Magnesium oxide nanoparticles (MgO-NPs) were synthesized using the fungal strain Aspergillus terreus S1 to overcome the disadvantages of chemical and physical methods. The factors affecting the ...biosynthesis process were optimized as follows: concentration of Mg(NO3)2·6H2O precursor (3 mM), contact time (36 min), pH (8), and incubation temperature (35 °C). The characterization of biosynthesized MgO-NPs was accomplished using UV-vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy—energy dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), and dynamic light scattering (DLS). Data confirmed the successful formation of crystallographic, spherical, well-dispersed MgO-NPs with a size range of 8.0–38.0 nm at a maximum surface plasmon resonance of 280 nm. The biological activities of biosynthesized MgO-NPs including antimicrobial activity, biotreatment of tanning effluent, and chromium ion removal were investigated. The highest growth inhibition of pathogenic Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans was achieved at 200 μg mL–1 of MgO-NPs. The biosynthesized MgO-NPs exhibited high efficacy to decolorize the tanning effluent (96.8 ± 1.7% after 150 min at 1.0 µg mL–1) and greatly decrease chemical parameters including total suspended solids (TSS), total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and conductivity with percentages of 98.04, 98.3, 89.1, 97.2, and 97.7%, respectively. Further, the biosynthesized MgO-NPs showed a strong potential to remove chromium ions from the tanning effluent, from 835.3 mg L–1 to 21.0 mg L–1, with a removal percentage of 97.5%.
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Bacterial and fungal endophytes are widespread inhabitants inside plant tissues and have been shown to assist plant growth and health. However, little is known about plant ...growth-promoting endophytes (PGPE) of medicinal plants. Therefore, the aims of this study were to identify bacterial and fungal endophytes of Teucrium polium and to characterize plant growth-promoting (PGP) properties of these endophytes. Seven bacterial endophytes were isolated and identified as Bacillus cereus and Bacillus subtilis, where five endophytic fungi were obtained and assigned to Penicillium chrysogenum and Penicillium crustosum. The isolated endophytes differentially produced indole acetic acid (IAA) and ammonia, and in addition to their enzymatic and antimicrobial activities, they exhibited variable capacity for phosphate solubilization. In order to investigate the effect of endophytes on plant growth, four representative endophytes and their consortiums were selected concerning to their potential ability to promote plant growth. The results indicated that microbial endophytes isolated from medicinal plants possessing a vital role to improve plant growth and could be used as inoculants to establish a sustainable crop production system.
Industrial wastewater treatment is one of the greatest challenges of humanity that require an increased awareness to address water scarcity worldwide. Herein, an eco-friendly and cost-effective ...approach was established to cope with real textile and tannery effluents via the biosynthesis of highly adsorbent magnesium oxide nanoparticles (MgO-NPs). Physicochemical characterization of as-formed MgO-NPs confirms the successful fabrication of MgO nano-rods (30–85 nm) and nano-rectangular (18.6–27.6 nm) by harnessing metabolites secreted by Aspergillus niger strain F1. Moreover, the energy dispersive spectroscopy (EDX) confirms that Mg and O are the main components in the sample with weight percentages of 41.1% and 33.6%, respectively. X-ray photoelectron spectroscopy (XPS) confirms the successful formation of MgO at different bending energies. The catalytic degradation and decolorization analyses were conducted under sunlight and dark conditions. These analyses demonstrated that the highest decolorization of real textile and tannery effluents (92.8% ± 0.06% and 97.5% ± 0.7%, respectively) was accomplished after 180 min by treatment with 1.0 mg mL−1 of MgO-NPs in the presence of sunlight. At optimum experimental conditions, the quality of treated effluents was monitored by the reduction of total suspended solid (TSS), total dissolved solid (TDS), and chemical oxygen demand (COD) levels at the percentages of 86.9% ± 0.8%, 77.0% ± 0.8%, and 89.3% ± 0.9%, respectively, for textile effluent and the percentages of 94.3% ± 1.6%, 80.7% ± 1.6%, and 97.4% ± 0.9% respectively, for tannery effluent. The reusability of MgO-NPs showed its activity for textile effluents treatment for four cycles. Biosynthesized MgO-NPs showed a high adsorption capacity for predominant tannery heavy metals, namely, Cr, Co, Pb, Cd, and Ni having removal percentages of 94.2% ± 1.2%, 63.4% ± 1.7%, 72.7% ± 1.3%, 74.1% ± 1.8%, and 70.8% ± 1.5%, respectively. The toxicity of treated effluents was assessed by the germination of corn and broad bean seeds, which exhibited a decreased toxicity as compared with untreated effluents. Interestingly, the biosynthesized MgO-NPs exhibit antimicrobial activity against different pathogenic microbes and their activities were dose-dependent.
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•Nano-MgO with varied shapes was successfully green synthesized by Aspergillus niger.•Textile and tannery effluents treatment and antimicrobial activity of MgO-NPs were investigated.•The decolorization percentages were higher under sunlight stimulator than dark ambient.•Biosynthesized MgO-NPs showed high adsorption efficacy for tannery effluent heavy metals.•The toxicity of treated/untreated effluents was assessed using seed germination.
In this study, two endophytic actinomycetes isolates Oc-5 and Acv-11, were isolated from healthy leaves of medicinal plant
Oxalis corniculata L
. These isolates were identified as
Streptomyces ...zaomyceticus
Oc-5 and
Streptomyces pseudogriseolus
Acv-11 using 16S rRNA gene sequence. Biomass extract of these strains were used as a greener attempt for synthesis of copper oxide nanoparticles (CuO-NPs). The synthesized NPs were characterized by UV–Vis spectroscopy, Fourier transform infra-red (FT-IR) spectroscopy, X-ray diffraction (XRD)‚ transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS). Green synthesized NPs showed surface plasmon resonance (SPR) absorption band at 400 nm, crystalline nature, spherical-shaped with an average size of 78 nm and 80.0 nm for CuO-NPs synthesized using strain Oc-5 and Acv-11, respectively. The bioactivities of CuO-NPs were evaluated. Results revealed that CuO-NPs exhibited promising antimicrobial activity against prokaryotic and eukaryotic microbial cells (Gram positive bacteria, Gram negative bacteria, unicellular and multicellular fungi). In addition, it showed antimicrobial potential against phyto-pathogenic fungal strains
Fusarium oxysporum, Pythium ultimum, Aspergillus niger
and
Alternaria alternata.
We further explored the in vitro antioxidant activity and cytotoxicity for biosynthesized CuO-NPs. The results revealed that‚ scavenging and total antioxidant activity for NPs synthesized using
Streptomyces pseudogriseolus
Acv-11 was better than those synthesized by
Streptomyces zaomyceticus
Oc-5. Also, the morphological changes and cell viability for Vero and Caco-2 cell line due to NPs treatments were assessed using MTT assay method. Furthermore, Larvicidal efficacy against
Musca domestica
and
Culex pipiens
was evaluated. The results obtained in this study clearly showed that biosynthesized CuO-NPs exhibited effective bioactivity and, therefore, provide a base for the development of versatile biotechnological applications soon.
In this study, metabolites involved in the free-biomass filtrates for three endophytic actinomycetes of
Streptomyces capillispiralis
Ca-1,
Streptomyces zaomyceticus
Oc-5, and
Streptomyces ...pseudogriseolus
Acv-11 were used as biocatalysts for green synthesis of silver nanoparticles (Ag-NPs). Characterization of biosynthesized Ag-NPs was accomplished using UV-Vis spectroscopy, X-ray diffraction patterns (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM-EDX), transmission electron microscopy (TEM), and particle size analyzer. The biosynthesized Ag-NPs showed maximum surface plasmon resonance (SPR) at 440 for strain Ca-1 and 450 for both strains of OC-5 and Acv-11. Nanoparticle spherical shape was recorded with size ranging from 23.77 to 63.14 nm, 11.32 to 36.72 nm, and 11.70 to 44.73 nm for Ca-1, Oc-5, and Acv-11, respectively. SEM-EDX analysis exhibited the weight percentages of 17.3, 22.3, and 48.7% for Ag-NPs synthesized by strains Ca-1, Oc-5 and Acv-11, respectively. The activities of biosynthesized Ag-NPs were concentration dependent and the obtained results confirmed the efficacy of Ag-NPs as antimicrobial agents against Gram-positive and Gram-negative bacteria as well unicellular and multicellular fungi. The MIC for Gram-positive bacteria, Gram-negative bacteria (
E. coli
), and eukaryotic microorganisms was 0.25 mM with clear zone ranging from 10.3 to 14.6 mm, while MIC for
Pseudomonas aeruginosa
was 1.0 mM for Ag-NPs synthesized by strain Ca-1 and 0.25 mM for those synthesized by strains Oc-5 and Acv-11. Moreover, Ag-NPs exhibited antimicrobial activity against four plant pathogenic fungi represented by
Alternaria alternata
,
Fusarium oxysporum
,
Pythium ultimum
, and
Aspergillus niger
at 2.0, 1.5, 1.0, and 0.5 mM of Ag-NPs with different degree. In vitro assessment of the antioxidant efficacy of biosynthesized Ag-NPs was achieved by scavenging assay of H
2
O
2
, reducing power of Fe
3+
, or total antioxidant assay. The results showed that antioxidant activities of Ag-NPs were concentration dependent with the highest activity at Ag-NP concentration of 2.0 mM. Furthermore, the biosynthesized NPs have prospective bioinsecticidal activity against
Culex pipiens
and
Musca domestica.
Green synthesis of NPs could be quite potential for the development of new bioactive compounds used in different biomedical applications.
Nowadays, medical textiles have become the most essential and developing part in human healthcare sector. This work was undertaken with a view to harness the bio-active macromolecules secreted by ...fungi e.g. proteins and enzymes in bio-synthesis of ZnO nanoparticles for multifunctional textiles such as antibacterial activity and UV protection with considering the cytotoxicity limitation. Herein, the isolated fungus, Aspergillus terreus, was allowed to produce proteins which has affinity to cape ZnO-NPs. Various factors affecting the behavior of the secreted proteins on the formed nanoparticles were investigated. Thorough characterizations of the protein capped ZnO-NPs were performed by the using of UV–Visible spectroscopy, transmission electron microscope (TEM) Fourier Transform-Infra Red (FT-IR) spectroscopy, X-ray diffraction (XRD) analysis and Dynamic light scattering analysis (DLS). Prior treatment of cotton fabrics with ZnO-NPs, the cytotoxicity of the protein capped ZnO-NPs was examined. After that, the antibacterial activity of the ZnO-NPs before and after treating of cotton fabrics, besides, the UV-protection (UPF) properties were investigated. Results obviously demonstrated the ability of the bio-secreted protein to cape and reduce ZnO to spherical ZnO-NPs with particle size lied around 10–45 nm, as indicated form UV–vis., spectra TEM, Zeta sizer, FTIR and XRD. Regarding to the results of cytotoxicity, the treatment of the cotton fabrics with ZnO-NPs were performed at safe dose (20 ppm). At this dose, ZnO-NPs loaded samples exhibited reasonable antibacterial activity against both Gram positive and Gram negative bacteria; besides, good UV-protection with reasonable increase in UVA and UVB blocking values. Indeed, nanotechnology based microbiological active molecules opens up new opportunities for us to explore novel applications in terms of green technology.
•Spherical narrow-sized ZnO-NPs were prepared using fungus Aspergillus terreus.•Optimization of the biosynthesized ZnO-NPs was performed.•Cytotoxicity dose of ZnO-NPs prior application was studied.•Antibacterial activity and UV-protection of the treated cotton fabrics were investigated at safe ZnO-NPs dose.
An endophytic strain of Streptomyces antimycoticus L-1 was isolated from healthy medicinal plant leaves of Mentha longifolia L. and used for the green synthesis of silver nanoparticles (Ag-NPs), ...through the use of secreted enzymes and proteins. UV–vis spectroscopy, Fourier-transform infrared (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and dynamic light scattering (DLS) analyses of the Ag-NPs were carried out. The XRD, TEM, and FT-IR analysis results demonstrated the successful biosynthesis of crystalline, spherical Ag-NPs with a particle size of 13–40 nm. Further, the stability of the Ag-NPs was assessed by detecting the surface Plasmon resonance (SPR) at 415 nm for one month or by measuring the NPs surface charge (−19.2 mV) by zeta potential analysis (ζ). The green-synthesized Ag-NPs exhibited broad-spectrum antibacterial activity at different concentrations (6.25–100 ppm) against the pathogens Staphylococcus aureus, Bacillus subtilis Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhimurium with a clear inhibition zone ranging from (9.5 ± 0.4) nm to (21.7 ± 1.0) mm. Furthermore, the green-synthesized Ag-NPs displayed high efficacy against the Caco-2 cancerous cell line (the half maximal inhibitory concentration (IC50) = 5.7 ± 0.2 ppm). With respect to antibacterial and in-vitro cytotoxicity analyses, the Ag-NPs concentration of 100 ppm was selected as a safe dose for loading onto cotton fabrics. The scanning electron microscopy connected with energy-dispersive X-ray spectroscopy (SEM-EDX) for the nano-finished fabrics showed the distribution of Ag-NPs as 2% of the total fabric elements. Moreover, the nano-finished fabrics exhibited more activity against pathogenic Gram-positive and Gram-negative bacteria, even after 10 washing cycles, indicating the stability of the treated fabrics.
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•For the first time, γ-Fe2O3-NPs was bio-fabricated using Penicillium expansum.•Characterization of γ-Fe2O3-NPs was accomplished by FT-IR, XRD, TEM, DLS, and XPS.•γ-Fe2O3-NPs exhibit ...high efficacy in crude textile effluent treatment with 89 % dye removal.•NPs exhibit removal % of 86.8, 71.8, and 89.3 for COD, TDS, and TSS, respectively.•γ-Fe2O3-NPs treated tannery effluent showed high efficacy for heavy metals removal.
Wastewater treatment is one of the vital solutions to the global water shortage and many related environmental problems. The present study aimed at biosynthesizing maghemite nanoparticles (γ-Fe2O3-NPs) using Penicillium expansum (K-w) for the purpose of wastewater treatment. The γ-Fe2O3-NPs resultant was characterized using fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM), dynamic light scattering (DLS), and X-ray photoelectron spectroscopy (XPS). The maghemite nanoparticles capacity to mediate decolorization and degradation of textile and tanning wastewater effluents was investigated. Results verified that the successful synthesis of spherical shaped Fe2O3-NPs of 15.0–66.0 nm size, with XRD peaks that match the cubic structure of the γ-Fe2O3. XPS analysis confirmed the presence of iron as Fe2O3. Decolorization and degradation analyses indicated that γ-Fe2O3-NPs are effective biocatalysts for dye degradation under dose- and time-dependent manner. The highest decolorization gain (89 %–90 %) occurred after 6.0–8.0 h of incubation at 1.0 mg mL-1 of γ-Fe2O3-NPs. Quality of the treated textile wastewater was improved, as indicated by the reduction in chemical oxygen demand (COD), total dissolved solids (TDS), and total suspended solids (TSS) by 86.8, 71.8, and 89.3 %, respectively. GC–MS results showed the complete disappearance or reduction of peaks, or peak areas in treated textile wastewater in comparison with the untreated samples. In addition, treatment of tanning wastewater with γ-Fe2O3-NPs has also resulted in decolorization, as well as reduction in COD, TDS, and TSS levels by 93.1, 40.5, and 95.9 %, respectively. The treated tanning wastewater showed low heavy metal levels, with removal percentages ranging from 66 %–98 % for Co, Cr, Pb, Ni, and Cd, indicating the high efficiency of γ-Fe2O3-NPs in improving treated wastewater quality.
Salinity is a major problem affecting crop production all over the world. A wide range of adaptation strategies are required to overcome this problem. Endophytic bacteria can build a symbiotic ...association with their host to improve host plant salt tolerance. In this study, eighteen bacterial endophyte strains were isolated from two native halophytic plants
Arthrocnemum macrostachyum
and
Spergularia marina,
and identified as
Bacillus
,
Brevibacillus
,
Agrobacterium
, and
Paenibacillus
. These endophytic strains exhibit plant growth-promoting activities including phosphate solubilizing, ammonia production, biocontrol of phytopathogen, extracellular enzymatic activities, and indole-3-acetic acid production under normal and salinity stress. A pot experiment was conducted under field conditions to alleviate the harmful effects of soil salinity on bean (
Vicia faba
L.) by inoculating their seeds with the most potent bacterial isolates
Bacillus subtilis
(AR5) and
Bacillus thuringiensis
(BR1). Salinity treatments induced a significant decrease in both growth parameters and metabolic activities, while the activity of antioxidant enzymes and proline content was significantly increased. However, salinity stress induced higher contents of Na
+
and decreased contents of N
+
, P
3+
, K
+
, Ca
2+
, Mg
2+
, and K
+
:Na
+
, it was found that treatment with
B. subtilis
(AR5) and
B. thuringiensis
(BR1) individually or in a combination mitigated the effect of salt stress and improved the plant height, shoot dry weights, proline contents, enzymes activities as well enhanced the accumulation of mineral nutrients in shoot plants. Our results concluded that treatment with co-inoculation of
B. subtilis
(AR5) and
B. thuringiensis
(BR1) exerted the greatest effect in alleviating the harmful effect of soil salinity stress and can be used as a suitable bio-approach to reclaim salinity-stressed soils.
The discovery of eco-friendly, rapid, and cost-effective compounds to control diseases caused by microbes and insects are the main challenges. Herein, the magnesium oxide nanoparticles (MgO-NPs) are ...successfully fabricated by harnessing the metabolites secreted by
. The fabricated MgO-NPs were characterized using UV-Vis, XRD, TEM, DLS, EDX, FT-IR, and XPS analyses. Data showed the successful formation of crystallographic, spherical, well-dispersed MgO-NPs with sizes of 7-40 nm at a maximum wavelength of 250 nm. The EDX analysis confirms the presence of Mg and O ions as the main components with weight percentages of 13.62% and 7.76%, respectively. The activity of MgO-NPs as an antimicrobial agent was investigated against pathogens
,
,
,
, and
, and exhibited zone of inhibitions of 12.0 ± 0.0, 12.7 ± 0.9, 23.3 ± 0.8, 17.7 ± 1.6, and 14.7 ± 0.6 mm respectively, at 200 µg mL
. The activity is decreased by decreasing the MgO-NPs concentration. The biogenic MgO-NPs exhibit high efficacy against different larvae instar and pupa of
, with LC50 values of 12.5-15.5 ppm for I-IV larvae instar and 16.5 ppm for the pupa. Additionally, 5 mg/cm
of MgO-NPs showed the highest protection percentages against adults of
, with values of 100% for 150 min and 67.6% ± 1.4% for 210 min.