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1.
Environ Monit Assess ; 196(5): 412, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565815

RESUMO

Cadmium (Cd) is a highly toxic metal that frequently contaminates our environment. In this study, the bioflocculant-producing, cadmium-resistant Escherichia fergusonii ZSF-15 was characterized from Paharang drain, Bawa Chak, Faisalabad, Pakistan. The Cd-resistant E. fergusonii was used to determine the bioflocculant production using yeast-peptone-glycerol medium (pH 6.5) supplemented with 50 mg L-1 of Cd. The culture was incubated for 3 days at 37 °C in a rotary shaker at 120 rpm. The fermentation broth was centrifuged at 4000 g for 10 min after the incubation period. The maximum flocculating activity by isolate ZSF-15 was found to be 71.4% after 48 h of incubation. According to the Fourier transform infrared spectroscopy analysis, the bioflocculant produced by strain ZSF-15 was comprised of typical polysaccharide and protein, i.e. hydroxyl, carboxyl, and amino groups. The strain ZSF-15 exhibited bioflocculant activity at range of pH (6-8) and temperature (35-50℃). Maximum flocculation activity (i.e. 71%) was observed at 47℃, whereas 63% flocculation production was observed at pH 8. In the present study, antioxidant enzyme profile of ZSF-15 was also evaluated under cadmium stress. A significant increase in antioxidant enzymes including superoxide dismutase (118%) and ascorbate peroxidase (28%) was observed, whereas contents of catalase (86%), glutathione transferase (13%), and peroxidase (8%) were decreased as compared to control.


Assuntos
Antioxidantes , Cádmio , Escherichia , Cádmio/toxicidade , Concentração de Íons de Hidrogênio , Monitoramento Ambiental , Floculação
2.
Molecules ; 28(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36677768

RESUMO

The delayed healing of wounds among people with diabetes is a severe problem worldwide. Hyperglycemia and increased levels of free radicals are the major inhibiting factors of wound healing in diabetic patients. Plant extracts are a rich source of polyphenols, allowing them to be an effective agent for wound healing. Drying temperature and extraction solvent highly affect the stability of polyphenols in plant materials. However, there is a need to optimize the extraction protocol to ensure the efficacy of the final product. For this purpose, the effects of drying temperature and solvents on the polyphenolic composition and diabetic wound healing activity of Moringa oleifera leaves were examined in the present research. Fresh leaves were oven dried at different temperatures (10 °C, 30 °C, 50 °C, and 100 °C) and extracted in three solvents (acetone, ethanol, and methanol) to obtain twelve extracts in total. The extracts were assessed for free radical scavenging and antihyperglycemic effects using DPPH (2,2-diphenylpicrylhydrazyl) and α- glucosidase inhibition assays. Alongside this, a scratch assay was performed to evaluate the cell migration activity of M. oleifera on the human retinal pigment epithelial cell line. The cytotoxicity of the plant extracts was assessed on human retinal pigment epithelial (RPE) and hepatocellular carcinoma (Huh-7) cell lines. Using high-performance liquid chromatography, phenolic compounds in extracts of M. oleifera were identified. We found that an ethanol-based extract prepared by drying the leaves at 10 °C contained the highest amounts of identified polyphenols. Moringa oleifera extracts showed remarkable antioxidant, antidiabetic, and cell migration properties. The best results were obtained with leaves dried at 10 °C and 30 °C. Decreased activities were observed with drying temperatures of 50 °C and above. Moreover, M. oleifera extracts exhibited no toxicity on RPE cells, and the same extracts were cytotoxic for Huh-7 cells. This study revealed that M. oleifera leaves extracts can enhance wound healing in diabetic conditions due to their antihyperglycemic, antioxidant, and cell migration effects. The leaves of this plant can be an excellent therapeutic option when extracted at optimum conditions.


Assuntos
Diabetes Mellitus , Moringa oleifera , Humanos , Antioxidantes/farmacologia , Antioxidantes/análise , Solventes , Moringa oleifera/química , Temperatura , Polifenóis/farmacologia , Polifenóis/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Cicatrização , Hipoglicemiantes/farmacologia , Etanol , Folhas de Planta/química
3.
Molecules ; 28(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37110702

RESUMO

As is well known, plant products have been increasingly utilized in the pharmaceutical industry in recent years. By combining conventional techniques and modern methodology, the future of phytomedicines appears promising. Pogostemon Cablin (patchouli) is an important herb used frequently in the fragrance industries and has various therapeutic benefits. Traditional medicine has long used the essential oil of patchouli (P. cablin) as a flavoring agent recognized by the FDA. This is a gold mine for battling pathogens in China and India. In recent years, this plant has seen a significant surge in use, and approximately 90% of the world's patchouli oil is produced by Indonesia. In traditional therapies, it is used for the treatment of colds, fever, vomiting, headaches, and stomachaches. Patchouli oil is used in curing many diseases and in aromatherapy to treat depression and stress, soothe nerves, regulate appetite, and enhance sexual attraction. More than 140 substances, including alcohols, terpenoids, flavonoids, organic acids, phytosterols, lignins, aldehydes, alkaloids, and glycosides, have been identified in P. cablin. Pachypodol (C18H16O7) is an important bioactive compound found in P. cablin. Pachypodol (C18H16O7) and many other biologically essential chemicals have been separated from the leaves of P. cablin and many other medicinally significant plants using repeated column chromatography on silica gel. Pachypodol's bioactive potential has been shown by a variety of assays and methodologies. It has been found to have a number of biological activities, including anti-inflammatory, antioxidant, anti-mutagenic, antimicrobial, antidepressant, anticancer, antiemetic, antiviral, and cytotoxic ones. The current study, which is based on the currently available scientific literature, intends to close the knowledge gap regarding the pharmacological effects of patchouli essential oil and pachypodol, a key bioactive molecule found in this plant.


Assuntos
Óleos Voláteis , Plantas Medicinais , Pogostemon , Quercetina , Óleos Voláteis/farmacologia , Óleos Voláteis/química
4.
J Basic Microbiol ; 62(9): 1125-1142, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34747529

RESUMO

The wide diversity of cyanobacterial species and their role in a variety of biological activities have been reported in the previous few years. Cyanobacteria, especially from marine sources, constitutes a major source of biologically active metabolites that have gained great attention especially due to their anticancer potential. Numerous chemically diverse metabolites from various cyanobacterial species have been recognized to inhibit the growth and progression of tumor cells through the induction of apoptosis in many different types of cancers. These metabolites activate the apoptosis in the cancer cells by different molecular mechanisms, however, the dysregulation of the mitochondrial pathway, death receptors signaling pathways, and the activation of several caspases are the crucial mechanisms that got considerable interest. The array of metabolites and the range of mechanisms involved may also help to overcome the resistance acquired by the different tumor types against the ongoing therapeutic agents. Therefore, the primary or secondary metabolites from the cyanobacteria as well as their synthetic derivates could be used to develop novel anticancer drugs alone or in combination with other chemotherapeutic agents. In this study, we have discussed the role of cyanobacterial metabolites in the induction of cytotoxicity and the potential to inhibit the growth of cancer cells through the induction of apoptosis, cell signaling alteration, oxidative damage, and mitochondrial dysfunctions. Moreover, the various metabolites produced by cyanobacteria have been summarized with their anticancer mechanisms. Furthermore, the ongoing trials and future developments for the therapeutic implications of these compounds in cancer therapy have been discussed.


Assuntos
Antineoplásicos , Cianobactérias , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Cianobactérias/metabolismo , Neoplasias/tratamento farmacológico
5.
Drug Dev Ind Pharm ; 48(9): 502-509, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36191015

RESUMO

The worldwide increase of multi-drug resistance has directed the researchers to focus on ecofriendly ways of nanoparticles synthesis with effective antivirulence properties. Here, we report the antibiofilm and quorum quenching (QQ) potential of zirconium oxide nanoparticles (ZrO2 NPs) synthesized from aqueous ginger extract against multi-drug resistant (MDR) Acinetobacter baumannii. The results indicated that ZrO2 NPs were of tetragonal shape with average diameter of 16 nm. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for A. baumannii were 15.6 and 62.5 µg/ml, respectively, as revealed by broth microdilution assay. Exposure of bacterial cells to ZrO2 NPs resulted in reactive oxygen species (ROS) generation which in turn led to cellular membrane disruption as observed by an increase in leakage of cellular contents, such as proteins, sugars, and DNA. The antibiofilm activity was evaluated by microtiter plate assay and the results revealed that the percentage inhibition of biofilm was found to be 14.3-80.6%. ZrO2 NPs also obstructed the chemical composition of biofilms matrix by reducing the proteins and carbohydrate contents. Molecular docking studies of ZrO2 NPs with four proteins (2NAZ, 4HKG, 5D6H, and 5HM6) involved in biofilm formation of A. baumannii revealed the interaction of zirconium with target proteins. These findings suggested the in vitro efficacy of phytosynthesized ZrO2 NPs as antibiofilm and QQ agents that can be exploited in the development of alternative therapeutic options against MDR A. baumannii.


Assuntos
Acinetobacter baumannii , Nanopartículas Metálicas , Nanopartículas , Percepção de Quorum , Zircônio/farmacologia , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Biofilmes , Nanopartículas Metálicas/química
6.
Molecules ; 27(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36234800

RESUMO

Coronopus didymus (Brassicaceae) commonly known as lesser swine cress has been reported to be used for its pharmacological activities. This study aimed to evaluate the medicinal potential of C. didymus extracts against cancer, diabetes, infectious bacteria and oxidative stress and the identification of bioactive compounds present in these extracts. The effects of using different solvents for the extraction of C. didymus on the contents of major polyphenols and biological activities were investigated. Plant sample was shade dried, ground to a fine powder, and then soaked in pure acetone, ethanol and methanol. The highest contents of major polyphenols were found in methanol-based extract, i.e., chlorogenic acid, HB acid, kaempferol, ferulic acid, quercetin and benzoic acid with 305.02, 12.42, 11.5, 23.33, 975.7 and 428 mg/g of dry weight, respectively, followed by ethanol- and acetone-based extracts. The methanol-based extract also resulted in the highest antioxidant activities (56.76%), whereas the highest antiproliferative (76.36) and alpha glucosidase inhabitation (96.65) were demonstrated in ethanol-based extracts. No antibacterial property of C. didymus was observed against all the tested strains of bacteria. Further studies should be focused on the identification of specific bioactive compounds responsible for pharmacological activities.


Assuntos
Brassicaceae , Lepidium , Acetona , Animais , Antioxidantes/farmacologia , Ácido Benzoico , Ácido Clorogênico , Etanol , Hipoglicemiantes/farmacologia , Quempferóis , Metanol , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Pós , Quercetina , Solventes , Suínos , alfa-Glucosidases
7.
Can J Infect Dis Med Microbiol ; 2021: 5570963, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34876946

RESUMO

BACKGROUND: The term "persisters" refers to a small bacterial population that persists during treatment with high antibiotic concentration or dose in the absence of genetic resistance. The present study was designed to investigate the transcriptional response in indigenous Klebsiella pneumoniae under the ciprofloxacin stress. METHODS: Isolation and identification of K. pneumoniae were carried out through standard microbiological protocols. The characterization of quinolone resistance was performed by estimating the quinolone susceptibility testing, MIC estimation, and detecting the QRDR and PMQR. Transcriptional response of the isolates to ciprofloxacin was determined using qPCR. RESULTS: Among 34 isolates, 23 (67%) were resistant to ciprofloxacin. Both QRDR (gyrA and gyrB) and PMQR (qnrA, qnrB, and qnrS) were detected in the isolates, and all were found resistant to ciprofloxacin. The mRNA levels of both mutS and euTu under the influence of ciprofloxacin were significantly increased. On ciprofloxacin exposure, the mRNA levels of the DNA damage response element (mutS) were raised in a time-dependent fashion. K. pneumoniae showed high-level resistance to ciprofloxacin in the presence of mutations in QRDR and PMQR genes. CONCLUSION: The transcriptional response revealed the upregulation of DNA repair and protein folding elements (mutS and euTu) in ciprofloxacin stress and delayed cell division. The ciprofloxacin was found to trigger various stress responses in a time- and concentration-dependent manner.

8.
Pak J Pharm Sci ; 34(1(Supplementary)): 237-243, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34275847

RESUMO

Carbapenem resistance in Pseudomonas aeruginosa is a major concern in the public health sector, primarily in developing countries such as Pakistan. Therefore, novel approaches such as Silver nanoparticles (AgNPs) can be used to address emerging concerns. Clinical isolates (n=200) were reconfirmed using selective media and API 20NE kit. The antibiogram was determined according to the CLSI 2016 guidelines. Molecular detection was carried out by PCR. Antibacterial activity in AgNPs was achieved by dilution method. Of 200 P. aeruginosa, mostly (n=82; 41%) were isolated from pus samples. Of 110 MDR P. aeruginosa, 70 (63%) were carbapenemase and 58 (52%) were MBL producers. Antimicrobial profile of MBL producing P. aeruginosa reported that all isolates were resistant to ß-lactams, and 89% to levofloxacin and ciprofloxacin except colistin. Of 25 (35.7%) blaNDM producing P. aeruginosa, 12 isolates (48%) had MIC 16µg/mL to imipenem. Of 23 (32%) blaVIM producing P. aeruginosa, 12 (52%) contained MIC 16µg/mL to imipenem. However, 12 (17.1%) blaOXA-48 producing P. aeruginosa, 4 (33%) contained MIC 16µg/mL to imipenem. In vitro AgNPs activity inhibited and killed MBL producing isolates at 1 mg/mL and 2 mg/mL, respectively. AgNPs may be used as an alternative therapy followed by multiple clinical trials.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/farmacologia , Resistência beta-Lactâmica , beta-Lactamases/metabolismo , Proteínas de Bactérias/metabolismo , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana , Humanos , Levofloxacino/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/fisiologia
9.
Pak J Pharm Sci ; 34(6(Supplementary)): 2303-2308, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35039267

RESUMO

In this cross-sectional study, the isolation and identification of Methicillin Resistant Staphylococcus aureus (MRSA) and Methicillin Resistant S. epidermidis (MRSE) was described from skin infections (n=100). Initial isolation was done by conventional procedures followed by amplification/ sequence analysis of 16S rRNA. Methicillin resistance was determined using cefoxitin discs and resistant isolates were screened for mec-A gene followed by Minimum Inhibitory Concentrations (MIC) determination of vancomycin. In second phase, we investigated extract of Azadirachta indica leaves using Fourier Transformed Infrared Spectroscopy (FTIR-Spectroscopy) and investigated in vitro activity. Initially, total of 28 Staphylococci were identified. 16S rRNA gene sequence confirmed S. aureus (22), S. epidermidis (3) and S. saprophyticus (3) isolates. Cefoxitin discs showed (7/22) MRSA, (3/3) (MRSE) and none of the methicillin resistant S. saprophyticus. MRSA and MRSE isolates showed presence of mec-A gene. However, all isolates were sensitive to vancomycin MIC (0.5-2µg/mL) and sensitive to Linezolid. FTIR-Spectroscopy of A. indica indicated the presence of azadirachtin and nimbolinin. The mean zone of inhibition was measured 14.23±1.37 and 13.66±0.70 against MRSA and MRSE isolates, respectively. Altogether, MRSA and MRSE is significant public health concern. However, vancomycin and linezolid were found effective and extract of A. indica showed in vitro effects.


Assuntos
Antibacterianos/farmacologia , Azadirachta , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Staphylococcus epidermidis/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Azadirachta/química , Estudos Transversais , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Infecções Cutâneas Estafilocócicas/microbiologia , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/isolamento & purificação
10.
Arch Microbiol ; 202(5): 967-981, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32052094

RESUMO

L-asparaginase (E.C.3.5.1.1) is an important enzyme that has been purified and characterized for over decades to study and evaluate its anti-carcinogenic activity against different lymphoproliferative disorders such as acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma. The ability of the enzyme to convert L-asparagine into aspartic acid and ammonia is the reason behind its anti-cancerous activity. Apart from its medicinal uses, it is widely used in food industry to tackle acrylamide, a probable human carcinogen and, production in carbohydrate-rich foods cooked at high temperatures. There are variety of organisms including microorganisms such as bacteria, fungi, algae, and plants that produce L-asparaginase. The enzyme obtained from different microbial and plant sources have different physiochemical properties and kinetic parameters. L-asparaginases have an optimum pH range between 6 and 10 and an optimum temperature between 37 and 85 °C. This article has reviewed the lowest molecular mass for L-asparaginase in Yersinia pseudotuberculosis Q66CJ2 which is 36.27 kDa, while the highest for Pseudomonas otitidis which has a molecular mass of 205 ± 3 kDa. This review is an attempt to summarize most of the available sources, their phylogenetic relationships, purification methods, data regarding different physiochemical and kinetic properties of L-asparaginase.


Assuntos
Asparaginase/química , Bactérias/enzimologia , Fungos/enzimologia , Doença de Hodgkin/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Amônia/metabolismo , Asparaginase/genética , Asparaginase/isolamento & purificação , Asparagina/química , Ácido Aspártico/metabolismo , Humanos , Filogenia , Plantas
11.
Biofouling ; 36(4): 492-504, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32529892

RESUMO

Acinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al2O3 NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10 nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al2O3 NPs ranged between 125 and 1,000 µg ml-1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al2O3 NPs up to a concentrations of 120 µg ml-1 in HeLa cell lines. These results demonstrate an effective and safer use of Al2O3 NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production.


Assuntos
Acinetobacter baumannii , Óxido de Alumínio/toxicidade , Biofilmes/efeitos dos fármacos , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Nanopartículas/toxicidade , Antibacterianos , Biofilmes/crescimento & desenvolvimento , Células HeLa , Humanos , Testes de Sensibilidade Microbiana
12.
Environ Monit Assess ; 191(8): 490, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31297613

RESUMO

Eukaryotes employ various mechanisms to survive environmental stress conditions. Multicellular organisms eliminate permanently damaged cells by apoptosis, while unicellular eukaryotes like yeast react by decelerating cell aging. In the present study, transcriptomic and proteomic approaches were employed to elucidate the underlying mechanism of delayed apoptosis. Our findings suggest that Candida tropicalis 3Aer has a set of tightly controlled genes that are activated under Cd+2 exposition. Acute exposure to Cd+2 halts the cell cycle at the G2/M phase checkpoint and activates multiple cytoplasmic proteins that overcome effects of Cd+2-induced reactive oxygen species. Prolonged Cd+2 stress damages DNA and initiates GAPDH amyloid formation. This is the first report that Cd+2 challenge initiates dynamic redistribution of GAPDH and MDH and alters various metabolic pathways including the pentose phosphate pathway. In conclusion, the intracellular redistribution of GAPDH and MDH induced by prolonged cadmium stress modulates various cellular reactions, which facilitate delayed aging in the yeast cell.


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Candida tropicalis/efeitos dos fármacos , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Malato Desidrogenase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Candida tropicalis/metabolismo , Ciclo Celular/efeitos dos fármacos , Proteômica , Fatores de Tempo
13.
Pak J Pharm Sci ; 32(3 (Supplementary)): 1215-1218, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31303593

RESUMO

In this cross sectional study (June 2016 to June 2017), we studied the isolation and molecular characterization of multi-drug resistant Escherichia coli (MDR-E. coli) from children suffering from diarrhea. For this purpose, a total of 100 fecal samples were collected with the consent of the parents/ guardians on a prescribed form. The bacterial isolation was done by employing conventional and standard microbiological procedures. Subsequently, all the isolates were identified on the basis of biochemical tests and were further characterized by amplification of 16S rRNA gene followed by di-deoxy sequencing of the amplified product. Afterwards, the isolates were subjected to antimicrobial susceptibility profiling using Kirby Bauer disc diffusion method. A total of 87 E. coli isolates were identified in the current study and majority of the isolates were found sensitive to all or few antimicrobials. However, 14 E. coli isolates were found resistance to multiple drugs including amoxicillin-clavulanic acid, ciprofloxacin, gentamicin, cefoperazone and ofloxacin, hence termed as MDR-E. coli. All of the 14 isolates were further analyzed for the identification of blaCTX-M and blaTEM genes through PCR using specific primers. This resistant was found to be associated with the presence of plasmid encoded beta lactamases genes including blaCTX-M (13/14 E. coli isolates) and blaTEM (9/14 E. coli isolates). Altogether, it was found that ESBLs harboring E. coli is potential source of diarrhea among pediatric diarrheal patients. Therefore, molecular identification and characterization of bacterial pathogens along with antimicrobial susceptibility are critical to understand MDR- E. coli infections.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli Enteropatogênica/efeitos dos fármacos , Escherichia coli Enteropatogênica/genética , Infecções por Escherichia coli/microbiologia , beta-Lactamases/genética , Pré-Escolar , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Escherichia coli Enteropatogênica/isolamento & purificação , Proteínas de Escherichia coli/genética , Fezes/microbiologia , Humanos , Lactente , Testes de Sensibilidade Microbiana , Paquistão , Filogenia
14.
Microbiol Immunol ; 62(4): 211-220, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29405384

RESUMO

The aim of the current investigation was to determine the antibacterial and antibiofilm potential of MgO nanoparticles (NPs) against antibiotic-resistant clinical strains of bacteria. MgO NPs were synthesized by a wet chemical method and further characterized by scanning electron microscopy and energy dispersive X-ray. Antibacterial activity was determined by broth microdilution and agar diffusion methods. The Bradford method was used to assess cellular protein leakage as a result of loss of membrane integrity. Microtiter plate assay following crystal violet staining was employed to determine the effect of MgO NPs on biofilm formation and removal of established biofilms. MIC values ranged between 125 and 500 µg/mL. Moreover, treatment with MgO NPs accelerated rate of membrane disruption, measured as a function of leakage of cellular proteins. Leakage of cellular protein content was greater among gram-negative bacteria. Cell adherence assay indicated 25.3-49.8% inhibition of bacterial attachment to plastic surfaces. According to a static biofilm method, MgO NPs reduced biofilm formation potential from 31% to 82.9% in a time-dependent manner. Moreover, NPs also significantly reduced the biomass of 48, 72, 96 and 120 hr old biofilms (P < 0.05). Cytotoxicity experiments using a neutral red assay revealed that MgO NPs are non-toxic to HeLa cells at concentrations of 15-120 µg/mL. These data provide in vitro scientific evidence that MgO NPs are effective and safe antibiofilm agents that inhibit adhesion, biofilm formation and removal of established biofilms of multidrug-resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Óxido de Magnésio/farmacologia , Nanopartículas/química , Biofilmes/crescimento & desenvolvimento , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HeLa/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Fatores de Tempo
15.
Pak J Pharm Sci ; 31(6 (Supplementary): 2673-2677, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30587478

RESUMO

Metallo-ß-lactamases (MBLs) producing Pseudomonas aeruginosa are major threat for public health. They produce resistance against various antibiotics and remain low or no therapeutic options. A total of 200 clinical isolates of P. aeruginosa were collected from tertiary care hospital, Faisalabad. Isolates were sub-cultured on basic and selective media and confirmed by API 20NE. Phenotypic detection of carbapenamase, MBLs, antibiogram and MIC were determined as per CLSI guidelines. Molecular detection of blaVIM was performed using specific primers by PCR. Among 200 P. aeruginosa, majority (n=82) were isolated from pus samples followed by 28 from tracheal aspirates and 27 from sputum. Out of 110 (55%) MDR P. aeruginosa, 12 (11%) were positive for MHT and MBLs and blaVIM was identified in MBL positive isolates. Antibiogram revealed that all the isolates were resistant to ß-lactam drugs including carbapenems followed by 95% to levofloxacin, 67% to doxycycline and more effective drugs were tigecycline and colistin. MIC value for imipenem drug was 16µg/mL and 8µg/mL against 6 and 5 isolates respectively while MIC value for meropenem against 6 and 3 isolates were 8µg/mL and 16µg/mL respectively. Our study concluded the high prevalence of blaVIM producing P. aeruginosa in our clinical settings.


Assuntos
Pseudomonas aeruginosa/isolamento & purificação , Centros de Atenção Terciária/tendências , beta-Lactamases/isolamento & purificação , Antibacterianos/farmacologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Paquistão/epidemiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , beta-Lactamases/efeitos dos fármacos , beta-Lactamases/fisiologia
16.
Heliyon ; 10(8): e29500, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38660254

RESUMO

The emergence of antimicrobial resistance among biofilm forming pathogens aimed to search for the efficient and novel alternative strategies. Metallic nanoparticles have drawn a considerable attention because of their significant applications in various fields. Numerous methods are developed for the generation of these nanoparticles however, mycogenic (fungal-mediated) synthesis is attractive due to high yields, easier handling, eco-friendly and being energy efficient when compared with conventional physico-chemical methods. Moreover, mycogenic synthesis provides fungal derived biomolecules that coat the nanoparticles thus improving their stability. The process of mycogenic synthesis can be extracellular or intracellular depending on the fungal genera used and various factors such as temperature, pH, biomass concentration and cultivation time may influence the synthesis process. This review focuses on the synthesis of metallic nanoparticles by using fungal mycelium, mechanism of synthesis, factors affecting the mycosynthesis and also describes their potential applications as antioxidants and antibiofilm agents. Moreover, the utilization of mycogenic nanoparticles as quorum quenching agent in hampering the bacterial cell-cell communication (quorum sensing) has also been discussed.

17.
Int J Biol Macromol ; 242(Pt 3): 124954, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37211075

RESUMO

Biopolymer based metal oxide nanoparticles, prepared by eco-friendly approach, are gaining interest owing to their wide range of applications. In this study, aqueous extract of Trianthema portulacastrum was used for the green synthesis of chitosan base copper oxide (CH-CuO) nanoparticles. The nanoparticles were characterized through UV-Vis Spectrophotometry, SEM, TEM, FTIR and XRD analysis. These techniques provided evidence for the successful synthesis of the nanoparticles, having poly-dispersed spherical shaped morphology with average crystallite size of 17.37 nm. The antibacterial activity for the CH-CuO nanoparticles was determined against multi-drug resistant (MDR), Escherichia coli, Pseudomonas aeruginosa (gram-negative), Enterococcus faecium and Staphylococcus aureus (gram-positive). Maximum activity was obtained against Escherichia coli (24 ± 1.99 mm) while least activity was observed against Staphylococcus aureus (17 ± 1.54 mm). In-vitro analysis for biofilm inhibition, EPS and cell surface hydrophobicity showed >60 % inhibitions for all the bacterial isolates. Antioxidant and photocatalytic assays for the nanoparticles showed significant activities of radical scavenging (81 ± 4.32 %) and dye degradation (88 %), respectively. Antidiabetic activity for the nanoparticles, determined by in-vitro analysis of alpha amylase inhibition, showed enzyme inhibition of 47 ± 3.29 %. The study signifies the potential of CH-CuO nanoparticle as an effective antimicrobial agent against MDR bacteria along with the antidiabetic and photocatalytic activities.


Assuntos
Aizoaceae , Anti-Infecciosos , Quitosana , Nanopartículas Metálicas , Antioxidantes/farmacologia , Cobre/farmacologia , Quitosana/farmacologia , Hipoglicemiantes/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Bactérias , Óxidos/farmacologia , Escherichia coli , Testes de Sensibilidade Microbiana
18.
PeerJ ; 11: e14754, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778156

RESUMO

Fusarium cotton wilt is a devastating disease of the cotton crop throughout the world, caused by Fusarium oxysporum f.sp. vasinfectum (FOV). Chemical control has many side effects, so, biological controls have been widely used for the management of Fusarium wilt. This study aimed to investigate the possible use of an actinomycetes Saccharothrix algeriensis (SA) NRRL B-24137 to control FOV. To access in-vitro anti-Fusarium ability of SA NRRL B-24137, dual culture assay, spore germination and seed germination tests were carried out. Following in-vitro investigations, several pot tests in a greenhouse environment were used to evaluate the biological control potential of SA NRRL B-24137 against FOV. Dual culture assay and spore germination revealed that SA NRRL B-24137 showed significant anti-Fusarium activity.During spore germination 87.77% inhibition of spore germination were observed. In pot experiments, SA NRRL B-24137 primed cotton seeds resulted in a 74.0% reduction in disease incidence. In soil there was a significant reduction in FOV spores in the presence of SA NRRL B-24137. Positive correlation was also observed on different concentrations of SA NRRL B-24137 towards FOV reduction. The results of this study showed that SA NRRL B-24137 has the potential to be employed as a biocontrol agent against Fusarium cotton wilt, improving cotton growth characteristics and yield.


Assuntos
Fusarium , Óleo de Sementes de Algodão/farmacologia
19.
Sci Prog ; 106(4): 368504231221672, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38131108

RESUMO

Phytonanotechnology plays a crucial part in the production of good quality and high-yield food. It can also alter the plant's production systems, hence permitting the efficient, controlled and stable release of agrochemicals such as fertilizers and pesticides. An advanced understanding of nanomaterials interaction with plant responses like localization and uptake, etc. could transfigure the production of crops with high disease resistance and efficient nutrients utilization. In agriculture, the use of nanomaterials has gained acceptance due to their wide-range applications. However, their toxicity and bioavailability are the major hurdles for their massive employment. Undoubtedly, nanoparticles positively influence seeds germination, growth and development, stress management and post-harvest handling of vegetables and fruits. These nanoparticles may also cause toxicity in plants through oxidative stress by generation of excessive reactive oxygen species thus affecting the cellular biomolecules and targeting different channels. Nanoparticles have shown to exert various effects on plants that are mainly affected by various attributes such as physicochemical features of nanomaterials, coating materials for nanoparticles, type of plant, growth stages and growth medium for plants. This article discusses the interaction, accretion and toxicity of nanomaterials in plants. The factors inducing nanotoxicity and the mechanisms followed by nanomaterials causing toxicity are also instructed. At the end, detoxification mechanism of plant is also presented.


Assuntos
Nanopartículas , Nanoestruturas , Praguicidas , Nanoestruturas/toxicidade , Agricultura , Praguicidas/toxicidade , Nanopartículas/toxicidade , Nanopartículas/química , Plantas
20.
Front Microbiol ; 14: 1188743, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37323910

RESUMO

The aim of this study was to provide a comparative analysis of chitosan (CH), copper oxide (CuO), and chitosan-based copper oxide (CH-CuO) nanoparticles for their application in the healthcare sector. The nanoparticles were synthesized by a green approach using the extract of Trianthema portulacastrum. The synthesized nanoparticles were characterized using different techniques, such as the synthesis of the particles, which was confirmed by UV-visible spectrometry that showed absorbance at 300 nm, 255 nm, and 275 nm for the CH, CuO, and CH-CuO nanoparticles, respectively. The spherical morphology of the nanoparticles and the presence of active functional groups was validated by SEM, TEM, and FTIR analysis. The crystalline nature of the particles was verified by XRD spectrum, and the average crystallite sizes of 33.54 nm, 20.13 nm, and 24.14 nm were obtained, respectively. The characterized nanoparticles were evaluated for their in vitro antibacterial and antibiofilm potential against Acinetobacter baumannii isolates, where potent activities were exhibited by the nanoparticles. The bioassay for antioxidant activity also confirmed DPPH scavenging activity for all the nanoparticles. This study also evaluated anticancer activities of the CH, CuO, and CH-CuO nanoparticles against HepG2 cell lines, where maximum inhibitions of 54, 75, and 84% were recorded, respectively. The anticancer activity was also confirmed by phase contrast microscopy, where the treated cells exhibited deformed morphologies. This study demonstrates the potential of the CH-CuO nanoparticle as an effective antibacterial agent, having with its antibiofilm activity, and in cancer treatment.

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