The toxicity of zinc oxide (ZnO NPs) and polystyrene nanoplastics (PS NaPs) has been tested in different animal models; however, knowledge about their impact on mice remains incipient. The aim of the ...current study is to evaluate the effects of these nanomaterials on Swiss mice after their individual exposure to a binary combination of them. The goal was to investigate whether short exposure (three days) to an environmentally relevant dose (14.6 ng/kg, i.p.) of these pollutants would have neurotoxic, biochemical and genotoxic effects on the modelss. Data in the current study have shown that the individual exposure of these animals has led to cognitive impairment based on the object recognition test, although the exposure experiment did not cause locomotor and anxiogenic or anxiolitic-like behavioral changes in them. This outcome was associated with increased nitric oxide levels, thiobarbituric acid reactive species, reduction in acetylcholinesterase activity and with the accumulation of nanomaterials in their brains. Results recorded for the assessed parameters did not differ between the control group and the groups exposed to the binary combination of pollutants. However, both the individual and the combined exposures caused erythrocyte DNA damages associated with hypercholesterolemic and hypertriglyceridemic conditions due to the presence of nanomaterials. Based on the results, the toxicological potential of ZnO NPs and PS NaPs in the models was confirmed and it encouraged further in-depth investigations about factors explaining the lack of additive or synergistic effect caused by the combined exposure to the assessed pollutants.
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•ZnO NPs and PS NaPs do not induce locomotor changes or anxiety-like behavior in mice.•Exposure to ZnO NPs and PS NaPs, in separate, induces cognitive impairment during the object recognition test.•Mice exposed to nanomaterials, in separate, show REDOX imbalance.•ZnO NPs and PS NaPs, in separate, suppresse the AChE activity.•DNA damage has been observed in mice exposed to nanomaterials (in separate, or in combination).
Okara is the residue of hydrosoluble extract from soybean used for producing tofu and soydrink and presents high nutritional value. Therefore, it has important characteristics that make it an ...excellent alternative to being incorporated into “pâté”, i.e., a soft mixture of vegetables transformed into paste to which various flavorings are added. As a result, it has enhanced sensory properties. The aim of this study was to investigate the application of okara on the development of pâté formulations in order to yield a product with good acceptability and nutritional quality. Three formulations were prepared from the wet soybean residue, which showed high moisture (80.77%–81.42%), low lipid (5.62%–7.62%) and low calorie (95.14–108.14 kcal) contents. The sample with the lowest content of okara (34 g/100 g) showed the highest average in the acceptance test (8.0) and was also considered the tasters’ favorite one. It was significantly different from the others in the preference ranking test. The food product enriched with okara had β-carotene (0.411mg/100 mL), compounds with antioxidant activity and isoflavones (0.15 μmol/gFM) in its composition. The process developed by this study enabled to yield a vegetable paste enriched with okara, an agroindustrial by-product, as an interesting alternative to a new food product.
•The food product enriched with okara presented β-carotene compounds with good antioxidant activity in its composition.•The process developed for vegetable paste enriched with okara resulting in a low production value.•The sample with 34 g 100 g−1 of okara was also considered the tasters' favorite one.
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•PS NPs and ZnO NPs accumulate in Ctenopharyngodon idella.•Nanomaterials induced behavioral changes and genotoxic effects.•Groups exposed to PS NPs (in combination, or not, with ZnO ...NPs) showed increased oxidative stress.•Antioxidant levels did not appear to be enough to inhibit the effects of oxidative stress.•Not observe antagonistic, synergistic or additive effect of combination between PS NPs and ZnO NPs.
The toxicity of polystyrene nanoparticles (PS NPs) and ZnO nanoparticles (ZnO NPs), in combination is poorly known. Thus, the aim of the current study was to evaluate the effects of PS NPs (760 μg/L) on Ctenopharyngodon idella exposed to it, both in separate and in combination with ZnO NPs (760 μg/L), based on behavioral, biochemical and genotoxic biomarkers. Current data have indicated that PS NPs, for a short exposure period (3 days), both in separate and in combination with nanoparticles, have affected animals’ response to the mirror test. On the other hand, all treatments have equally induced C. idella inactivity towards alarm substances and DNA damage. There was increased oxidative stress, mainly in groups exposed to PS NPs (in combination, or not, with nanoparticles); although increased, the evaluated antioxidant levels did not appear to be enough to inhibit the effects of treatment-induced production of free radicals. Together, these results are likely co-responsible for the observed changes. The current study did not observe antagonistic, synergistic or additive effect on animals exposed to the combination between PS NPs and ZnO NPs; however, this outcome should not discourage the performance of similar studies focused on assessing the (eco)toxicity of pollutant mixtures comprising nanomaterials.
The increased contamination of surface water with plastic waste is proportional to the increased consumption of products that use them as raw material. However, the impact of these residues on ...aquatic biota remains limited, mainly when it comes to nanoplastics (NPs). Thus, the aim of the current study is to test the hypothesis that the exposure of Ctenopharyngodon idella juveniles to polystyrene nanoplastics (PS NPs) at low concentrations (0.04 ng/L, 34 ng/L and 34 μg/L), for 20 days, leads to DNA damage and has mutagenic and cytotoxic effects on their erythrocytes. Comet assay enabled observing that DNA damage (inferred from the greater tail length, DNA percentage in the tail and Olive tail moment) induced by PS NPs has increased as the pollutant concentrations have increased, as well as that the formation of micronuclei and other nuclear abnormalities was equitable in animals exposed to this pollutant. On the other hand, there were significant changes in erythrocyte shape and size, oxidative stress generation (NO levels, lipid peroxidation, hydrogen peroxide), antioxidant system inhibition (mediated by total hepatic glutathione) and PS NPs accumulation in the liver and brain of animals exposed to higher concentrations of it. Therefore, the current study has confirmed the initial hypothesis and enhanced the knowledge about the genotoxic, mutagenic and cytotoxic potential of PS NPs in freshwater fish at early developmental stage, relating these effects to biochemical changes and significant accumulation of these nanomaterials. Besides, it is a warning about the (eco) toxicological risk represented by these nanopollutants in aquatic environments.
Polystyrene nanoplastics are capable of inducing DNA damage, mutagenic and cytotoxicity changes in fish.
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•Short exposure to polystyrene nanoplastics (PS NPs) induces the formation of micronuclei and other nuclear abnormalities.•Ctenopharyngodon idella exposed to PS NPs show DNA damage.•PS NPs increase oxidative stress and decrease antioxidant defenses.
Although nanoplastics (NPs) are known to be toxic to several groups of animals, the effects of such a toxicity on freshwater benthic macroinvertebrate communities remain unknown. Thus, the aim of the ...current study is to test the hypothesis that polystyrene nanoplastics (PS NPs) (34 μg/L - 48 h of exposure) lead to biochemical damage in Aphylla williamsoni larvae. Data have evidenced high bioaccumulation factor in the analyzed individuals; this finding indicates that, similar to sediments, water is also part of aquatic systems and favors PS NPs retention in dragonfly larvae. Despite the lack of evidence about the interference of these pollutants in the nutritional status of the analyzed animals, their bioaccumulation was associated with REDOX imbalance featured by concomitant increase in the number of evaluated oxidative stress biomarkers (nitric oxide and lipid peroxidation) and antioxidants (antioxidant activity against the DPPH radical and the superoxide dismutase enzyme). On the other hand, the reduced acetylcholinesterase activity observed in larvae exposed to PS NPs has suggested the neurotoxic effect of these pollutants, with potential impact on their nerve and neuromuscular functions. Therefore, the current study is pioneer in showing that PS NPs can affect the health of the investigated larvae, even at small concentrations, for short exposure-time; this outcome reinforces the ecotoxicological risk of these pollutants for freshwater benthic macroinvertebrates.
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•Polystyrene nanoplastic (PS NPs) represent an ecological risk to bentonic macroinvertebrates.•PS NPs cause REDOX imbalance in Aphylla williamsoni larvae.•Larvae exposed to PS NPs show decreased acetylcholinesterase activity (neurotoxic effect).•PS NPs can accumulate in dragonfly larvae.
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•Short exposure of grass carp to polystyrene nanoplastics (PS NPs) causes accumulation of particles.•Ctenopharyngodon idella exposed to PS NPs show anti-predatory response deficit.•PS ...NPs alter visceral somatic and hepatosomatic indices in C. idella.•PS NPs induces oxidative stress and decreased antioxidant response.
The biometric, behavioral and biochemical toxicity of polystyrene nanoplastics (PS NPs) in aquatic freshwater vertebrates and in environmentally relevant concentrations remains poorly known. Thus, using different toxicity biomarkers we tested the hypothesis that the exposure of Ctenopharyngodon idella juveniles to small PS NPs concentrations (0.04 ng/L, 34 ng/L and 34 μg/L), for a short period-of-time, may affect their growth/development, individual and collective behavior, and biochemical parameters. Animals exposed to NPs did not show increased biometric parameters (i.e.: body biomass, total and standard length, peduncle height, head height and visceral somatic and hepatosomatic indices). Despite the lack of damage on the locomotor (open field test) and visual (visual stimulus test) abilities of the evaluated fish, the expected increase in locomotor activity during the vibratory stimulus test was not evident in animals exposed to NPs. Non-exposed animals were the only ones showing increased activity/locomotion time in the presence of the predatory stimulus during the individual anti-predatory response test. The behavior of animals directly confronted with a potential predator has evidenced the influence of NPs on shoals’ aggregation and on the distance kept by individuals from the predatory stimulus. These changes were associated with PS NPs accumulation in animals' brains, oxidative stress and increased acetylcholinesterase activity (hepatic and cerebral). Therefore, the current study has confirmed the initial hypothesis and showed that, even at low concentrations, PS NPs can affect the health of C. idella individuals at early life stage.
Summary
Plants continue to lose water from their leaves even after complete stomatal closure. Although this minimum conductance (gleaf‐res) has substantial impacts on strategies of water use and ...conservation, little is known about the potential drivers underlying the variability of this trait across species.
We thus untangled the relative contribution of water leaks from the cuticle and stomata in order to investigate how the variability in leaf morphological and anatomical traits is related to the variation in gleaf‐res and carbon assimilation capacity across 30 diverse species from the Brazilian Cerrado.
In addition to cuticle permeance, water leaks from stomata had a significant impact on gleaf‐res. The differential pattern of stomata distribution in the epidermis was a key factor driving this variation, suggesting the existence of a trade‐off between carbon assimilation and water loss through gleaf‐res. For instance, higher gleaf‐res, observed in fast‐growing species, was associated with the investment in small and numerous stomata, which allowed higher carbon assimilation rates but also increased water leaks, with negative impacts on leaf survival under drought. Variation in cuticle structural properties was not linked to gleaf‐res.
Our results therefore suggest the existence of a trade‐off between carbon assimilation efficiency and dehydration tolerance at foliar level.
Even after complete stomatal closure, plants lose water through the leaf cuticles and bark. This residual water conductance of leaves (gleaf‐res) and stems (gbark) can negatively impact plant water ...balance and affect plant survival in seasonally dry environments. However, little is known about the costs and benefits associated with such water leaks, especially on stem level.
Here, we characterized the structural and functional determinants of the variability in gbark across tropical savanna species to elucidate how variations in this trait are related to contrasting growth strategies.
The high variability in gbark across species was associated with morphoantomical properties of the outer bark (thickness, density and lenticel investment), and such characteristics influenced both stem transpiration and respiration, suggesting the existence of a trade‐off between water conservation and oxygen permeability, which reflected contrasting growth and dehydration tolerance strategies. For instance, species with higher gbark and gleaf‐res presented a fast resource acquisition strategy but were more prone to drought‐induced mortality by hydraulic failure. However, model simulations revealed that the relative contribution of gleaf‐res and gbark to overall water balance depended on whether leaves were less or more resistant to cavitation than the stems.
Synthesis. By combining correlative studies, experimental results and a modelling exercise, we provide a new understanding of the costs and benefits associated with the variability in gbark across tropical savanna species and a new perspective for studies of water relations and carbon economics in species from a hyperdiverse savanna.
By combining correlative studies, experimental results and a modelling exercise, we provide a new understanding of the costs and benefits associated with the variability in gbark across tropical savanna species and a new perspective for studies of water relations and carbon economics in species from a hyperdiverse savanna.
Soybean (Glycine max L.) is an economically important crop, and is cultivated worldwide, although increasingly long periods of drought have reduced the productivity of this plant. Research has shown ...that inoculation with arbuscular mycorrhizal fungi (AMF) provides a potential alternative strategy for the mitigation of drought stress. In the present study, we measured the physiological and morphological performance of two soybean cultivars in symbiosis with Rhizophagus clarus that were subjected to drought stress (DS). The soybean cultivars Anta82 and Desafio were grown in pots inoculated with R. clarus. Drought stress was imposed at the V3 development stage and maintained for 7 days. A control group, with well-irrigated plants and no AMF, was established simultaneously in the greenhouse. The mycorrhizal colonization rate, and the physiological, morphological, and nutritional traits of the plants were recorded at days 3 and 7 after drought stress conditions were implemented. The Anta82 cultivar presented the highest percentage of AMF colonization, and N and K in the leaves, whereas the DS group of the Desafio cultivar had the highest water potential and water use efficiency, and the DS + AMF group had thermal dissipation that permitted higher values of F
/F
, A, and plant height. The results of the principal components analysis demonstrated that both cultivars inoculated with AMF performed similarly under DS to the well-watered plants. These findings indicate that AMF permitted the plant to reduce the impairment of growth and physiological traits caused by drought conditions.
Despite the abundant evidence of impairments to plant performance and survival under hotter‐drought conditions, little is known about the vulnerability of reproductive organs to climate extremes. ...Here, by conducting a comparative analysis between flowers and leaves, we investigated how variations in key morphophysiological traits related to carbon and water economics can explain the differential vulnerabilities to heat and drought among these functionally diverse organs. Due to their lower construction costs, despite having a higher water storage capacity, flowers were more prone to turgor loss (higher turgor loss point; ΨTLP) than leaves, thus evidencing a trade‐off between carbon investment and drought tolerance in reproductive organs. Importantly, the higher ΨTLP of flowers also resulted in narrow turgor safety margins (TSM). Moreover, compared to leaves, the cuticle of flowers had an overall higher thermal vulnerability, which also resulted in low leakage safety margins (LSM). As a result, the combination of low TSMs and LSMs may have negative impacts on reproduction success since they strongly influenced the time to turgor loss under simulated hotter‐drought conditions. Overall, our results improve the knowledge of unexplored aspects of flower structure and function and highlight likely threats to successful plant reproduction in a warmer and drier world.
Summary statement
By conducting a comparative morphophysiological analysis between flowers and leaves, we showed that, due to their lower construction costs, flowers were more vulnerable to hotter‐drought events than leaves, thus evidencing possible threats to successful plant reproduction in a warmer and drier world
