Effects of magnetite nanoparticles on physiological processes to alleviate salinity induced oxidative damage in wheat.

BACKGROUND: One of the major abiotic stressors that have a serious effect on plant growth and productivity worldwide is the salinity of soil or irrigation water. The effect of foliar application of magnetite nanoparticles (size = 22.05 nm) at different concentrations (0, 0.25, 0.5, and 1.0 ppm) was investigated to improve salinity tolerance in two wheat cultivars, namely, Misr1 (Tolerant) and Gimmeza11 (Sensitive). Moreover, toxicological investigations of magnetite oxide nanoparticle in Wistar albino rats were estimated. RESULTS: The magnetite nanoparticles positively affected growth, chlorophyll, and enzymatic antioxidants such as superoxide dismutase (SOD), stimulating reduced glutathione and improving the aggregation of several polypeptide chains that may be linked to the tolerance of saline stress. In contrast, magnetite nanoparticles reduced malondialdehyde (MDA). Inverse sequence-tagged repeat (ISTR) assay of DNA molecular marker showed the change in band numbers with the highest polymorphic bands with 90% polymorphism at primer F3, B5 and 20 positive bands in Gimmeza11 with 0.5 ppm magnetite nanoparticles. In the median lethal dose (LD50 ) study, no rats died after the oral administration of magnetite nanoparticle at different doses. Therefore, the iron oxide nanoparticle was nontoxic when administered orally by gavage. CONCLUSION: Magnetite nanoparticles partially helped to alleviate the effects of salt stress by activating growth, chlorophyll content, SOD, glutathione, and soluble proteins in two wheat cultivars (Misr1 and Gimmeza11) and decreasing MDA content. © 2021 Society of Chemical Industry.

Green synthesis, characterization, and hepatoprotective effect of zinc oxide nanoparticles from Moringa oleifera leaves in CCl4-treated albino rats.

Hepatotoxin carbon tetrachloride (CCl4) causes liver injury. This research aims to create ZnO-NPs using green synthesis from Moringa oleifera (MO) leaves aqueous extract, and chemically prepared and confirming the synthesis by specialized equipment analysis. The sizes formed of ZnO-NPs were 80 and 55 nm for chemical and green methods, respectively. In addition, to study their ability to protect Wistar Albino male rats against oxidative stress exposed to carbon tetrachloride. MO leaf aqueous extract, green synthesized ZnO-NPs, and ZnO-NPs prepared chemically at 100 and 200 mg/kg BW per day were investigated for their hepatoprotective effects on liver enzyme biomarkers, renal biomarkers, antioxidant enzymes, lipid peroxidation, hematological parameters, and histopathological changes. Compared to the control group, all liver and kidney indicators were considerably elevated after the CCl4 injection. However, the activity of antioxidant enzymes in the liver was significantly reduced after the CCl4 injection. These outcomes indicate that MO leaf aqueous extract, greenly synthesized ZnO-NPs, and ZnO-NPs chemically prepared can restore normal liver and kidney function and activity, as well as hematological and antioxidant enzymes. The highest impact on enhancing the hepatoprotective effect was recorded for rats that received green synthesized ZnO-NPs. The increased drug delivery mechanism of green synthesized ZnO-NPs resulted in a higher protective effect than that of MO leaf aqueous extract.

Biosynthesis of zinc oxide nanoparticles via neem extract and their anticancer and antibacterial activities.

In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized using neem leaf aqueous extracts and characterized using transmission electron microscopy (TEM), ultraviolet visible spectroscopy (UV-Vis), and dynamic light scattering (DLS). Then compare its efficacy as anticancer and antibacterial agents with chemically synthesized ZnO-NPs and the neem leaf extract used for the green synthesis of ZnO-NPs. The TEM, UV-vis, and particle size confirmed that the developed ZnO-NPs are nanoscale. The chemically and greenly synthesized ZnO-NPs showed their optical absorbance at 328 nm and 380 nm, respectively, and were observed as spherical particles with a size of about 85 nm and 62.5 nm, respectively. HPLC and GC-MS were utilized to identify the bioactive components in the neem leaf aqueous extract employed for the eco-friendly production of ZnO-NPs. The HPLC analysis revealed that the aqueous extract of neem leaf contains 19 phenolic component fractions. The GC-MS analysis revealed the existence of 21 bioactive compounds. The antiproliferative effect of green ZnO-NPs was observed at different concentrations (31.25 µg/mL-1000 µg/mL) on Hct 116 and A 549 cancer cells, with an IC50 value of 111 µg/mL for A 549 and 118 µg/mL for Hct 116. On the other hand, the antibacterial activity against gram-positive and gram-negative bacteria was estimated. The antibacterial result showed that the MIC of green synthesized ZnO-NPs against gram-positive and gram-negative bacteria were 5, and 1 µg/mL. Hence, they could be utilized as effective antibacterial and antiproliferative agents.

Antifungal Activity of Green and Chemically Synthesized ZnO Nanoparticles against Alternaria citri, the Causal Agent Citrus Black Rot.

Citrus black rot is a serious disease of citrus plants caused by Alternaria citri. The current study aimed to synthesize zinc oxide nanoparticles (ZnO-NPs) by chemically or green method and investigate their antifungal activity against A. citri. The sizes of synthesized as measured by transmission electron microscope of ZnO-NPs were 88 and 65 nm for chemical and green methods, respectively. The studied prepared ZnO-NPs were applied, in vitro and in situ, at different concentrations (500, 1,000, and 2,000 µg/ml) in post-harvest treatment on navel orange fruits to verify the possible control effect against A. citri. Results of in vitro assay demonstrated that, at concentration 2,000 µg/ml, the green ZnO-NPs was able to inhibit about 61% of the fungal growth followed by 52% of chemical ZnO-NPs. In addition, scanning electron microscopy of A. citri treated in vitro with green ZnO-NPs showed swelling and deformation of conidia. Results showed also that, using a chemically and green ZnO-NPs at 2,000 µg/ml in situ in post-harvest treatment of orange, artificially-infected with A. citri, has reduced the disease severity to 6.92% and 9.23%, respectively, compared to 23.84% of positive control (non-treated fruits) after 20 days of storage. The out findings of this study may contribute to the development of a natural, effective, and eco-friendly strategy for eradicating harmful phytopathogenic fungi.

Chitosan neem nanocapsule enhances immunity and disease resistance in nile tilapia (Oreochromis niloticus).

Finding eco-friendly alternatives for antibiotics in treating bacterial diseases affecting the aquaculture sector is essential. Herbal plants are promising alternatives, especially when combined with nanomaterials. Neem (Azadirachta indica) leaves extract was synthesized using a chitosan nanocapsule. Chitosan neem nanocapsule (CNNC) was tested in-vitro and in-vivo against the Aeromonas sobria (A. sobria) challenge in Nile tilapia. A preliminary experiment with 120 Nile tilapia was conducted to determine the therapeutic dose of CNNC, which was established to be 1 mg/L. A treatment study was applied for seven days using 200 fish categorized into four groups (10 fish/replicate: 50 fish/group). The first (control) and second (CNNC) groups were treated with 0 and 1 mg/L CNNC in water without being challenged. The third (A. sobria) and fourth (CNNC + A. sobria) groups were treated with 0 and 1 mg/L CNNC, respectively, and challenged with A. sobria (1 × 107 CFU/mL). Interestingly, CNNC had an in-vitro antibacterial activity against A. sobria; the minimum inhibitory concentration and minimum bactericidal concentration of CNNC against A. sobria were 6.25 and 12.5 mg/mL, respectively. A. sobria challenge caused behavioral alterations, skin hemorrhage, fin rot, and reduced survivability (60%). The infected fish suffered a noticeable elevation in the malondialdehyde level and hepato-renal function markers (aspartate aminotransferase, alanine aminotransferase, and creatinine). Moreover, a clear depletion in the level of the antioxidant and immune indicators (catalase, reduced glutathione, lysozymes, nitric oxide, and complement 3) was obvious in the A. sobria group. Treatment of the A. sobria-challenged fish with 1 mg/L CNNC recovered these parameters and enhanced fish survivability. Overall, CNNC can be used as a new versatile tool at 1 mg/L as a water treatment for combating the A. sobria challenge for sustainable aquaculture production.