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1.
J Enzyme Inhib Med Chem ; 34(1): 1388-1399, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31392901

RESUMO

Fourteen novel dipeptide carboxamide derivatives bearing benzensulphonamoyl propanamide were synthesized and characterized using 1H NMR, 13C NMR, FTIR and MS spectroscopic techniques. In vivo antimalarial and in vitro antimicrobial studies were carried out on these synthesized compounds. Molecular docking, haematological analysis, liver and kidney function tests were also evaluated to assess the effect of the compounds on the organs. At 200 mg/kg body weight, 7i inhibited the multiplication of the parasite by 81.38% on day 12 of post-treatment exposure. This was comparable to the 82.34% reduction with artemisinin. The minimum inhibitory concentration (MIC) in µM ranged from 0.03 to 2.34 with 7h having MIC of 0.03 µM against Plasmodium falciparium. The in vitro antibacterial activity of the compounds against some clinically isolated bacteria strains showed varied activities with some of the new compounds showing better activities against the bacteria and the fungi more than the reference drug ciprofloxacin and fluconazole.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antimaláricos/química , Antimaláricos/farmacologia , Dipeptídeos/química , Dipeptídeos/farmacologia , Sulfonamidas/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Antimaláricos/síntese química , Bactérias/efeitos dos fármacos , Dipeptídeos/síntese química , Fungos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Testes de Sensibilidade Parasitária , Plasmodium falciparum/efeitos dos fármacos , Ratos , Sulfonamidas/química
3.
Epidemiol Mikrobiol Imunol ; 68(2): 65-70, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31398978

RESUMO

BACKGROUNDS: Snails (Gastropoda) have a mechanism for the production of a significant amount of slime and substances contained therein they use to protect themselves against bacterial or fungal pathogens. These active substances are involved in both humoral and cellular immune responses of the gastropods. The antibacterial or antifungal effect of the humoral immune component of slime lies in cytotoxic and haemagglutination activity against potential microbial pathogens. The activity of antibacterial agents present in Achatina reticulata slime against bacterial strains of Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa was tested. MATERIAL AND METHODS: A total of five samples of slime from laboratory reared Achatina reticulata were tested. To eliminate potential microbial contamination, slime samples were sterilized by UV radiation. To screen slime samples for antibacterial activity, the simple diffusion method on Mueller-Hinton agar was used. Samples diluted in guaiacol glycerol ether were used in the testing. RESULTS: The results show that the biologically active substances present in Achatina reticulata slime have an antimicrobial activity which is almost commensurate with that of the conventional antibiotics used to treat bacterial infections. The results of the determination of the antimicrobial effects of Achatina reticulata slime also highlighted viridation (partial hemolysis of erythrocytes after 24 hours of slime cultivation exposed to UV light for 60 minutes on Columbia blood agar. CONCLUSIONS: The results of the antimicrobial activity testing of selected Achatina reticulata slime samples show that the gastropod slime contains biologically active substances with a relatively significant antimicrobial activity.


Assuntos
Anti-Infecciosos , Bactérias , Gastrópodes , Animais , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Gastrópodes/microbiologia , Testes de Sensibilidade Microbiana , Muco/microbiologia
4.
Epidemiol Mikrobiol Imunol ; 68(2): 99-102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31398983

RESUMO

The increasing incidence of multiresistant bacterial strains is currently a serious health concern. These pathogens are often the cause of nosocomial infections with limited treatment options and high fatality rates. A case report is presented of an uncommon detection of four different species (Citrobacter freundii, Klebsiella pneumoniae, Escherichia coli, and Morganella morganii) producing the same type of carbapenemase, KPC-2, in a female patient during her complicated long-term hospital stay. Resistance was probably spread to other species by horizontal transmission of plasmids carrying the blaKPC-2 genes. The implementation of strict anti-epidemic measures prevented further spread of these carbapenem-resistant bacteria.


Assuntos
Antibacterianos , Bactérias , Infecções Bacterianas , Infecção Hospitalar , beta-Lactamases , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/enzimologia , Infecções Bacterianas/microbiologia , Proteínas de Bactérias/genética , Coinfecção/microbiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Feminino , Transferência Genética Horizontal , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , beta-Lactamases/genética
5.
J Agric Food Chem ; 67(33): 9382-9389, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31361959

RESUMO

Early stage exposure of foodborne substances, such as brightening agent titanium dioxide nanoparticles (TiO2 NPs), can cause long-term effects in adulthood. We aimed to explore the potential adverse effect of long-term dietary intake of TiO2 NPs. After feeding for 2-3 months from weaning, TiO2 NPs-exposed mice showed lower body weight and induced intestinal inflammation. However, this phenomenon was not observed in gut microbiota-removed mice. TiO2 NPs exposure rarely affected the diversity of microbial communities, but significantly decreased the abundance of several probiotic taxa including Bifidobacterium and Lactobacillus. Additionally, TiO2 NPs aggravated DSS-induced chronic colitis and immune response in vivo, and reduced the population of CD4+T cells, regulatory T cells, and macrophages in mesenteric lymph nodes. Therefore, dietary TiO2 NPs could interfere with the balance of immune system and dynamic of gut microbiome, which may result in low-grade intestinal inflammation and aggravated immunological response to external stimulus, thus introducing potential health risk.


Assuntos
Intestinos/efeitos dos fármacos , Intestinos/imunologia , Nanopartículas/metabolismo , Nanopartículas/toxicidade , Titânio/metabolismo , Titânio/toxicidade , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Peso Corporal/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Fatores de Tempo
6.
Pan Afr Med J ; 32: 166, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303935

RESUMO

Introduction: Superbugs are pathogenic micro-organism and especially a bacterium that has developed resistance to the medications normally used against it. As the superbug family increases, the need for appropriate diagnostic, treatment, prevention and control strategies cannot be over emphasized. Therefore, this work determined the distribution of superbug bacteria among patients on prolonged hospital admissions in three tertiary hospitals of Kano state, Nigeria. Methods: A descriptive cross sectional study was undertaken among 401 patients from medical, surgery, orthopedic and burn centre wards in a three tertiary hospitals in Kano state. A sample collected comprises wound/pus, urine, urine catheter and nasal intubation and were analysed using standard microbiological methods for Acinetobacter spp and other related nosocomial bacterial pathogens. Antibiotic susceptibility testing was done using Kirby-Bauer disc diffusion method. Results: One hundred and thirty eight (138) isolates were recovered, from the studied participants. More than 80% of the nosocomial infections (NIs) were caused by Gram-negative bacteria, predominantly Escherichia coli, Klebseilla spp, Proteus spp, Pseudomona spp and Acinetobacter spp. In-vitro antibiotic susceptibility test revealed that acinetobacter were 100% resistant to amoxicillin, co-trimoxazole, perfloxacin and imipenem. Conclusion: Superbugs (Acinetobacter species) significantly contributed to delayed hospital admissions through observed 100% resistance to used antibiotics. The healthcare managers of these hospitals and the ministry of health need to take measures against this resistant bacteria (Acinetobacter spp) especially on prescribing antibiotics that showed 100% resistant from these studied hospitals.


Assuntos
Antibacterianos/farmacologia , Infecções Bacterianas/epidemiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Idoso , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Estudos Transversais , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana Múltipla , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Centros de Atenção Terciária , Fatores de Tempo , Adulto Jovem
7.
J Agric Food Chem ; 67(30): 8303-8311, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31298535

RESUMO

Exposure to chiral pesticides poses many potential health risks. In this study, we examined the impacts of exposure to penconazole and its enantiomers on gut microbiota and metabolic profiles in mice. The relative abundance of microbiota in cecal content significantly changed following exposure to penconazole and its enantiomers. At the genus level, the relative abundances of seven gut microflora were altered following exposure to (-)-penconazole. Both (±)-penconazole and (+)-penconazole caused significant changes in the relative abundances of five gut microflora. In addition, targeted serum metabolomics analysis showed disturbed metabolic profiles following exposure. Respectively, (±)-penconazole, (+)-penconazole, and (-)-penconazole exposure significantly altered the relative levels of 29, 23, and 36 metabolites. In general, exposure to penconazole and its enantiomers caused disorders in gut microbiota and metabolic profiles of mice. The potential health risks of penconazole and its enantiomers now require further evaluation.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos/metabolismo , Praguicidas/química , Praguicidas/farmacologia , Triazóis/química , Triazóis/farmacologia , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Trato Gastrointestinal/microbiologia , Masculino , Camundongos Endogâmicos ICR , Filogenia , Estereoisomerismo
8.
J Agric Food Chem ; 67(28): 7886-7897, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31283218

RESUMO

Hard, medium, and soft wheat proteins, based on gluten content, were studied for their important roles in nanometallic surface chemistry. In situ synthesis of Au nanoparticles (NPs) was followed to determine the surface adsorption behavior of wheat protein based on the gluten contents. A greater amount of gluten contents facilitated the nucleation to produce Au NPs. X-ray photoelectron spectroscopy (XPS) surface analysis clearly showed the surface adsorption of protein on nanometallic surfaces which was almost equally prevalent for the hard, medium, and soft wheat proteins. Wheat protein conjugated NPs were highly susceptible to phase transfer from aqueous to organic phase that was entirely related to the amount of gluten contents. The presence of higher gluten content in hard wheat protein readily enabled the hard wheat protein conjugated NPs to move across the aqueous-organic interface followed by medium and soft wheat protein conjugated NPs. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS page) analysis allowed us to determine molar masses of nanometallic surface adsorbed protein fractions. Only two protein fractions of high molar masses (74 and 85 kDa) from SDS solubilized hard, medium, and soft wheat proteins preferred to adsorb on nanometallic surfaces out of more than 15 protein fractions of pure wheat protein. This made the surface adsorption of wheat protein highly selective and closely related to gluten content. Cetyltrimethylammonium bromide (CTAB) solubilized wheat protein conjugated NPs demonstrated their strong antimicrobial activities against both Gram negative and Gram positive bacteria making them suitable for their applications in food industry.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Glutens/química , Ouro/química , Nanopartículas Metálicas/química , Triticum/química , Adsorção , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Dureza
9.
J Agric Food Chem ; 67(32): 8847-8854, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31328515

RESUMO

Microbiome has been revealed as a key element involved in maintaining the circadian rhythms. Oolong tea polyphenols (OTP) has been shown to have potential prebiotic activity. Therefore, this study focused on the regulation mechanisms of OTP on host circadian rhythms. After 8 weeks of OTP administration, a large expansion in the relative abundance of Bacteroidetes with a decrease in Firmicutes was observed, which reflected the positive modulatory effect of OTP on gut flora. In addition, Kyoto Encyclopedia of Genes and Genomes pathways of ATP-binding cassette transporters, two-component system, and the biosynthesis of amino acids enriched the most differentially expressed genes after OTP treatment. Of the differentially expressed proteins identified, most were related to metabolism, genetic information processing, and environmental information processing. It underscores the ability of OTP to regulate circadian rhythm by enhancing beneficial intestinal microbiota and affecting metabolic pathways, contributing to the improvement of host microecology.


Assuntos
Camellia sinensis/química , Transtornos Cronobiológicos/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Transtornos Cronobiológicos/microbiologia , Transtornos Cronobiológicos/fisiopatologia , Modelos Animais de Doenças , Feminino , Humanos , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Chá/química
10.
Naturwissenschaften ; 106(7-8): 37, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31209578

RESUMO

Millipedes use an array of chemical compounds to defend themselves from predator attack. These chemical substances can have additional roles, i.e. defence against various pathogens. We evaluated the efficacy of the defensive secretion of Apfelbeckia insculpta (L. Koch, 1867) against bacteria, yeasts, and filamentous fungi. The tested secretion consisted of two compounds, p-cresol and phenol, and showed antibacterial, antibiofilm, and antifungal potential against all selected microorganisms. The most sensitive bacterium in our study was Pseudomonas aeruginosa, while the tested defensive secretion manifested the lowest activity against Escherichia coli. The defensive secretion of A. insculpta also showed an ability, albeit mild, to suppress biofilm formation by P. aeruginosa. Among the tested yeasts, Candida albicans and C. krusei were the most susceptible and most resistant species, respectively. Finally, the concentration of extracts obtained from the tested defensive secretion needed to achieve an antifungal effect was lowest in the case of Cladosporium cladosporioides. Fusarium verticillioides and Penicillium rubens were the micromycetes most resistant to the tested secretion. Our results indicate that antibacterial activity of the defensive secretion of A. insculpta is similar to or slightly weaker than that of streptomycin, while comparison with antimycotics showed that the tested millipede secretion has stronger activity than fluconazole, but weaker activity than nystatin and ketoconazole. The present study corroborates previous findings indicating that the defensive secretions of millipedes can have different roles apart from antipredator protection and are effective against pathogenic microorganisms.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Artrópodes/química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Fenóis/química , Animais , Anti-Infecciosos/isolamento & purificação , Península Balcânica , Testes de Sensibilidade Microbiana
11.
Nat Commun ; 10(1): 2499, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31175309

RESUMO

Soil microbial communities are intricately linked to ecosystem functioning such as nutrient cycling; therefore, a predictive understanding of how these communities respond to environmental changes is of great interest. Here, we test whether phylogenetic information can predict the response of bacterial taxa to nitrogen (N) addition. We analyze the composition of soil bacterial communities in 13 field experiments across 5 continents and find that the N response of bacteria is phylogenetically conserved at each location. Remarkably, the phylogenetic pattern of N responses is similar when merging data across locations. Thus, we can identify bacterial clades - the size of which are highly variable across the bacterial tree - that respond consistently to N addition across locations. Our findings suggest that a phylogenetic approach may be useful in predicting shifts in microbial community composition in the face of other environmental changes.


Assuntos
Bactérias/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Nitrogênio/farmacologia , Filogenia , Microbiologia do Solo , Austrália , Bactérias/genética , China , Microbiota/genética , RNA Ribossômico 16S , Solo , África do Sul , Suíça , Estados Unidos
12.
Future Microbiol ; 14: 671-689, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31161792

RESUMO

Aim: To propose newer combinations of antibiotics effective against NDM-1-producing bacterial strains. Materials & methods: Antibiotics combinations were tested by checkerboard assay. NDM-1 protein/enzyme was expressed and purified to perform enzyme kinetics, circular dichroism and fluorescence spectroscopic studies. Results: Doripenem-cefoxitin combination and doripenem-tetracycline combination showed synergistic effect toward NDM-1-producing strains. The catalytic efficiency of NDM-1 enzyme was decreased drastically by 96.6% upon doripenem-cefoxitin treatment and by 35.54% after doripenem-tetracycline treatment. Conformational changes were observed in NDM-1 upon combination treatment. Conclusion: NDM-1-producing bacterial strains show resistance to multiple antibiotics but the combination of doripenem-cefoxitin and doripenem-tetracycline are effective against them. The combination of a carbapenem and cephamycin antibiotic is proposed for future treatment options against bacteria-producing NDM-1.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cefoxitina/farmacologia , Doripenem/farmacologia , Tetraciclina/farmacologia , beta-Lactamases/efeitos dos fármacos , Bactérias/enzimologia , Bactérias/metabolismo , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Sinergismo Farmacológico , Ensaios Enzimáticos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/genética , Cinética , Testes de Sensibilidade Microbiana , Inibidores da Síntese de Proteínas/farmacologia , Termodinâmica , beta-Lactamases/análise
13.
J Agric Food Chem ; 67(26): 7325-7335, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184120

RESUMO

Tea polyphenols (TP) possess the ability to regulate dyslipidemia and gut microbiota dysbiosis. However, the underlying mechanism is still elusive. The present study explored the intervention of TP on high fat diet induced metabolic disorders, gut microbiota dysbiosis in mice, and the underlying intestinal mechanism. As a result, TP significantly ameliorated hyperlipidemia, improved the expression levels of hepatic lipid metabolism genes, and modulated gut microbiota. The underlying mechanism was supposed to rely on the maintaining of intestinal redox state by TP. Intestinal redox related indicators were significantly correlated with the distribution of gut microbiota. An unidentified genus of Lachnospiraceae, Bacteroides, Alistipes, and Faecalibaculum were identified as the biomarkers for intestinal redox state. Importantly, different dosages of TP modulated intestinal redox state and gut microbiota in varied patterns, and an overdose intake attenuated the beneficial effects on gut health. Our findings offered novel insights into the mechanism of TP on intestinal homeostasis.


Assuntos
Camellia sinensis/química , Microbioma Gastrointestinal/efeitos dos fármacos , Hiperlipidemias/tratamento farmacológico , Intestinos/microbiologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Hiperlipidemias/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Chá
14.
Pol J Microbiol ; 68(2): 225-232, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31250593

RESUMO

Drug-resistant bacteria has been a threat to public life and property. We described the trends and changes in antibiotic resistance of important pathogens in a general hospital in Zhengzhou, China from 2011 to 2016, to control antimicrobial-resistant bacteria in hospital and provide support to clinicians and decision-making departments. Five dominant bacteria were enrolled based on the data from the general hospital during 6 years. The results of antimicrobial susceptibility testing were interpreted according to Clinical and Laboratory Standards Institute (CLSI). From 2011 to 2016, a total of 19,260 strains of bacteria were isolated, of which Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii accounted for 51.98%. The resistance rate of K. pneumoniae and E. coli to carbapenem was less than 15%, but resistance of K. pneumoniae to carbapenems increased with time and resistance of E. coli to meropenem increased. The rate of extended-spectrum beta-lactamase (ESBL) production among K. pneumoniae and E. coli was decreasing. For most antibiotics, the resistance rate of ESBL-positive isolates was higher than that of ESBL-negative isolates, excluding carbapenems and cefoxitin. For S. aureus, the rate of methicillin-resistant S. aureus (MRSA) was stable. Resistance of S. aureus to mostly antibiotics decreased with time. Besides polymyxin B, P. aeruginosa and A. baumannii showed high resistance to other antibiotics. For A. baumannii, the resistance rate to mostly antibiotics was increasing. The bacteria showed high levels of resistance and multiple drug resistance. Continuous surveillance and optimizing the use of antibiotics are essential.Drug-resistant bacteria has been a threat to public life and property. We described the trends and changes in antibiotic resistance of important pathogens in a general hospital in Zhengzhou, China from 2011 to 2016, to control antimicrobial-resistant bacteria in hospital and provide support to clinicians and decision-making departments. Five dominant bacteria were enrolled based on the data from the general hospital during 6 years. The results of antimicrobial susceptibility testing were interpreted according to Clinical and Laboratory Standards Institute (CLSI). From 2011 to 2016, a total of 19,260 strains of bacteria were isolated, of which Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii accounted for 51.98%. The resistance rate of K. pneumoniae and E. coli to carbapenem was less than 15%, but resistance of K. pneumoniae to carbapenems increased with time and resistance of E. coli to meropenem increased. The rate of extended-spectrum beta-lactamase (ESBL) production among K. pneumoniae and E. coli was decreasing. For most antibiotics, the resistance rate of ESBL-positive isolates was higher than that of ESBL-negative isolates, excluding carbapenems and cefoxitin. For S. aureus, the rate of methicillin-resistant S. aureus (MRSA) was stable. Resistance of S. aureus to mostly antibiotics decreased with time. Besides polymyxin B, P. aeruginosa and A. baumannii showed high resistance to other antibiotics. For A. baumannii, the resistance rate to mostly antibiotics was increasing. The bacteria showed high levels of resistance and multiple drug resistance. Continuous surveillance and optimizing the use of antibiotics are essential.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana , China , Hospitais Gerais , Humanos , Testes de Sensibilidade Microbiana
15.
Int J Nanomedicine ; 14: 3273-3282, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190793

RESUMO

Background: Biotemplates are attractive templates for the synthesis of nanometals and inorganic compound nanostructures. Methods: In this work, for the first time, iron oxide quantum dot nanoparticles (QDNPs) were prepared using albumen as a biotemplate. Next, the prepared nanoparticles were characterized using dynamic light scattering for determination and evaluation of the hydrodynamic diameter and zeta potential of the particles. Moreover, optical and scanning electron microscopes were applied to evaluate morphology. Spherically shaped iron oxide QDNPs were obtained with appropriate particle size and distribution. Fe(NO3)3.9H2O and egg whites were used as the source of the Fe element and particle size control agent in the aqueous medium, respectively. Afterward, the effect of calcination temperature parameters on the crystallinity purity and size of Fe nanocrystals were investigated. Also, products were characterized by various detection analyses such as thermogravimetry analysis/DTA, XRD, UV-vis, Fourier transform infrared (FT-IR,) transmission electron microscopy, and SEM. In order to investigate the antibacterial effect of the synthesized Fe nanobiological samples against bacterial strains, they were dissolved in dimethyl sulfoxide and diluted using distilled water. Then, different serial dilutions of 64 µg/mL, 32 µg/mL, 16 µg/mL, 8 µg/mL, 4 3BCg/mL, 2 µg/mL, 1 µg/mL, and 0.5 µg/mL of nanobiological samples were prepared and added to the Mueller-Hinton agar medium. Results: The minimum inhibitory concentration of the synthesized iron oxide quantum dot nanobiological was determined against pathogenic microbial strains of bacteria including Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens, Micrococcus luteus, Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, and Klebsiella pneumonia on the culture medium plate. Conclusion: The present nanobiological samples can be considered as a new material candidate for antibacterial drugs.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Proteínas do Ovo/química , Compostos Férricos/química , Nanopartículas/química , Pontos Quânticos/química , Animais , Difusão Dinâmica da Luz , Camundongos , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Espectrofotometria Ultravioleta , Difração de Raios X
16.
Int J Nanomedicine ; 14: 3427-3438, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190801

RESUMO

Background: Biogenic silver nanoparticles (AgNPs) have wider range of biomedical applications. The present work synthesized Tp-AgNPs using mycelial extract of endophytic fungus Talaromyces purpureogenus (MEEF), characterized, and analyzed for antibacterial, anti-proliferation and cell wounding healing activities. Methods: The synthesized Tp-AgNPs were characterized by UV-visible spectrophotometer (UV-Vis), field emission transmission electron microscopy (FETEM) with energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), particle size analysis (PSA) and X-ray diffraction (XRD). Further, antibacterial activity was determined by Kirby-Bauer test and anti-proliferation activity was tested in human lung carcinoma A549 by water-soluble tetrazolium and flow cytometer assay. In addition, cell wounding healing activity was determined by scratch assay. Results: UV-Vis results displayed a strong absorption peak from 390 nm to 420 nm, which indicated the successful synthesis of Tp-AgNPs. FETEM-EDS results indicated the round and triangle shaped Tp-AgNPs with the average size of 25 nm in accordance with PSA. FTIR analysis indicated the involvement of various functional molecules from MEEF in the synthesis of Tp-AgNPs. XRD result proved nature of Tp-AgNPs as a high-quality crystal. The Tp-AgNPs significantly inhibited the growth of bacterial pathogens at the minimal inhibitory concentration of 16.12 µg.mL-1 for Gram+, and 13.98 µg.mL-1 for Gram- bacteria. Further, Tp-AgNPs (2 µg.mL-1) showed a strong anti-proliferation effect in A549. Interestingly, Tp-AgNPs was not cytotoxic to normal NIH3T3 cells. In addition, the NPs exhibited a strong cell wounding healing activity. Conclusion: This work biosynthesized AgNPs with strong antibacterial, anticancer and cell wound healing properties using endophytic fungus T. purpureogenus.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Talaromyces/metabolismo , Células A549 , Animais , Bactérias/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Humanos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Prata/química , Cicatrização/efeitos dos fármacos
17.
BMC Complement Altern Med ; 19(1): 146, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227024

RESUMO

BACKGROUND: There is increasing interest in the pharmaceutical and food industries to substitute synthetic chemicals with naturally occurring compounds possessing bioactive properties. Plants are valuable sources of bioactive compounds. The present study investigates the chemical composition and antioxidant, antimicrobial, and anticancer activities of ethanolic extracts (EEs) and essential oils (EOs) from two species in the Lamiaceae family, Ocimum basilicum L. and Thymus algeriensis Boiss. & Reut., cultivated in the Algerian Saharan Atlas. METHODS: The total flavonoid contents of the plants' ethanolic extracts were determined by the aluminium chloride method, while the total phenols were determined using the Folin-Ciocalteu method. Essential oils were obtained by hydrodistillation of the aerial parts of the plants and were analysed by GC-MS. The free radical-scavenging ability and antioxidant potential of the plants' EEs and EOs were probed using the 2, 2-diphenyl-picrylhydrazyl radical-scavenging, ABTS radical-scavenging, ferric-reducing power and phosphomolybdenum assays. The antimicrobial activities were evaluated against several pathogens characteristic of gram-negative bacteria (three species), gram-positive bacteria (three species) and fungi (two species). The microdilution method was used to estimate the minimum inhibitory concentrations (MICs). The oils' anticancer potential against several cancer types was also studied using the MTT assay and reported as the toxic doses that resulted in a 50% reduction in cancer cell growth (LD50). RESULTS: Phenolic compounds in the EEs from both plants were analysed by HPLC and demonstrated a rich flavonoid content. Chemical analysis of the essential oil from Ocimum basilicum revealed 26 unique compounds, with linalool (52.1%) and linalyl acetate (19.1%) as the major compounds. A total of 29 compounds were identified in the essential oil from Thymus algeriensis, with α-terpinyl acetate (47.4%), neryl acetate (9.6%), and α-pinene (6.8%) as the major compounds. The ethanolic extracts and essential oils from both plants exhibited moderate antioxidant activities and moderate to weak antimicrobial activities. Furthermore, anticancer activities against the examined human cancer cell lines were associated with only the EOs from both plants, with LD50 values ranging between 300 and 1000 µg/mL. CONCLUSION: The results suggest that the bioactive compounds found in the ethanolic extracts and essential oils from Ocimum basilicum and Thymus algeriensis, with diverse antioxidant, antimicrobial and anticancer activities, may have beneficial applications in nutraceutical and pharmaceutical technologies.


Assuntos
Ocimum basilicum/química , Óleos Voláteis/química , Óleos Vegetais/química , Thymus (Planta)/química , Argélia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Linhagem Celular Tumoral , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Fenol/química , Fenol/farmacologia , Óleos Vegetais/farmacologia
18.
BMC Complement Altern Med ; 19(1): 150, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242939

RESUMO

BACKGROUND: Traditional medicine remedies are commonly used for treatment of diverse ailments including bacterial infections. The activity against resistant bacteria and safety of some remedies sold as anti-infective treatments in market places in Buea, Southwest Cameroon were investigated as potential alternative treatment to counter increasing antibiotic resistance. METHODS: Ten remedies were purchased, their components documented and microbial load estimated. Methanol extracts of the remedies were tested for antibacterial activity by disc diffusion and microdilution. Cytotoxicity was evaluated on monkey kidney epithelial cells (LLC-MK2) while acute oral toxicity was done in BALB/c mice for the bactericidal extract. Extracts were further analysed using phytochemical tests. RESULTS: All the remedies had microbial loads above the acceptable limit of 105 CFU/g. The highest activity was produced by extracts of four remedies (TP 1, 2, 4, 6a, 6b) against all clinical isolates among which three were active against four control strains. Zones of inhibition ranged from 8 to 27 mm. Two of the four extracts produced zones ≥20 mm against multidrug resistant clinical isolates of Citrobacter freundii and Escherichia coli but were less active compared to Gentamycin positive control (P < 0.0001-0.0014). The most active extracts also recorded minimum inhibitory concentrations of 1 to 4 mg/mL. One of them (TP2) was bactericidal against a clinical isolate of methicillin-resistant Staphylococcus aureus with a minimum bactericidal concentration of 8 mg/mL. Extracts of six remedies did not show cytotoxicity and no mortality or adverse effect was recorded in the acute oral toxicity test. Phytochemical screening showed the most active extracts contained relatively high amounts of alkaloids and flavonoids. CONCLUSION: Only four of the eight remedies tested showed activity against multidrug resistant bacteria suggesting some of these remedies may not be effective against bacterial infections. Production and handling methods should be improved and the product quality controlled to ensure biosecurity. The remedies which were both active and non-toxic should be further investigated including in vivo experiments to assess their efficacy.


Assuntos
Antibacterianos/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Camarões , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Feminino , Humanos , Medicina Tradicional , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/toxicidade , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Plantas Medicinais/microbiologia
19.
Ecotoxicol Environ Saf ; 181: 381-387, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31212186

RESUMO

The effects of Bt Cry9Ee toxin on honey bee, Apis mellifera L., survival, developmental rate, larval weight, pollen consumption, and midgut bacterial diversity were tested in the laboratory. Honey bee larvae and adults were reared in vitro and fed a diet that contained Cry9Ee toxin at 0.01, 0.1, 1, and 10 mg/L. Cry9Ee toxin 0.01, 0.1, and 1 mg/L in diet used in this study may represent a value closer to field relevance and the highest concentration is unlikely to be encountered in the field and thus represent a worst case scenario. The dependent variables were compared for groups of honey bees feeding on treated diet and those feeding on negative control (no addition of a test substance), solvent control (0.01 mM Na2CO3), and positive control diet (dimethoate 45 mg/L). Bt Cry9Ee toxin did not affect survival or larval weight, and the result was great confidence in accepting the null hypothesis by power analysis. The effect on development rates and pollen consumption were the inconclusive results because the post-hoc power was less than 0.8. Furthermore, the midgut bacterial structure and compositions were determined using high-throughput sequencing targeting the V3-V4 regions of the 16S rDNA. All core honey bee intestinal bacterial class such as γ-Proteobacteria, Actinobacteria, α-Proteobacteria, Bacilli, ß-Proteobacteria, and Bacteroidia were detected, and no significant changes were found in the species diversity and richness between Cry9Ee treatments and laboratory control.


Assuntos
Proteínas de Bactérias/toxicidade , Abelhas/efeitos dos fármacos , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Animais , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Abelhas/crescimento & desenvolvimento , Sistema Digestório/microbiologia , Larva/efeitos dos fármacos , Pólen
20.
Sheng Wu Gong Cheng Xue Bao ; 35(5): 847-856, 2019 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-31223003

RESUMO

Pectobacterium carotovorum subsp. carotovorum is one of the world's top ten plant pathogens, mainly infecting cruciferous economic crops and ornamental flowers. In this study, an antibacterial gene cpxP (Gene ID: 29704421) was cloned from the genome of Pectobacterium carotovorum subsp. carotovorum, and constructed on the prokaryotic expression plasmid pET-15b, and the recombinant plasmid was transformed into Escherichia coli BL21 (DE3), then stability and bacteriostatic experiments of the purified CpxP protein were performed. The final concentration of IPTG was 1 mmol/L, obtaining high-efficiency exogenous expression of the CpxP protein. There was no other protein after purification, and the destined protein exhibited good thermal stability and pH stability. The antibacterial test results showed that the inhibition rate of the CpxP protein on carrot slice was 44.89% while the inhibition rate on potato slice was 59.41%. To further explain its antibacterial mechanism, studying the spatial structure of this protein can provide new ideas for the control of soft rot and new protein pesticide targets.


Assuntos
Bactérias , Proteínas de Bactérias , Proteínas de Membrana , Pectobacterium carotovorum , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/farmacologia , Escherichia coli/genética , Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/farmacologia , Pectobacterium carotovorum/genética , Pectobacterium carotovorum/metabolismo , Plasmídeos/genética
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