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1.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257327

RESUMO

Due to the versatile bioreactivity of aroyldihydrazone complexes as cost-effective alternatives with different transition metals, two novel bimetallic homo-complexes (VOLph and CuLph) were prepared via the coordination of a terephthalic dihydrazone diisatin ligand (H2Lph) with VO2+ and Cu2+ ions, respectively. The structure elucidation was confirmed by alternative spectral methods. Biologically, the H2Lph ligand and its MLph complexes (M2+ = VO2+ or Cu2+) were investigated as antimicrobial and anticancer agents. Their biochemical activities towards ctDNA (calf thymus DNA) were estimated using measurable titration viscometrically and spectrophotometrically, as well as the gel electrophoresis technique. The growth inhibition of both VOLph and CuLph complexes against microbial and cancer cells was measured, and the inhibition action, MIC, and IC50 were compared to the inhibition action of the free H2Lph ligand. Both VOLph and CuLph showed remarkable interactive binding with ctDNA compared to the free ligand H2Lph, based on Kb = 16.31, 16.04 and 12.41 × 107 mol-1 dm3 and ΔGb≠ = 47.11, -46.89, and -44.05 kJ mol-1 for VOLph, CuLph, and H2Lph, respectively, due to the central metal ion (VIVO and CuII ions). VOLph (with a higher oxidation state of the V4+ ion and oxo-ligand) exhibited enhanced interaction with the ctDNA molecule compared to CuLph, demonstrating the role and type of the central metal ion within the performed electronegative and electrophilic characters.


Assuntos
Anti-Infecciosos , Isatina , Ligantes , Anti-Infecciosos/farmacologia , Bioensaio , Íons
2.
Exp Eye Res ; 234: 109601, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37488008

RESUMO

Bandage contact lenses have an increased affinity to accumulate tear film proteins and bacteria during wear. Among the wide variety of tear film proteins, lysozyme has attracted the most attention for several reasons, including the fact that it is found at a high concentration in the tear film, has exceptional antibacterial and antibiofilm properties, and its significant deposits onto contact lenses. This study aims to evaluate the effect of lysozyme on bacterial biofilm formation on bandage contact lenses. For this purpose, several methods, including microtiter plate test and Colony Forming Unit (CFU) assay have been used to determine antibacterial and antibiofilm characteristics of lysozyme against the two most frequent contact lens-induced bacterial ocular infections, Staphylococcus aureus, and Pseudomonas aeruginosa. The results of these assays demonstrate lysozyme potential to inhibit 57.9% and 80.7% of the growth of S. aureus and P. aeruginosa, respectively. In addition, biofilm formations of P. aeruginosa and S. aureus reduced by 38.3% and 62.7%, respectively due to the antibiofilm effect of lysozyme. SEM and AFM imaging were utilized to visualize lysozyme antibacterial activity and topography changes of the contact lens surface, respectively, in the presence/absence of lysozyme. The results indicated that lysozyme can efficiently attack both gram-positive and gram-negative bacteria and consequently lysozyme-functionalized bandage contact lenses can reduce the risk of ocular infection after eye surgery.


Assuntos
Lentes de Contato Hidrofílicas , Muramidase , Muramidase/farmacologia , Aderência Bacteriana , Antibacterianos/farmacologia , Staphylococcus aureus , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/metabolismo , Pseudomonas aeruginosa , Biofilmes , Bandagens
3.
Molecules ; 27(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36296701

RESUMO

Myrtaceae family is a continuous source of antimicrobial agents. In the search for novel antimicrobial agents against Staphylococcus species, bioactive fractions of Myrtus communis L., growing in the Sardinia island (Italy) have been investigated. Their phytochemical analysis led us to isolate and characterize four alkylphloroglucinol glycosides (1-4), three of them gallomyrtucommulones G-H (1,2), and myrtucommulonoside (4) isolated and characterized for the first time. The structures of the new and known compounds, endopreroxide G3 (5), myricetin-3-O-glycosides (6,7) were determined based on the spectroscopic evidence including 1D-/2D-NMR and HR-MS spectrometry. Enriched fractions as well as pure compounds were tested for their antimicrobial activity by broth micro-dilution assay against Staphylococcus epidermidis and S. aureus. Results reported herein demonstrated that gallomyrtucommulone G (1) showed a selective antimicrobial activity against both S. aureus strains (ATCC 29213 and 43300) until 16 µg/mL while gallomyrtucommulone D (3) showed the best growth inhibition value at 64 µg/mL.


Assuntos
Anti-Infecciosos , Myrtus , Myrtus/química , Floroglucinol/química , Staphylococcus aureus , Staphylococcus , Glicosídeos/farmacologia , Glicosídeos/análise , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Anti-Infecciosos/análise , Antibacterianos/química , Extratos Vegetais/química
4.
Mar Drugs ; 19(5)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922554

RESUMO

Antimicrobial peptides are a class of proteins with antibacterial functions. In this study, the anti-lipopolysaccharide factor isoform 3 gene (ALFPm3), encoding an antimicrobial peptide from Penaeus monodon with a super activity was expressed in Chlamydomonas reinhardtii, which would develop a microalga strain that can be used for the antimicrobial peptide production. To construct the expression cluster, namely pH2A-Pm3, the codon optimized ALFPm3 gene was fused with the ble reporter by 2A peptide and inserted into pH124 vector. The glass-bead method was performed to transform pH2A-Pm3 into C. reinhardtii CC-849. In addition to 8 µg/mL zeocin resistance selection, the C. reinhardtii transformants were further confirmed by genomic PCR and RT-PCR. Western blot analysis showed that the C. reinhardtii-derived ALFPm3 (cALFPm3) was successfully expressed in C. reinhardtii transformants and accounted for 0.35% of the total soluble protein (TSP). Furthermore, the results of antibacterial assay revealed that the cALFPm3 could significantly inhibit the growth of a variety of bacteria, including both Gram-negative bacteria and Gram-positive bacteria at a concentration of 0.77 µM. Especially, the inhibition could last longer than 24 h, which performed better than ampicillin. Hence, this study successfully developed a transgenic C. reinhardtii strain, which can produce the active ALFPm3 driven from P. monodon, providing a potential strategy to use C. reinhardtii as the cell factory to produce antimicrobial peptides.


Assuntos
Antibacterianos/farmacologia , Chlamydomonas reinhardtii/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Penaeidae/metabolismo , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Animais , Antibacterianos/biossíntese , Chlamydomonas reinhardtii/genética , Regulação Bacteriana da Expressão Gênica , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Proteínas Citotóxicas Formadoras de Poros/biossíntese , Proteínas Citotóxicas Formadoras de Poros/genética
5.
Cryobiology ; 97: 168-178, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32464145

RESUMO

Mesenchymal stromal cells (MSCs) have been demonstrated to possess anti-inflammatory and antimicrobial properties and are of interest in biotechnologies that will require cryopreservation. Recently, MSC-like cells were isolated from colostrum and milk. We used an interrupted slow freezing procedure to examine cryoinjury incurred during slow cooling and rapid cooling of MSC-like cells from swine colostrum. Cells were loaded with either dimethyl sulfoxide (Me2SO) or glycerol, cooled to a nucleation temperature, ice-nucleated, and further cooled at 1 °C/min. At several temperatures along the cooling path, cells were either thawed directly, or plunged into liquid nitrogen for storage and later thawed. The pattern of direct-thaw and plunge-thaw responses was used to guide optimization of cryopreservation protocol parameters. We found that both 5% Me2SO (0.65 M, loaded for 15 min on ice) or 5% glycerol (0.55 M, loaded for 1 h at room temperature) yielded cells with high post-thaw membrane integrity when cells were cooled to at least -30 °C before being plunged into, and stored in, liquid nitrogen. Cells cultured post-thaw exhibited osteogenic differentiation similar to fresh unfrozen control. Fresh and cryopreserved MSC-like cells demonstrated antimicrobial activity against S. aureus. Also, the antimicrobial activity of cell-conditioned media was higher when both fresh and cryopreserved MSC-like cells were pre-exposed to S. aureus. Thus, we were able to demonstrate cryopreservation of colostrum-derived MSC-like cells using Me2SO or glycerol, and show that both cryoprotectants yield highly viable cells with osteogenic potential, but that cells cryopreserved with glycerol retain higher antimicrobial activity post-thaw.


Assuntos
Colostro , Criopreservação , Animais , Sobrevivência Celular , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Feminino , Osteogênese , Gravidez , Staphylococcus aureus , Suínos
6.
AAPS PharmSciTech ; 21(7): 246, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32856115

RESUMO

Enterococcus faecalis infections represent a health concern, mainly in oral diseases, in which treatments with chlorhexidine solution (0.2%) are often used; however, it presents high toxicity degree and several side effects. Based on this, the use of natural products as an alternative to treatment has been explored. Nonetheless, plant extracts have poor organoleptic characteristics that impair theirs in natura use. Therefore, this work aimed to evaluate the analytical profile, biological activity, and cytotoxicity in vitro of S. brasiliensis-loaded chitosan microparticles (CMSb) produced using different aspersion flow rates. The analytical fingerprint was obtained by FTIR and NIR spectra. Principal components analysis (PCA) was used to verify the similarity between the samples. The crystallinity degree was evaluated by X-ray diffraction (XRD). Phytochemical screening (PS) was performed to quantify phytocompounds. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC). Antibiofilm activity and bactericidal kinetics against E. faecalis (ATCC 29212 and MB 146-clinical isolated) were also assessed. The hemolytic potential was performed to evaluate the cytotoxicity. Data provided by FTIR, NIR, and PCA analyses revealed chemical similarity between all CMSb. Furthermore, the results from XRD analysis showed that the obtained CMSb present amorphous characteristic. Tannins and polyphenols were accurately quantified by the PS, but methodology limitations did not allow the flavonoid quantification. The low hemolytic potential assay indicates that all samples are safe. Antimicrobial assays revealed that CMSb were able to inhibit not only the E. faecalis ATCC growth but also the biofilm formation. Only one CMSb sample was able to inhibit the clinical strain. These results highlighted the CMSb antimicrobial potential and revealed this system as a promising product to treat infections caused by E. faecalis.


Assuntos
Anacardiaceae , Anti-Infecciosos/administração & dosagem , Quitosana/administração & dosagem , Enterococcus faecalis/efeitos dos fármacos , Microesferas , Extratos Vegetais/administração & dosagem , Administração Oral , Anti-Infecciosos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Enterococcus faecalis/fisiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana/métodos , Tamanho da Partícula , Casca de Planta , Extratos Vegetais/isolamento & purificação
7.
J Exp Pharmacol ; 16: 71-80, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371428

RESUMO

Background: Erianthemum aethiopicum Wiens and Polhill (Loranthaceae) is a parasitic plant native to north eastern Africa and Ethiopia. In Ethiopia, it is traditionally used to treat breast swelling, mastitis, morning illnesses and vomiting. Objective: This study aimed to screen the main phytochemical constituents; determine the total amounts of phenolics, flavonoids, and tannins; and evaluate the antimicrobial (against Escherichia coli, Staphylococcus sciuri, Candida glaebosa and Cryptococcus albidus) and antioxidant (against DPPH radical and ferric ion) activities of E. aethiopicum leaves extracts. Methods: Powdered E. aethiopicum leaves were macerated using n-hexane, chloroform, ethyl acetate, ethanol, and methanol. All crude extracts were qualitatively screened for phytochemical identification. The total phenolic, flavonoid, and condensed tannin contents of the chloroform, ethanol, and methanol extracts were determined by UV-Vis spectrophotometry. The n-hexane, chloroform, and methanol extracts were evaluated for their antimicrobial activity against the aforementioned microbes using agar disc diffusion and broth micro-dilution techniques. Chloroform, ethanol, and methanol extracts were also evaluated for antioxidant activity by DPPH and ferric ion reduction antioxidant power (FRAP) assays. Results: Methanol (17.56 ± 16%) and ethanol (16.45 ± 19%) showed better extraction efficiency. Flavonoids, polyphenols, tannins, terpenoids, saponins, and sterols were detected in all extracts. The highest total content of phenolics (22.63 ± 0.69 mgGAE/gDCE), flavonoids (5.38 ± 0.52 mgCE/gDCE) and tannins (39.18 ± 38 mg CE/g DCE), as milligram of gallic acid and catechin per gram of dried crude extract, were recorded in the methanolic extract. The methanolic extract also presented best anti -DPPH strength (IC50, 4.31 µg/mL) and ferric ion reduction power (absorbance of 0.71) though found weak compared to the ascorbic acid (IC50 of 0.49 µg/mL and absorbance of 0.93, respectively). Conclusion: All evaluated extracts displayed antifungal activity against both Cryptococcus albidus and Candida glaebosa strains (minimum inhibitory concentration values of 12.5-25 mg/mL), whereas they were found to have negligible activity against all tested bacterial strains. This report provides preliminary information for further phytochemical investigation of Erianthemum aethiopicum to isolate potential antioxidant and antifungal compounds.

8.
Cureus ; 16(3): e55686, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38586786

RESUMO

Background Terminalia bellirica leaf extract was used as an herbal to get an aqueous extract of Tb-ZnO-TiO2 (zinc and titanium dioxide) nanoparticles composite, and this was subsequently subjected to an analysis of its antioxidant properties and possible antimicrobial activity against gram-negative and gram-positive bacteria. Employing the 2,2-Diphenyl-1-picrylhydrazyl and hydrogen peroxide assay techniques for antioxidant properties. In addition to their biocompatibility, rapid biodegradability, and low toxicity, herbal-based nanoparticles (Tb-ZnO-TiO2 NPs composite) synthesized by T. bellirica have drawn a lot of interest as promising options for administering drugs and effective antimicrobial applications. Materials and methods The form and dimensions of the dispersion of the synthesized nanoparticles were investigated through scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy, and UV-visible for particle characterization. Nanoparticles were analyzed for antimicrobial activity using the well diffusion method. Ascorbic acid and vitamin E were used as two separate controls for antioxidant assay with different concentrations, and also toxicity assay was done by using zebrafish embryos. Results Tb-ZnO-TiO2 NPs composite were obtained as a powder, the X-beam diffraction (XRD) result revealed a small quantity of impurities and revealed that the structure was spherical in nature. A unique absorption peak for Tb-ZnO-TiO2 NPs composite may be seen in UV-Vis spectroscopy which is in the region of 260 to 320 nm. The Tb-ZnO-TiO2 NPs composite antibacterial efficacy was evaluated and showed noted antibacterial activity and free radical scavenging activity with less toxicity. Conclusion The results demonstrated the Tb-ZnO-TiO2 NPs composite has strong antioxidant qualities and enormous antibacterial activity obtained from T. bellirica extract. Therefore, the Tb-ZnO-TiO2 NPs composite synthesized nanoparticles can be used in biomedical applications as an effective antioxidant and antibacterial reagent.

9.
Eur J Microbiol Immunol (Bp) ; 14(2): 97-115, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38648108

RESUMO

Infectious diseases pose a formidable global challenge, compounded by the emergence of antimicrobial resistance. Consequently, researchers are actively exploring novel antimicrobial compounds as potential solutions. This endeavor underscores the pivotal role of methods employed for screening and evaluating antimicrobial activity-a critical step in discovery and characterization of antimicrobial agents. While traditional techniques such as well-diffusion, disk-diffusion, and broth-dilution are commonly utilized in antimicrobial assays, they may encounter limitations concerning reproducibility and speed. Additionally, a diverse array of antimicrobial assays including cross-streaking, poisoned-food, co-culture, time-kill kinetics, resazurin assay, bioautography, etc., are routinely employed in antimicrobial evaluations. Advanced techniques such as flow-cytometry, impedance analysis, and bioluminescent technique may offer rapid and sensitive results, providing deeper insights into the impact of antimicrobials on cellular integrity. However, their higher cost and limited accessibility in certain laboratory settings may present challenges. This article provides a comprehensive overview of assays designed to characterize antimicrobial activity, elucidating their underlying principles, protocols, advantages, and limitations. The primary objective is to enhance understanding of the methodologies designed for evaluating antimicrobial agents in our relentless battle against infectious diseases. By selecting the appropriate antimicrobial testing method, researchers can discern suitable conditions and streamline the identification of effective antimicrobial agents.

10.
J Biomol Struct Dyn ; : 1-21, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37477261

RESUMO

A series of new quinoline derivatives has been designed, synthesized and evaluated as antibacterial and antifungal agents functioning as peptide deformylase enzyme (PDF) inhibitors and fungal cell wall disruptors on the basis of computational and experimental methods. The molecular docking and ADMET assessment aided in the synthesis of quinoline derivatives starting from 6-amino-4-methyl-1H-quinoline-2-one substituted with different types of sulfonyl/benzoyl/propargyl moieties. These newly synthesized compounds were evaluated for their in vitro antibacterial and antifungal activity. Antibacterial screening of all compounds showed excellent MIC value (MIC, 50 - 3.12 µg/mL) against bacterial strains, viz. Bacillus cerus, Staphylococcus, Pseudomonas and Escherichia coli. Compounds 2 and 6 showed better activity. Fractional inhibitory concentration (FIC) values of compounds were lowered by 1/2 to 1/128 of the original MIC values when a combinatorial screening with reference drugs was performed. Further, antifungal screening against fungal strains, viz. A. flavus, A. niger, F. oxysporum and C. albicans also showed that all compounds were potentially active and compound 6 being the most potent. Further, the cytotoxicity experiments revealed that compound 6 was the least toxic molecule. The molecular dynamics (MD) simulation investigations elucidated the conformational stability of compound 6-PDF complex with flexible binding pocket residues. The highest number of stable hydrogen bonds with the PDF residues during the entire simulation time illustrated strong binding affinity of compound 6 with PDF.Communicated by Ramaswamy H. Sarma.

11.
Micromachines (Basel) ; 14(7)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37512596

RESUMO

The current study attempts to evaluate the formation, morphology, and physico-chemical properties of zinc oxide nanoparticles (ZnO NPs) synthesized from Clinopodium vulgare extract at different pH values and to investigate their antimicrobial and biomedical application potential. The reduction of zinc ions to ZnO NPs was determined by UV spectra, which revealed absorption peaks at 390 nm at pH 5 and 348 nm at pH 9, respectively. The spherical morphology of the nanoparticles was observed using scanning electron microscopy (SEM), and the size was 47 nm for pH 5 and 45 nm for pH 9. Fourier-transformed infrared spectroscopy (FTIR) was used to reveal the presence of functional groups on the surface of nanoparticles. The antibacterial activity was examined against Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumonia via the agar-well diffusion method. Comparatively, the highest activities were recorded at pH 9 against all bacterial strains, and among these, biogenic ZnO NPs displayed the maximum inhibition zone (i.e., 20.88 ± 0.79 mm) against S. aureus. ZnO NPs prepared at pH 9 exhibited the highest antifungal activity of 80% at 25 mg/mL and antileishmanial activity of 82% at 400 mg/mL. Altogether, ZnO NPs synthesized at pH 9 show promising antimicrobial potential and could be used for biomedical applications.

12.
Plants (Basel) ; 12(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38005733

RESUMO

Indonesia is among the countries with the most significant biodiversity globally. Jamu, the traditional medicine of Indonesia, predominantly uses herbal materials and is an integral component of the Indonesian healthcare system. The present study reviewed the ethnobotanical data of seven Indonesian Euphorbiaceae species, namely Euphorbia atoto, E. hypericifolia, Homalanthus giganteus, Macaranga tanarius, Mallotus mollissimus, M. rufidulus, and Shirakiopsis indica, based on the RISTOJA database and other literature sources. An antimicrobial screening of the plant extracts was performed in 15 microorganisms using the disk diffusion and broth microdilution methods, and the antiproliferative effects were examined in drug-sensitive Colo 205 and resistant Colo 320 cells by the MTT assay. The antimicrobial testing showed a high potency of M. tanarius, H. giganteus, M. rufidulus, S. indica, and E. atoto extracts (MIC = 12.5-500 µg/mL) against different bacteria. In the antitumour screening, remarkable activities (IC50 0.23-2.60 µg/mL) were demonstrated for the extracts of H. giganteus, M. rufidulus, S. indica, and E. atoto against Colo 205 cells. The n-hexane extract of E. atoto, with an IC50 value of 0.24 ± 0.06 µg/mL (Colo 205), was subjected to multistep chromatographic separation, and 24-methylene-cycloartan-3ß-ol, jolkinolide E, tetra-tert-butyl-diphenyl ether, α-tocopherol, and ß-sitosterol were isolated.

13.
Int J Biol Macromol ; 249: 125917, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37524289

RESUMO

Two novel divalent bimetallic complexes were constructed from the complexation of O=V4+ and Zn2+ ions (VOL and ZnL), respectively, with diisatin oxalyldihydrazone ligand (H2L). Various spectroscopic tools were used to confirm their chemical structures (FT-IR, NMR, EI-Mass, and electronic spectra), besides, elemental analyses and conductivity features. To estimate the role of divalent metal ions in their coordination compound for developing their bio-reactivity, the free ligand H2Lox, and its complexes (VOL and ZnL) were employed spectroscopic investigations against the growth of some microbial series (fungi and bacteria) and also against three human cancer/normal cells. Furthermore, their interaction behavior against calf thymus DNA (ctDNA) was studied through viscometric and spectrophotometric studies to discover the role of O=V4+ and Zn2+ ions to determine the mode of binding with ctDNA. The inhibiting effect of H2L, VOL, and ZnL versus the titled microbial (bacterial and fungal) was built upon their inhibited zone areas in mm and the MIC concentrations in µM. Their action against the three human cancer cells' growth was evaluated by IC50 values in µM and the selectivity index in percentage. Both VOL and ZnL complexes exhibited an amazing series with three human cancer cell growth (according to the zone values in mm of inhibition, MIC in µM, and IC50 values in µM) compared to those of their uncoordinated H2L ligand. VOL demonstrated a distinguished interacting behavior with ctDNA more than that interaction of ZnL depending on the variation of the central metal ion chemical features. Within the covalent and non-covalent interaction modes, the interaction binding between H2L, VOL, and ZnL with ctDNA was discussed based on the electronic spectroscopic observation.


Assuntos
Complexos de Coordenação , Neoplasias , Humanos , Zinco/química , Vanadatos/farmacologia , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Ligantes , Espectroscopia de Infravermelho com Transformada de Fourier , Bactérias , Testes de Sensibilidade Microbiana
14.
Chemosphere ; 338: 139584, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37478987

RESUMO

In this study, the naturally available Ziziphus Mauritiana was used as a bioresource for the preparation of bifunctional nitrogen doped carbon dots (N-CDs). The doping of nitrogen into the graphitic carbon skeleton and the in-situ formation of N-CDs were systematically identified by the various structural and morphological studies. The green fluorescent N-CDs were used as active catalysts for the removal of Safranin-O dye and achieved 79 % removal efficiency. Furthermore, the prepared N-CDs were used to evaluate antibacterial activity with four different bacterial species, such as Shigella flexneri, Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumoniae. Amongst these, the highest antimicrobial activity was achieved against Klebsiella pneumonia, with a maximum zone of inhibition of 14.6 ± 1.12 at a concentration of 100 g mL-1. Thus, the obtained results demonstrate the cost efficient bifunctional application prospects of N-CDs to achieve significant catalytic and antibacterial activities.


Assuntos
Grafite , Pontos Quânticos , Ziziphus , Carbono/química , Nitrogênio/química , Catálise , Pontos Quânticos/química , Corantes Fluorescentes/química
15.
Heliyon ; 8(4): e09209, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35399375

RESUMO

Highly efficient and durable, silver nanoparticles doped Active Carbon Spheres ACS(Ag) were synthesized by carbonization and activation of silver exchanged resins. The silver exchanged resins were prepared by exchanging H+ ions of polystyrene sulphonate resin with Ag+ ions of silver nitrate (AgNO3). The quantity of Ag+ in the spheres was controlled by varying the concentration of AgNO3, from 0.0125 to 0.1 M. With increasing molar concentration of AgNO3, the effective intake of Ag+ by the sphere increases from 1.1 to 8.1 weight percent (wt %). For activation, the spheres were incubated in the CO2 atmosphere for 6 h at fixed soaking temperature i.e. 1123 K. The characterization of synthesized silver doped ACS was performed by using different sophisticated instrumental techniques. The antimicrobial activity of silver doped ACS was studied against different bacterial strains like, E. coli, B. subtilis and Staphylococcus aureus. The study demonstrated that the zone of inhibition for E. coli was 16.9 ± 0.7 mm while for B. subtilis it was 17.1 ± 0.3 mm at a concentration of 8 mg of synthesized material. In addition, satisfactory results were obtained in shake flask and filtration test experiments also, even at a low concentration of 2 mg, showing growth inhibition of 94% for E. coli and 93% for B. subtilis. When the concentration of silver doped ACS was increased to 8 mg, complete removal of both the bacteria was observed after 24 h (100 % reduction for E. coli and B. subtilis). Furthermore, when silver doped ACS was tested against Staphylococcus aureus according to ASTM:E 2149-01 method, biocidal activity of up to 73% was observed. Therefore, the silver doped ACS can be considered as a potential biocidal material for the studied bacterial strains and hence find suitable application for decontamination of water.

16.
Chemosphere ; 287(Pt 4): 132276, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34601372

RESUMO

Phytoconstituents of plants had enormous therapeutic potential against the wounds on skin. Plants like Tecoma stans, Manilkara zapota and Cassia fistula were some which had the ability to heal the wounds. However, there was limited research in Cassia fistula flowers and its synergism with plants on wound healing and its mechanism. Qualitative analysis was performed to confirm the presence of phytoconstituents like flavonoids, saponins and tannins in solvents:aqueous ethanol and methanol. All three components showed their attributes towards wound healing. Results of antimicrobial activity clearly stated that, methanol extract of the Cassia fistula flowers at increasing concentration, showed the maximum zone of inhibition of 27 mm at 100 µl (antibacterial assay) and 18 mm at 100 µl (anti-fungal assay). They had higher potential against the selective microbes Staphylococcus aureus and Aspergillus niger. The combination of C. fistula flowers and C. fistula leaves; C. fistula flowers and M. zapota leaves showed maximum zone of inhibition of 23 mm and 21 mm for anti-bacterial; 22 mm and 23 mm for antifungal at 100 µl respectively. The C. fistula flowers along with the Manilkara zapota leaves and C. fistula leaves enhanced the antimicrobial nature than the individual plants. The antimicrobial properties present in the plants would engage them in future for developing an improved medicine for wound healing. Thus a polyherbal plant solution containing equal proportions of plants, tested for the antibacterial activity, succeeded by showing its higher inhibition of 25 mm at 100 µl.This concluded that the synergism of plants had higher efficiency in microbial activity than the individual samples hence proving the plants attributes towards the wound healing.


Assuntos
Anti-Infecciosos , Bignoniaceae , Plantas Medicinais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Folhas de Planta
17.
Vaccines (Basel) ; 10(8)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36016184

RESUMO

Microbial resistance is a global health problem that will increase over time. Advances in insect antimicrobial peptides (AMPs) offer a powerful new approach to combat antimicrobial resistance. Invertebrates represent a rich group of animals for the discovery of new antimicrobial agents due to their high diversity and the presence of adaptive immunity or "immune priming". Here, we report a priming approach for Tenebrio molitor that simulates natural infection via the oral route. This oral administration has the advantage of minimizing the stress caused by conventional priming techniques and could be a viable method for mealworm immunity studies. When using inactivated microorganisms for oral priming, our results showed an increased survival of T. molitor larvae after exposure to various pathogens. This finding was consistent with the induction of antimicrobial activity in the hemolymph of primed larvae. Interestingly, the hemolymph of larvae orally primed with Escherichia coli showed constitutive activity against Staphylococcus aureus and heterologous activity for other Gram-negative bacteria, such as Salmonella enterica. The priming of T. molitor is generally performed via injection of the microorganism. To our knowledge, this is the first report describing the oral administration of heat-inactivated microorganisms for priming mealworms. This technique has the advantage of reducing the stress that occurs with the conventional methods for priming vertebrates.

18.
J Biomater Sci Polym Ed ; 32(4): 438-453, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33091325

RESUMO

This article describes synthesis, characterization, antimicrobial, drug-releasing and anti-cancer activity of acrylate monomer and its polymer containing chalcone moiety. The synthesized polymers were characterized through IR, 1H NMR and UV-visible spectroscopy techniques. The molecular weight of the obtained polymer is found to be around 4000 g/mol. The synthesized polymers are thermally stable up to 260 °C. The monomer and its polymer show higher activity against gram-negative bacteria and these compounds show remarkable activity over breast cancer cells. The synthesized monomer and polymers showed higher anticancer activity. The inhibitory potential of monomers and polymers premeditated using optimized in vitro evaluation MTT assay and live cell images. The drug release potential was controlled through co-monomer, pH and temperature.


Assuntos
Anti-Infecciosos , Chalcona , Chalconas , Acrilatos , Anti-Infecciosos/farmacologia , Liberação Controlada de Fármacos , Polímeros
19.
Int J Biol Macromol ; 145: 42-52, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31846659

RESUMO

Membranes were fabricated from a blend of synthetic copolymer (thiourea, phenylhydrazine and formaldehyde) and chitosan to study the metformin drug release profile and its kinetics. The membranes were characterized with elemental, scanning electron microscopy, FTIR and 1H NMR spectroscopy to identify the empirical formula & weight, surface morphology and functional group changes occurred during the incorporation of chitosan to the copolymer. The swelling behaviour, drug loading efficiency and drug release profile of the membranes were studied using UV-visible spectroscopy. The mechanical properties and in vitro degradation studies were also performed. The reactive sites, better porosity and larger surface area provided by chitosan to the copolymer led to higher drug loading efficiency and controlled drug release profile. Kinetic study revealed swelling and diffusion controlled mechanism for the membranes, which obtained from Ritger-Peppas and Higuchi model. The chitosan and its copolymer membranes were tested for antimicrobial assay using selective gram-positive and gram-negative bacterial and fungal strains. The CS-TPF-drug membranes showed an acceptable control of the growth of all the microbial species compared to CS, CS-drug and the standard metformin drug.


Assuntos
Anti-Infecciosos/química , Quitosana/química , Liberação Controlada de Fármacos , Hipoglicemiantes/química , Membranas/química , Polímeros/química , Varredura Diferencial de Calorimetria/métodos , Preparações de Ação Retardada/química , Difusão , Sistemas de Liberação de Medicamentos/métodos , Cinética , Microscopia Eletrônica de Varredura/métodos , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
20.
Photodiagnosis Photodyn Ther ; 32: 102058, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33065306

RESUMO

Copper nanoparticles were synthesized using Manilkara zapota leaf extract. The synthesis of the nanoparticle was primarily visualized when the colour of the reaction mixture turned into reddish-brown. Biosynthesized nanoparticles were characterized by UV-vis, FT-IR, XRD, SEM and EDX. The UV spectra showed maximum absorption at 584 nm. FT-IR studies showed stretching frequency at 592.76 cm-1, which is the fingerprint region for Cu-O bond. The crystallinity of the synthesized copper nanoparticles (Mz-Cu NPs) was revealed through XRD analysis. The synthesized Mz-Cu NPs were spherical with an average size of 18.9-42.5 nm and it was shown by SEM analysis. EDX analysis displayed that the nano sample contains 58 % of copper. The antimicrobial property of the synthesized nanoparticles was evaluated against fungal plant pathogens Rhizoctonia solani (MTCC 12232), Sclerotium oryzae (MTCC 12230) and bacterial species, namely Bacillus subtilis (ATCC 23857), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Vibrio harveyi (ATCC 35084), Vibrio parahaemolyticus (ATCC 33845). In in-vitro haemolytic assay, the particle showed 5.73, 3.34, 0.5 % hemolysis at 100, 50, 25 µg/mL concentration respectively. In the antiproliferative assay, the IC50 values of MCF7 and Vero cells were found to be 53.89 and 883.69 µg/µl. The particle degraded Methyl violet, Malachite green and Coomassie brilliant blue by 92.2, 94.9 and 78.8 %, within 50, 40 and 60 min, respectively, through its photocatalytic activity.


Assuntos
Anti-Infecciosos , Manilkara , Nanopartículas Metálicas , Fotoquimioterapia , Animais , Antibacterianos/farmacologia , Ascomicetos , Chlorocebus aethiops , Cobre/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Extratos Vegetais/farmacologia , Rhizoctonia , Espectroscopia de Infravermelho com Transformada de Fourier , Células Vero , Vibrio
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