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1.
Ecotoxicol Environ Saf ; 277: 116383, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663192

RESUMO

Vanillic acid (4-hydroxy-3-methoxybenzoic acid) (VA) is a natural benzoic acid derivative commonly found in herbs, rice, maize, and some fruits and vegetables. However, due to the wide use of VA in various industrial sectors, its presence in the environment might harm living organisms. This study evaluated the toxicity of VA and its isomers, iso-VA and orto-VA. Firstly, the antimicrobial effect of VA and its isomers iso-VA and orto-VA (in doses of 1000; 100, 10, 1; 0.1; 0.01 mg/L) against Escherichia coli, Sarcina spp., Enterobacter homaechei, Staphylococcus aureus and Candida albicans were identified. The toxic effect and protein degradation potential of VA and its isomers were determined using E. coli grpE:luxCDABE and lac:luxCDABE biosensor strains. However, the genotoxicity and oxidative stress generation were assessed with the E. coli recA:luxCDABE biosensor and E. coli strain. The results showed that VA, iso-VA, and orto-VA exhibited antimicrobial activity against all tested bacterial strains. However, VA's antimicrobial effect differed from iso-VA and orto-VA. Similar toxic, genotoxic, and oxidative stress-inducing effects were observed for VA and its isomers. Each compound exhibited toxicity, cellular protein degradation, and genotoxic activity against E. coli grpE:luxCDABE, E. coli lac:luxCDABE, and E. coli recA:luxCDABE strains. Analysis of reactive oxygen species (ROS) generation within E. coli cells highlighted oxidative stress as a contributing factor to the toxicity and genotoxicity of VA and its isomers. While the findings suggest potential applications of VA compounds as food preservatives, their presence in the environment raises concerns regarding the risks posed to living organisms due to their toxic and genotoxic characteristics.


Assuntos
Escherichia coli , Estresse Oxidativo , Ácido Vanílico , Ácido Vanílico/farmacologia , Ácido Vanílico/toxicidade , Escherichia coli/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Testes de Mutagenicidade , Antibacterianos/toxicidade , Antibacterianos/farmacologia , Anti-Infecciosos/toxicidade , Anti-Infecciosos/farmacologia
2.
Cell Biochem Biophys ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39384699

RESUMO

Type 2 diabetes (T2D), also known as non-insulin-dependent diabetes mellitus, represents the prevailing manifestation of diabetes, encompassing a substantial majority of cases, ~90-95%. Plant-derived antidiabetic leads are being intensively explored due to their safety and effectiveness. The main objective of the present study is to evaluate the anti-diabetic potential of the traditional formulation Karisalai Karpam through in-vitro and in-silico investigations. The in-vitro and in-silico investigation of traditional polyherbal preparation Karisalai Karpam (KK) chooranam were performed to ascertain its inhibitory potential against α-amylase and α-glucosidase enzymes along with antioxidant (DPPH and ABTS) and phytochemical analysis. The results of enzyme inhibitory activity of KK witnessed highest activity against α-glucosidase enzyme with a percentage inhibition of 84.66 ± 2.50% (IC50,187.9 ± 5.79 µg/ml) followed by moderate level of α-amylase inhibition exhibited with 72.94 ± 3.66% (IC50, 241.6 ± 9.76 µg/ml). Additionally, the strongest antioxidant activity was observed in quenching DPPH• (IC50,154.8 ± 14.53 µg/ml) and ABTS+• radicals (IC50,148.6 ± 29.74 µg/ml). The outcome of the molecular docking studies indicated that among the 17 compounds analysed, the lead such as acalyphin, apigenin, humulene, and indirubin exhibited a prominent binding affinity over the residual binding site of α-glucosidase. It's important to note that the catalytic site of the enzyme α-amylase is primarily occupied by amyrin, apigenin, arjunolic acid, ß-sitosterol, geraniol, and tricetin. In conclusion, the formulation KK demonstrates robust alpha-glucosidase and alpha-amylase inhibitory activity. It's also worth noting that the formulation exhibits noteworthy antioxidant properties, which could provide additional health benefits. The binding mode and energies of the identified phytochemicals against the target enzymes further support the formulation's antidiabetic potential.

3.
Cell Biochem Biophys ; 82(3): 2473-2492, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39042185

RESUMO

Chronic hepatitis caused by the hepatitis C virus (HCV) is closely linked with the advancement of liver disease. The research hypothesis suggests that the NS5B enzyme (non-structural 5B protein) of HCV plays a pivotal role in facilitating viral replication within host cells. Hence, the objective of the present investigation is to identify the binding interactions between the structurally diverse phytotherapeutics and those of the catalytic residue of the target NS5B polymerase protein. Results of our docking simulations reveal that compounds such as arjunolic acid, sesamin, arjungenin, astragalin, piperic acid, piperidine, piperine, acalyphin, adhatodine, amyrin, anisotine, apigenin, cuminaldehyde, and curcumin exhibit a maximum of three interactions with the catalytic residues (Asp 220, Asp 318, and Asp 319) present on the Hepatitis C virus NS5B polymerase of HCV. Molecular dynamic simulation, particularly focusing on the best binding lead compound, arjunolic acid (-8.78 kcal/mol), was further extensively analyzed using RMSD, RMSF, Rg, and SASA techniques. The results of the MD simulation confirm that the NS5B-arjunolic acid complex becomes increasingly stable from 20 to 100 ns. The orientation of both arjunolic acid and sofosbuvir triphosphate (standard) within the active site was investigated through DCCM, PCA, and FEL analysis, indicating highly stable interactions of the lead arjunolic acid with the catalytic region of the NS5B enzyme. The findings of our current investigation suggest that bioactive therapeutics like arjunolic acid could serve as promising candidates for limiting the NS5B polymerase activity of the hepatitis C virus, offering hope for the future of HCV treatment.


Assuntos
Hepacivirus , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteínas não Estruturais Virais , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Hepacivirus/enzimologia , Hepacivirus/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Antivirais/metabolismo , Domínio Catalítico , Humanos , Ligação Proteica , Sítios de Ligação , Ligação de Hidrogênio , Fitoterapia , RNA Polimerase Dependente de RNA
4.
Sensors (Basel) ; 13(5): 6394-404, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23673679

RESUMO

Whole cell biosensors always face the challenge of low stability of biological components and short storage life. This paper reports the effects of poly(2-hydroxyethyl methacrylate) (pHEMA) immobilization on a whole cell fluorescence biosensor for the detection of heavy metals (Cu, Pb, Cd), and pesticides (dichlorophenoxyacetic acid (2,4-D), and chlorpyrifos). The biosensor was produced by entrapping the cyanobacterium Anabaena torulosa on a cellulose membrane, followed by applying a layer of pHEMA, and attaching it to a well. The well was then fixed to an optical probe which was connected to a fluorescence spectrophotometer and an electronic reader. The optimization of the biosensor using several factors such as amount of HEMA and drying temperature were undertaken. The detection limits of biosensor without pHEMA for Cu, Cd, Pb, 2,4-D and chlorpyrifos were 1.195, 0.027, 0.0100, 0.025 and 0.025 µg/L respectively. The presence of pHEMA increased the limits of detection to 1.410, 0.250, 0.500, 0.235 and 0.117 µg/L respectively. pHEMA is known to enhance the reproducibility of the biosensor with average relative standard deviation (RSD) of ±1.76% for all the pollutants tested, 48% better than the biosensor without pHEMA (RSD = ±3.73%). In storability test with Cu 5 µg/L, the biosensor with pHEMA performed 11.5% better than the test without pHEMA on day-10 and 5.2% better on day-25. pHEMA is therefore a good candidate to be used in whole cell biosensors as it increases reproducibility and enhances biosensor storability.


Assuntos
Técnicas Biossensoriais/métodos , Cianobactérias/metabolismo , Metais Pesados/análise , Praguicidas/análise , Ácido 2,4-Diclorofenoxiacético/análise , Ácido 2,4-Diclorofenoxiacético/toxicidade , Células Imobilizadas/citologia , Células Imobilizadas/efeitos dos fármacos , Clorpirifos/análise , Clorpirifos/toxicidade , Cianobactérias/citologia , Cianobactérias/efeitos dos fármacos , Cianobactérias/crescimento & desenvolvimento , Fluorescência , Hidrogéis/farmacologia , Metais Pesados/toxicidade , Praguicidas/toxicidade , Poli-Hidroxietil Metacrilato/farmacologia , Temperatura , Fatores de Tempo
5.
Polymers (Basel) ; 14(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956578

RESUMO

The manufacturing of materials, in conjunction with green technology, emphasises the need to employ renewable resources to ensure long-term sustainability. Re-exploring renewable elements that can be employed as reinforcing materials in polymer composites has been a major endeavour. The research goal is to determine how well palm kernel cake filler (PKCF) performs in reinforced epoxy composites. In this study, PKCF with 100 mesh was mixed with epoxy resin (ER) in various ratios ranging from 10% to 40% by weight. Hand lay-up with an open mould is proposed as a method for fabricating the specimen test. Surface modification of PKCF with varying concentrations of NaOH (5 wt.% and 10 wt.%) will be contrasted with the untreated samples. Using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC), the effect of alkaline treatment will be examined. The tensile and maximum flexural strength of the untreated PKCF/ER composite were determined in this work, with a 30 wt.% of PKCF having the highest tensile strength of 31.20 MPa and the highest flexural strength of 39.70 MPa. The tensile and flexural strength were reduced to 22.90 MPa and 30.50 MPa, respectively, when the filler loading was raised to 40 wt.%. A 5 wt.% alkali treatment for 1 h improved the composites' mechanical characteristics. Lastly, an alkali treatment can aid in the resolution of the problem of inadequate matrix and filler interaction. Alkaline treatment is a popular and effective method for reducing the hydroxyl group in fillers and, thus, improving interfacial bonding. Overall, palm kernel cake is a promising material used as a filler in polymer composites.

6.
Materials (Basel) ; 15(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36013848

RESUMO

Green mussel and crab shells are natural sources of CaCO3, which is widely used as a bioceramic for biomedical applications, although they are commonly disposed of in landfills. The improper disposal of green mussel and crab shells can cause environmental pollution, reducing the quality of life in the community. Many studies have reported the preparation of CaCO3 from green mussels and crab shells. However, there are limited studies comparing the characteristics, including the crystal phase obtained, weight percentage (%) of crystal, crystal size, crystal system, and elemental composition of CaCO3 from green mussel shells, crab shells, and commercial CaCO3. The objective of this research was to compare the calcium carbonate properties formed from green mussel (PMS) and crab (PCS) shells to commercial CaCO3. Green mussel and crab shells were crushed to powder and were calcined at 900 °C for 5 h. Precipitated Calcium Carbonate (PCC) was synthesized from calcined green mussel and crab shells using a solution of 2M HNO3, NH4OH, and CO2 gas. The effect of setting parameters on the synthesized product was analyzed using XRD and SEM-EDX methods. This study shows that the chemical composition of PMS is nearly identical to that of commercial CaCO3, where no contaminants were identified. In contrast, PCS has N components other than Ca, C, and O. Furthermore, the predominance of the vaterite crystal phases in PMS and PCS, with respective weight percentages of 91.2% and 98.9%, provides a benefit for biomaterial applications. The crystallite sizes of vaterite in PMS, PCS, and calcite in commercial CaCO3 are 34 nm, 21 nm, and 15 nm, respectively.

7.
Polymers (Basel) ; 13(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34833158

RESUMO

Awareness of environmental concerns influences researchers to develop an alternative method of developing natural fiber composite materials, to reduce the consumption of synthetic fibers. This research attempted testing the neem (Azadirachta indica) fiber and the banyan (Ficus benghalensis) fiber at different weight fractions, under flame retardant and thermal testing, in the interest of manufacturing efficient products and parts in real-time applications. The hybrid composite consists of 25% fiber reinforcement, 70% matrix material, and 5% bran filler. Their thermal properties-short-term heat deflection, temperature, thermal conductivity, and thermal expansion-were used to quantify the effect of potential epoxy composites. Although natural composite materials are widely utilized, their uses are limited since many of them are combustible. As a result, there has been a lot of focus on making them flame resistant. The thermal analysis revealed the sample B was given 26% more short-term heat resistance when the presence of banyan fiber loading is maximum. The maximum heat deflection temperature occurred in sample A (104.5 °C) and sample B (99.2 °C), which shows a 36% greater thermal expansion compared with chopped neem fiber loading. In sample F, an increased chopped neem fiber weight fraction gave a 40% higher thermal conductivity, when compared to increasing the bidirectional banyan mat of this hybrid composite. The maximum flame retardant capacity occurred in samples A and B, with endurance up to 12.9 and 11.8 min during the flame test of the hybrid composites.

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