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1.
BMC Plant Biol ; 24(1): 92, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321391

RESUMO

BACKGROUND: The biochemical and growth changes resulting from exposure of basil (Ocimum basilicum L.) seedlings to silver nanoparticles and silver were investigated. Over a two-week period, seedlings were exposed to different concentrations (0, 40, and 80 ppm) of silver nanoparticles and silver. RESULTS: Our findings revealed that at concentrations of 40 and 80 ppm, both silver nanoparticles and silver nitrate led to decreased weight, root and shoot length, as well as chlorophyll a and b content. Conversely, these treatments triggered an increase in key biochemical properties, such as total phenols, carotenoids and anthocyanins, with silver nanoparticles showing a more pronounced effect compared to silver nitrate. Moreover, the levels of malondialdehyde (MDA) and hydrogen peroxide (H2O2) rose proportionally with treatment concentration, with the nanoparticle treatment exhibiting a more substantial increase. Silver content showed a significant upswing in both roots and leaves as treatment concentrations increased. CONCLUSIONS: Application of varying concentrations of silver nanoparticles and silver nitrate on basil plants resulted in reduced growth and lower chlorophyll content, while simultaneously boosting the production of antioxidant compounds. Notably, anthocyanin, carotenoid, and total phenol increased significantly. However, despite this increase in antioxidant activity, the plant remained unable to fully mitigate the oxidative stress induced by silver and silver nanoparticles.


Assuntos
Nanopartículas Metálicas , Ocimum basilicum , Clorofila A , Nitrato de Prata/farmacologia , Antocianinas , Peróxido de Hidrogênio/farmacologia , Prata , Antioxidantes/farmacologia , Carotenoides , Folhas de Planta
2.
World J Microbiol Biotechnol ; 40(7): 231, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833075

RESUMO

To investigate the mechanism of Triton X-100 (TX-100) reducing the Ag+-resistance of Enterococcus faecalis (E. faecalis), and evaluate the antibacterial effect of TX-100 + Ag+ against the induced Ag+-resistant E. faecalis (AREf). The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of AgNO3 against E. faecalis with/without TX-100 were determined to verify the enhanced antibacterial activity. Transmission electron microscopy (TEM) was used to observe the morphological changes of E. faecalis after treatment. The intra- and extracellular concentration of Ag+ in treated E. faecalis was evaluated using inductively coupled plasma mass spectrometer (ICP-MS). The changes in cell membrane potential and integrity of treated E. faecalis were also observed using the flow cytometer. Moreover, AREf was induced through continuous exposure to sub-MIC of Ag+ and the antibacterial effect of TX-100 + Ag+ on AREf was further evaluated. The addition of 0.04% TX-100 showed maximal enhanced antibacterial effect of Ag+ against E. faecalis. The TEM and ICP-MS results demonstrated that TX-100 could facilitate Ag+ to enter E. faecalis through changing the membrane structure and integrity. Flow cytometry further showed the effect of TX-100 on membrane potential and permeability of E. faecalis. In addition, the enhanced antibacterial effect of TX-100 + Ag+ was also confirmed on induced AREf. TX-100 can facilitate Ag+ to enter E. faecalis through disrupting the membrane structure and changing the membrane potential and permeability, thus reducing the Ag+-resistance of E. faecalis and enhancing the antibacterial effect against either normal E. faecalis or induced AREf.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Enterococcus faecalis , Testes de Sensibilidade Microbiana , Octoxinol , Prata , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Octoxinol/farmacologia , Antibacterianos/farmacologia , Prata/farmacologia , Membrana Celular/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Nitrato de Prata/farmacologia
3.
Clin Oral Investig ; 27(11): 6677-6688, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37775587

RESUMO

OBJECTIVES: Disinfection of alginate impression materials is a mandatory step to prevent cross-infection in dental clinics. However, alginate disinfection methods are time-consuming and exert a negative impact on accuracy and mechanical properties. Thus, this study aimed to prepare disinfecting agents (CHX and AgNO3) and silver nanoparticles reduced by a natural plant extract to produce a self-disinfecting dental alginate. METHODS: Conventional alginate impression material was used in this study. Silver nitrate (0.2% AgNO3 group) and chlorohexidine (0.2% CHX group) solutions were prepared using distilled water, and these solutions were later employed for alginate preparation. Moreover, a 90% aqueous plant extract was prepared from Boswellia sacra (BS) oleoresin and used to reduce silver nitrate to form silver nanoparticles that were incorporated in the dental alginate preparation (BS+AgNPs group). The plant extract was characterized by gas chromatography/mass spectrometry (GC/MS) analysis while green-synthesized silver nanoparticles (AgNPs) were characterized by UV-visible (UV-vis) spectroscopy and scanning electron microscopy (SEM). An agar disc diffusion assay was used to test the antimicrobial activity against Candida albicans, Streptococcus mutans, Escherichia coli, methicillin-resistant and susceptible Staphylococcus aureus strains, and Micrococcus luteus. Agar plates were incubated at 37 ± 1 °C for 24 h to allow microbial growth. Diameters of the circular inhibition zones formed around each specimen were measured digitally by using ImageJ software. RESULTS: Chemical analysis of the plant extract revealed the presence of 41 volatile and semi-volatile active compounds. UV-Vis spectrophotometry, SEM, and EDX confirmed the formation of spherical silver nanoparticles using the BS extract. CHX, AgNO3, and the BS+AgNPs modified groups showed significantly larger inhibition zones than the control group against all tested strains. BS+AgNPs and CHX groups showed comparable efficacy against all tested strains except for Staphylococcus aureus, where the CHX-modified alginate had a significantly higher effect. CONCLUSIONS AND CLINICAL RELEVANCE: CHX, silver nitrate, and biosynthesized silver nanoparticles could be promising inexpensive potential candidates for the preparation of a self-disinfecting alginate impression material without affecting its performance. Green synthesis of metal nanoparticles using Boswellia sacra extract could be a very safe, efficient, and nontoxic way with the additional advantage of a synergistic action between metal ions and the phytotherapeutic agents of the plant extract.


Assuntos
Alginatos , Nanopartículas Metálicas , Alginatos/farmacologia , Desinfecção , Nitrato de Prata/farmacologia , Nanopartículas Metálicas/química , Ágar/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Prata , Extratos Vegetais/farmacologia , Staphylococcus aureus , Nanotecnologia/métodos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
4.
Int J Mol Sci ; 24(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36982258

RESUMO

The antimicrobial activity of the novel coordination polymers obtained by co-crystallizing the amino acids arginine or histidine, as both enantiopure L and racemic DL forms, with the salts Cu(NO3)2 and AgNO3 has been investigated to explore the effect of chirality in the cases of enantiopure and racemic forms. The compounds [Cu·AA·(NO3)2]CPs and [Ag·AA·NO3]CPs (AA = L-Arg, DL-Arg, L-His, DL-His) were prepared by mechanochemical, slurry, and solution methods and characterized by X-ray single-crystal and powder diffraction in the cases of the copper coordination polymers, and by powder diffraction and by solid-state NMR spectroscopy in the cases of the silver compounds. The two pairs of coordination polymers, [Cu·L-Arg·(NO3)2·H2O]CP and [Cu·DL-Arg·(NO3)2·H2O]CP, and [Cu·L-Hys·(NO3)2·H2O]CP and [Cu·DL-His·(NO3)2·H2O]CP, have been shown to be isostructural in spite of the different chirality of the amino acid ligands. A similar structural analogy could be established for the silver complexes on the basis of SSNMR. The activity against the bacterial pathogens Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus was assessed by carrying out disk diffusion assays on lysogeny agar media showing that, while there is no significant effect arising from the use of enantiopure or chiral amino acids, the coordination polymers exert an appreciable antimicrobial activity comparable, when not superior, to that of the metal salts alone.


Assuntos
Anti-Infecciosos , Complexos de Coordenação , Nitrato de Prata/farmacologia , Histidina , Cobre/farmacologia , Cobre/química , Polímeros/farmacologia , Polímeros/química , Sais , Cristalografia por Raios X , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Arginina/farmacologia , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química
5.
BMC Plant Biol ; 22(1): 323, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35790925

RESUMO

The application of nanotechnology in agriculture can remarkably improve the cultivation and growth of crop plants. Many studies showed that nanoparticles (NPs) made plants grow more vigorously. Light can make NPs aggregated, leading to the reduction of the NPs toxicity. In addition, treatment with NPs had a "hormesis effect" on plants. In this study, light-induced silver nanoparticles (AgNPs) were synthesized by using the alfalfa (Medicago sativa L.) extracts, and then the optimal synthetic condition was determined. Light-induced AgNPs were aggregated, spherical and pink, and they were coated with esters, phenols, acids, terpenes, amino acids and sugars, which were the compositions of alfalfa extracts. The concentration of free Ag+ was less than 2 % of the AgNPs concentration. Through nanopriming, Ag+ got into the seedlings and caused the impact of AgNPs on alfalfa. Compared with the control group, low concentration of light-induced AgNPs had a positive effect on the photosynthesis. It was also harmless to the leaf cells, and there was no elongation effect on shoots. Although high concentration of AgNPs was especially beneficial to root elongation, it had a slight toxic effect on seedlings due to the accumulation of silver. With the increase of AgNPs concentration, the content of silver in the seedlings increased and the silver enriched in plants was at the mg/kg level. Just as available research reported the toxicity of NPs can be reduced by using suitable synthesis and application methods, the present light induction, active material encapsulation and nanopriming minimized the toxicity of AgNPs to plants, enhancing the antioxidant enzyme system.


Assuntos
Nanopartículas Metálicas , Prata , Medicago sativa/metabolismo , Nanopartículas Metálicas/química , Plântula/metabolismo , Prata/química , Nitrato de Prata/farmacologia
6.
J Antimicrob Chemother ; 77(6): 1635-1644, 2022 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-35325152

RESUMO

OBJECTIVES: Antibiotic resistance, biofilm and persistent infection of Pseudomonas aeruginosa is a perilous challenge in the healthcare system. Hence, a vast number of novel antipseudomonas approaches are currently being pursued. Our group focuses on exploring the efficacy of metal(loid)-based antimicrobials (MBAs) towards novel infection control solutions. METHODS: Initially, nine MBAs were tested for biofilm prevention and eradication efficacy. Synergistic potentials were then screened systematically in a total of 1920 combinatorial MBA concentrations, in laboratory media [CAMHB and LB] and infection-related simulated wound fluid (SWF). The antibiofilm efficacy of the silver nitrate (AgNO3; 'Ag') with potassium tellurite (K2TeO3; 'Te') combination was examined against clinical antibiotic-resistant isolates and compared with the most used antibiotics. The in vitro resistance acquisition test, for exploring the chance of getting future resistance, and meta-analysis, for estimating Ag/Te human cell cytotoxicity, were carried out. RESULTS: The Ag/Te combination was identified as the most effective agent against P. aeruginosa biofilm. The application of the Ag/Te combination was quite effective against all clinical isolates. Comparison of clinical isolates with indicator strains showed clinical isolates are gaining resistance against the antibiotics (especially gentamicin) and Ag, while they are susceptible to Te and particularly the Ag/Te combination. The chance of getting future resistance against Ag/Te as a mixture was remarkably lower than the individual application of each metal. Te has significantly lower human cell cytotoxicity in comparison with Ag. CONCLUSIONS: Te could be an appropriate alternative against P. aeruginosa biofilms (existing or prevention thereof), especially in combination with Ag.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Humanos , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/tratamento farmacológico , Nitrato de Prata/farmacologia , Telúrio
7.
Int J Mol Sci ; 23(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35163290

RESUMO

Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials. The level of exposure to nanosilver is constantly raising, and a growing body of research highlights that it is harmful to the health, especially the nervous system, of humans. The potential pathways through which nanosilver affects neurons include the release of silver ions and the associated induction of oxidative stress. To better understand the mechanisms underlying the neurotoxicity of nanosilver, in this study we exposed male Wistar rats to 0.5 mg/kg body weight of AgNPs coated with bovine serum albumin (BSA), polyethylene glycol (PEG), or citrate, or to AgNO3 as a source of silver ions for 28 days and assessed the expression of antioxidant defense markers in the hippocampus of the exposed animals after 1 week of spatial memory training. We also evaluated the influence of AgNPs coating on neurosteroidogenesis in the rat hippocampus. The results showed that AgNPs disrupted the antioxidant system in the hippocampus and induced oxidative stress in a coating-dependent manner, which could potentially be responsible for neurodegeneration and cognitive disorders. The analysis of the influence of AgNPs on neurosteroids also indicated coating-dependent modulation of steroid levels with a significant decrease in the concentrations of progesterone and 17α-progesterone in AgNPs(BSA), AgNPs(PEG), and Ag+ groups. Furthermore, exposure to AgNPs or Ag+ resulted in the downregulation of selected genes involved in antioxidant defense (Cat), neurosteroid synthesis (Star, Hsd3b3, Hsd17b1, and Hsd17b10), and steroid metabolism (Ar, Er1, and Er2). In conclusion, depending on the coating material used for their stabilization, AgNPs induced oxidative stress and modulated the concentrations of steroids as well as the expression of genes involved in steroid synthesis and metabolism.


Assuntos
Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Antioxidantes/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Ácido Cítrico/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Nanopartículas Metálicas/química , Modelos Animais , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Polietilenoglicóis/farmacologia , Ratos , Ratos Wistar , Soroalbumina Bovina/farmacologia , Prata/química , Nitrato de Prata/farmacologia
8.
Prep Biochem Biotechnol ; 52(1): 99-107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33890844

RESUMO

The objective of this study is to synthesize neem-silver nitrate nanoparticles (neem-AgNPs) using aqueous extracts of Azadirachta indica A. Juss for malaria therapy. Neem leaves collected from FRIM Malaysia were authenticated and extracted using Soxhlet extraction method. The extract was introduced to 1 mM of silver nitrate solution for neem-AgNPs synthesis. Synthesized AgNPs were further characterized by ultraviolet-visible spectroscopy and the electron-scanning microscopy. Meanwhile, for the anti-plasmodial activity of the neem-AgNPs, two lab-adapted Plasmodium falciparum strains, 3D7 (chloroquine-sensitive), and W2 (chloroquine-resistant) were tested. Red blood cells hemolysis was monitored to observe the effects of neem-AgNPs on normal and parasitized red blood cells. The synthesized neem-AgNPs were spherical in shape and showed a diameter range from 31-43 nm. When compared to aqueous neem leaves extract, the half inhibitory concentration (IC50) of the synthesized neem-AgNPs showed a four-fold IC50 decrease against both parasite strains with IC50 value of 40.920 µg/mL to 8.815 µg/mL for 3D7, and IC50 value of 98.770 µg/mL to 23.110 µg/mL on W2 strain. The hemolysis assay indicates that the synthesized neem-AgNPs and aqueous extract alone do not have hemolysis activity against normal and parasitized red blood cells. Therefore, this study shows the synthesized neem-AgNPs has a great potential to be used for malaria therapy.


Assuntos
Antimaláricos/química , Azadirachta/química , Extratos Vegetais/química , Nitrato de Prata/química , Antimaláricos/síntese química , Antimaláricos/farmacologia , Química Verde , Humanos , Malária Falciparum/tratamento farmacológico , Nanopartículas/química , Plasmodium falciparum/efeitos dos fármacos , Nitrato de Prata/síntese química , Nitrato de Prata/farmacologia
9.
Molecules ; 27(19)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36234841

RESUMO

Silver nanoparticles (AgNPs) have recently gained interest in the medical field because of their biological features. The present study aimed at screening Rhizophora apiculata secondary metabolites, quantifying their flavonoids and total phenolics content, green synthesis and characterization of R. apiculata silver nanoparticles. In addition, an assessment of in vitro cytotoxic, antioxidant, anti-inflammatory and wound healing activity of R. apiculata and its synthesized AgNPs was carried out. The powdered plant material (leaves) was subjected to Soxhlet extraction to obtain R. apiculata aqueous extract. The R. apiculata extract was used as a reducing agent in synthesizing AgNPs from silver nitrate. The synthesized AgNPs were characterized by UV-Vis, SEM-EDX, XRD, FTIR, particle size analyzer and zeta potential. Further aqueous leaf extract of R. apiculata and AgNPs was subjected for in vitro antioxidant, anti-inflammatory, wound healing and cytotoxic activity against A375 (Skin cancer), A549 (Lung cancer), and KB-3-1 (Oral cancer) cell lines. All experiments were repeated three times (n = 3), and the results were given as the mean ± SEM. The flavonoids and total phenolics content in R. apiculata extract were 44.18 ± 0.086 mg/g of quercetin and 53.24 ± 0.028 mg/g of gallic acid, respectively. SEM analysis revealed R. apiculata AgNPs with diameters ranging from 35 to 100 nm. XRD confirmed that the synthesized silver nanoparticles were crystalline in nature. The cytotoxicity cell viability assay revealed that the AgNPs were less toxic (IC50 105.5 µg/mL) compared to the R. apiculata extract (IC50 47.47 µg/mL) against the non-cancerous fibroblast L929 cell line. Antioxidant, anti-inflammatory, and cytotoxicity tests revealed that AgNPs had significantly more activity than the plant extract. The AgNPs inhibited protein denaturation by a mean percentage of 71.65%, which was equivalent to the standard anti-inflammatory medication diclofenac (94.24%). The AgNPs showed considerable cytotoxic effect, and the percentage of cell viability against skin cancer, lung cancer, and oral cancer cell lines was 31.84%, 56.09% and 22.59%, respectively. R. apiculata AgNPs demonstrated stronger cell migration and percentage of wound closure (82.79%) compared to the plant extract (75.23%). The overall results revealed that R. apiculata AgNPs exhibited potential antioxidant, anti-inflammatory, wound healing, and cytotoxic properties. In future, R. apiculata should be further explored to unmask its therapeutic potential and the mechanistic pathways of AgNPs should be studied in detail in in vivo animal models.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Neoplasias Bucais , Rhizophoraceae , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Diclofenaco/farmacologia , Ácido Gálico/farmacologia , Nanopartículas Metálicas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Quercetina/farmacologia , Substâncias Redutoras/farmacologia , Prata/farmacologia , Nitrato de Prata/farmacologia , Cicatrização
10.
Molecules ; 26(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34641304

RESUMO

The current research work illustrates an economical and rapid approach towards the biogenic synthesis of silver nanoparticles using aqueous Punica granatum leaves extract (PGL-AgNPs). The optimization of major parameters involved in the biosynthesis process was done using Box-Behnken Design (BBD). The effects of different independent variables (parameters), namely concentration of AgNO3, temperature and ratio of extract to AgNO3, on response viz. particle size and polydispersity index were analyzed. As a result of experiment designing, 17 reactions were generated, which were further validated experimentally. The statistical and mathematical approaches were employed on these reactions in order to interpret the relationship between the factors and responses. The biosynthesized nanoparticles were initially characterized by UV-vis spectrophotometry followed by physicochemical analysis for determination of particle size, polydispersity index and zeta potential via dynamic light scattering (DLS), SEM and EDX studies. Moreover, the determination of the functional group present in the leaves extract and PGL-AgNPs was done by FTIR. Antibacterial and antibiofilm efficacies of PGL-AgNPs against Gram-positive and Gram-negative bacteria were further determined. The physicochemical studies suggested that PGL-AgNPs were round in shape and of ~37.5 nm in size with uniform distribution. Our studies suggested that PGL-AgNPs exhibit potent antibacterial and antibiofilm properties.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Punica granatum/química , Nitrato de Prata/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Nitrato de Prata/química
11.
Molecules ; 26(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066875

RESUMO

The main core of wound treatment is cell growth and anti-infection. To accelerate the proliferation of fibroblasts in the wound and prevent wound infections, various strategies have been tried. It remains a challenge to obtain good cell proliferation and antibacterial effects. Here, human hair kerateine (HHK)/poly(ethylene oxide) (PEO)/poly(vinyl alcohol) (PVA) nanofibers were prepared using cysteine-rich HHK, and then, silver nanoparticles (AgNPs) were in situ anchored in the sulfur-containing amino acid residues of HHK. After the ultrasonic degradation test, HHK/PEO/PVA nanofibrous mats treated with 0.005-M silver nitrate were selected due to their relatively complete structures. It was observed by TEM-EDS that the sulfur-containing amino acids in HHK were the main anchor points of AgNPs. The results of FTIR, XRD and the thermal analysis suggested that the hydrogen bonds between PEO and PVA were broken by HHK and, further, by AgNPs. AgNPs could act as a catalyst to promote the thermal degradation reaction of PVA, PEO and HHK, which was beneficial for silver recycling and medical waste treatment. The antibacterial properties of AgNP-HHK/PEO/PVA nanofibers were examined by the disk diffusion method, and it was observed that they had potential antibacterial capability against Gram-positive bacteria, Gram-negative bacteria and fungi. In addition, HHK in the nanofibrous mats significantly improved the cell proliferation of NIH3T3 cells. These results illustrated that the AgNP-HHK/PEO/PVA nanofibrous mats exhibited excellent antibacterial activity and the ability to promote the proliferation of fibroblasts, reaching our target applications.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Proliferação de Células/efeitos dos fármacos , Queratinas Específicas do Cabelo/química , Nanopartículas Metálicas/química , Nanofibras/química , Polietilenoglicóis/química , Álcool de Polivinil/química , Prata/química , Animais , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Cabelo/química , Humanos , Ligação de Hidrogênio , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Nitrato de Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
12.
Mol Biol Rep ; 47(9): 6887-6897, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32914263

RESUMO

The objective of the present work was the selection of cultivar, suitable medium and explant type for callus, root production, ascorbic acid, total ascorbic acid, dehydroascorbic and total protein of non-heading Chinese cabbage in two cultivars 'Caixin' and 'Suzhouqing'. We compared 10 types of MS media supplemented with 0.0, 1.0, 2.0 and 3.0 mg/l TDZ; 0.0, 0.25, 0.50 and 1.0 mg/l NAA and 0.0, 5.0, 7.5 and 9.0 mg/l AgNO3 and 5 kinds of explants as embryo, leaf, root, cotyledon and hypocotyl. Maximum frequency of callus fresh weight was recorded with hypocotyl explant, which were cultured on MS + 2.0 mg/l TDZ + 1.0 mg/l NAA + 9.0 mg/l AgNO3 in 'Suzhouqing', optimum callus dry weight was obtained on the same media. The highest result for root fresh and dry weight recorded with 'Caixin' with MS + 3.0 mg/l TDZ + 1.0 mg/l NAA + 9.0 mg/l AgNO3 when we used embryo as explant. The highest ascorbic acid content was found with callus cultured on MS + 1.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3, when used leaf explant in 'Caixin' or root in 'Suzhouqing', and there were no significant difference between them. While the highest value of total AsA content was registered with callus cultured on MS + 2.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3 extracted from cotyledon in 'Caixin'. The highest content of DHA was registered with MS + 2.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3 with cotyledon in 'Caixin'. Also, in 'Caixin' MS + 3.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3 recorded the highest value of total protein content with embryo explant.


Assuntos
Ácido Ascórbico/análise , Calo Ósseo/efeitos dos fármacos , Brassica rapa/metabolismo , Técnicas de Cultura de Células/métodos , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Proteínas/análise , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/metabolismo , Calo Ósseo/crescimento & desenvolvimento , Calo Ósseo/metabolismo , Brassica rapa/crescimento & desenvolvimento , Células Cultivadas , Naftalenos/farmacologia , Compostos de Fenilureia/farmacologia , Células Vegetais/efeitos dos fármacos , Células Vegetais/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Nitrato de Prata/farmacologia , Tiadiazóis/farmacologia
13.
Plant Cell Rep ; 39(7): 921-939, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32300886

RESUMO

KEY MESSAGE: Atropa acuminata aqueous leaf extract biosynthesized silver nanoparticles showed strong antioxidant, anticancerous (HeLa cells) and anti-inflammatory activities. Besides, this bio syn-AgNP also proved effective against mosquito vectors causing malaria, dengue and filariasis. Present study highlights eco-friendly and sustainable approach for the synthesis of silver nanoparticles (AgNP) using aqueous leaf extract of A. acuminata, a critically endangered medicinal herb. The addition of 1 mM silver nitrate to aqueous leaf extract resulted in the synthesis of AgNP when solution was heated at 60 °C for 30 min at pH 7. Absorption band at 428 nm, as shown by UV-Vis spectroscopy confirmed the synthesis of AgNP. XRD patterns revealed the crystalline nature of AgNP and TEM analysis showed that most of the nanoparticles were spherical in shape. Zeta potential of AgNP was found to be - 33.5 mV which confirmed their high stability. FT-IR investigations confirmed the presence of different functional groups involved in the reduction and capping of AgNP. The synthesized AgNP showed effective DPPH (IC50-16.08 µg/mL), H2O2 (IC50-25.40 µg/mL), and superoxide (IC50-21.12 µg/mL) radical scavenging activities. These plant-AgNP showed significant inhibition of albumin denaturation (IC50-12.98 µg/mL) and antiproteinase activity (IC50-18.401 µg/mL). Besides, biosynthesized AgNP were found to have strong inhibitory effect against a cervical cancer (HeLa) cell line (IC50-5.418 µg/mL) as well as larvicidal activity against 3rd instar larvae of Anopheles stephensi (LC50-18.9 ppm, LC90-40.18 ppm), Aedes aegypti (LC50-12.395 ppm, LC90-36.34 ppm) and Culex quinquefasciatus (LC50-17.76 ppm, LC90-30.82 ppm) and were found to be non-toxic against normal cell line (HEK 293), and a non-target organism (Mesocyclops thermocyclopoides). This is the first report on the synthesis of AgNP using aqueous leaf extract of A. acuminata, validating their strong therapeutic potential.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Atropa belladonna/química , Química Verde , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Prata/farmacologia , Animais , Culicidae , Flavonoides/análise , Sequestradores de Radicais Livres/farmacologia , Células HEK293 , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Fenóis/análise , Folhas de Planta/química , Nitrato de Prata/farmacologia , Espectrofotometria Ultravioleta , Taninos/análise , Temperatura , Fatores de Tempo , Difração de Raios X
14.
Molecules ; 25(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066253

RESUMO

Plants that synthesize bioactive compounds that have high antioxidant value and elicitation offer a reliable in vitro technique to produce important nutraceutical compounds. The objective of this study is to promote the biosynthesis of these phenolic compounds on a large scale using elicitors in date palm cell suspension culture. Elicitors such as pectin, yeast extract (YE), salicylic acid (SA), cadmium chloride (CdCl2), and silver nitrate (AgNO3) at 50, 100, and 200 mg/L concentrations are used. The effects of elicitors on cell culture were determined in terms of biomass [packed cell volume (PCV), fresh and dry weight], antioxidant activity, and phenolic compounds (catechin, caffeic acid, kaempferol, apigenin) were determined using high-performance liquid chromatography (HPLC). Results revealed that enhanced PCV (12.3%), total phenolic content [317.9 ± 28.7 mg gallic acid equivalents (GAE)/100 g of dry weight (DW)], and radical scavenging activity (86.0 ± 4.5%) were obtained in the 50 mg/L SA treated cell culture of Murashige and Skoog (MS) medium. The accumulation of optimum catechin (26.6 ± 1.3 µg/g DW), caffeic acid (31.4 ± 3.8 µg/g DW), and kaempferol (13.6 ± 1.6 µg/g DW) was found in the 50 mg/L SA-treated culture when compared to the control. These outcomes could be of great importance in the nutraceutical and agronomic industries.


Assuntos
Técnicas de Cultura de Células/métodos , Fenóis/metabolismo , Phoeniceae/citologia , Phoeniceae/efeitos dos fármacos , Biomassa , Biotecnologia/métodos , Cloreto de Cádmio/farmacologia , Meios de Cultura/química , Meios de Cultura/farmacologia , Flavonoides/metabolismo , Pectinas/farmacologia , Phoeniceae/metabolismo , Ácido Salicílico/farmacologia , Nitrato de Prata/farmacologia
15.
Pak J Pharm Sci ; 33(3): 937-945, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33191216

RESUMO

The majority of the world population suffers from mental and behavioral disorder. It is the need of the time to find an alternate of presently available medicines in order to decrease the medical expense. Homeopathic remedies are available and prescribed by homeopaths for treatment of anxiety and depression. Unfortunately, no data are available that proves its potential to relieve mental illness. The current study is designed to assess neuro behavioral and antidepressant like effects of homeopathic remedies Staphysagria, Argentum nitricum and Ignatia amara in comparison with standard drug (escitalopram). Different neuro behavioral activities were analyzed. The animals were administered the doses of all homeopathic remedied (60 µl to the rats) and escitalopram (0.042 mg to rats) through the oral route. The activities were observed on day 30th and day 60th. Our result suggests that the swimming time in Staphysagria treated group were significantly improved (p<0.001) after day 60th and significance rise was observed (p<0.01) in Ignatia amara treated animals, whereas significant decline (p<0.05) in struggling time was observed in Argentum nitricum administered animals after the 60th day as compared to 30th day. The central square crossings were improved highly significantly (p<0.001) after the 30th day dosing, by all three remedies and peripheral squares crossing were found highly significantly increased (p<0.001) after chronic dosing in Staphysagria and Ignatia amara treated groups. It is concluded from the results that all three homeopathic remedies produce comparable effects like standard drug while among all three remedies Staphysagria possess a potent antidepressant activity. To the best of our knowledge the current study reports first time the anti-depressant potential of homeopathic remedies in rodents.


Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Homeopatia , Locomoção/efeitos dos fármacos , Extratos Vegetais/farmacologia , Nitrato de Prata/farmacologia , Animais , Delphinium , Depressão/fisiopatologia , Modelos Animais de Doenças , Feminino , Masculino , Teste de Campo Aberto , Ratos , Strychnos , Natação , Fatores de Tempo
16.
BMC Genomics ; 20(1): 811, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694528

RESUMO

BACKGROUND: Drought stress is a major limiting factor of soybean [Glycine max (L.) Merr.] production around the world. Soybean plants can ameliorate this stress with improved water-saving, sustained N2 fixation during water deficits, and/or limited leaf hydraulic conductance. In this study, carbon isotope composition (δ13C), which can relate to variation in water-saving capability, was measured. Additionally, nitrogen isotope composition (δ15N) and nitrogen concentration that relate to nitrogen fixation were evaluated. Decrease in transpiration rate (DTR) of de-rooted soybean shoots in a silver nitrate (AgNO3) solution compared to deionized water under high vapor pressure deficit (VPD) conditions was used as a surrogate measurement for limited leaf hydraulic conductance. A panel of over 200 genetically diverse soybean accessions genotyped with the SoySNP50K iSelect BeadChips was evaluated for the carbon and nitrogen related traits in two field environments (Athens, GA in 2015 and 2016) and for transpiration response to AgNO3 in a growth chamber. A multiple loci linear mixed model was implemented in FarmCPU to perform genome-wide association analyses for these traits. RESULTS: Thirty two, 23, 26, and nine loci for δ13C, δ15N, nitrogen concentration, and transpiration response to AgNO3, respectively, were significantly associated with these traits. Candidate genes that relate to drought stress tolerance enhancement or response were identified near certain loci that could be targets for improving and understanding these traits. Soybean accessions with favorable breeding values were also identified. Low correlations were observed between many of the traits and the genetic loci associated with each trait were largely unique, indicating that these drought tolerance related traits are governed by different genetic loci. CONCLUSIONS: The genomic regions and germplasm identified in this study can be used by breeders to understand the genetic architecture for these traits and to improve soybean drought tolerance. Phenotyping resources needed, trait heritability, and relationship to the target environment should be considered before deciding which of these traits to ultimately employ in a specific breeding program. Potential marker-assisted selection efforts could focus on loci which explain the greatest amount of phenotypic variation for each trait, but may be challenging due to the quantitative nature of these traits.


Assuntos
Carbono/metabolismo , Estudo de Associação Genômica Ampla , Glycine max/genética , Glycine max/metabolismo , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Aquaporinas/antagonistas & inibidores , Perfilação da Expressão Gênica , Loci Gênicos/genética , Nitrato de Prata/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-30642923

RESUMO

Uropathogenic Escherichia coli (UPEC) is a frequent cause of catheter-associated urinary tract infection (CAUTI). Biocides have been incorporated into catheter coatings to inhibit bacterial colonization while, ideally, exhibiting low cytotoxicity and mitigating the selection of resistant bacterial populations. We compared the effects of long-term biocide exposure on susceptibility, biofilm formation, and relative pathogenicity in eight UPEC isolates. MICs, minimum bactericidal concentrations (MBCs), minimum biofilm eradication concentrations (MBECs), and antibiotic susceptibilities were determined before and after long-term exposure to triclosan, polyhexamethylene biguanide (PHMB), benzalkonium chloride (BAC), and silver nitrate. Biofilm formation was quantified using a crystal violet assay, and relative pathogenicity was assessed via a Galleria mellonella waxworm model. Cytotoxicity and the resulting biocompatibility index values were determined by use of an L929 murine fibroblast cell line. Biocide exposure resulted in multiple decreases in biocide susceptibility in planktonic and biofilm-associated UPEC. Triclosan exposure induced the largest frequency and magnitude of susceptibility decreases at the MIC, MBC, and MBEC, which correlated with an increase in biofilm biomass in all isolates. Induction of antibiotic cross-resistance occurred in 6/84 possible combinations of bacteria, biocide, and antibiotic. Relative pathogenicity significantly decreased after triclosan exposure (5/8 isolates), increased after silver nitrate exposure (2/8 isolates), and varied between isolates for PHMB and BAC. The biocompatibility index ranked the antiseptic potential as PHMB > triclosan > BAC > silver nitrate. Biocide exposure in UPEC may lead to reductions in biocide and antibiotic susceptibility, changes in biofilm formation, and alterations in relative pathogenicity. These data indicate the multiple consequences of biocide adaptation that should be considered when selecting an anti-infective catheter-coating agent.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Desinfetantes/farmacologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/patogenicidade , Animais , Compostos de Benzalcônio/farmacologia , Biguanidas/farmacologia , Biofilmes/crescimento & desenvolvimento , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/microbiologia , Linhagem Celular , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/tratamento farmacológico , Gentamicinas/farmacologia , Células L , Camundongos , Testes de Sensibilidade Microbiana , Mariposas/microbiologia , Nitrofurantoína/farmacologia , Nitrato de Prata/farmacologia , Triclosan/farmacologia , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Virulência/efeitos dos fármacos
18.
Anal Biochem ; 578: 36-44, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31085164

RESUMO

Considering the shortcomings related to antibiotics usage, the introduction of other bacteriostatic and bactericidal agents that present synergetic effects or standalone properties is urgently needed. AgNO3 is an important bactericidal agent, which imparts various functions on bacteria dependent on its concentration. Therefore, an understanding of its mechanisms of action in infinitesimal concentrations plays an important role which can ultimately lead to AgNO3 involvement in the pharmaceutical industry. The monitoring of VOC (volatile organic compound) profiles emitted by bacteria is a simple method to assess changes occurring in bacterial metabolism. In this study, VOCs of Hafnia alvei, Pseudomonas luteola and Staphylococcus warneri cultures were analyzed both in the absence and in the presence of three concentrations of AgNO3. Headspace solid-phase microextraction gas chromatography/mass spectrometry (HS-SPME-GC/MS) was employed for extraction and analysis. After supplementation with AgNO3, changes in the emitted fingerprints were investigated. Odorants associated with mouth-related and systemic diseases, like dimethyl trisulfide, indole (halitosis) and 2-hexanone (celiac disease), were also affected by addition of AgNO3. Statistical tests proved discrimination between obtained profiles with more that 90% variability. Moreover, physiological states of bacteria after dosage with various concentration of stressing agent were investigated and explained by the mechanisms of action.


Assuntos
Hafnia alvei/efeitos dos fármacos , Pseudomonas/efeitos dos fármacos , Saliva/microbiologia , Nitrato de Prata/farmacologia , Staphylococcus/efeitos dos fármacos , Compostos Orgânicos Voláteis/metabolismo , Humanos
19.
Chem Res Toxicol ; 32(6): 1027-1039, 2019 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-31012303

RESUMO

Pyrrolizidine alkaloids (PAs) are naturally occurring phytotoxins widely distributed in about 3% of flowering plants. The formation of PA-derived pyrrole-protein adducts is considered as a primary trigger initiating PA-induced hepatotoxicity. The present study aims to (i) further validate our previous established derivatization method using acidified ethanolic AgNO3 for the analysis of pyrrole-protein adducts and (ii) apply this method to characterize the binding tendency, dose-response, and elimination kinetics of pyrrole-protein adducts in blood samples. Two pyrrole-amino acid conjugates, (±)-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5 H-pyrrolizine (DHP)-cysteine (7-cysteine-DHP) and 9-histidine-DHP, were synthesized and used to demonstrate that acidified ethanolic AgNO3 derivatization can cleave both S-linkage and N-linkage of pyrrole-protein adducts. Subsequently, using precolumn AgNO3 derivatization followed by ultra-high-pressure liquid chromatography/mass spectrometry analysis, we quantified pyrrole-protein adducts in monocrotaline-treated rat blood protein fractions, including hemoglobin (Hb), plasma, albumin, and plasma residual protein fractions, and found that the amount of pyrrole-Hb adducts was significantly higher than that in all plasma fractions. Moreover, elimination half-life of pyrrole-Hb adducts was also significantly longer than pyrrole-protein adducts in plasma fractions (12.08 vs 2.54-2.93 days). In addition, we also tested blood samples obtained from five PA-induced liver injury patients and found that the amount of pyrrole-protein adducts in blood cells was also remarkably higher than that in plasma. In conclusion, our findings for the first time confirmed that the AgNO3 derivatization method could be used to measure both S- and N-linked pyrrole-protein adducts and also suggested that pyrrole-Hb adducts with remarkably higher level and longer life span could be a better biomarker of PA exposure.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/sangue , Hemoglobinas/análise , Pirróis/sangue , Alcaloides de Pirrolizidina/efeitos adversos , Idoso , Animais , Biomarcadores/sangue , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estrutura Molecular , Alcaloides de Pirrolizidina/administração & dosagem , Alcaloides de Pirrolizidina/metabolismo , Ratos , Ratos Sprague-Dawley , Nitrato de Prata/química , Nitrato de Prata/farmacologia
20.
Mol Pharm ; 16(7): 3011-3023, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31145852

RESUMO

Using oral cancer cells ( in vitro) and in vivo xenograft mice model, we have systematically studied the detailed mechanism of anticancer activity of quinacrine-based hybrid silver (QAgNP) and gold (QAuNP) nanoparticles (NPs) and compared their efficacies. Both the NPs showed characteristic anti-cell proliferation profile in various cancer cells with minimally affecting the normal nontransformed breast epithelial MCF-10A cells. The IC50 values of QAuNP in various cancer cells were less compared to QAgNP and also found to be the lowest (0.5 µg/mL) in SCC-9 oral cancer cells. Although both NPs caused apoptosis by increased DNA damage, arresting at S phase and simultaneously inhibiting the DNA repair activity in cells, efficacy of QAuNP was better than that of QAgNP. NPs intercalated with DNA and inhibited the topoisomerase activity in cells. Alteration in expression of cell cycle regulatory (cyclins B1, E1, A2, etc.) and replication-related (MRE11, RPA, RFC, etc.) proteins were also observed after NP exposure to the cells. Accumulation of cells resulted in extended G/M phase after prolonged exposure of QAuNP in SCC-9 cells. Interestingly, depletion of geminin and increase of Cdt-1 along with CDC-6 suggest the formation of re-replication. Recovery of body weight and reduction in tumor volume were found in NP-treated xenograft mice. Induction of Bax/Bcl-xL, PARP-1 cleavage, p53, and p21 were noted in NP-treated xenograft mice tissue samples. Thus, data suggest that NP inhibits topoisomerase activity, thereby inhibiting DNA replication and inducing re-replication, which causes S-phase arrest, DNA damage, and finally apoptosis of the oral cancer cells. Also, it was found that anticancer activity of QAuNP is better than that of QAgNP.


Assuntos
Antineoplásicos/uso terapêutico , Cloretos/química , Compostos de Ouro/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Nanopartículas/química , Quinacrina/química , Nitrato de Prata/química , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cloretos/farmacologia , Dano ao DNA/efeitos dos fármacos , Feminino , Compostos de Ouro/farmacologia , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Nitrato de Prata/farmacologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
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