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1.
Biomimetics (Basel) ; 8(6)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37887583

RESUMO

The prevalence of multidrug-resistant (MDR) bacteria has recently increased dramatically, seriously endangering human health. Herein, amoxicillin (Amoxi)-conjugated gold nanoparticles (AuNPs) were created as a novel drug delivery system to overcome MDR bacteria. MDR bacteria were isolated from a variety of infection sources. Phenotype, biotype, and 16S rRNA gene analyses were used for isolate identification. Additionally, Juniperus excelsa was used for the production of AuNPs. The conjugation of AuNPs with Amoxi using sodium tri-polyphosphate (TPP) as a linker to produce Amoxi-TPP-AuNPs was studied. The AuNP and Amoxi-TPP-AuNP diameters ranged from 15.99 to 24.71 nm, with spherical and hexagonal shapes. A total of 83% of amoxicillin was released from Amoxi-TPP-AuNPs after 12 h, and after 3 days, 90% of the medication was released. The Amoxi-TPP-AuNPs exhibited superior antibacterial effectiveness against MRSA and MDR E. coli strains. Amoxi-TPP-AuNPs had MICs of 3.6-8 µg mL-1 against the tested bacteria. This is 37.5-83 fold higher compared to values reported in the literature. Amoxi-TPP-AuNPs exhibit a remarkable ability against MRSA and E. coli strains. These results demonstrate the applicability of Amoxi-TPP-AuNPs as a drug delivery system to improve therapeutic action.

2.
Int J Biol Macromol ; 250: 126219, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37567518

RESUMO

Wound infections with rising incidences of multi-drug resistant bacteria are among the public health problems worldwide. The current study describes wound dressing materials made from biodegradable polyhydroxybutyrate (PHB) combined with AgNPs and gelatin (AgNPs/Gelatin/PHB). Microbial PHB was mixed with gelatin (1:2) to form a polymer matrix which was loaded with different concentrations of AgNPs (8.3-133 µg/mL). The statistical results of AgNPs synthesizing based on Box-Behnken design revealed that 1.247 mM silver nitrate and 24.054 % of Corchorus olitorius leaf extract concentration at pH (8.07) were the optimum values for the biosynthesis. UV-Vis spectroscopy, FTIR study and XRD reflects that nanoparticles are formed. The UV-Vis spectroscopy of Gelatin/PHB/AgNPs exhibited two specific bands at 298 nm and 371 nm, which confirm the formation of the conjugate. AgNPs had MICs and MBCs of (24.9, 24.9, and 12.45 µg/mL) and (33.25, 33.25, and 16.6 µg/mL) against (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus). The MIC and MBC of AgNPs/Gelatin/PHB against the same tested bacteria were 31.1 µg and 41.5 µg, respectively. AgNPs/Gelatin/PHB exhibit excellent antimicrobial efficacy against bacteria. Sterilized gauze loaded with 31.1 µg of AgNPs/Gelatin/PHB acted as an effective wound dressing. Thus, the study highlights the importance of wound dressings developed from degradable AgNPs/Gelatin/PHB in enhancing antimicrobial efficiency and facilitating a better wound healing process.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Probióticos , Antibacterianos/farmacologia , Antibacterianos/química , Gelatina , Nanopartículas Metálicas/química , Bactérias , Bandagens , Testes de Sensibilidade Microbiana
3.
J Microbiol Biotechnol ; 32(12): 1537-1546, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36379700

RESUMO

Staphylococcus aureus is a cause of high mortality in humans and therefore it is necessary to prevent its transmission and reduce infections. Our goals in this research were to investigate the frequency of methicillin-resistant S. aureus (MRSA) in Taif, Saudi Arabia, and assess the relationship between the phenotypic antimicrobial sensitivity patterns and the genes responsible for resistance. In addition, we examined the antimicrobial efficiency and application of silver nanoparticles (AgNPs) against MRSA isolates. Seventy-two nasal swabs were taken from patients; MRSA was cultivated on Mannitol Salt Agar supplemented with methicillin, and 16S rRNA sequencing was conducted in addition to morphological and biochemical identification. Specific resistance genes such as ermAC, aacA-aphD, tetKM, vatABC and mecA were PCR-amplified and resistance plasmids were also investigated. The MRSA incidence was ~49 % among the 72 S. aureus isolates and all MRSA strains were resistant to oxacillin, penicillin, and cefoxitin. However, vancomycin, linezolid, teicoplanin, mupirocin, and rifampicin were effective against 100% of MRSA strains. About 61% of MRSA strains exhibited multidrug resistance and were resistant to 3-12 antimicrobial medications (MDR). Methicillin resistance gene mecA was presented in all MDR-MRSA strains. Most MDR-MRSA contained a plasmid of > 10 kb. To overcome bacterial resistance, AgNPs were applied and displayed high antimicrobial activity and synergistic effect with penicillin. Our findings may help establish programs to control bacterial spread in communities as AgNPs appeared to exert a synergistic effect with penicillin to control bacterial resistance.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Resistência a Meticilina , Antibacterianos/farmacologia , Staphylococcus aureus , Prata/farmacologia , Prevalência , RNA Ribossômico 16S , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Proteínas de Ligação às Penicilinas/genética , Testes de Sensibilidade Microbiana , Meticilina/farmacologia , Infecções Estafilocócicas/microbiologia
4.
BMC Microbiol ; 22(1): 183, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869433

RESUMO

BACKGROUND: Polyhydroxybutyrate (PHB) is a biopolymer formed by some microbes in response to excess carbon sources or essential nutrient depletion. PHBs are entirely biodegradable into CO2 and H2O under aerobic and anaerobic conditions. It has several applications in various fields such as medicine, pharmacy, agriculture, and food packaging due to its biocompatibility and nontoxicity nature. RESULT: In the present study, PHB-producing bacterium was isolated from the Dirout channel at Assiut Governorate. This isolate was characterized phenotypically and genetically as Bacillus cereus SH-02 (OM992297). According to one-way ANOVA test, the maximum PHB content was observed after 72 h of incubation at 35 °C using glucose and peptone as carbon and nitrogen source. Response surface methodology (RSM) was used to study the interactive effects of glucose concentration, peptone concentration, and pH on PHB production. This result proved that all variables have a significant effect on PHB production either independently or in the interaction with each other. The optimized medium conditions with the constraint to maximize PHB content and concentration were 22.315 g/L glucose, and 15.625 g/L peptone at pH 7.048. The maximum PHB content and concentration were 3100.799 mg/L and 28.799% which was close to the actual value (3051 mg/l and 28.7%). The polymer was identified as PHB using FTIR, NMR, and mass spectrometry. FT-IR analysis showed a strong band at 1724 cm- 1 which attributed to the ester group's carbonyl while NMR analysis has different peaks at 169.15, 67.6, 40.77, and 19.75 ppm that were corresponding to carbonyl, methine, methylene, and methyl resonance. Mass spectroscopy exhibited molecular weight for methyl 3- hydroxybutyric acid. CONCLUSION: PHB-producing strain was identified as Bacillus cereus SH-02 (OM992297). Under optimum conditions from RSM analysis, the maximum PHB content and concentration of this strain can reach (3100.799 mg/L and 28.799%); respectively. FTIR, NMR, and Mass spectrometry were used to confirm the polymer as PHB. Our results demonstrated that optimization using RSM is one of the strategies used for reducing the production cost. RSM can determine the optimal factors to produce the polymer in a better way and in a larger quantity without consuming time.


Assuntos
Bacillus cereus , Butiratos/metabolismo , Peptonas , Bacillus cereus/genética , Carbono , Glucose , Hidroxibutiratos , Poliésteres , Polímeros , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Antibiotics (Basel) ; 11(6)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35740163

RESUMO

Caries lesions during cement repairs are a severe issue, and developing a unique antimicrobial restorative biomaterial can help to reduce necrotic lesion recurrence. As a result, Thymus vulgaris extract was used to biosynthesize copper nanoparticles (TVE-CuNPs) exhibiting different characteristics (TVE). Along with TVE-CuNPs, commercial silver nanoparticles (AgNPs) and metronidazole were combined with glass ionomer cement (GIC) to test its antibacterial efficacy and compressive strength. FTIR, XRD, UV-Vis spectrophotometry, and TEM were applied to characterize the TVE-CuNPs. Additionally, AgNPs and TVE-CuNPs were also combined with metronidazole and GIC. The modified GIC samples were divided into six groups, where groups 1 and 2 included conventional GIC and GIC with 1.5% metromidazole, respectively; group 3 had GIC with 0.5% TVE-CuNPs, while group 4 had 0.5% TVE-CuNPs with metronidazole in 1.5%; group 5 had GIC with 0.5% AgNPs, and group 6 had 0.5% AgNPs with metronidazole at 1.5%. An antimicrobial test was performed against Staphylococcus aureus (S. aureus) and Streptococcus mutans (S. mutans) by the disc diffusion method and the modified direct contact test (MDCT). GIC groups 4 and 6 demonstrated a greater antimicrobial efficiency against the two tested strains than the other groups. In GIC groups 4 and 6, the combination of GIC with two antimicrobial agents, 1.5% metronidazole and 0.5% TVE-CuNPs or AgNPs, enhanced the antimicrobial efficiency when compared to that of the other groups with or without a single agent. GIC group specimens combined with nanosilver and nanocopper had similar mean compressive strengths when compared to the other GIC groups. Finally, the better antimicrobial efficacy of GIC boosted by metronidazole and the tested nanoparticles against the tested strains may be relevant for the future creation of more efficient and modified restorations to reduce dental caries lesions.

6.
Molecules ; 27(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35056835

RESUMO

In the present study, Zingiber officinale is used for the synthesis of Zingiber officinale capped silver nanoparticles (ZOE-AgNPs) and compares the antimicrobial efficacy and compressive strength of conventional glass ionomer cement (GIC) combined with ZOE-AgNPs, lyophilized miswak, and chlorhexidine diacetate (CHX) against oral microbes. Five groups of the disc-shaped GIC specimens were prepared. Group A: lyophilized miswak and GIC combination, Group B: ZOE-AgNPs and GIC combinations, Group C: CHX and GIC combination, Group D: ZOE-AgNPs + CHX + GIC; Group E: Conventional GIC. Results confirmed the successful formation of ZOE-AgNPs that was monitored by UV-Vis sharp absorption spectra at 415 nm. The X-ray diffractometer (XRD) and transmission electron microscope (TEM) results revealed the formation of ZOE-AgNPs with a mean size 10.5-14.12 nm. The peaks of the Fourier transform infrared spectroscopy (FTIR) were appearing the involvement of ZOE components onto the surface of ZOE-AgNPs which played as bioreducing, and stabilizing agents. At a 24-h, one-week and three-week intervals, Group D showed the significantly highest mean inhibitory zones compared to Group A, Group B, and Group C. At microbe-level comparison, Streptococcus mutans and Staphylococcus aureus were inhibited significantly by all the specimens tested except group E when compared to Candida albicans. Group D specimens showed slightly higher (45.8 ± 5.4) mean compressive strength in comparison with other groups. The combination of GIC with ZOE-AgNPs and chlorhexidine together enhanced its antimicrobial efficacy and compressive strength compared to GIC with ZOE-AgNPs or lyophilized miswak or chlorhexidine combination alone. The present study revealed that The combination of GIC with active components of ZOE-AgNPs and chlorhexidine paves the way to lead its effective nano-dental materials applications.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Clorexidina/farmacologia , Cimentos de Ionômeros de Vidro/farmacologia , Nanopartículas Metálicas/administração & dosagem , Salvadoraceae/química , Prata/química , Antibacterianos/química , Zingiber officinale/química , Teste de Materiais , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia
7.
Molecules ; 26(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34833924

RESUMO

Dental caries results from the bacterial pathogen Streptococcus mutans (S. mutans) and is the maximum critical reason for caries formation. Consequently, the present study aims to evaluate the antibacterial activity of a newly synthesized nanoantibiotic-Biodentine formulation. The silver nanoparticles (ROE-AgNPs) were biosynthesized from the usage of Rosmarinus officinalis L. extract (ROE) and conjugated with cefuroxime to form Cefuroxime-ROE-AgNPs. Using Biodentine™ (BIOD), five groups of dental materials were prepared, in which Group A included conventional BIOD, Group B included BIOD with ROE-AgNPs, Groups C and D included BIOD with Cefuroxime-ROE-AgNPs at concentrations of 0.5% and 1.5% cefuroxime, respectively, and Group E included BIOD with 1.5% cefuroxime. The synthesized ROE-AgNPs or Cefuroxime-ROE-AgNPs were characterized for conjugating efficiency, morphology, particle size, and in vitro release. Minimum inhibitory concentration (MIC) of the cefuroxime, ROE-AgNPs, and Cefuroxime-ROE-AgNPs were additionally evaluated against cefuroxime resistant S. mutans, which furthered antibacterial efficacy of the five groups of dental materials. The UV-Visible spectrum showed the ROE-AgNPs or Cefuroxime-ROE-AgNPs peaks and their formation displayed through transmission electron microscopy (TEM), X-ray diffraction (XRD) pattern, and Fourier transforms infrared (FTIR) analysis. The end result of Cefuroxime-ROE-AgNPs showed conjugating efficiency up to 79%. Cefuroxime-ROE-AgNPs displayed the highest antibacterial efficacy against S. mutans as compared to cefuroxime or ROE-AgNPs alone. Moreover, the MIC of ROE-AgNPs and Cefuroxime-ROE-AgNPs was detected against S. mutans to be 25 and 8.5 µg/mL, respectively. Consequently, Cefuroxime-ROE-AgNPs displayed that a decrease in the MIC reached to more than three-fold less than MIC of ROE-AgNPs on the tested strain. Moreover, Cefuroxime-ROE-AgNPs/BIOD was employed as a novel dental material that showed maximum antimicrobial activity. Groups C and D of novel materials showed inhibitory zones of 19 and 26 mm, respectively, against S. mutans and showed high antimicrobial rates of 85.78% and 91.17%, respectively. These data reinforce the utility of conjugating cefuroxime with ROE-AgNPs to retrieve its efficiency against resistant S. mutant. Moreover, the nanoantibiotic delivered an advantageous antibacterial effect to BIOD, and this may open the door for future conjugation therapy of dental materials against bacteria that cause dental caries.


Assuntos
Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Cefuroxima/química , Cefuroxima/farmacologia , Nanopartículas Metálicas/química , Silicatos/química , Silicatos/farmacologia , Prata/química , Streptococcus mutans/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Cárie Dentária/tratamento farmacológico , Testes de Sensibilidade Microbiana/métodos , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/farmacologia
8.
Microorganisms ; 9(11)2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34835520

RESUMO

Polyhydroxybutyrates (PHBs) are macromolecules synthesized by bacteria. Because of their fast degradability under natural environmental conditions, PHBs were selected as alternatives for the production of biodegradable plastics. Sixteen PHB-accumulating strains were selected and compared for their ability to accumulate PHB granules inside their cells. Isolate AS-02 was isolated from cattle manure and identified as Bacillus wiedmannii AS-02 OK576278 by means of 16S rRNA analysis. It was found to be the best producer. The optimum pH, temperature, and incubation period for the best PHB production by the isolate were 7, 35 °C, and 72 h respectively. PHB production was the best with peptone and glucose as nitrogen and carbon sources at a C/N ratio of (2:1). The strain was able to accumulate 423, 390, 249, 158, and 144 mg/L PHB when pretreated orange, mango, banana, onion peels, and rice straw were used as carbon sources, respectively. The extracted polymer was characterized by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and GC-MS spectroscopy, which confirmed the structure of the polymer as PHB. The isolate B. wiedmannii AS-02 OK576278 can be considered an excellent candidate for industrial production of PHB from agricultural wastes.

9.
3 Biotech ; 11(6): 255, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33987072

RESUMO

We report here the synthesis of silver nanoparticles (AgNPs) from an aqueous extract of Juniperus excelsa and their use as an antimicrobial agent on their own or in combination with antibiotics in inhibiting multidrug-resistant bacteria (MDR). One strategy of bacterial infection control in wound healing is AgNP biosynthesis. We collected bacterial strains of patient skin infections from Al-Adwani Hospital. Phenotyping, biotyping, and molecular characterizations were applied using 16S rRNA gene analysis of bacterial isolates. Our results identified tested MDR bacteria Staphylococcus aureus strains (methicillin-resistant and methicillin-susceptible) and Proteus mirabilis. Gas chromatography/mass spectrometry (GC/MS) analysis was used to identify the Juniperus excelsa biomolecules in the leaf extract acting as both reducing and capping agents in the biosynthesis of AgNPs. The AgNPs appeared hexagonal and spherical in shape upon transmission electron microscope (TEM) analysis. The AgNP sizes ranged from 16.08 to 24.42 nm. X-ray diffraction (XRD) analysis confirmed the crystalline nature of the particles. The minimum inhibitory concentrations (MICs) of the AgNPs against the tested MDR bacteria ranged from 48 to 56 µg/ml, while the minimum bactericidal concentrations (MBCs) of the AgNPs against the tested strains ranged from 72 to 96 µg/ml. The AgNPs showed a good synergistic efficacy with Cefaclor, Cefoxitin, and Erythromycin. Their efficiency showed a threefold increase in the inhibition of tested strains when used in wound dressing, due to the AgNPs potentially activating the antibiotics. Consequently, we can use AgNPs with Cefaclor, Cefoxitin, and Erythromycin antibiotics as alternative antimicrobial agents, and they could be utilized in wound dressing to prevent microbial infections.

10.
Nanotechnology ; 32(21)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33657016

RESUMO

Background. The development of dental caries is associated with various microorganisms and secondary caries formation is the main cause of restorations failure. The advice for restorative dental materials that have antimicrobial properties has stimulated the introduction of materials containing different antibacterial agents.Objectives. The present study has been designed to synthesize silver nanoparticles (AgNPs) and incorporate AgNPs and amoxicillin into glass ionomer cement (GIC) to synergize its effect on oral microbes. The effect of the added antimicrobial agents on compressive strength (CS) of GIC was also evaluated.Material and methods. Biosynthesis of AgNPs was done usingCupressus macrocarpaextract and AgNPs were characterized. A total of 120 disc-shaped specimens were prepared and classified into 4 main groups where Group A includes conventional GIC, Groups B and C include GIC with AgNPs or amoxicillin, respectively, while Group D included GIC with both AgNPs and amoxicillin. Each group was tested for the antimicrobial activity against bothStreptococcus mutans(S. mutans) andStaphylococcus aureus(S. aureus). The distribution of biofilm was examined via a scanning electron microscope. The CS of the tested material was measured using a Material Test System.Results. The UV-visible spectrum showed a peak of 429 nm. Transmission electron microscopy, x-ray diffraction pattern and Fourier transform infrared analysis confirmed the formation of AgNPs with spherical to oblong polydispersed particles of diameter in the range of 13.5-25.8 nm. The maximum inhibitory zone was recorded for group D against both tested bacteria with a mean of 29 mm at first 24 h period to 15 mm at three weeks and showed antimicrobial rate 92.2% and 92.56%, against both strains, respectively. Additionally, group D disintegrated the structure ofS. aureusbiofilm and even kill bacteria in the biofilms. The addition of AgNPs and amoxicillin caused an insignificant effect on CS of GIC.Conclusion.TheAgNPs showed a synergistic effect in combination with amoxicillin and GIC dental restorative material against studied microorganisms. The agents can be safely added with minimal effect on the mechanical properties of the original cement.


Assuntos
Amoxicilina/farmacologia , Anti-Infecciosos/química , Cimentos de Ionômeros de Vidro/química , Nanopartículas Metálicas/química , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Cupressus/química , Cupressus/metabolismo , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
11.
Curr Microbiol ; 77(8): 1767-1779, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32328748

RESUMO

In case of Escherichia coli and Klebsiella pneumoniae infection, the increased prominence of multidrug-resistance strains has become the greatest challenge in the urinary tract disease treatment. Therefore, the 16S rRNA sequencing of multidrug-resistant strains was performed, in addition to those of plasmids and genes responsible for multidrug resistance. These strains showed containing responsible genes Sulfonamides sul1, Tetracycline Tet(A), Tetracycline Tet(B), chloramphenicol catA1, ß-lactams blaSHV, and cmlA. Also, the strains demonstrated resistance to at least 10 types of antibiotics or more due to carrying various plasmids. For increasing the level of public health in daily life and treatment of multidrug-resistant bacteria, the nanomedicine was employed. Consequently, ZnO nanoparticles (ZnONPs-E) were synthesized by employing supernatant of Escherichia hermannii strain isolated from raw milk source. The E. hermannii strain produces high concentration of ZnONPs-E compared to other strains so we used it in this study. This ZnONPs-E has a minimal inhibitory concentration (MIC) ranged from the concentration 10 µg/ml to 40 µg/ml against E. coli and K. pneumoniae, respectively. The antimicrobial efficiency of ZnONPs-E was 40 µg/ml and it was superior to the reported values in literature. Moreover, SEM results evident for distorted membrane morphology, blebbing of membrane, cell elongation, and leakage of cellular contents due to ZnONPs-E activity against tested bacteria. These results indicated that the ZnONPs-E exhibited interesting antimicrobial activity against pathogenic extended-spectrum ß-lactamases (ESBLs) strains. The present study revealed that the active components entered in biosynthesis of ZnONPs-E pave the way to lead its effective nano-medical and drug delivery applications.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Nanopartículas/química , Óxido de Zinco/farmacologia , Bactérias/classificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Genoma Bacteriano , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , RNA Ribossômico 16S/genética
12.
Int J Nanomedicine ; 15: 1889-1901, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256066

RESUMO

OBJECTIVES: Due to the expanded bacterial genetic tolerance to antibiotics through different mechanisms, infectious diseases of MDR bacteria are difficult for treatment. Consequently, we synthesized drug conjugated nanoparticles to dissolve this problem. Moreover, the present study aims to display the cell death status treated with cefotaxime-CS-AgNPs and also, apoptosis pathways of human RPE-1 normal cells and human MCF-7 breast cancer cells. METHODS: Here, we demonstrate the possibility to synthesize AgNPs and conjugate them with cefotaxime to survey the probability of cefotaxime-CS-AgNPs as an antimicrobial agent against cefotaxime-resistant strains E. coli and MRSA. RESULTS: TEM showed the size of AgNPs, CS-AgNPs and cefotaxime-CS-AgNPs ranged from 7.42 to 18.3 nm, 8.05-23.89 nm and 8.48-25.3 nm, respectively, with a spherical shape. The cefotaxime-CS-AgNPs enhanced the high antimicrobial properties compared to AgNPs or pure antibiotic. The MIC of Cefotaxime-CS-AgNPs ranged from 3 µg/mL to 8 µg/mL against tested E. coli and MRSA bacteria. Consequently, the highest reduction in the MIC of cefotaxime-CS-AgNPs was noted against tested strains ranging from 22% to 96%. Comparing cefotaime-CS-AgNPs to AgNPs we showed that cefotaime-CS-AgNPs have no cytotoxic effect on normal cells at even 12 µg/mL for 24 hrs. The IC50 for the AgNPs and cefotaxime-CS-AgNPs was 12 µg/mL for human RPE-1 normal cells and human MCF-7 breast cancer cell lines. The pro-apoptotic genes p53, p21, and Bax of cancer cell lines significantly upregulated followed by downregulated by anti-apoptotic gene Bcl-2 after 48 hrs at 24 µg/mL, and this concentration represents the most effective dose. CONCLUSION: Results enhanced the conjugating utility in old unresponsive cefotaxime to AgNPs to restore its efficiency against previous strains and demonstrated potential therapeutic applications of cefotaxime-CS-AgNPs. Moreover, this research gives remarkable insights for designing nanoscale delivery and curative systems that have a pronounced cytotoxic activity on cancer cells and are safe to normal cells.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Cefotaxima/química , Cefotaxima/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Prata/química , Prata/farmacologia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
13.
J Microbiol Biotechnol ; 28(9): 1563-1572, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30369118

RESUMO

Gold nanoparticles (AuNP) and their conjugates have been gaining a great deal of recognition in the medical field. Meanwhile, extended-spectrum ß-lactamases (ESBL)-producing bacteria are also demonstrating a challenging problem for health care. The aim of this study was the biosynthesis of AuNP using Rosa damascenes petal extract and conjugation of ceftriaxone antibiotic (Cef-AuNP) in inhibiting ESBL-producing bacteria and study of in vitro anticancer activity. Characterization of the synthesized AuNP and Cef-AuNP was studied. ESB-Lproducing strains, Acinetobacter baumannii ACI1 and Pseudomonas aeruginosa PSE4 were used for testing the efficacy of Cef-AuNP. The cells of MCF-7 breast cancer were treated with previous AuNP and Cef-AuNP at different time intervals. Cytotoxicity effects of apoptosis and its molecular mechanism were evaluated. Ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy established the formation of AuNP and Cef-AuNP. Transmission electron microscope demonstrated that the formed nanoparticles were of different shapes with sizes of 15~35 nm and conjugation was established by a slight increase in size. Minimum inhibitory concentration (MIC) values of Cef-AuNP against tested strains were obtained as 3.6 and 4 µg/ml, respectively. Cef-AuNP demonstrated a decrease in the MIC of ceftriaxone down to more than 27 folds on the studied strains. The biosynthesized AuNP displayed apoptotic and time-dependent cytotoxic effects in the cells of MCF-7 at a concentration of 0.1 µg/ml medium. The Cef-AuNP have low significant effects on MCF-7 cells. These results enhance the conjugating utility in old unresponsive ceftriaxone with AuNP to restore its efficiency against otherwise resistant bacterial pathogens. Additionally, AuNP may be used as an alternative chemotherapeutic treatment of MCF-7 cancer cells.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Ceftriaxona , Ouro/química , Nanopartículas Metálicas/química , Extratos Vegetais , Apoptose/efeitos dos fármacos , Apoptose/genética , Bactérias/efeitos dos fármacos , Bactérias/enzimologia , Ceftriaxona/química , Ceftriaxona/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células MCF-7 , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rosa/química , beta-Lactamases/metabolismo
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