, the NHP downregulates the oncogenic genes such as IL-8, TNFα, MMPs and BcL2 and also upregulates the expression of apoptosis marker genes such as Cyto C, p53, p21, caspase 9/3 in A549 and H520 human lung cancer cells. Considering the strong anticancer activity of NHP against lung cancer, NHP may be further evaluated as a potential anticancer drug for the treatment of lung cancer.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Apoptose , Antineoplásicos/uso terapêutico , Células A549 , Proliferação de Células
16.
Chemosphere ; 310: 136737, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36228726

RESUMO

The concentrations of five heavy metals (Cd, Cr, Cu, Pb, and Zn) in the sediments, water, phytoplankton, zooplankton, and macroalgae from Kongsfjorden Fjord and the freshwater lakes of Ny-Ålesund in the Svalbard archipelago were determined in order to describe the anthropogenic impacts related to the Ny-Ålesund town. Water samples from nine stations, sediment samples from 23 stations, plankton samples from five stations, and six species of macroalgae were collected and subjected to heavy metal analysis using atomic absorption spectrophotometry (AAS). Only Cu and Zn were detected in the water samples. The plankton samples had only Zn, Cu, and Cr. The average metal concentrations in macroalgae fell in the decreasing order of Cu > Zn > Cr > Cd > Pb. In sediment samples, the metal order was as follows: Zn > Cu > Cr > Pb > Cd. Multivariate statistical analyses including principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to identify the source of the metal contamination. The metals were found to originate from a blend of both anthropogenic and geogenic sources. Pollution monitoring indices including geoaccumulation index (Igeo), contamination factor, contamination degree (Cdeg), pollution load index (PLI), and potential ecological risk (PER) were calculated using the metal data. In the study area, Igeo values of the metals showed pollution grades from 0 (uncontaminated) to 6 (extremely contaminated). Cdeg fell in classes from 1 (low contamination) to 4 (very high contamination). PLI values ranged between 0 and 5.68. PER values expressed that except for a few stations located at higher elevations in the glacial outwash plains, all other sites were highly polluted. The high level of pollution indices in the sites can be attributed to the anthropogenic activities persistent in the study area.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Lagos , Monitoramento Ambiental , Estuários , Svalbard , Cádmio/análise , Chumbo/análise , Metais Pesados/análise , Medição de Risco , Água/análise , Sedimentos Geológicos , Poluentes Químicos da Água/análise , China
17.
Dalton Trans ; 52(18): 6041-6051, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37043252

RESUMO

In this work, multiwalled carbon nanotubes (MWCNTs) are functionalized using 4-nitrobenzenediazonium (NBD) salt, which is identified as an effective electrocatalyst for the detection of ß-nicotinamide adenine dinucleotide (NADH). The NBD functionalized MWCNT (NBD-MWCNT(w) (w-washed)) was characterized using various physicochemical characterization methods. Cyclic voltammetric measurements showed that NBD-MWCNT(w) modified glassy carbon electrode (NBD-MWCNT(w)/GCE) was able to produce the anodic wave for oxidizing NADH at the applied overpotential of 0.12 V, which is 0.67 V cathodic when compared to that of bare GCE. Besides, the sensitivity of the electrode also doubled. The sensitivity and limit of detection (LoD) were 8.5 × 10-4 A M-1 and 3.75 µM, respectively. The linear range of the sensor was 5 to 60 µM. The selectivity studies further proved that the matrix is specific towards detecting NADH in the presence of other possible interfering molecules. The diffusion co-efficient and apparent rate constant of NADH obtained were 3.8 × 10-6 cm2 s-1 and 1.12 × 107 mol-1 cm3 s-1 respectively. Additionally, the electrode is employed to detect the analyte in real samples.

18.
J Fungi (Basel) ; 9(8)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37623571

RESUMO

Candida spp. are common opportunistic microorganisms in the human body and can cause mucosal, cutaneous, and systemic infections, mainly in individuals with weakened immune systems. Candida albicans is the most isolated and pathogenic species; however, multi-drug-resistant yeasts like Candida auris have recently been found in many different regions of the world. The increasing development of resistance to common antifungals by Candida species limits the therapeutic options. In light of this, the present review attempts to discuss the significance of marine natural products in controlling the proliferation and metabolism of C. albicans and non-albicans species. Natural compounds produced by sponges, algae, sea cucumber, bacteria, fungi, and other marine organisms have been the subject of numerous studies since the 1980s, with the discovery of several products with different chemical frameworks that can inhibit Candida spp., including antifungal drug-resistant strains. Sponges fall under the topmost category when compared to all other organisms investigated. Terpenoids, sterols, and alkaloids from this group exhibit a wide array of inhibitory activity against different Candida species. Especially, hippolide J, a pair of enantiomeric sesterterpenoids isolated from the marine sponge Hippospongia lachne, exhibited strong activity against Candida albicans, Candida parapsilosis, and Candida glabrata. In addition, a comprehensive analysis was performed to unveil the mechanisms of action and synergistic activity of marine products with conventional antifungals. In general, the results of this review show that the majority of chemicals derived from the marine environment are able to control particular functions of microorganisms belonging to the Candida genus, which can provide insights into designing new anti-candidal therapies.

19.
Chemosphere ; 319: 138020, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36731676

RESUMO

Human hair and nail samples from Cuddalore fisherfolk populations were used as biomarkers for assessing metal concentrations in humans. Hair samples from 80 participants (47 men and 33 women) and nail samples from 40 participants (21 men and 19 women) were collected, and the concentrations of Cd, Cu, Pb, and Zn were assessed using an atomic absorption spectrophotometer (AAS). Metal data from AAS were compared with the survey questionnaire's personal and dietary parameters. Results indicate that both personal and dietary parameters may influence metal exposure; however, majority of the sources may have originated from metal-contaminated seafood. Higher metal accumulation in communities, especially those which consume seafood on a daily basis, may increase the possibility for them to get affected by metal-related diseases. Based on environmental parameters, people who live ≤500 m from industrial zones accumulate more metals. Further extensive studies with more individuals and more questionnaire parameters are needed to identify the metal accumulation pathway in humans.


Assuntos
Metais Pesados , Masculino , Humanos , Feminino , Metais Pesados/análise , Monitoramento Ambiental/métodos , Cabelo/química , Biomarcadores , Dieta
20.
J Mol Model ; 29(11): 344, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37847395

RESUMO

CONTEXT: This research focused on the theoretical investigation of transition metal carbonyls [M(CO)4] coordinated with terminal germanium chalcogenides complexes [M(CO)3GeX], where M represents Ni, Pd, and Pt and X represents O, S, Se, and Te labeled 1-15. While the notable complexes M(CO)4 (where M = Ni, Pd, Pt) numbered 1, 6, and 11 are of significance, substituting one of the CO ligands in 1, 6, and 11 with a GeX ligand (where X = O, S, Se, or Te) result in substituted complexes (2-5, 7-10, and 11-15). Substituting of the CO ligand slightly alters these bond angles. Specifically, the ∠CMC bond angles for [Ni] complexes range from 111.9° to 112.2°, for [Pd] complexes from 111.4° to 111.7°, and for [Pt] complexes from 112.4° to 112.8°. These findings indicate a minor deviation from the tetrahedral geometry due to the influence of the new GeX ligand. Similarly, there is a slight change in the geometry of the metal complexes, where the ∠GeMC angles for [Ni] complexes are between 106.7° and 106.9°, for [Pd] complexes between 107.2° and 107.5°, and for [Pt] complexes between 105.9° and 106.4°. Comparing among the substituted GeX complexes, those containing GeTe exhibit a higher natural bond orbital (NBO) contribution from the Ge atom compared to the M atom. Consequently, based on the above observations, it can be inferred that GeX acts as an effective sigma donor in contrast to carbonyl compounds. Results of energy decomposition analysis (EDA) for the M-CO bond in 1, 6, and 11 and for the M-GeX bond in the other [M(CO)3(GeX)] complexes where M = Ni, Pd and Pt. The percentage contribution of ΔEelstat and ΔEorb shows a relatively identical behavior for all ligands in case of each metal complexes. METHODS: Density functional theory (DFT) calculations were conducted using the B3LYP/gen/6-31G*/LanL2DZ level of theory to examine transition metal carbonyls [M(CO)4] coordinated with terminal germanium chalcogenides complexes [M(CO)3GeX], where M represents Ni, Pd, and Pt, and X represents O, S, Se, and Te labeled 1-15 utilized through the use of Gaussian 09W and GaussView 6.0.16 software packages. Post-processing computational code such as multi-wave function was employed for results analysis and visualization.

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