Green synthesis of Superparamagnetic Iron Oxide and Silver Nanoparticles in Satureja hortensis Leave Extract: Evaluation of Antifungal Effects on Botryosphaeriaceae Species

In recent years, green synthesis methods of metallic nanoparticles (MNPs) have been attractive because of the more facile, cheaper, and appropriate features associated with biomolecules in MNPs biosynthesis. This research represented an easy, fast, and environmentally friendly method to biosynthesis of superparamagnetic iron oxide nanoparticles (SPIONPs) and silver nanoparticles (AgNPs) by the Satureja hortensis leaf extract as stabilizer and reducer. The SPIONPs synthesized in co-precipitation method. The biosynthesized SPIONPs and AgNPs were studied their antifungal effects against three Botryosphaeriaceae plant pathogens, Botryosphaeria dothidea, Diplodia seriata, and Neofusicoccum parvum. UV-visible spectra (UV-Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), field emission scanning electron microscopy (Fe-SEM), energy-dispersive X-ray spectroscopy (EDX), and vibrating-sample magnetometer (VSM) analyses were used to evaluate the physicochemical properties and verify the formation of green synthesized SPIONPs and AgNPs. UV-Vis spectra revealed absorption peaks at 243 and 448 nm for SPIONs and 436 nm for AgNPs, respectively. Microscopic and XRD analysis showed that SPIONPs and AgNPs was found spherical in shape with an average particle size of SPIONPs and AgNPs 10 and 12 nm, respectively. The antifungal test against Botryosphaeriaceae species showed that SPIONPs and AgNPs possess antifungal properties against B. dothidea, D. seriata, and N. parvum. However, AgNPs exhibits greater antifungal activity than SPIONPs. The results of the cytotoxicity tests of SPIONs and AgNPs on the MCF-7 cell line showed that AgNPs was significantly more cytotoxic towards the MCF-7 cell line, whereas no significant cytotoxic effect was recorded by SPIONs. Therefore, these biosynthesized MNPs could be substituted for toxic fungicides that are extensively applied in agriculture and contribute to environmental health and food safety.

Porous α-Fe2O3 nanocarriers: Biosynthesis and in vitro gene delivery applications

Non-viral gene delivery is a new therapeutic in the treating genetic disorders. The most important challenge in nonviral gene transformation is the immunogenicity of carriers. Nowadays, The immunogenicity of nanocarriers as a deliverer of nucleic acid molecules has received significant attention. In this research, hematite green nanocarriers were prepared in one step with rosemary extract. Synthetic nanocarriers were investigated by using XRD (X-ray diffraction analysis), FESEM-EDX (field emission scanning electron microscopy with energy dispersive X-Ray spectroscopy), HR-TEM (high-resolution transmission electron microscopy), VSM (value stream mapping), TGA- DTG (thermal gravimetric analysis-differential thermal analysis), FT-IR (fourier-transform infrared spectroscopy), BET (brunauer-emmett-teller) and BJH (barrett-joyner-halenda) analyses. The cytotoxicity of synthetic nanocarriers was evaluated on HEK-293Tcell lines at concentration of 1-500 μg/ml using MTT method. Finally, targeted transfection of GFP plasmid using green porous particles was performed using an external magnetic field. Biogenic hematite nanoparticles with hexagonal crystal structures have a 3D pile flower-like morphology. The existence of rosemary phytochemicals in the construction of nanoparticles has caused minimal toxicity and high biocompatibility of nanocarriers. Also, TGA studies confirmed the stability of bionic nanoparticles. Superparamagnetic green nanocarriers at concentrations above 500 μg/ml is not toxic to HEK293T cells. The delivery efficiency of the plasmid was optimal at an N/P ratio of 3. Therefore, the porous α-Fe2O3 green nanocarriers are non-viral and safe carriers with potential applications in gene therapy.

Synthesis of magnetic nanoparticles and their effects on growth and physiological parameters of Calotropis procera seedlings

The present study was carried out to elucidate effects of synthesized magnetic nanoparticles (MNPs) on morphological and physiological parameters and main essential oil components of Calotropis procera seedlings. For this purpose, 21-day-old seedlings grown under hydroponic conditions were treated by the different MNP concentrations (0, 50, 100, 150, and 200 mg L^-1). The results showed that the growth parameters, chlorophyll pigments, soluble sugars, and total proteins significantly increased in leaf under MNP treatment, except for the root length. As compared to the control, MNPs induced a substantial change in the activities of antioxidant enzymes, H₂O₂, and malondialdehyde contents. Ascorbate peroxidase activity showed a meaningful increase in leaf treated with 200 mg L^-1 MNPs, while superoxide dismutase activity and concentration of H₂O₂ conspicuously decreased relative to the control. Moreover, MNPs enhanced geranial, 1,8-cineol, a-phellandrene, citronellal, camphor, and terpinen-4-ol contents as major components. These results suggest that MNPs could be a promising method of iron application in agricultural systems. Regarding the effects of MNPs, 200-mg L^-1 MNPs were most effective on the production of main essential oils and plant growth that could serve as a favorable elicitor for plant improvement.

Partial cloning, characterization, and analysis of expression and activity of plasma membrane H+-ATPase in Kallar grass [Leptochloa fusca (L.) Kunth] under salt stress

Kallar grass (Leptochloa fusca) is a highly salt-tolerant C4 perennial halophytic forage. The regulation of ion movement across the plasma membrane (PM) to improve salinity tolerance of plant is thought to be accomplished with the aid of the proton electrochemical gradient generated by PM H⁺-ATPase. In this study, we cloned a partial gene sequence of the Lf PM H⁺-ATPase and investigated its expression and activity under salt stress. The amino acid sequence of the isolated region of Lf PM H⁺-ATPase possesses the maximum identity up to 96% to its ortholog in Aeluropus littoralis. The isolated fragment of Lf PM H⁺-ATPase gene is a member of the subfamily Π of plant PM H⁺-ATPase and is most closely related to the Oryza sativa gene OSA7. The transcript level and activity of the PM H⁺-ATPase were increased in roots and shoots in response to NaCl and were peaked at 450 mM NaCl in both tissues. The induction of activity and gene expression of PM H⁺-ATPase in roots and shoots of Kallar grass under salinity indicate the necessity for this pump in these organs during salinity adaptation to establish and maintain the electrochemical gradient across the PM of the cells for adjusting ion homeostasis.

Biosynthesis of spinel nickel ferrite nanowhiskers and their biomedical applications

Greener methods for the synthesis of various nanostructures with well-organized characteristics and biomedical applicability have demonstrated several advantages, including simplicity, low toxicity, cost-effectiveness, and eco-friendliness. Spinel nickel ferrite (NiFe2O4) nanowhiskers with rod-like structures were synthesized using a simple and green method; these nanostructures were evaluated by X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, and X-ray energy diffraction spectroscopy. Additionally, the prepared nanowhiskers could significantly reduce the survival of Leishmania major promastigotes, at a concentration of 500 μg/mL; the survival of promastigotes was reduced to ≃ 26%. According to the results obtained from MTT test (in vitro), it can be proposed that further studies should be conducted to evaluate anti-leishmaniasis activity of these types of nanowhiskers in animal models.

Bimetallic nickel-ferrite nanorod particles: greener synthesis using rosemary and its biomedical efficiency

Nickel-ferrite (NiFe₂O₄) nanorods particles (NRP) was biosynthesised for the first time by the Rosemary Extract. The NRP was fully characterised, including the type, nanostructure and physicochemical properties of using XRD, HRTEM, FeSEM, XPS, FTIR and VSM. TEM confirmed rod-shaped nano-sized particles with average sizes ranging from 10 nm to 28 nm. The EDAX Analysis showed the presence of iron, nickel, oxygen, and carbon. XRD analysis confirmed the synthesis of NiFe₂O₄ crystals. XPS curves showed photoelectron for iron, oxygen and nickel. EDS showed the atomic, weight percentages ratios of Ni(12%): Fe(24%) and: O(48) are close to the theoretical value (Ni: Fe:O = 1:2:4), of bimetallic magnetic NiFe₂O₄ NRP. NiFe₂O₄ NRP had cytotoxicity effect on MCF-7 cells survival which suggests that NiFe₂O₄ NRP can be used as a new class of anticancer agent in design novel cancer therapy research.

Dual catalytic DNA circuit-induced gold nanoparticle aggregation: An enzyme-free and colorimetric strategy for amplified detection of nucleic acids

An enzyme-free dual catalytic DNA circuit for amplified detection of nucleic acids has been developed. The system functions based on a cyclic self-assembly of two auxiliary hairpins (H1 and H2) and three biotinylated hairpin oligonucleotides (H3, H4 and H5), in the format of two molecular circuits. In the upstream circuit, a target initiator (I) besides H1 and H2 hairpins constructs H1-H2 duplexes that trigger the operation of a subsequent circuit. In the downstream circuit, the H1-H2 duplex initiates cascaded self-assembly reactions, produces triplex H3-H4-H5, as sensing system, and releases the H1-H2 duplex as the catalyst for the self-assembly of additional hairpins. The H3-H4-H5 triplex acts as the scaffolds for assembling and orienting the streptavidin-functionalized gold nanoparticles (SA-AuNPs) into a lattice-like arrangement that generates a DNA-SA-AuNP cross-linked network, resulting in a dramatic pale red-to-blue color change. By ingeniously engaging two catalytic circuits with feedback amplification capabilities, the system can detect the target nucleic acid with an LOD value of 5 femtomolar and unambiguously discriminate spurious targets (i.e. targets containing substitution, insertion, and deletion nucleotides) without instrumentation. Simple and convenient operation of the assay makes the DNA circuit appropriate for point-of-care monitoring in resource-constrained settings.

Investigation of ZnO nanoparticles on proline, anthocyanin contents and photosynthetic pigments and lipid peroxidation in the soybean

The interaction between nanoparticles and plants is inevitable. In this study, the effect of different concentrations of ZnO nanoparticles synthesised using olive extract on the soybean was studied. The soybean seeds were cultured in a Hoagland medium containing agar which was treated different concentrations (0, 200 and 400 ppm) of ZnO nanoparticles. After 21 days, the plants were harvested and the parameters of proline, anthocyanin, malondialdehyde (MDA), hydrogen peroxide (H2O2), chlorophyll and carotenoid contents and phenylalanine ammonia-lyase (PAL) and catalase (CAT) activity in soybeans (Glycine max) were measured. The results showed that the levels of chlorophyll a and b and carotenoid at concentrations of 200 and 400 ppm in comparison with control decreased, while carotenoid content at 200 ppm concentration at a concentration of 400 ppm was not significant. The level of anthocyanin and PAL activity increased with increasing concentration of nanoparticles, while proline content decreased. By increasing the concentration of ZnO nanoparticles, the content of MDA and hydrogen peroxide increased compared to control but CAT activity did not change significantly. This research suggests that ZnO nanoparticles synthesised using olive extract in soybean plants may be toxic by reactive oxygen species production.

Leishmanicidal Activity of Biogenic Fe₃O₄ Nanoparticles

Abstract: Due to the multiplicity of useful applications of metal oxide nanoparticles (ONPs) in medicine are growing exponentially, in this study, Fe₃O₄ (iron oxide) nanoparticles (IONPs) were biosynthesized using Rosemary to evaluate the leishmanicidal efficiency of green synthesized IONPs. This is the first report of the leishmanicidal efficiency of green synthesized IONPs against Leishmania major. The resulting biosynthesized IONPs were characterized by ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR). The leishmanicidal activity of IONPS was studied via 3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results showed the fabrication of the spherical shape of monodisperse IONPs with a size 4 ± 2 nm. The UV-visible spectrophotometer absorption peak was at 334 nm. The leishmanicidal activity of biogenic iron oxide nanoparticles against Leishmania major (promastigote) was also studied. The IC₅₀ of IONPs was 350 µg/mL. In this report, IONPs were synthesized via a green method. IONPs are mainly spherical and homogeneous, with an average size of about 4 nm, and were synthesized here using an eco-friendly, simple, and inexpensive method.

Green synthesis of ZnO nanoparticles by Olive (Olea europaea)

Green synthesis of nanoparticles is superior to physical and chemical methods as it is environment-friendly and cost-effective. The present study was carried out for inducing nanoparticles synthesis by zinc nitrate in the leaves extracts of olive. Further leaves extracts were evaluated for antiradical scavenging activity by 1, 1-diphenyl-2-picryl-hydrazyl assay. Morphological and structural properties of the synthesised ZnO nanoparticles have been characterised using UV-Vis spectrophotometer, FTIR, TEM, XRD and dynamic light scattering (DLS) analysis. Further, zinc oxide nanoparticles were evaluated for antiradical scavenging activity by capacity of total antioxidant assay. Synthesised ZnO nanoparticles were confirmed by the absorption maxima at the wavelength of 370 nm. TEM image revealed that ZnO nanoparticles were spherical with average size 41 nm. FTIR investigation suggested that the flavonoids, glycosides, proteins and phenols molecules can play an important role in the stabilisation of ZnO nanoparticles.

Extract-mediated synthesis of Ag@AgCl nanoparticles using Conium maculatum seeds: characterization, antibacterial activity and cytotoxicity effect against MCF-7 cell line

Silver/silver chloride nanoparticles synthesized using the seed extract of Conium maculatum exhibited considerable antimicrobial activity and cytotoxicity against MCF-7 cell line.

Phoenix dactylifera (date palm) pit aqueous extract mediated novel route for synthesis high stable silver nanoparticles with high antifungal and antibacterial activity

The biological synthesis of silver nanoparticles (AgNPs) was conducted using date palm pit aqueous extract. The first visible sign of the synthesis of AgNPs was the change in colour of reaction mixtures from yellowish to reddish brown. The resulting synthesised AgNPs were characterised using UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The UV-visible spectra gave surface plasmon resonance at 428 nm. XRD confirmed that the silver particles formed in our experiments were in the form of nanocrystals. TEM images revealed the formation of AgNPs with spherical shape and sizes in the range between 1-40 nm. DLS showed nanoparticles with an average size of 27 nm. Fourier transform infrared spectroscopy indicated the role of different possible functional groups (carboxyl, amine, aromatic and hydroxyl) in the formation of AgNPs. AgNPs were stable at 28°C in vitro for over a year without any precipitation or decreased production of antimicrobial effect. Then, the antifungal and antibacterial activities of synthesised AgNPs were investigated. The synthesised AgNPs showed significant inhibitory effects on Rhizoctonia solani (AG2_2) cultures, so that the concentration of 25 µg/ml prevented approximately 83% of the mycelium growth of the fungus. Then, the broth macro-dilution method was used for examining antibacterial effect of AgNPs. The minimum inhibitory concentration and minimum bactericide concentration against Klebsiella pneumonia (PCI 602) and Acinetobacter baumannii (ATCC 19606) were recorded as 1.56 and 3.12 µg/ml AgNPs, respectively.