Role Of Zinc Oxide Nanoparticles Research Articles

Alleviated cadmium toxicity in wheat (Triticum aestivum L.) by the coactive role of zinc oxide nanoparticles and plant growth promoting rhizobacteria on TaEIL1 gene expression, biochemical and physiological changes

Cadmium (Cd) contamination in agricultural soil is a major global concern among the multitude of human health and food security. Zinc oxide nanoparticles (ZnO-NPs) and plant growth promoting rhizobacteria (PGPR) have been known to combat heavy metal toxicity in crops. Herein, the study intended to explore the interactive effect of treatments mediated by inoculation of PGPR and foliar applied ZnO-NPs to alleviate Cd induced phytotoxicity in wheat plants which is rarely investigated. For this purpose, TaEIL1 expression, morpho-physiological, and biochemical traits of wheat were examined. Our results revealed that Cd reduced growth and biomass, disrupted plant physiological and biochemical traits, and further expression patterns of TaEIL1. The foliar application of ZnO-NPs improved growth attributes, photosynthetic pigments, and gas exchange parameters in a dose-additive manner, and this effect was further amplified with a combination of PGPR. The combined application of ZnO-NPs (100 mg L-1) with PGPR considerably increased the catalase (CAT; 52.4%), peroxidase (POD; 57.4%), superoxide dismutase (SOD; 60.1%), ascorbate peroxidase (APX; 47.4%), leading to decreased malondialdehyde (MDA; 47.4%), hydrogen peroxide (H2O2; 38.2%) and electrolyte leakage (EL; 47.3%) under high Cd (20 mg kg-1) stress. Furthermore, results revealed a significant reduction in roots (56.3%), shoots (49.4%), and grains (59.4%) Cd concentration after the Combined treatment of ZnO-NPs and PGPR as compared to the control. Relative expression of TaEIL1 (two homologues) was evaluated under control (Cd 0), Cd, ZnO-NPs, PGPR, and combined treatments. Expression profiling revealed a differential expression pattern of TaEIL1 under different treatments. The expression pattern of TaEIL1 genes was upregulated under Cd stress but downregulated under combined ZnO-NPs and PGPR, revealing its crucial role in Cd stress tolerance. Inferentially, ZnO-NPs and PGPR showed significant potential to alleviate Cd toxicity in wheat by modulating the antioxidant defense system and TaEIL1 expression. By inhibiting Cd uptake, and facilitating their detoxification, this innovative approach ensures food safety and security.

Zinc Oxide Nanoparticles Attenuated Neurochemical and Histopathological Alterations Associated with Aluminium Chloride Intoxication in Rats.

The present investigation explored the potential neuroprotective role of zinc oxide nanoparticles (ZnONPs) on aluminum chloride (AlCl3)-mediated Alzheimer's disease (AD)-like symptoms. Rats were distributed into four treatment groups equally: control, ZnONPs (4mg/kg b.wt.), AlCl3 (100mg/kg b.wt.), and ZnONPs + AlCl3 groups. Rats were treated for 42 consecutive days. ZnONPs injection into AlCl3-treated rats suppressed the development of oxidative challenge in the cortical and hippocampal tissues, as demonstrated by the decreased neuronal pro-oxidants (malondialdehyde and nitric oxide), and the increased glutathione and catalase levels. Additionally, ZnONPs injection showed anti-inflammatory potency in response to AlCl3 by decreasing levels of tumor necrosis factor-α and interleukin-1β. Moreover, pretreatment with ZnONPs prevented neuronal cell loss by decreasing the level of pro-apoptotic caspase-3 and enhancing the anti-apoptotic B cell lymphoma 2. Furthermore, ZnONPs ameliorated the disturbed acetylcholinesterase activity, monoamines (norepinephrine, dopamine, and serotonin), excitatory (glutamic and aspartic acids), and inhibitory amino acids (GABA and glycine) in response to AlCl3 exposure. These findings indicate that ZnONPs may have the potential as an alternative therapy to minimize or prevent the neurological deficits in AD model by exhibiting antioxidative, anti-inflammation, anti-apoptosis, and neuromodulatory effects.

Zinc oxide nanoparticles alleviated vanadium-induced inhibition by regulating plant hormone signal transduction and phenylpropanoid biosynthesis in maize seedlings (Zea may L.)

Our efforts were to identify the role of zinc oxide nanoparticles (ZnO-NPs) on the growth of maize (Zea may L.) under vanadium (V) stress. Transcriptome analysis was performed on maize leaves subjected to CK, V, and V+ZnO treatments. It was found that the application of ZnO-NPs significantly reduces V accumulation and toxicity in maize. A total of 5441 and 3003 differentially expressed genes (DEGs) were identified in the CK vs. V and V+ZnO vs. V comparisons, respectively. Of these detected genes, 3016 DEGs were specific to CV vs. V, and 608 DEGs were specific to V+ZnO vs V, respectively. These genes were primarily involved in plant hormone signal transduction and phenylpropanoid biosynthesis pathways. Under V treatment, ZnO-NPs caused an up-regulation of SAUR, AUX/IAA, ARRs, GID1, and BRIIs, which resulted in high levels of IAA, CTK, GA, BRs, and JAs in maize seedlings compared to those without ZnO-NPs. The addition of ZnO-NPs also leads to a significant decrease in total phenolics and lignin contents in maize seedlings by down-regulating CCR, HCT, CAD, 4CL, and C4H genes compared to those without ZnO-NPs. Overall, the findings suggest that ZnO-NPs can improve V-induced growth suppression by changing the expression of selected genes and constitute a simple and efficient strategy for alleviating V toxicity in high-V soils.

Driving Role of Zinc Oxide Nanoparticles with Different Sizes and Hydrophobicity in Metabolic Response and Eco-Corona Formation in Sprouts (Vigna radiata).

Zinc oxide nanoparticles (ZnO NPs) cause biotoxicity and pose a potential ecological threat; however, their effects on plant metabolism and eco-corona evolution between NPs and organisms remain unclear. This study clarified the molecular mechanisms underlying physiological and metabolic responses induced by three different ZnO NPs with different sizes and hydrophobicity in sprouts (Vigna radiata) and explored the critical regulation of eco-corona formation in root-nano systems. Results indicated that smaller-sized ZnO inhibited root elongation by up to 37.14% and triggered oxidative burst and apoptosis. Metabolomics confirmed that physiological maintenance after n-ZnO exposure was mainly attributed to the effective stabilization of nitrogen fixation and defense systems by biotransformation of the flavonoid pathway. Larger-sized or hydrophobic group-modified ZnO exhibited low toxicity in sprouts, with 0.89-fold upregulation of citrate in central carbon metabolism. This contributed to providing energy for resistance to NP stress through amino acid and carbon/nitrogen metabolism, accompanied by changes in membrane properties. Notably, smaller-sized and hydrophobic NPs intensely stimulated the release of root metabolites, forming corona complexes with exudates. The hydrogen-bonded wrapping mechanism in protein secondary structure and hydrophobic interactions of heterogeneous functional groups drove eco-corona formation, along with the corona evolution intensity of n-ZnO > s-ZnO > b-ZnO based on higher (α-helix + 3-turn helix)/β-sheet ratios. This study provides crucial insight into metabolic and eco-corona evolution in bionano fates.

Role of zinc oxide nanoparticles in alleviating sodium chloride-induced salt stress in sweet basil (Ocimum basilicum L.)

In this study, we examined the role of zinc oxide nanoparticles (ZnO NPs) on the growth facet, photosynthetic attributes, lipid peroxidation, electrolyte leakage (EL), and antioxidant activity of basil plants following growth subjected to different levels of sodium chloride-induced salinity [1.0 (control), 2.0, 3.0, 4.0, and 5.0 deci Siemens per meter (dSm–1)]. The foliage of 30-day-old plants was sprayed with an aqueous solution of ZnO NPs [(1.5/2.0 parts per million (ppm)]. Treated plants sampled at 75 days after sowing showed a concentration-dependent response against salinity for all studied growth, photosynthetic attributes, and other biochemical parameters. All growth parameters decreased with increasing salt levels in the soil. However, a direct relationship was observed for lipid peroxidation, EL, and all antioxidant stress markers, and all these parameters increased with the increased salinity levels in the soil. Moreover, ZnO NPs alone (1.5 or 2.0 ppm) or as a follow-up treatment with salinity (2.0 dSm–1 + 1.5 or 2.0 ppm ZnO, 3.0 dSm–1 + 1.5 or 2.0 ppm ZnO, 4.0 dSm–1 + 1.5 or 2.0 ppm ZnO, and 5.0 dSm–1 + 1.5 or 2.0 ppm ZnO) enhanced all the growth and photosynthetic parameters and protected the plants against salinity by reflecting the enhanced activity of antioxidants and decreasing EL and lipid peroxidation. The results of this study confirmed the ameliorating role of ZnO NPs against salt stress and screened out an effective dose of ZnO NPs (2.0 ppm) for growing Ocimum basilicum plant species in saline soil.

Enhancing Disinfection Efficiency of Wastewater Treatment Plant Effluent: The Role of ZnO Nanoparticles in Ultrasonic and UV-C Processes

Ultrasonic (US) and UV-C disinfection technologies have been successfully used in wastewater treatment plants (WWTPs) for disinfection purposes. The US technology is typically used as a pre-treatment step to break down larger particles and make them more susceptible to disinfection. The UV-C technology is commonly used as a final disinfection step in many WWTPs. The study aimed to assess the potential of using Zinc Oxide (ZnO) Nanoparticles (NPs) to improve the effectiveness of UV-C and US disinfection methods in treating wastewater effluent, offering a more comprehensive solution to wastewater treatment. In this experimental study, a Laboratory US Bath (40[Formula: see text]kHz) and a UV-C lamp (16[Formula: see text]W) were used. In order to investigate the effectiveness of ZnO NPs in the reduction of microbial load, 5[Formula: see text]mg/L of ZnO NPs was added to the effluent samples. Then, samples were examined for Total Coliform (TC) and Fecal Coliform (FC) reduction by the standard MPN/100[Formula: see text]mL test. The Chick‘s law was used to calculate the efficiency of microbial load. The relationship between variables was determined by regression analysis using Excel and SPSS-ver 21 software. In this study, the samples were examined in three groups: Samples that were only exposed to sonication or received UV-C radiation with Turbidity of 18 NTU (Group A) and Turbidity of 5 NTU (Group B), and Samples that received 5 mg/L of ZnO NPs (Group C). By increasing the time from 0.5 min to 10 min in the presence of UV-C, the amount of microbial population decreased, and 2 min was considered the optimal time. The maximum removal efficiencies by US for TC were 74.07,77.7, 85.1% (40∘C) and 92.5,100, and 100% (60∘C) in group A (in 30 min sonication), 85.7, 85.7, 100% (40∘C), respectively, and were 100% in other groups (B and C), respectively. The maximum removal efficiencies by US for FC were 76.4%, 88.2%, and 100% (40∘C) and 88.2%, 100%, and 100% (60∘C) in group A (in 30 min sonication), respectively, and were 100% in other groups (B and C). In this study, an important increase in the disinfection ability of ZnO NPs has been observed in the presence of US and UV-C. So, the ZnO NPs/UV-C and ZnO NPs/US processes are valuable alternatives to conventional disinfection processes by over 90% improvement of disinfection efficiency.

Possible therapeutic role of zinc oxide nanoparticles versus vanillic acid in testosterone-induced benign prostatic hyperplasia in adult albino rat: A histological, immunohistochemical and biochemical study

BackgroundThe search for alternative therapies for treatment of Benign prostatic hyperplasia (BPH) has been increasingly studied to avoid the common adverse effects of the usual regimens. Therefore, this study aimed at delineating possible mechanisms of benign prostatic hyperplasia (BPH) and possible therapeutic role of zinc oxide nanoparticles (ZnO-NPs) versus vanillic acid. MethodsForty rats were divided into five groups: control, sham control, Testosterone-induced BPH, BPH and Zn-NPs, and BPH and vanillic acid. Light microscopic, immune-histochemical; PCNA, Bcl-2, Bax, caspase-3, p-Akt and p-mTOR, histomorphometric analysis, MDA/SOD and GPx and were done. Gene expression of p-Akt, p-mTOR and survivin were evaluated. ResultsApplication of zinc oxide nanoparticles as well as vanillic acid significantly reduced prostatic index, epithelial thickness, stromal collagen fibers, expression of PCNA, Bcl2, p-Akt, p-mTOR and MDA tissue level (p < 0.05). Whereas expression of Bax and caspase 3, and tissue levels of SOD and GPx were significantly increased in groups treated with Zno-Nps and vanillic acid compared to that of BPH group. Zinc oxide nanoparticles showed a better effect than vanillic acid in alleviating BPH. ConclusionThese findings suggested that ZnO-NPs as well as VA ameliorated the histolo-pathological and biochemical effects of induced BPH, moreover they improved the proapoptotic and antioxidant parameters which ere induced in BPH. It is recommended to search for new agents to prevent the development and progression of BPH.

Evaluation of tribological behavior of a circulation oil with ionic liquid and hybrid additives

In this study, the synergistic effects of methyltrioctylammonium bis(trifluoromethylsulfonyl)imide [N1888] [NTf2] ionic liquid (IL) with zinc dialkyldithiophosphate (ZDDP) and zinc oxide (ZnO) nanoparticles (NPs) as hybrid additives in a circulation oil for steel–steel contacts at different temperatures. The wear test results indicated that the additions of single additives (IL, ZDDP, and ZnO NPs) could enhance the tribological performance of the circulation oil. Among these additives, the IL exhibited the most effective at the same weight concentration blended into the tested oil. The mixture of IL and ZDDP showed superior friction-reducing and wear-reducing properties compared to the IL + ZnO formulation. The hybrid additive formulation consisting of 0.5 wt% IL, 0.25 wt% ZDDP, and 0.25 wt% ZnO NPs exhibited excellent tribological properties at higher temperatures in the boundary lubrication regime. Analysis using scanning electron microscopy/energy dispersive X-ray reveals that all single additives contribute to the formation of a tribofilm wear mechanism. However, the role of ZnO NPs in the hybrid additive conditions was changed from the most likely tribosintering effect to the most likely nano bearing effect at 100 °C. The interactions among IL, ZDDP, and NPs examined in this study can provide fundamental insights for the development of future lubricants.

Protective role of zinc oxide nanoparticles in alleviating flumethrin-induced hepatic and renal toxicity in male albino rats

Protective role of zinc oxide nanoparticles in alleviating flumethrin-induced hepatic and renal toxicity in male albino rats

Deciphering the role of zinc oxide nanoparticles on physiochemical attributes of Zea mays exposed to saline conditions through modulation in antioxidant enzyme defensive system

Use of zinc oxide nanoparticles (ZnONPs) has the potential to increase the plant growth and development in agricultural sectors. Mode of application of NPs to plants is also of considerable importance. In present study, zinc oxide nanoparticles were prepared by using black seed extract and zinc salt. Characterized zinc oxide nanoparticles were then used to treat Zea mays L. in two types of treatments namely nano-priming and foliar nano-spray of zinc oxide nanoparticles. For each treatment a range of concentration was used i.e., 100, 200, 400, and 1000 mg/L. Experiment was conducted in randomized complete block design. Hydro-priming was used as a control. Whereas foliar spray was given after 30, 45, and 60 days of sowing. Plants were harvested after 90 days and various growth, physiological, biochemical, yield and stress parameters were studied. Results showed that monodispersed nanoparticles of average size of 45.56 nm were synthesized. Priming with ZnONPs showed better results as compared to foliar spray of ZnONPs. Highest germination (100%), Leaf length (350 cm), plant height (65 cm), and no. of leaves (10 leaves per plant) were recorded for corn plants with seed priming treatment of 200 mg/L of ZnONPs. These values were significantly higher than comparative positive control treatment values (salt-treated plants) as well. Whereas biochemical analysis also supported the results of growth parameters i.e., ZnONPs treated plants (200–1000 mg/L) showed higher values of sugar (0.6 µg), chlorophyll (1800 µg) and carotenoid content (400 µg). Protein and proline content was higher for zinc salt-treated (positive control) plants. Photosynthetic rate, CO2 sub-stomatal conductance, stomatal conductance and rate of transpiration was also higher for ZnONPs treated plants particularly in nano-primed plants. Whereas study of yield attributes showed highest cob length (14 cm), cob weight (80 g), cobs per plant (4) in ZnONPs treated plants that was significantly higher than the both controls. Stress studies of plant samples showed that peroxidase activity was highest in plants treated with 1000 mg/L zinc salt-treated salts, both in case of priming and foliar spray. Whereas catalase activity was found highest in ZnONPs (200 mg/L) foliar spray treated plants. Zinc content analysis of plant sample showed significantly higher amount of zinc in ZnONPs treated corn plants. It is concluded from present study that ZnONPs in priming treatment significantly enhanced the growth and yield attributes of corn plants through the balance of biochemical and stress indicators. Priming and foliar spray of ZnONPs also fortified the crop with enhanced zinc content. Future study with combination of both priming and foliar spray may be further optimized.

The therapeutic effect of nano-zinc on the optic nerve of offspring rats and their mothers treated with lipopolysaccharides

ABSTRACT This study investigated the toxicity of lipopolysaccharides (LPS) and the therapeutic role of zinc oxide nanoparticles (ZnO NPs) on the optic nerve of mother rats and their offspring treated with LPS. This study used eight male and forty female rats (Rattus norvegicus). Following mating, pregnant rats were separated into four groups: controls, LPS, ZnO NPs and LPS and ZnO NP-treated groups. LPS was injected twice during pregnancy. ZnO NPs were injected three times duringpregnancy, and a dose after birth. Mother rats and their offspring at 21daysold were sacrificed and separated from their optic nerve for histological and immunohistochemical examinations. Collected blood was collected from the mother rat for biochemical examination to evaluate superoxide dismutase-1 (SOD-1), catalase and malondialdehyde (MDA). This study discovered that ZnO NPs improved the histology of the optic nerve, decreased Cyclooxygenase-2 (COX-2) immunostaining, which overexpressed in the optic nerve of rats receiving LPS treatment and increased MDA. ZnO NPs also decreased the levels of the antioxidant enzymes such as SOD-1 and catalase, which had increased in the LPS-treated group. In conclusion, ZnO NPs injection into mother rats treated with LPS alleviated the markers of optic nerve injury in its offspring due to their antioxidant and neuroprotective effect.

Foliar Application of ZnO-NPs Influences Chlorophyll Fluorescence and Antioxidants Pool in Capsicum annum L. under Salinity

Zinc oxide nanoparticles (ZnO-NPs) have been proven to helpfully improve plant tolerance to several abiotic stresses. However, no information has been reported concerning the role of ZnO-NPs on pepper plants under salinity stress. Hence, this research aimed to evaluate the growth and physiological responses of pepper (Capsicum annum L.) plants to ZnO-NP foliar application under salinity. Plants were subjected to 0 (control), 25 (S1), 50 (S2), and 75 mM (S3) NaCl salinity with a foliar spray of 0, 1000, and 2000 ppm ZnO-NPs. Significant reductions were recorded in the chlorophyll index (SPAD) and chlorophyll fluorescence parameters, and in the activity and/or ratios of reduced ascorbate (AsA), reduced ascorbate/dehydroascorbic acid (AsA/DHA), reduced glutathione (GSH), reduced glutathione/oxidized glutathione (GSH/GSSG), and K+ content. There was a significant increase in proline content, electrolyte leakage (EL), H2O2 content, guaiacol peroxidase (GPX), ascorbate peroxidase (APX), superoxide dismutase (SOD), glutathione reductase (GR), dehydroascorbic acid (DHA), and oxidized glutathione (GSSG) activities, and in Na+ content and Na+/K+ ratio. Foliar treatments improved the salinity tolerance of the pepper plants by fortifying the antioxidant defense system, leaf fluorescence parameters, K+, and proline content, and in contrast, by decreasing the EL, Na+, and H2O2 levels. ZnO-NP foliar treatment efficiently improved the pepper plants’ physiological responses under salinity. Considering the overall results, 1000 ppm of ZnO-NPs would be advisable for the amelioration of salinity depression and to promote growth potential. However, at higher levels, the nanoparticle showed toxicity symptoms that limited its reliable applications.

Efficiency of Zinc Oxide Nanoparticles in Stimulating Germination and Seedling Growth of Soybean Plant Glycine max L. and its Protein Content

The results of this study gived a scientific view about the role of zinc oxide nanoparticles (ZnO) in the seeds germination and seedlings growth of soybean (Glycine max L.) when placed on the surface of solid Murashige and Skoog (MS) medium supplemented with concentrations (0, 20, 40, 60, 80, 100µg/ml) of those nanoparticles as stimulating factors. The results showed that the concentration of 40 μg/ml was superior to the percentage of germination of the growth seeds after 7 days which was 100 % at compared to the MS medium alone (control) which gave a percentage of germination of 75% after 15 days and also encouraged the same concentration to obtain the best length of the stems and roots groups at 10, 12 cm respectively, compared to the average lengths of seedlings growing on the control medium, with average lengths of 6 and 8.5 cm for stems and roots respectively. Also, this stimulation of zinc oxide nanoparticles was reflected on the growth and division parameters of cells through the protein content and DNA and RNA content of seedling cells, which increased with the presence of these nanoparticles, especially at a concentration of 40 μg /ml, as the protein content of cells reached 1.92 μg gm and with DNA, RNA contents 12.45 and 99.43 μg /gm respectively, compared to their ratios in seedling cells growing on MS medium.

Mitigation of salinity stress in barley genotypes with variable salt tolerance by application of zinc oxide nanoparticles.

Salinity has become a major environmental concern of agricultural lands, impairing crop production. The current study aimed to examine the role of zinc oxide nanoparticles (ZnO NPs) in reducing the oxidative stress induced by salinity and the overall improvement in phytochemical properties in barley. A total of nine different barley genotypes were first subjected to salt (NaCl) stress in hydroponic conditions to determine the tolerance among the genotypes. The genotype Annora was found as most sensitive, and the most tolerant genotype was Awaran 02 under salinity stress. In another study, the most sensitive (Annora) and tolerant (Awaran 02) barley genotypes were grown in pots under salinity stress (100 mM). At the same time, half of the pots were provided with the soil application of ZnO NPs (100 mg kg–1), and the other half pots were foliar sprayed with ZnO NPs (100 mg L–1). Salinity stress reduced barley growth in both genotypes compared to control plants. However, greater reduction in barley growth was found in Annora (sensitive genotype) than in Awaran 02 (tolerant genotype). The exogenous application of ZnO NPs ameliorated salt stress and improved barley biomass, photosynthesis, and antioxidant enzyme activities by reducing oxidative damage caused by salt stress. However, this positive effect by ZnO NPs was observed more in Awaran 02 than in Annora genotype. Furthermore, the foliar application of ZnO NPs was more effective than the soil application of ZnO NPs. Findings of the present study revealed that exogenous application of ZnO NPs could be a promising approach to alleviate salt stress in barley genotypes with different levels of salinity tolerance.

Determination of efflux activity in Enterococci by Hoechst accumulation assay and the role of zinc oxide nanoparticles in inhibition of this activity

BackgroundContribution of efflux pumps in development of antimicrobial resistance has been largely addressed in Gram negative and to a much lesser extent in Gram positive bacteria. Measuring accumulation of Hoechst (H) dye is known as a safe and rapid method for monitoring efflux activity in bacteria. Antimicrobial effects of metal nanoparticles have been attributed in part to inhibition of efflux pumps. This study aimed to first determine efflux activity in enterococci by Hoechst accumulation assay, and to second characterize the role of zinc oxide nanoparticles (ZnONPs) in inhibition of these pumps.ResultsIncreased accumulation of Hoechst dye showed more potential of ZnONPs in efflux inhibition compared with CCCP. H33258 represented more suitability for accumulation studies in enterococci. Two to six-fold reduction in minimum inhibitory concentration (MIC) values of antimicrobial agents in the presence of ZnONPs was observed.ConclusionsEfflux activity in enterococcal strains can be measured by H33258 accumulation assay. Application of ZnONPs as an efflux inhibitor, may rejuvenate the use of conventional antimicrobial agents against these bacteria.

The Potential Role of Zinc Oxide Nanoparticles in the Treatment of Diabetes Mellitus: An Updated Review

The Potential Role of Zinc Oxide Nanoparticles in the Treatment of Diabetes Mellitus: An Updated Review

Coactive role of zinc oxide nanoparticles and plant growth promoting rhizobacteria for mitigation of synchronized effects of heat and drought stress in wheat plants

This study intended to investigate the potential of the plant growth-promoting rhizobacteria (PGPR) and green synthesized zinc oxide nanoparticles (ZnO-NPs) (fruit extract of Papaya) against heat and drought stress in wheat. The characterization of green-synthesized ZnO-NPs was done through UV–vis spectrophotometry, Fourier-transform infrared spectrometry, X-ray diffraction and scanning electron microscopy. Individual and combination of PGPR (Pseudomonas sp.) and ZnO-NPs (10 ppm) amendments were tested in a pot experiment to upregulate wheat defence system under three stress groups (drought, heat and combined heat and drought stress). Drought and heat stress synergistically caused higher damage to wheat plants than individual heat and drought stress. This observation was confirmed with remarkable higher MDA and hydrogen peroxide (H2O2) content. Treated plants exposed to all stress groups showed an improved wheat growth and stress resistance through better biomass, photosynthetic pigments, nutrients, soluble sugars, protein and indole acetic acid content. Combination of ZnO-NPs and Pseudomonas sp. Protects the plants from all stress groups by producing higher proline, antioxidant enzymes i. e superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, glutathione reductase and dehydroascorbate reductase, and abscisic acid. Moreover, higher stress alleviation by this treatment was manifested by marked reduced electrolyte leakage, MDA and H2O2. The findings of current study confirmed that the synergistic actions of PGPR and ZnO-NPs can rescue plants from both single and combined heat and drought stress.

Assessing the Potential Role of Zinc Oxide Nanoparticles for Mitigating Cadmium Toxicity in Capsicum annuum L. Under In Vitro Conditions

Assessing the Potential Role of Zinc Oxide Nanoparticles for Mitigating Cadmium Toxicity in Capsicum annuum L. Under In Vitro Conditions

Zinc oxide nanoparticles attenuate prepubertal exposure to cisplatin- induced testicular toxicity and spermatogenesis impairment in rats

Cisplatin exposure represents a significant fertility problem for childhood cancer. In this study we examined the possible therapeutic role of Zinc oxide nanoparticles (ZnO-NPs) on Cisplatin (Cis) induced impairment in the spermatogenesis initiation during puberty. Seventy-two male rats aged 30 days were distributed into four equal groups: Control group; ZnO-NPs group (intraperitoneal i.p. injected with 5 mg/kg ZnO-NPs once a week for eight weeks); Cis group (i.p. injected with a single dose of 5 mg/kg); ZnO-NPs + Cis group (ZnO-NPs injection 2 hrs before Cis). Each group was subdivided into three groups and was sacrificed 7, 30 and, 60 days after cisplatin induction, which considered prepubertal at 37-day-old, productive at 60-day-old, and completely adult at 90-day-old. Biochemical, molecular, immunohistochemical, and ultrastructural examinations were studied on the testicular tissues and sperm samples. Group treated with Cis showed a decrease in the antioxidant activity and an increase in the reactive oxygen species (ROS), which in turn caused disruption in blood-testis barrier (BTB) proteins in the three different rat ages, and sperm DNA damage in the adult rats compared to control group (p < 0.05). Moreover, alterations in the structural and the ultrastructural morphology of the testis were observed compared with the control at 37, 60 and 90 days old rats. ZnO-NPs administration to Cis group manifested a significant decrease in the ROS that restored the BTB proteins, enhanced the architecture of the testis in the three different rat ages, and increased sperm DNA integrity in the adult rats. Zinc oxide nanoparticles could restore the male reproductive capacity in the adult rats after induction of Cis in the prepubertal period by promoting spermatogenesis.

Potassium silicate and zinc oxide nanoparticles modulate antioxidant system, membranous H+-ATPase and nitric oxide content in faba bean (Vicia faba) seedlings exposed to arsenic toxicity.

Current research focused on the potential role of zinc oxide nanoparticles (ZnONPs) and potassium (K+ ) in mitigation of arsenic (As) toxicity in Vicia faba L. seedlings. Faba bean seedlings were grown for 30days in potted soil. As stress curtailed root and shoot length, chlorophyll (Chl) content and net photosynthetic rate in V. faba seedlings. However, ZnONPs and K+ curtailed As stress in faba bean seedling through enhanced activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD) enzyme. Furthermore, ZnONPs and K+ significantly enhanced cysteine (Cys) content and serine acetyletransferase (SAT) activity in faba bean seedling exposed to As-toxificated soil. Application of ZnONPs and K+ curtailed superoxide ionic content and hydrogen peroxide (H2 O2 ) accumulation in V. faba seedlings exposed to As-polluted soil. Nitric oxide (NO) content also increased in faba bean seedlings treated with ZnONPs and K+ in normal and As-polluted soil. As stress alleviation was credited to reduce As uptake in faba bean seedlings treated with synergistic application of ZnONPs and K+ . It is proposed that K+ interaction with nanoparticles can be exploited at molecular level to understand the mechanisms involved in abiotic stress tolerance.