Growth and metabolism of pea (Pisum sativum) via biostimulants based on greener ZnO nanoparticles.

The purpose of this study was to identify the most important physiological and biological effects of green synthesis ZnO nanoparticles at a size of 65 nm, biostimulant (Folcare) and interaction biostimulant ZnO NPs on plant growth and metabolism. As our understanding of biostimulants' preventive and restorative modes of action has increased, it is critical to maintain the best crop output and quality possible. The reduction of fertilizers must be substituted by strategies that improve the nutrients uptake or their utilization by the plants. New processing methods are required as an efficient green process or an integrated (hybrid) process for different new technologies of interest. The effects of NPs, biostimulant, and combination ZnO NPs biostimulant on plant cell metabolism were examined in cytosol, chloroplast, and mitochondria of cells from the stems, roots, and leaves. The interaction NPs/biostimulant had a beneficial effect on the morphological and physiological indicators of plant health than when nanoparticles and biostimulant are applied separately. Folcare biostimulant coupled with zinc oxide nanoparticles improved pea crops growth. The improved of the quality of pea plants can be explained at least, in part, by increase in antioxidant activities during plant growth phenophase.

1. Highlighting the environmental effect the risk management of biostimulants based on ZnO bionanoparticles on the growth of pea- Identification of specific responses of plants to nano stresses: Analyzes of metabolitesAntioxidants enzymes2. Folcare coupled with zinc oxide bionanoparticles has a significant favorable influence on environmental conservation management by assisting plants in more effectively using nutrients.

Disturbance in Mineral Nutrition of Fenugreek Grown in Water Polluted with Nanosized Titanium Dioxide.

Nanoparticle (NPs) toxicity in the plant has drawn considerable attention. Fenugreek plants were cultivated for 16 days in hydroponic experiments and treated with 50 and 100 mg L- 1 titanium oxide (TiO2) NPs of two sizes [23 ± 1.6 nm (D1) and 83 ± 15 nm. (D2)]. The level of Ti in roots was higher than that of leaves and stems of plants treated with 100 mg L- 1 of TiO2 NPs (D1, D2). Ti caused a depletion of Ca and Mn compared with root control. The titane (Ti) damage to root cellular membranes could alter the plant's capacity to absorb and transport some nutrients. In our study, increasing the size of TiO2 NPs produced increases in the contents of Mg, Zn and Mn, and a decline in the contents of Fe and Cu in leaves and stems. In roots, Fe and Cu decreased after TiO2 NPs (D2) exposure. Changes in the fenugreek plant mineral composition were assessed, and physiological disturbances could be directly correlated with exposure to NPs.

Reserve Mobilization, Membrane Damage and Solutes Leakage in Fenugreek Imbibed with Urban Treated Wastewater.

The study aimed to determine the impact of treated domestic wastewater on seed germination, seedling growth and reserve mobilization from Fenugreek (Trigonellafoenum graecum L.). Seeds were germinated by soaking in distilled water (H2O) or wastewater treated with various methods: activated sludge processes (T1), facultative lagoons treatment (T2) and dilution. Results show high levels of organic matter (OM), suspended solids (TSS) and nutrients in TWW (T2) than that of TWW (T1). The embryo length and biomass of fenugreek imbibed by TWW were higher in TWW (T2) compared with TWW (T1). There was more reduction in free amino acids and soluble sugar contents in fenugreek treated with TWW (T1) than treated by TWW (T2). Important solutes leakage is recorded by measuring electric conductivity during seed imbibition with TWW. Improving the quality of wastewater by dilution (50%) stimulated germination of seeds and the growth of the tested plant. Moreover, it significantly reduces the solutes leakage and enhanced seed metabolites accumulation.

Zinc Oxide Nanoparticles Induced Oxidative Stress and Changes in the Photosynthetic Apparatus in Fenugreek (Trigonella foenum graecum L.).

The aim of this work was to study the toxicity of nanosheet zinc oxide nanoparticle with the size of 45 nm. The penetration of nanoparticles at an exposure by a localized spray does not make it possible to understand the mechanism of transport and bioavailability of the nanoparticles. In contrast, nanoparticles penetrated, via the roots, as a function of their diameter, the smaller ones having caused leaf stress (by translocation) at low concentrations. So that the choice of method of root application. Plants treated with 50 mg L-1 of ZnO-NPs presented disturbance in leaf due to changes in chlorophyll's biosynthesis. The highest value of the photosynthetic pigments was recorded at 5 mg L-1 of ZnO-NPs. However, the treatment with 50 mg L-1 of ZnO-NPs caused a decrease in the levels of chlorophyll a and b. Moreover, ZnO-NPs leaves significantly enhanced antioxidant enzymes activities.

Regulation of Mitochondrial and Cytosol Antioxidant Systems of Fenugreek (Trigonella foenum graecum L.) Exposed to Nanosized Titanium Dioxide.

In the present study, the interactions between nanoparticle (NP) exposure, root application and plants were examined. NPs are potentially responsible for conformational changes in polysaccharides, lipids, proteins, pectin, suberin and lignin molecules. 4 days of treatment with metal oxide caused a statistically significant increase in nicotinamide adénine dinucléotide oxidase activity in mitochondria and cytosol. Following exposure to TiO2NP, even lipid peroxidation levels decreased in the mitochondria (leaves, stem and root) and in the cytosol (leaves and root), although it increased in the cytosol of the stem. Malondialdehyde accumulation was found to be higher in the cytosol compared to the mitochondria of stems, and in the cytosol of leaves and roots. NPs caused alterations in metabolism, antioxidant enzyme activities (guaiacol peroxidase, catalase and ascorbate peroxidase) and the generation of oxidative stress. Effects caused by exposures to NPs were influenced by differences in metabolic responses in plant parts, plant compartments, the period of exposure and the NP doses.

Effects of nanosized titanium dioxide on the photosynthetic metabolism of fenugreek (Trigonella foenum-graecum L.).

The potential toxicity of nanoparticles in plants is scarce and contradictory. Despite the diversity of research efforts, a detailed explanation of the TiO2NPS effects in plant photosynthesis is still missing. The present work gives a new approach to examine the impact of the TiO2NPs on crop production (development and photosynthesis) and plant protection (tolerance and defense systems) in fenugreek (Trigonella foenum graecum L.). Seedlings were assessed in greenhouse trials to estimate the influence of TiO2NPs on physiological characters for 16 days. They were treated with TiO2NPs at a size less than 20nm. The results revealed that there were no significant effects on seedlings growth and biomass of stem, but a decrease in the fresh weight of leaves after TiO2NPs treatment. Plants treated with 100mg·L-1 of TiO2NPs presented a reduction and chlorosis in leaf area due to a significant decrease in the chlorophyll a and b contents. The highest value of the photosynthetic pigments was recorded at 50mg·L-1 of TiO2NPs. However, the treatment with 100mg·L-1 of TiO2NPs caused a decrease in the levels of chlorophyll a, b and of carotenoids. Both doses of TiO2NPs induced an accumulation of anthocyanins compared to the control after 16 days of seedling development. A nano-stress significantly decreased the flavonoids level, but increased that of polyphenols compared to control after 16 days of exposure. The decrease in the translocation ratio of flavonoids suggests that many of them contain an enediol group, which suggests that they may act as bidentate ligands for anatase TiO2NPs. Accordingly, nano-stressed leaves exhibited significantly enhanced GPOX, CAT and APX activity levels. On the contrary, GPOX and CAT activities were reduced substantially in stems treated with 100mg·L-1 TiO2NPs. The accumulation of MDA was found to be higher in stems than in leaves. This could be explained by the accumulation of nanoparticles in different organs; it could be that the stems are the favored targets of nanoparticles. These results underline the necessity for a deeper estimation of nanoparticle ecotoxicity and particularly concerning their interaction with plants.

Antihyperglycemic, antihyperlipidemic and antioxidant activities of traditional aqueous extract of Zygophyllum album in streptozotocin diabetic mice.

OBJECTIVE: The aim of this work was to investigate the antihyperglycemic, antioxidant and antihyperlipidemic effects of the aqueous extract of Zygophyllum album on streptozotocin (STZ)-induced diabetic mice. METHODS: Diabetes was induced in Swiss albino mice by the administration of STZ (45mg/kg b.w.) intraperitoneally. Aqueous extract of Z. album (100 and 300mg/kg b.w.) was administered by oral gavage once a day for a period of 15days. The effect of the extract on blood glucose, lipids, cholesterol levels in plasma, and also on enzymatic and non enzymatic antioxidants of defence systems such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) enzyme activities, and vitamin C, vitamin E and glutathione reductase (GSH) levels in liver and pancreas were studied. RESULTS: Our results showed that Z. album extract reduced the blood glucose, total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) levels in STZ-diabetic mice. It also significantly abolished the increase in MDA level, and GPx, SOD and CAT activities in both liver and pancreas. The levels of GSH, vitamin C and high-density lipoprotein (HDL) were significantly augmented in Z. album treated diabetic mice in comparison with control group. Our findings suggest that Z. album aqueous extract prevented the diabetic induced MDA levels via the enhancement of the tissue GSH and blood vitamin C levels. CONCLUSIONS: These results suggest that Z. album extract exerts the anti-diabetic and antihypercholesterolemic activities through its antioxidant properties.

Cadmium affects the glutathione/glutaredoxin system in germinating pea seeds.

The aim of this work was to investigate the effects of cadmium (Cd) on thiol and especially glutathione (GSH)-dependent reactions (glutathione content, glutaredoxin (Grx) content and activity, "glutathione" peroxidase (Gpx) activity, and glutathione reductase (GR) activity) in germinating pea seeds. Under Cd stress conditions, the overall activity as well as more specifically the expression of Grx C4 and Grx S12 increased. On the contrary, when incubated with Cd ions in vitro, the disulfide reductase activity of both isoforms was drastically inhibited. In the case of Grx C4, this correlated with the formation of protein dimers of 28 kDa as evidenced by electrophoresis analysis. Oxidative stress also affected the GSH status, since Cd treatment provoked (1) a pronounced stimulation in Gpx (a thioredoxin-dependent enzyme in plants) expression and (2) a drastic decrease in GR activity. These results are discussed in relation with the known contribution of Grx system to the thiol status during the germination of Cd-poisoned pea seeds.

Oxidative damage and redox change in pea seeds treated with cadmium.

Pea seeds (Pisum sativum L.) were germinated by soaking in distilled water or 5mM CdCl2 for 5 days. The relationships among Cd treatment, germination rate, embryonic axis growth, NAD(P)H levels and NAD(P)H oxidase activities in mitochondrial and peroxisomal fractions of cotyledons and embryonic axis were investigated. Heavy metal stress provoked a diminution in germination percent and embryonic axis growth, as compared to the control. A drastic disorder in reducing power was imposed after exposure to cadmium. Heavy metal caused a significant increase in the redox ratio of coenzymes. NADPH oxidase is considered to be oxidative stress-related enzymes. The NAD(P)H oxidase activities were strongly stimulated after Cd exposure. The changes in redox and oxidative properties are discussed in relation to the delay in seed germination and embryonic axis growth.

Cadmium induced mitochondrial redox changes in germinating pea seed.

Mitochondria play an essential role in producing the energy required for seedling growth following imbibition. Heavy metals, such as cadmium impair mitochondrial functioning in part by altering redox regulation. The activities of two protein redox systems present in mitochondria, thioredoxin (Trx) and glutaredoxin (Grx), were analysed in the cotyledons and embryo of pea (Pisum sativum L.) germinating seeds exposed to toxic Cd concentration. Compared to controls, Cd-treated germinating seeds showed a decrease in total soluble protein content, but an increase in -SH content. Under Cd stress conditions, Grx and glutathione reductase (GR) activities as well as glutathione (GSH) concentrations decreased both in cotyledons and the embryo. Similar results were obtained with the Trx system: Trx and NADPH-dependent thioredoxin reductase (NTR) activities were not stimulated, whereas total NAD(P) contents diminished in the embryo. However, Cd enhanced the levels of all components of the Trx system in the cotyledons. On the other hand, Cd caused a significant increase in oxidative stress parameters such as the redox ratio of coenzymes (oxidized to reduced forms) and NAD(P)H oxidase activities. These results indicate that Cd induces differential redox responses on different seed tissues. We suggest that neither Grx system nor Trx one may improve the redox status of mitochondrial thiols in the embryo of germinating pea seeds exposed to Cd toxicity, but in the cotyledons the contribution of Trx/NTR/NADPH can be established in despite the vulnerability of the coenzyme pools due to enzymatic oxidation.

Effect of cadmium on resumption of respiration in cotyledons of germinating pea seeds.

Pea seeds (Pisum sativum L.) were germinated by soaking in H2O or 5 mM CdCl2 during a 5-day period. Enzyme activities involved in respiratory metabolism were studied in cotyledons. Mitochondrial cytochrome c oxidase and NADH- and succinate-cytochrome c reductase activities were inhibited by cadmium treatment. The effects of Cd were performed in vivo and in vitro allowing to distinguish between the direct inhibition of the enzyme activities and the influence on the same enzymes into the cell environment. However, Cd exposure stimulated an enzyme activity of fermentation and inhibited the capacity of the enzyme inactivator (alcohol dehydrogenase inactivator). Moreover, the enzyme activities of NAD(P)H-recycling dehydrogenases via secondary pentose phosphate pathway, glucose-6-phosphate- and 6-phosphogluconate-dehydrogenases, were enhanced in Cd-stressed seeds. These disturbances suggest that cadmium may inflict a serious injury on renewal of respiration. The findings will help clarify the overall mechanisms that underlie cadmium-mediated toxicity in germinating seeds.

RETRACTED: Redox regulation of the glutathione reductase/iso-glutaredoxin system in germinating pea seed exposed to cadmium.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The editors would like to confirm the retraction of this paper at the request of the co-authors who had no prior knowledge on the actions of the lead author. This article contains data that was duplicated in: Smiri M, Chaoui A, Rouhier N, Gelhaye E, Jacquot JP, El Ferjani E. Cadmium Affects the Glutathione/Glutaredoxin System in Germinating Pea Seeds. Biol. Trace Elem. Res., 142 (2010) 93-105, doi:10.1007/s12011-010-8749-3; Smiri M, Chaoui A, Rouhier N, Gelhaye E, Jacquot JP, El Ferjani E. Effect of cadmium on resumption of respiration in cotyledons of germinating pea seeds. Ecotox. Environ. Safe., 73 (2010) 1246-1254, doi:10.1016/j.ecoenv.2010.05.015; Smiri M, Chaoui A, Rouhier N, Gelhaye E, Jacquot JP, El Ferjani E. NAD pattern and NADH oxidase activity in pea (Pisum sativum L.) under cadmium toxicity. Physiol. Mol. Biol. Plants, 16 (2010) 305-315, doi:10.1007/s12298-010-0033-7; Smiri M, Chaoui A, Rouhier N, Gelhaye E, Jacquot JP, El Ferjani E. Oxidative damage and redox change in pea seeds treated with cadmium. C. R. Biol., 333 (2010) 801-807, doi:10.1016/j.crvi.2010.09.002; Smiri M, Chaoui A, Rouhier N, Kamel C, Gelhaye E, Jacquot JP, El Ferjani E. Cadmium induced mitochondrial redox changes in germinating pea seed. BioMetals, 23 (2010) 973-984, doi:10.1007/s10534-010-9344-y. The co-authors apologize for this unfortunate incident.

NAD pattern and NADH oxidase activity in pea (Pisum sativum L.) under cadmium toxicity.

Seeds of pea (Pisum sativum L.) were germinated for 5 days by soaking in distilled water or 5 mM cadmium chloride. Compared to the control, cadmium (Cd) caused a reduction in percent germination and embryo growth. Pyridine nucleotide coenzyme concentrations were determined in cotyledons and embryonic axis. Nicotinamide adenine dinucleotide (NADH) oxidase activity was examined. Cd treatment caused a restriction in levels of reduced coenzyme form in the mitochondria and the post-mitochondrial fraction of cotyledons, and embryonic axis. The oxidized coenzyme form has been accumulated by Cd-treated mitochondria of both tissues. It was also found that NADH oxidase activity was stimulated. The relationship between coenzyme levels, seed germination, pea growth, and Cd stress has been reported.

Respiratory metabolism in the embryonic axis of germinating pea seed exposed to cadmium.

Seeds of pea (Pisum sativum L.) were germinated for 5d by soaking in distilled water or 5mM cadmium nitrate. The relationships among cadmium stress, germination rate, changes in respiratory enzyme activities and carbohydrates mobilization were studied. Two cell fractions were obtained from embryonic axis: (1) mitochondria, used to determine enzyme activities of citric acid cycle and electron transport chain, and (2) soluble, to measure some enzyme activities involved in fermentation and pentose phosphate pathway. Activities of malate- and succinate-dehydrogenases (MDH, SDH) and NADH- and succinate-cytochrome c reductases (NCCR, SCCR) were rapidly inhibited, while cytochrome c oxidase (CCO) was unaltered by cadmium treatment. However, this stimulated the NADPH-generating enzyme activities of the pentose phosphate pathway, glucose-6-phosphate- and 6-phosphogluconate-dehydrogenases (G6PDH, 6PGDH), as well as enzyme activity of fermentation, alcohol dehydrogenase (ADH), with concomitant inhibition in the capacity of enzyme inactivator (INADH). Moreover, Cd restricted carbohydrate mobilization in the embryonic axis. Almost no glucose and less than 7% of control fructose and total soluble sugars were available in the embryo tissues after 5d of exposure to cadmium. Cotyledonary invertase isoenzyme activity was also inhibited by Cd. The results indicate that cadmium induces disorder in the resumption of respiration in germinating pea seeds. The contribution of Cd-stimulated alternative metabolic pathways to compensate for the failure in mitochondrial respiration is discussed in relation to the delay in seed germination and embryonic axis growth.