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result(s) for
"Al-Otibi, Fatimah"
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Facile Green Synthesis of Silver Nanoparticles Using Aqueous Leaf Extract of Origanum majorana with Potential Bioactivity against Multidrug Resistant Bacterial Strains
by
Mostafa, Ashraf Abdel-Fattah
,
Yassin, Mohamed Taha
,
Al-Otibi, Fatimah O.
in
Aluminum
,
Antibiotics
,
Antimicrobial agents
2022
The high prevalence of nosocomial bacterial resistance contributes to significant mortality and morbidity around the world; thus, finding novel antibacterial agents is of vital concern. Accordingly, the present study attempted to synthesize silver nanoparticles (AgNPs) using a green approach. Aqueous leaf extract of Origanum majorana was used to synthesize AgNPs and the antibacterial efficiency against multidrug resistant bacterial strains was detected. Characterization of the biogenic AgNPs was performed using ultraviolet-visible spectrophotometry (UV-Vis), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR) analysis, and X-ray diffraction analysis (XRD). The disc diffusion method was used to detect the antibacterial activity of AgNPs against three nosocomial multidrug-resistant strains. Preliminary UV-Vis analysis revealed the biosynthesis of AgNPs due to peak formation at 374 nm, corresponding to the surface plasmon resonance (SPR) of biogenic AgNPs. TEM micrographs detected the synthesis of small AgNPs with an average particle size of 26.63 nm. EDX analysis revealed the presence of the following elements: oxygen (3.69%), carbon (2.93%), aluminum (1.29), silicon (2.83%), chloride (17.89%), and silver (71.37%). Furthermore, XRD analysis revealed the presence of diffraction peaks at 2 theta (θ) degrees of 38.18°, 44.36°, 64.35°, and 77.54°, assigned to the planes of silver crystals (111), (200), (220), and (311), respectively. Collectively, these findings affirm the synthesis of biogenic AgNPs with potential physicochemical characteristics. The antimicrobial efficiency of the biogenic AgNPs indicated that Klebsiella pneumoniae strain was the most susceptible strain at concentrations of 50 and 100 µg/disk, with inhibitory zones of 21.57 and 24.56 mm, respectively. The minimum inhibitory concentration (MIC) of AgNPs against Klebsiella pneumoniae strain was found to be 10 µg/mL, while the minimum bactericidal concentration (MBC) was found to be 20 µg/mL. In conclusion, aqueous leaf extract of O. majorana mediated synthesis of small sized AgNPs, with potential antimicrobial effectiveness against multidrug-resistant bacterial pathogens.
Journal Article
Green Biofabrication of Silver Nanoparticles of Potential Synergistic Activity with Antibacterial and Antifungal Agents against Some Nosocomial Pathogens
by
Maniah, Khalid
,
Al-Askar, Abdulaziz A.
,
Yassin, Mohamed Taha
in
Acinetobacter baumannii
,
Antibacterial activity
,
antibacterial properties
2023
Nosocomial bacterial and fungal infections are one of the main causes of high morbidity and mortality worldwide, owing to the high prevalence of multidrug-resistant microbial strains. Hence, the study aims to synthesize, characterize, and investigate the antifungal and antibacterial activity of silver nanoparticles (AgNPs) fabricated using Camellia sinensis leaves against nosocomial pathogens. The biogenic AgNPs revealed a small particle diameter of 35.761 ± 3.18 nm based on transmission electron microscope (TEM) graphs and a negative surface charge of −14.1 mV, revealing the repulsive forces between nanoparticles, which in turn indicated their colloidal stability. The disk diffusion assay confirmed that Escherichia coli was the most susceptible bacterial strain to the biogenic AgNPs (200 g/disk), while the lowest sensitive strain was found to be the Acinetobacter baumannii strain with relative inhibition zones of 36.14 ± 0.67 and 21.04 ± 0.19 mm, respectively. On the other hand, the biogenic AgNPs (200 µg/disk) exposed antifungal efficacy against Candida albicans strain with a relative inhibition zone of 18.16 ± 0.14 mm in diameter. The biogenic AgNPs exposed synergistic activity with both tigecycline and clotrimazole against A. baumannii and C. albicans, respectively. In conclusion, the biogenic AgNPs demonstrated distinct physicochemical properties and potential synergistic bioactivity with tigecycline, linezolid, and clotrimazole against gram-negative, gram-positive, and fungal strains, respectively. This is paving the way for the development of effective antimicrobial combinations for the effective management of nosocomial pathogens in intensive care units (ICUs) and health care settings.
Journal Article
Facile Green Synthesis of Zinc Oxide Nanoparticles with Potential Synergistic Activity with Common Antifungal Agents against Multidrug-Resistant Candidal Strains
by
Mostafa, Ashraf Abdel-Fattah
,
Yassin, Mohamed Taha
,
Al-Otibi, Fatimah O.
in
Absorption
,
Aluminum
,
antifungal
2022
The high incidence of fungal resistance to antifungal drugs represents a global concern, contributing to high levels of morbidity and mortality, especially among immunocompromised patients. Moreover, conventional antifungal medications have poor therapeutic outcomes, as well as possible toxicities resulting from long-term administration. Accordingly, the aim of the present study was to investigate the antifungal effectiveness of biogenic zinc oxide nanoparticles (ZnO NPs) against multidrug-resistant candidal strains. Biogenic ZnO NPs were characterized using physicochemical methods, such as UV-vis spectroscopy, transmission electron microscopy (TEM), energy-dispersive X ray (EDX) spectroscopy, FTIR (Fourier transform infrared) spectroscopy and X-ray powder diffraction (XRD) analysis. UV spectral analysis revealed the formation of two absorption peaks at 367 and 506 nm, which preliminarily indicated the successful synthesis of ZnO NPs, whereas TEM analysis showed that ZnO NPs exhibited an average particle size of 22.84 nm. The EDX spectrum confirmed the successful synthesis of ZnO nanoparticles free of impurities. The FTIR spectrum of the biosynthesized ZnO NPs showed different absorption peaks at 3427.99, 1707.86, 1621.50, 1424.16, 1325.22, 1224.67, 1178.22, 1067.69, 861.22, 752.97 and 574.11 cm−1, corresponding to various functional groups. The average zeta potential value of the ZnO NPs was −7.45 mV. XRD analysis revealed the presence of six diffraction peaks at 2θ = 31.94, 34.66, 36.42, 56.42, 69.54 and 76.94°. The biogenic ZnO NPs (100 µg/disk) exhibited potent antifungal activity against C. albicans, C. glabrata and C. tropicalis strains, with suppressive zone diameters of 24.18 ± 0.32, 20.17 ± 0.56 and 26.35 ± 0.16 mm, respectively. The minimal inhibitory concentration (MIC) of ZnO NPs against C. tropicalis strain was found to be 10 μg/mL, whereas the minimal fungicidal concentration (MFC) was found to be 20 μg/mL. Moreover, ZnO NPs revealed a potential synergistic efficiency with fluconazole, nystatin and clotrimazole antifungal drugs against C. albicans strain, whereas terbinafine, nystatin and itraconazole antifungal drugs showed a potential synergism with ZnO NPs against C. glabrata as a multidrug-resistant strain. In conclusion, pomegranate peel extract mediated green synthesis of ZnO NPs with potential physicochemical features and antimicrobial activity. The biosynthesized ZnO NPs could be utilized for formulation of novel drug combinations to boost the antifungal efficiency of commonly used antifungal agents.
Journal Article
A comparative study using response surface methodology and artificial neural network towards optimized production of melanin by Aureobasidium pullulans AKW
by
Saber, WesamEldin I. A.
,
Eldadamony, Noha M.
,
Menaa, Farid
in
631/326
,
631/61
,
Aureobasidium pullulans
2023
The effect of three independent variables (i.e., tyrosine, sucrose, and incubation time) on melanin production by
Aureobasidium pullulans
AKW was unraveled by two distinctive approaches: response surface methodology (i.e. Box Behnken design (BBD)) and artificial neural network (ANN) in this study for the first time ever using a simple medium. Regarding BBD, sucrose and incubation intervals did impose a significant influence on the output (melanin levels), however, tyrosine did not. The validation process exhibited a high consistency of BBD and ANN paradigms with the experimental melanin production. Concerning ANN, the predicted values of melanin were highly comparable to the experimental values, with minor errors competing with BBD. Highly comparable experimental values of melanin were achieved upon using BBD (9.295 ± 0.556 g/L) and ANN (10.192 ± 0.782 g/L). ANN accurately predicted melanin production and showed more improvement in melanin production by about 9.7% higher than BBD. The purified melanin structure was verified by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction pattern (XRD), and thermogravimetric analysis (TGA). The results verified the hierarchical architecture of the particles as small compasses by SEM analysis, inter-layer spacing in the XRD analysis, maximal atomic % for carbon, and oxygen atoms in the EDX analysis, and the great thermal stability in the TGA analysis of the purified melanin. Interestingly, the current novel endophytic strain was tyrosine-independent, and the uniquely applied ANN paradigm was more efficient in modeling the melanin production with appreciate amount on a simple medium in a relatively short time (168 h), suggesting additional optimization studies for further maximization of melanin production.
Journal Article
Synergistic Antifungal Efficiency of Biogenic Silver Nanoparticles with Itraconazole against Multidrug-Resistant Candidal Strains
by
Mostafa, Ashraf Abdel-Fattah
,
Yassin, Mohamed Taha
,
Al-Otibi, Fatimah O.
in
antifungal activity
,
Antifungal agents
,
Antimicrobial agents
2022
Fungal infections caused by multidrug-resistant strains are considered one of the leading causes of morbidity and mortality worldwide. Moreover, antifungal medications used in conventional antifungal treatment revealed poor therapeutic effectiveness and possible side effects such as hepatotoxicity, nephrotoxicity, and myelotoxicity. Therefore, the current study was developed to determine the antifungal effectiveness of green synthesized silver nanoparticles (AgNPs) and their synergistic efficiency with antifungal drugs against multidrug-resistant candidal strains. The AgNPs were greenly synthesized using the aqueous peel extract of Punica granatum. In addition, AgNPs were characterized using ultraviolet-visible spectrophotometry (UV/Vis), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), and zeta potential analysis. In this regard, UV-vis analysis indicated SPR of AgNPs at 396 nm, while the particle size distribution revealed that the average particle size was 18.567 ± 1.46 nm. The surface charge of AgNPs was found to be −15.6 mV, indicating their stability in aqueous solutions. The biofabricated AgNPs indicated antifungal activity against Candida tropicalis, C. albicans, and C. glabrata strains showing inhibitory zone diameters of 23.78 ± 0.63, 21.38 ± 0.58, and 16.53 ± 0.21 mm, respectively while their minimum inhibitory concentration (MIC) was found to be 2.5 µg/mL against C. tropicalis strain. AgNPs and itraconazole revealed the highest synergistic activity against the multidrug-resistant strain, C. glabrata, recording a synergism percentage of 74.32%. In conclusion, the biogenic AgNPs in combination with itraconazole drug exhibited potential synergistic activity against different candidal strains indicating their potential usage in the bioformulation of highly effective antifungal agents.
Journal Article
Synergistic Antibacterial Activity of Green Synthesized Silver Nanomaterials with Colistin Antibiotic against Multidrug-Resistant Bacterial Pathogens
by
Mostafa, Ashraf Abdel-Fattah
,
Yassin, Mohamed Taha
,
Al-Otibi, Fatimah O.
in
Antibacterial agents
,
Antibacterial materials
,
Antibiotics
2022
The high frequency of nosocomial bacterial infections caused by multidrug-resistant pathogens contributes to significant morbidity and mortality worldwide. As a result, finding effective antibacterial agents is of critical importance. Hence, the aim of the present study was to greenly synthesize silver nanoparticles (AgNPs) utilizing Salvia officinalis aqueous leaf extract. The biogenic AgNPs were characterized utilizing different physicochemical techniques such as energy-dispersive X-ray spectroscopy (EDX), ultraviolet-visible spectrophotometry (UV-Vis), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) analysis. Additionally, the synergistic antimicrobial effectiveness of the biosynthesized AgNPs with colistin antibiotic against multidrug-resistant bacterial strains was evaluated utilizing the standard disk diffusion assay. The bioformulated AgNPs revealed significant physicochemical features, such as a small particle size of 17.615 ± 1.24 nm and net zeta potential value of −16.2 mV. The elemental mapping of AgNPs revealed that silver was the main element, recording a relative mass percent of 83.16%, followed by carbon (9.51%), oxygen (5.80%), silicon (0.87%), and chloride (0.67%). The disc diffusion assay revealed that AgNPs showed antibacterial potency against different tested bacterial pathogens, recording the highest efficiency against the Escherichia coli strain with an inhibitory zone diameter of 37.86 ± 0.21 mm at an AgNPs concentration of 100 µg/disk. In addition, the antibacterial activity of AgNPs was significantly higher than that of colistin (p ≤ 0.05) against the multidrug resistant bacterial strain namely, Acinetobacter baumannii. The biosynthesized AgNPs revealed synergistic antibacterial activity with colistin antibiotic, demonstrating the highest synergistic percent against the A. baumannii strain (85.57%) followed by Enterobacter cloacae (53.63%), E. coli (35.76%), Klebsiella pneumoniae (35.19%), Salmonella typhimurium (33.06%), and Pseudomonas aeruginosa (13.75%). In conclusion, the biogenic AgNPs revealed unique physicochemical characteristics and significant antibacterial activities against different multidrug-resistant bacterial pathogens. Consequently, the potent synergistic effect of the AgNPs–colistin combination highlights the potential of utilizing this combination for fabrication of highly effective antibacterial coatings in intensive care units for successful control of the spread of nosocomial bacterial infections.
Journal Article
Green Synthesis of Zinc Oxide Nanocrystals Utilizing Origanum majorana Leaf Extract and Their Synergistic Patterns with Colistin against Multidrug-Resistant Bacterial Strains
by
Maniah, Khalid
,
Yassin, Mohamed Taha
,
Al-Otibi, Fatimah O.
in
Antibacterial materials
,
Antibiotics
,
Bacteria
2022
There is a crucial necessity for the formulation of efficient antimicrobial agents owing to the increasing prevalence of hospital-acquired bacterial infections triggered by multidrug-resistant microbes that result in significant deaths and illnesses around the world. Hence, the current investigation examined the antibacterial proficiency of zinc oxide nanoparticles formulated utilizing the green route against bacterial strains that were resistant to multiple drugs. In addition, the synergistic antibacterial action of ZnO nanoparticles (ZnO NPs) combined with colistin was investigated against the tested microbial strains to determine the efficiency of the bioinspired ZnO nanoparticles in boosting the antibacterial proficiency of colistin antibiotic. Incidentally, the bioinspired ZnO nanoparticles were synthesized using water extract of Origanum majorana leaves and these nanomaterials were physicochemically characterized using different analytical techniques. The bioactivity of the synthesized nanomaterials against multidrug-resistant bacterial strains was appraised using the agar diffusion method. The biogenic ZnO NPs at a concentration of 100 μg/disk revealed a compelling antimicrobial efficacy against the tested strains, expressing the maximum antimicrobial action against Escherichia coli strain with clear zone diameter of 38.16 ± 0.18 mm. The remarkable antibacterial proficiency might be accredited to the tiny particle size of the bioformulated ZnO NPs of 12.467 ± 1.36 nm. The net charge of ZnO nanomaterials was −14.8 mV while XRD analysis confirmed their hexagonal wurtzite structure. Furthermore, the bioformulated ZnO NPs showed a promising synergistic potency with colistin demonstrating respective synergism proportions of 91.05, 79.07, 75.04, 75.25, 56.28 and 10.60% against E. coli, Klebsiella pneumoniae, Acinetobacter baumannii, Salmonella typhimurium, Enterobacter cloacae, and Pseudomonas aeruginosa, respectively. In conclusion, the water extract of O. majorana leaves mediated green formulation of zinc oxide nanoparticles with unique physicochemical characteristics and effective antibacterial proficiency against the examined drug-resistant bacterial strains. These nanomaterials could be used in the synthesis of effective antibacterial coatings to control hospital acquired infections caused by multidrug-resistant bacterial pathogens.
Journal Article
Ameliorative Effect of Beta vulgaris Root Extract on Chlorpyrifos-Induced Oxidative Stress, Inflammation and Liver Injury in Rats
by
Almeer, Rafa
,
Mahmoud, Ayman M.
,
Albasher, Gadah
in
Animals
,
Antioxidants - analysis
,
Antioxidants - metabolism
2019
Exposure to organophosphorus insecticides causes several health problems to animals and humans. Red beetroot (RBR) is rich in antioxidant ingredients and possesses a promising hepatoprotective activity. This study evaluated the potential of RBR extract to prevent chlorpyrifos (CPF)-induced liver injury, with an emphasis on oxidative stress, inflammation and apoptosis. Rats received 10 mg/kg CPF and were treated with 300 mg/kg RBR extract for 28 days. CPF caused liver injury evidenced by elevated serum levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and bilirubin, along with several histological alterations. Hepatic lipid peroxidation (LPO) and nitric oxide (NO) levels, as well as inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines were increased in CPF-intoxicated rats. RBR prevented CPF-induced histological alterations, and ameliorated liver function, LPO, NO, iNOS and pro-inflammatory cytokines. RBR boosted glutathione and antioxidant enzymes, and increased Nrf2 expression. In addition, RBR diminished Bax and caspase-3, and increased Bcl-2 expression. In conclusion, RBR prevented CPF-induced liver injury via attenuation of oxidative stress, inflammation and apoptosis. RBR enhanced antioxidant defenses, suggesting that it could be used as a potential therapeutic intervention to minimize CPF hepatotoxicity.
Journal Article
Morphology and Multi-Gene Phylogeny Reveal a New Species of Family Torulaceae from Yunnan Province, China
by
Zhao, Qi
,
Bhunjun, Chitrabhanu S.
,
Hyde, Kevin D.
in
1 new species
,
Aquatic habitats
,
asexual fungi
2024
The Family Torulaceae belongs to the Order Pleosporales (Class Dothideomycetes) and mainly comprises saprobes. The taxa are widely distributed in both terrestrial and aquatic habitats. In this study, we collected three dead leaf specimens of Carex baccans and two submerged wood specimens in Yunnan Province, China. A biphasic approach of morphological examination and multi-locus phylogenetic analyses conducted for internal transcribed spacer region ITS1-5.8S-ITS2 (ITS), nuclear large subunit rDNA (28S), nuclear small subunit rDNA (18S), translation elongation factor 1-α (tef1) gene, and RNA polymerase II second-largest subunit (rpb2) revealed one new species Rutola kunmingensis and a new collection of Torula sundara. Rutola kunmingensis is characterized by black, powdery colonies, micronematous, creeping, reticular conidiophores bearing inconspicuous, monoblastic conidiogenous loci, and multi-septate, catenulate, verruculose, brown conidia. The conidiophores and conidia of each genus in Torulaceae are mapped onto the phylogenetic tree and the generic demarcations of this family are discussed and the significant divergence of ITS, 18S, 28S, rpb2, and tef1 sequences in Torulaceae is also discussed.
Journal Article
Phytogenic Synthesis and Characterization of Silver Metallic/Bimetallic Nanoparticles Using Beta vulgaris L. Extract and Assessments of Their Potential Biological Activities
by
Ghoniem, Abeer A.
,
Helmy, Yosra A.
,
Saber, WesamEldin I. A.
in
antioxidant activity
,
Apoptosis
,
biological assessments
2023
The synthesis of novel nanomedicines through eco-friendly protocols has been applied on a large scale with the prediction of discovering alternate therapies. The current work attained phytogenic synthesis of Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs through bio-reduction using an aqueous extract of Beta vulgaris (red beetroot). The phytochemical profile of the eco-friendly synthesized metallic/bimetallic nanoparticles was studied. The optical properties of nano-solutions were studied via UV-visible spectroscopy. The Fourier-transform infrared spectroscopy (FT-IR) spectral analyses revealed that stretching vibrations at wavenumbers 3303.81–3327.81 cm−1 attributed to phenolic hydroxyl groups documented shifts in the values in this range owing to proton dissociation through the bio-reduction of the metal ions. The surface morphology and the charge of the nanoparticles were investigated using a Transmission Electron Microscope (TEM) and zeta potential analyses. The prepared nano-solutions showed lower antioxidant activity (1,1-Diphenyl-2-picrylhydrazyl (DPPH•) and phosphomolybdate assays) than the plant extract. These results together with phytochemical analyses support the participation of the reactive species (phenolic contents) in the bio-reduction of the metal ions in the solutions through the formation of metallic/bimetallic nanoparticles. Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs showed antibacterial potentiality. AgSeO2-bmNPs were superior with inhibitory zone diameters of 34.7, 37.7, 11.7, and 32.7 mm against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, and Salmonella enterica, respectively. Applying the Methylthiazole Tetrazolium (MTT) assay, the Ag-TiO2 bmNPs revealed potent cytotoxicity against the HePG2 tumor cell line (IC50 = 18.18 ± 1.5 µg/mL), while Ag-SeO2 bmNPs revealed the most potent cytotoxicity against the MCF-7 cell line (IC50 = 17.92 ± 1.4 µg/mL).
Journal Article