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Papaya (Carica papaya) fruit has a short shelf life and suffers significant postharvest losses due to climacteric, instant ripening and perishable nature. Pre-storage hot water treatment (HWT) has significant potential to delay decay incidence in horticultural commodities. The present study was designed to evaluate effectiveness of HWT on ‘Red lady’ papaya fruit for minimizing the fruit decay and maintaining the quality during storage. Physiologically mature unripe ‘Red lady’ papaya fruit harvested from a commercial papaya orchard. Selected fruits were treated at three different hot water temperatures (50 °C, 52 °C and 54 °C) along with a control (room temp) for 10 minutes thereafter stored at 12 °C and 85–90% RH for four weeks. Different sensory evaluation, fruit quality scales and enzymatic activities were observed at weekly intervals. Fruit stored after 54 °C HWT showed lower weight loss (4.63%), decay incidence (5.1%) and higher fruit firmness (12.92 N) relative to control. Fruit treated at 52 °C HWT improved the fruit acidity, but total soluble solids decreased than control. The results revealed that ascorbic acid (33.33 mg/100 g), total phenolic contents (35 mg/g FW) total antioxidants (47.50% DPPH inhibition), and antioxidative enzyme activities were improved by 52 °C HWT. It is concluded that pre storage papaya fruit treatment (HWT @ 52 °C) preserves the quality of fruit throughout storage on the other hand at 54 °C HWT helps in decreased fruit decaying. It can be summarized that papaya fruit can be treated with hot water in the range of 52–54 °C to support the fruit shelf life and suppress fruit decay along with maintaining fruit quality.Practical applications: Papaya (Carica papaya L.) is a climacteric fruit which is highly susceptible to fungal attacks after harvest. Due to its perishable nature, it becomes decayed and huge amount of highly nutritious and medicinally important fruit is wasted. Recently people are more concerned about food safety which limits the use of fungicides for controlling the fruit decay in papaya. However, heat treatment has tremendous potential to control microbial decay, and keep food commodities safe from hazardous chemicals. In this study, the hot water treatment has successfully suppressed the fruit decay and maintained fruit quality of papaya in the course of entire period of cold storage. These findings indicated that use of hot water treatment is a practical approach for increasing the shelf life of papaya fruit.

Salmonella infection entails a cascade of attacks and defence measures. After breaching the intestinal epithelial barrier, Salmonella is phagocytosed by macrophages, where the bacteria encounter multiple stresses, to which it employs relevant countermeasures. Our study shows that, in Salmonella, the polyamine spermidine activates a stress response mechanism by regulating critical antioxidant genes. Salmonella Typhimurium mutants for spermidine transport and synthesis cannot mount an antioxidative response, resulting in high intracellular ROS levels. These mutants are also compromised in their ability to be phagocytosed by macrophages. Furthermore, it regulates a novel enzyme in Salmonella, Glutathionyl-spermidine synthetase (GspSA), which prevents the oxidation of proteins in E. coli. Moreover, the spermidine mutants and the GspSA mutant show significantly reduced survival in the presence of hydrogen peroxide in vitro and reduced organ burden in the mouse model of Salmonella infection. Conversely, in macrophages isolated from gp91phox−/− mice, we observed a rescue in the attenuated fold proliferation previously observed upon infection. We found that Salmonella upregulates polyamine biosynthesis in the host through its effectors from SPI-1 and SPI-2, which addresses the attenuated proliferation observed in spermidine transport mutants. Thus, inhibition of this pathway in the host abrogates the proliferation of Salmonella Typhimurium in macrophages. From a therapeutic perspective, inhibiting host polyamine biosynthesis using an FDA-approved chemopreventive drug, D, L-α-difluoromethylornithine (DFMO), reduces Salmonella colonisation and tissue damage in the mouse model of infection while enhancing the survival of infected mice. Therefore, our work provides a mechanistic insight into the critical role of spermidine in stress resistance of Salmonella. It also reveals a bacterial strategy in modulating host metabolism to promote their intracellular survival and shows the potential of DFMO to curb Salmonella infection.

High levels of 6:2 chlorinated polyfluorinated ether sulfonate (F‐53B), which is a substitute for perfluorooctane sulfonate (PFOS), are detected in various environmental matrices, wildlife, and humans. Chlorinated polyfluorinated ether sulfonate has received increased attention due to its potential risk to ecosystems. However, its toxicity in the soil organisms remains unclear. In the present study, a comparative investigation was conducted on the toxicities of 6:2 Chlorinated polyfluorinated ether sulfonate (F‐53B) and PFOS to the earthworm Eisenia. fetida. F‐53B was significantly more acutely toxic to earthworms than PFOS, with median lethal concentrations of 1.43 and 1.83 mmol/kg dry soil (~816 and 984 mg/kg dry soil), respectively. Although both F‐53B and PFOS, at 0.4 mmol/kg dry soil (=228 and 215 mg/kg dry soil) caused oxidative stress in earthworms, as evidenced by increased superoxide dismutase, peroxidase, and catalase activities as well as malondialdehyde level, the stress caused by F‐53B was higher than that caused by PFOS. In transcriptomic and metabolomic studies, negative effects of PFOS and F‐53B were observed on several metabolic processes in earthworms, including protein digestion and amino acid absorption, lipid metabolism, and the immune response. Compared with PFOS, F‐53B exhibited a weaker disruption of lipid metabolism, comparable potency for toxicity to the immune response, and a stronger potency in extracellular matrix destruction along with apoptosis and ferroptosis induction. Hence, our data suggest that F‐53B is more toxic than PFOS to earthworms. The findings provide some new insights into the potential toxicity of F‐53B to soil organisms. Environ Toxicol Chem 2024;43:170–181. © 2023 SETAC [ABSTRACT FROM AUTHOR]

Polystyrene is an inert polymer; however, sublethal effects have been observed in aquatic organisms exposed to microparticles of this plastic. Information on microplastic-related oxidative stress and related antioxidative responses as adverse effects and the underlying mechanisms of toxicity are limited. Daphnids are key contributors in aquatic ecosystems, linking primary producers to consumers and predators, facilitating energy transfer and thus being considered an ideal bioindicator organism to study the adverse effects of polystyrene fragments on the oxidative stress status and subsequent enzymatic antioxidant response. In the present study, neonates (≤ 24 h) and adult daphnids were acutely exposed to polystyrene fragments sieved to three size factions (< 25 µm, 45—63 µm, and 100—500 µm), and adverse effects were evaluated after 24 and 48 h. In adults, larger particles elicited reactive oxygen species by 61%, which was met with elevated superoxide dismutase (17%) and catalase activities (98%), restoring redox homeostasis within 48 h. However, in neonates, the reactive oxygen species increased with exposure to all polystyrene sizes within 24 h, and homeostasis was regained within 48 h without eliciting the enzymatic antioxidant defense. The adverse effects were associated with size fractions that were too large to be consumed, suggesting that leached additives may be involved. Further studies are needed to determine whether nonenzymatic antioxidants were responsible for neutralizing excess reactive oxygen species in neonates. [ABSTRACT FROM AUTHOR]

With increasing anthropic activities, a myriad of typical contaminants from industries, hospitals, and municipal discharges have been found which fail to be categorized under regulatory standards and are hence considered contaminants of "emerging concern". Since these pollutants are not removed effectively even by the conventional treatment systems, they tend to inflict potential threats to both human and aquatic life. However, microalgae-mediated remediation strategies have recently gained worldwide importance owing to their role in carbon fixation, low operational cost, and production of high-value products. In this study, centric diatom Chaetoceros neogracilis was exposed to different concentrations of estradiol (E2)-induced synthetic media ranging from 0 to 2 mg L−1, and its impact on the antioxidative system of algae was investigated. The results demonstrate that the nutrient stress caused a strong oxidative response elevating the superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in the 2 mg L−1 E2-treated diatom cultures. However, the specific activity of the H2O2 radical scavenging enzymes like catalase (CAT) was inhibited by the E2 treatment, while that of ascorbate peroxidase (APX) remained comparable to the control (0 mg L−1 of E2). Thus, the study reveals the scope of diatoms as potential indicators of environmental stress even under the varying concentration of a single contaminant (E2). [ABSTRACT FROM AUTHOR]

Zinc insufficiency is a nutritional trouble worldwide, especially in developing countries. In the current study, an experiment was conducted to evaluate the effect of supplementation of MS media culture with different concentrations of ZnO nanoparticles (NPs) (0, 10, 20, 40, 80, and 160 ppm) on growth, nutrient uptake, and some physiological parameters of 7-days-old mung bean seedlings. ZnO NPs enhanced the Zn concentration of mung bean from 106.41 in control to more than 4600 µg/g dry weight in 80 and 160 ppm ZnO NPs treated seedlings. Our results showed that ZnO NPs in the concentration range from 10 to 20 ppm had a positive influence on growth parameters and photosynthetic pigments. Higher levels of ZnO NPs negatively affected seedling's growth by triggering oxidative stress which in turn caused enhancing antioxidative response in seedlings including polyphenol oxidase and peroxidase activity as well as phenolic compounds and anthocyanine contents. Considering the positive effects of ZnO NPs treatment on mungbean seedlings growth, micronutrents, protein and shoot phenolics content, 20 ppm is recommended as the optimal concentration for biofortification. Our findings confirm the capability of ZnO NPs in the remarkable increase of Zn content of mungbean seedlings which can be an efficient way for plant biofortification and dealing with environmental stress. [ABSTRACT FROM AUTHOR]

Extended drought affects the production and quality of wheat (Triticum aestivum L.), one of the world's most important food crops. Breeding for increased drought resistance is becoming increasingly important due to the rising demand for food production. Four old traditional Croatian wheat cultivars were used in the present study to examine the early antioxidant response of flag leaves to desiccant-stimulated drought stress and to identify drought-tolerant cultivars accordingly. The results indicate that the enzymatic antioxidant system plays the most significant role in the early response of adult wheat plants to drought stress and the removal of excessive H2O2, particularly GPOD and APX. Nada and Dubrava cultivars revealed the strongest activation of the enzymatic defense mechanism, which prevented H2O2 accumulation and lipid peroxidation. Additionally, the Nada cultivar also showed increased synthesis of proline and specific phenolic compounds, which both contribute to the increased stress tolerance. Among the cultivars investigated, cultivar Nada has the broadest genetic base, which may explain why it possesses the ability to activate both enzymatic and non-enzymatic defense mechanisms in an early response to drought stress. This suggests that old traditional wheat cultivars with broad genetic bases can be a valuable source of drought tolerance, which is especially important given the current climate change. [ABSTRACT FROM AUTHOR]

Ichthyophthirius multifiliis, a ciliated parasite causing ichthyophthiriasis (white spot disease) in freshwater fishes, results in significant economic loss to the aquaculture sector. One of the important predisposing factors for ichthyophthiriasis is low water temperature (i.e., below 20°C), which affects the health and makes freshwater fishes more susceptible to parasitic infections. During ichthyophthiriasis, fishes are stressed and acute immune reactions are compromised, which enables the aquatic bacterial pathogens to simultaneously infect the host and increase the severity of disease. In the present work, we aimed to understand the parasite-bacteria co-infection mechanism in fish. Later, Curcuma longa (turmeric) essential oil was used as a promising management strategy to improve immunity and control coinfections in fish. A natural outbreak of I. multifiliis was reported (validated by 16S rRNA PCR and sequencing method) in Pangasianodon hypophthalmus from a culture facility of ICAR-CIFRI, India. The fish showed clinical signs including hemorrhage, ulcer, discoloration, and redness in the body surface. Further microbiological analysis revealed that Aeromonas hydrophila was associated (validated by 16S rRNA PCR and sequencing method) with the infection and mortality of P. hypophthalmus, confirmed by hemolysin and survival assay. This created a scenario of co-infections, where both infectious agents are active together, causing ichthyophthiriasis and motile Aeromonas septicemia (MAS) in P. hypophthalmus. Interestingly, turmeric oil supplementation induced protective immunity in P. hypophthalmus against the co-infection condition. The study showed that P. hypophthalmus fingerlings supplemented with turmeric oil, at an optimum concentration (10 ppm), exhibited significantly increased survival against co-infection. The optimum concentration induced anti-stress and antioxidative response in fingerlings, marked by a significant decrease in cortisol and elevated levels of superoxide dismutase (SOD) and catalase (CAT) in treated animals as compared with the controls. Furthermore, the study indicated that supplementation of turmeric oil increases both non-specific and specific immune response, and significantly higher values of immune genes (interleukin-1b, transferrin, and C3), HSP70, HSP90, and IgM were observed in P. hypophthalmus treatment groups. Our findings suggest that C. longa (turmeric) oil modulates stress, antioxidant, and immunological responses, probably contributing to enhanced protection in P. hypophthalmus. Hence, the application of turmeric oil treatment in aquaculture might become a management strategy to control co-infections in fishes. However, this hypothesis needs further validation. [ABSTRACT FROM AUTHOR]

Ichthyophthirius multifiliis, a ciliated parasite causing ichthyophthiriasis (white spot disease) in freshwater fishes, results in significant economic loss to the aquaculture sector. One of the important predisposing factors for ichthyophthiriasis is low water temperature (i.e., below 20°C), which affects the health and makes freshwater fishes more susceptible to parasitic infections. During ichthyophthiriasis, fishes are stressed and acute immune reactions are compromised, which enables the aquatic bacterial pathogens to simultaneously infect the host and increase the severity of disease. In the present work, we aimed to understand the parasite–bacteria co-infection mechanism in fish. Later, Curcuma longa (turmeric) essential oil was used as a promising management strategy to improve immunity and control co-infections in fish. A natural outbreak of I. multifiliis was reported (validated by 16S rRNA PCR and sequencing method) in Pangasianodon hypophthalmus from a culture facility of ICAR-CIFRI, India. The fish showed clinical signs including hemorrhage, ulcer, discoloration, and redness in the body surface. Further microbiological analysis revealed that Aeromonas hydrophila was associated (validated by 16S rRNA PCR and sequencing method) with the infection and mortality of P. hypophthalmus, confirmed by hemolysin and survival assay. This created a scenario of co-infections, where both infectious agents are active together, causing ichthyophthiriasis and motile Aeromonas septicemia (MAS) in P. hypophthalmus. Interestingly, turmeric oil supplementation induced protective immunity in P. hypophthalmus against the co-infection condition. The study showed that P. hypophthalmus fingerlings supplemented with turmeric oil, at an optimum concentration (10 ppm), exhibited significantly increased survival against co-infection. The optimum concentration induced anti-stress and antioxidative response in fingerlings, marked by a significant decrease in cortisol and elevated levels of superoxide dismutase (SOD) and catalase (CAT) in treated animals as compared with the controls. Furthermore, the study indicated that supplementation of turmeric oil increases both non-specific and specific immune response, and significantly higher values of immune genes (interleukin-1β, transferrin, and C3), HSP70, HSP90, and IgM were observed in P. hypophthalmus treatment groups. Our findings suggest that C. longa (turmeric) oil modulates stress, antioxidant, and immunological responses, probably contributing to enhanced protection in P. hypophthalmus. Hence, the application of turmeric oil treatment in aquaculture might become a management strategy to control co-infections in fishes. However, this hypothesis needs further validation.

The positive impact on restoring soil functionality, decreasing toxic elements (TE) bioaccessibility, and enhancing soil physicochemical and biological parameters established a consensus on considering a Miscanthus × giganteus convenient species for phytomanaging wide TE contaminated areas. Nevertheless, information about the plant's mode of reaction to elevated soil multi-TE concentrations is still scarce. For the sake of investigating the miscanthus response to stressful TE concentrations, an ex-situ pot experiment was initiated for 18 months, with three miscanthus cultivars referred to as B, U, and A planted in soils with gradient Cd, Pb, and Zn concentrations. A non-contaminated control soil was introduced as well, and plants were cultivated within. Results revealed that the long exposure to increasing soil TE concentrations caused the number of tillers per plant to decline and the TE concentrations in the leaves to boost progressively with the soil contamination. The photosynthetic pigments (chlorophyll a, b, and carotenoids) were negatively affected as well. However, the phenolic compounds, flavonoids, tannins, and anthocyanins, along with the antioxidant enzymatic activities of superoxide dismutase, ascorbate peroxidase, and glutathione reductase elevated progressively with the TE concentration and exposure duration. Conclusively, miscanthus plants demonstrated an intensified and synchronized antioxidative activity against the TE concentration. [ABSTRACT FROM AUTHOR]

Due to climate change in recent years, there has been an increasing water deficit during the winter wheat sowing period. This study evaluated six Croatian winter wheat varieties' physiological, biochemical, and molecular responses under two drought stress levels at the germination/seedling growth stage. Lipid peroxidation was mainly induced under both drought stress treatments, while the antioxidative response was variety-specific. The most significant role in the antioxidative response had glutathione along with the ascorbate-glutathione pathway. Under drought stress, wheat seedlings responded in proline accumulation that was correlated with the P5CS gene expression. Expression of genes encoding dehydrins (DHN5, WZY2) was highly induced under the drought stress in all varieties, while genes encoding transcription factors were differentially regulated. Expression of DREB1 was upregulated under severe drought stress in most varieties, while the expression of WRKY2 was downregulated or revealed control levels. Different mechanisms were shown to contribute to the drought tolerance in different varieties, which was mainly associated with osmotic adjustment and dehydrins expression. Identifying different mechanisms in drought stress response would advance our understanding of the complex strategies contributing to wheat tolerance to drought in the early growth stage and could contribute to variety selection useful for developing new drought-tolerant varieties. [ABSTRACT FROM AUTHOR]

During cultivation, wheat is exposed to several abiotic and/or biotic stress conditions that may adversely impact the wheat yield and quality. The impact of abiotic stress caused by nitrogen deficiency and biotic stress caused by phytopathogenic fungus Fusarium culmorum on biomarkers of oxidative stress in the flag leaf of nine winter wheat varieties (Ficko, U-1, Galloper, BC Mandica, BC Opsesija, Ingenio, Isengrain, Felix, and Bezostaya-1) was analyzed in this study. Hydrogen peroxide concentration and lipid peroxidation level were measured as indicators of oxidative stress, while the antioxidant response was determined by measuring the concentration of phenolic compounds and activities of antioxidant enzymes. Wheat variety and nitrogen treatment had a significant effect on all examined biomarkers of oxidative stress in the flag leaf, while the impact of Fusarium treatment was less pronounced. The most significant impact on the measured stress biomarkers had a low nitrogen level, which mainly increased hydrogen peroxide concentration and lipid peroxidation level and decreased activities of antioxidant enzymes in most varieties. The obtained results were discussed and compared with the previous study in which biochemical analyzes were performed on the wheat spike. There was no significant strong correlation between flag leaf and spike response in the measured parameters, which, in addition to the variety-specific response, also indicates a tissue-specific antioxidant response.

Randomly collected samples of parsley and celery from different localities were analysed to determine their quality based on arsenic concentrations, phenolic constituents and the antioxidant capacity of their edible parts. Arsenic concentrations were found in the range: parsley root (0.16 mg/g d.m.) < celery root (0.19 mg/g d.m.) < parsley leaf (0.35 mg/g d.m.) < celery leaf (0.45 mg/g d.m.). Total phenolic contents in roots were similar in both species and varied significantly depending on the cultivation site: 5.03-9.18 mg eqGA/g DE in parsley and 5.04-8.50 mg eqGA/g DE in celery. Lower total flavonoids content was recorded in celery. Among the phenolic acids, ferulic, chlorogenic and several cinnamic acids dominated. Apigenin and its glucosides dominated among flavonoids. Based on the principal component analysis (PCA) it can be concluded that the As content varied depending on the geographical origin of the samples. Also, phenolic compounds showed a significant contribution on PCA clustering, indicating that the cultivation site has a clear significant impact on the metabolites profile, while As content in plants did not significantly affect phenolic compound profile.

Extended drought affects the production and quality of wheat (Triticum aestivum L.), one of the world’s most important food crops. Breeding for increased drought resistance is becoming increasingly important due to the rising demand for food production. Four old traditional Croatian wheat cultivars were used in the present study to examine the early antioxidant response of flag leaves to desiccant-stimulated drought stress and to identify drought-tolerant cultivars accordingly. The results indicate that the enzymatic antioxidant system plays the most significant role in the early response of adult wheat plants to drought stress and the removal of excessive H2O2, particularly GPOD and APX. Nada and Dubrava cultivars revealed the strongest activation of the enzymatic defense mechanism, which prevented H2O2 accumulation and lipid peroxidation. Additionally, the Nada cultivar also showed increased synthesis of proline and specific phenolic compounds, which both contribute to the increased stress tolerance. Among the cultivars investigated, cultivar Nada has the broadest genetic base, which may explain why it possesses the ability to activate both enzymatic and non-enzymatic defense mechanisms in an early response to drought stress. This suggests that old traditional wheat cultivars with broad genetic bases can be a valuable source of drought tolerance, which is especially important given the current climate change.

Salmonella infection entails a cascade of attacks and defence measures. After breaching the intestinal epithelial barrier, Salmonella is phagocytosed by macrophages, where the bacteria encounter multiple stresses, to which it employs relevant countermeasures. Our study shows that, in Salmonella, the polyamine spermidine activates a stress response mechanism by regulating critical antioxidant genes. Salmonella Typhimurium mutants for spermidine transport and synthesis cannot mount an antioxidative response, resulting in high intracellular ROS levels. These mutants are also compromised in their ability to be phagocytosed by macrophages. Furthermore, it regulates a novel enzyme in Salmonella, Glutathionyl-spermidine synthetase (GspSA), which prevents the oxidation of proteins in E. coli. Moreover, the spermidine mutants and the GspSA mutant show significantly reduced survival in the presence of hydrogen peroxide in vitro and reduced organ burden in the mouse model of Salmonella infection. Conversely, in macrophages isolated from gp91phox -/- mice, we observed a rescue in the attenuated fold proliferation previously observed upon infection. We found that Salmonella upregulates polyamine biosynthesis in the host through its effectors from SPI-1 and SPI-2, which addresses the attenuated proliferation observed in spermidine transport mutants. Thus, inhibition of this pathway in the host abrogates the proliferation of Salmonella Typhimurium in macrophages. From a therapeutic perspective, inhibiting host polyamine biosynthesis using an FDA-approved chemopreventive drug, D, L-α-difluoromethylornithine (DFMO), reduces Salmonella colonisation and tissue damage in the mouse model of infection while enhancing the survival of infected mice. Therefore, our work provides a mechanistic insight into the critical role of spermidine in stress resistance of Salmonella. It also reveals a bacterial strategy in modulating host metabolism to promote their intracellular survival and shows the potential of DFMO to curb Salmonella infection., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

With the abundant production and wide application of zinc oxide nanoparticles (ZnONPs), the potential health risks of ZnONPs have raised serious concerns. Oxidative stress is recognized as the most important outcome of the toxicity induced by ZnONPs. The Nrf2-Keap1 system and its downstream antioxidative genes are the fundamental protective mechanisms for redox hemeostasis. However, the detailed mechanisms of Nrf2 activation in ZnONPs-treated endothelial cells and murine blood vessels have yet to be elucidated. Herein, we show that Nrf2 was activated and played a negative role in cell death induced by ZnONPs. Moreover, we demonstrate that HO-1 was the most extensively upregulated antioxidative gene-activated by Nrf2. Forced overexpression of HO-1, pharmacological activation of HO-1 with the agonists RTA-408 (omaveloxolone, an FDA-approved drug) and RTA-402 repressed cell death, and treatment with HO-1 antagonist SnPP exacerbated the cell death. Importantly, loss of HO-1 diminished the cytoprotective role induced by Nrf2 in ZnONPs-treated HUVEC cells, indicating that the Nrf2-HO-1 axis was the crucial regulatory mechanism for the antioxidative response in the context of ZnONPs-induced endothelial damage. Mechanistically, we demonstrate that the p62-Keap1 axis was not involved in the activation of Nrf2. Intriguingly, the degradation half-life of Nrf2 in HUVEC cells was increased from less than 1 h under quiescent conditions to approximately 6 h under ZnONPs treatment condition; moreover, ZnONPs treatment induced activation of Nrf2/HO-1 and accumulation of ubiquitin in the aorta ventralis of mouse, suggesting that the ubiquitin-proteasome system had been perturbed, which subsequently led to the stabilization of Nrf2 and activation of HO-1. This study might contribute to a better understanding of ZnONPs-associated toxicity. [ABSTRACT FROM AUTHOR]

Main conclusions: Sugar-mediated osmotic acclimation and a strong antioxidative response reduce drought-induced biomass loss at the vegetative stage in rice. A clear understanding of the physiological and biochemical adaptations to water limitation in upland and aerobic rice can help to identify the mechanisms underlying their tolerance to low water availability. In this study, three indica rice varieties-IR64 (lowland), Apo (aerobic), and UPL Ri-7 (upland)-, that are characterized by contrasting levels of drought tolerance, were exposed to drought at the vegetative stage. Drought-induced changes in biomass, leaf metabolites and oxidative stress markers/enzyme activities were analyzed in each variety at multiple time points. The two drought-tolerant varieties, Apo and UPL Ri-7 displayed a reduced water use in contrast to the susceptible variety IR64 that displayed high water consumption and consequent strong leaf dehydration upon drought treatment. A sugar-mediated osmotic acclimation in UPL Ri-7 and a strong antioxidative response in Apo were both effective in limiting the drought-induced biomass loss in these two varieties, while biomass loss was high in IR64, also after recovery. A qualitative comparison of these results with the ones of a similar experiment conducted in the field at the reproductive stage showed that only Apo, which also in this stage showed the highest antioxidant power, was able to maintain a stable grain yield under stress. Our results show that different metabolic and antioxidant adaptations confer drought tolerance to aerobic and upland rice varieties in the vegetative stage. The effectiveness of these adaptations differs between developmental stages. Unraveling the genetic control of these mechanisms might be exploited in breeding for new rice varieties adapted to water-limited environments. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD/emphysema) is a life-threatening disorder and there are few effective therapies. Cigarette smoke-induced oxidative stress, airway inflammation, and apoptosis of lung cells have been reported to be involved in the pathogenesis of COPD/emphysema and lead to alveolar septal destruction. Here we show that the expression level of FCH and double SH3 domains 1 (FCHSD1) was drastically increased in mice in response to elastase instillation, an experimental model of COPD. FCHSD1 is a member of the F-BAR family with two SH3 domains. We found that Fchsd1 knockout (Fchsd1-/-) mice were protected against airspace enlargement induced by elastase. Elastase-instilled lungs of Fchsd1-/- mice showed reduced inflammation and apoptosis compared with WT mice. We also found that elastase-induced reduction of Sirtuin 1 (SIRT1) levels, a histone deacetylase reported to protect against emphysema, was attenuated in the lungs of Fchsd1-/- mice. Furthermore, FCHSD1 deficiency enhanced nuclear translocation of nuclear factor-like 2 (NRF2), a redox-sensitive transcription factor, following H2O2 stimulation. Conversely, Fchsd1 overexpression inhibited NRF2 nuclear translocation and increased the reduction of SIRT1 levels. Notably, FCHSD1 interacted with NRF2 and SNX9. Our results show that FCHSD1 forms a multicomplex with NRF2 and SNX9 in the cytosol that prevents NRF2 from translocating to the nucleus. We propose that FCHSD1 promotes initiation of emphysema development by inhibiting nuclear translocation of NRF2, which leads to down-regulation of SIRT1. [ABSTRACT FROM AUTHOR]

Ionic liquids are widely used for lipid and pigment extractions from microalgae. It is possible that ionic liquids are discharged into environments. The evaluation of growth performance and antioxidative response of ionic liquids to microalgae is helpful to explore the stress regulation mechanism and investigate possible environmental risk. Ionic liquids induce production of reactive oxygen species (ROS) to microalgae. These oxidative stresses are possible from cations, anions, and salinity. In this study, the growth inhibitions of [BMIM]Br, [BMIM]Cl, [EMIM]Cl, and [EMIM]EtOSO3 to Anabaena cylindrica, Chlorella pyrenoidesa, and Dunaliella salina were evaluated. It was interesting that Br− and two kinds of cations, [BMIM] and [EMIM], had significant effects on growth inhibitions of these microalgae. IC50 values of these ionic liquids for A. cylindrica, C. pyrenoidesa, and D. salina were also estimated based on the results of growth inhibitions. It was proved that [EMIM]Cl is relatively harmless to C. pyrenoidesa and D. salina, and [EMIM]EtOSO3 is relatively or practically harmless to C. pyrenoidesa. [BMIM]Br and [BMIM]Cl are practically harmless to A. cylindrica and C. pyrenoidesa, and relatively harmless to D. salina. More than 0.8 g/L [EMIM]EtOSO3 led to bleaching of both A. cylindrica and D. salina at 48 h which was shown that the anion, EtOSO3−, had higher inhibition to A. cylindrica and D. salina than Cl−. In addition, high concentration of ionic liquids led to reductions of chlorophyll content in these three kinds of microalgae, increase of ROS levels and malondialdehyde contents for most of the cases. High concentration of ionic liquids also increased the activities of superoxide dismutase in three kinds of microalgae. There were positive correlations between ROS levels or MDA content, and inhibitions ratios of these ionic liquids to microalgae except [EMIM]Cl to A. cylindrica. These antioxidant enzymes were beneficial for reducing the ROS induced by ionic liquids. [ABSTRACT FROM AUTHOR]

Onion (Allium cepa L.) is a biennial crop of high commercial value in Pakistan. Onion is considered as salt sensitive plant species. The present investigation was carried out to investigate the effect of salinity on onion and its alleviation through exogenously applied gibberellic acid (GA3; 100 mg L-1). Foliar application of GA3 (100 mg L-1) was applied on onion seedlings grown under three levels (0, 2 or 4 dS m-1) of salinity after 45 days of sowing. Results revealed that growth parameters and total soluble protein (TSP) contents declined with increase in soil salinity level. While, antioxidant enzyme activities (CAT, SOD and POD) were increased with salinity. However, exogenously applied GA3 significantly enhanced the plant growth and TSP in onion seedlings. Interestingly, CAT, SOD and POD concentration decreased with GA3 application which depicts stress alleviation in saline stressed onion plants due to GA3. It was concluded that the growth of onion could be enhanced to some extent by the application of GA3 under salinity stress. [ABSTRACT FROM AUTHOR]

Phytogenic herbal extracts received considerable attention in the broilers industry as friendly alternative substitutes to antibiotics. These additives can be included in the food or drinking water to enhance birds' growth rate and well-being. Hence, the current investigation examined the effect of including Aloe vera gel in drinking water on the growth rate, biochemical blood indices, and broilers' antioxidative capacity. Cobb 500 broiler chicks (n = 120), 1 day old of initial weight = 48.6 ± 1.65 g, were divided into three treatments where the control group was fed the basal diet without including Aloe vera gel in drinking water. The second and third groups were fed the basal diet, and Aloe vera gel was included in drinking water at 1 and 1.5%, respectively. The final body weight, weight gain, daily weight gain, and feed conversion ratio were significantly improved in birds that received drinking water with Aloe vera gel at 1.5% compared to the control and 1% groups (P ≤ 0.05). The kidney (creatinine and urea) and liver (ALT and AST) function indices of broilers that received drinking water with or without Aloe vera gel showed no significant differences with the control group (P ≥ 0.05). The blood total protein and albumin had higher values in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). The total blood cholesterol, triglycerides, and LDL levels were significantly decreased in the group of birds that received 1.5% Aloe vera gel in drinking water (P ≤ 0.05). The HDL level was higher in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). The total antioxidative capacity (TAC) and glutathione peroxidase (GPX) showed higher activity in the group of birds that received 1.5% Aloe vera gel while the level of malondialdehyde (MDA) was lower in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). In summary, including Aloe vera gel in drinking water enhanced the growth rate, biochemical blood indices, and broilers' antioxidative capacity.

Due to climate change in recent years, there has been an increasing water deficit during the winter wheat sowing period. This study evaluated six Croatian winter wheat varieties’ physiological, biochemical, and molecular responses under two drought stress levels at the germination/seedling growth stage. Lipid peroxidation was mainly induced under both drought stress treatments, while the antioxidative response was variety-specific. The most significant role in the antioxidative response had glutathione along with the ascorbate-glutathione pathway. Under drought stress, wheat seedlings responded in proline accumulation that was correlated with the P5CS gene expression. Expression of genes encoding dehydrins (DHN5, WZY2) was highly induced under the drought stress in all varieties, while genes encoding transcription factors were differentially regulated. Expression of DREB1 was upregulated under severe drought stress in most varieties, while the expression of WRKY2 was downregulated or revealed control levels. Different mechanisms were shown to contribute to the drought tolerance in different varieties, which was mainly associated with osmotic adjustment and dehydrins expression. Identifying different mechanisms in drought stress response would advance our understanding of the complex strategies contributing to wheat tolerance to drought in the early growth stage and could contribute to variety selection useful for developing new drought-tolerant varieties.

The positive impact on restoring soil functionality, decreasing toxic elements (TE) bioaccessibility, and enhancing soil physicochemical and biological parameters established a consensus on considering a Miscanthus × giganteus convenient species for phytomanaging wide TE contaminated areas. Nevertheless, information about the plant’s mode of reaction to elevated soil multi-TE concentrations is still scarce. For the sake of investigating the miscanthus response to stressful TE concentrations, an ex-situ pot experiment was initiated for 18 months, with three miscanthus cultivars referred to as B, U, and A planted in soils with gradient Cd, Pb, and Zn concentrations. A non-contaminated control soil was introduced as well, and plants were cultivated within. Results revealed that the long exposure to increasing soil TE concentrations caused the number of tillers per plant to decline and the TE concentrations in the leaves to boost progressively with the soil contamination. The photosynthetic pigments (chlorophyll a, b, and carotenoids) were negatively affected as well. However, the phenolic compounds, flavonoids, tannins, and anthocyanins, along with the antioxidant enzymatic activities of superoxide dismutase, ascorbate peroxidase, and glutathione reductase elevated progressively with the TE concentration and exposure duration. Conclusively, miscanthus plants demonstrated an intensified and synchronized antioxidative activity against the TE concentration.

The natural antioxidants are well known for their antioxidative activity without side effects when compared to antibiotics. Hence, the present study aimed at evaluating p-Coumaric acid as an antioxidant additive on the blood and mRNA levels of antioxidant-related factors in common carp (Cyprinus carpio). Fish fed the basal diet supplemented with p-Coumaric at 0, 0.5, 1, and 1.5 g/kg for 56 days, then the serum, intestine, and liver samples were collected. The growth performance of fish fed with CA showed significantly (P < 0.05) improved FW, WG, and SGR compared to those of the control one. However, the feed conversion ratio was significantly (P < 0.05) reduced in fish fed 1 and 1.5 g/kg diet levels. SOD was not significantly differed among the groups fed with varied p-Coumaric acid (P > 0.05). Serum GPX and TAC were enhanced considerably by p-Coumaric acid regarding the control with the highest being in fish fed 1.5 g/kg diet (P < 0.05). Serum CAT was more elevated in fish provided p-Coumaric acid at 1 or 1.5 g/kg than the control while fish fed 0.5 g/kg did not display significant changes. MDA level significantly decreased by all p-Coumaric acid groups compared to the control one, and the lowest level was observed in 1.5 g/kg (P < 0.05). The mRNA level of CAT was significantly upregulated in the liver by p-Coumaric acid at 1 or 1.5 g/kg (P < 0.05), while the intestine CAT did not influence by p-Coumaric acid (P > 0.05). The measured SOD in the liver and intestine samples revealed no changes in common carp fed p-Coumaric acid (P > 0.05). GPX was significantly upregulated in the intestine by p-Coumaric acid at 1 or 1.5 g/kg (P < 0.05), whereas the liver GPX was upregulated by p-Coumaric acid at 1.5 g/kg. The mRNA level of the GST gene in the intestine of common carp was upregulated by p-Coumaric acid at 1.5 g/kg, whereas the liver displayed upregulated GST in fish fed 1 g/kg diet. The present study approved the application of p-Coumaric acid as a natural antioxidant for friendly, sustainable aquaculture. [ABSTRACT FROM AUTHOR]

The present study was designed to evaluate the effects of ethanolic extracts of Hypericum perforatum (HP), Origanum vulgare (ORG), and Melissa officinalis (MOF) on Nile tilapia (Oreochromis niloticus) juveniles. Fish (16.92 ± 0.28 g) were randomly divided into seven groups fed on diets with 0 % (CTR), and two levels (0.2 % and 0.5 %) from each plant extract for 60 days. Final body weight, weight gain %, specific growth rate, and feed conversion ratio were significantly improved in the groups fed with ORG and MOF at 0.5 % (P < 0.05). Moreover, ORG 0.5 % and MOF 0.5 % groups showed a significant increase in RBCs and WBCs counts as well as the hematocrit and hemoglobin values (P < 0.05). Besides, significant enhancement was noticed in the levels of intestinal digestive enzymes in the MOF 0.5 % group (P < 0.05). Activities of hepatic superoxide dismutase, glutathione peroxidase, catalase were significantly improved, meanwhile, the hepatic malondialdehyde levels were significantly decreased in all groups fed on phytogenic diets compared to the CTR group (P < 0.05). Furthermore, ORG 0.5 % and MOF 0.5 % groups showed a significant increase in serum total protein, and alternative complement activity (ACH50) (P < 0.05). Attractively, serum lysozyme levels were significantly increased while serum endotoxin values decreased in all groups fed on phytogenic diets. Furthermore, the MOF 0.5 % group showed the highest activities of skin mucus lysozyme, ACH50, and protease (P < 0.05), meanwhile mucosal total immunoglobulins were the highest in ORG 0.5 % and both levels of MOF. ORG 0.5 % and MOF 0.5 % groups showed the highest protection levels of fish following challenge with pathogenic Aeromonas hydrophila. Conclusively, this comparative study showed that both ORG and MOF extract at a 0.5 % level can effectively improve the growth, health, and immune status of Nile tilapia juveniles.

The aim of this study was to evaluate physiological responses to short-term heat stress in the leaves of traditional (Bistrica) and modern (Toptaste) plum cultivars. In this study, detached plum leaves were incubated at 25 °C (control) and 40 °C (stress). After 1 h of exposure to heat (40 °C), chlorophyll a fluorescence transients were measured, and several biochemical parameters were analyzed. Elevated temperature caused heat stress in both plum cultivars, seen as a decrease in water content (WT), but in the leaves of the cultivar Bistrica, an accumulation of proline and phenols, as well as an accumulation of photosynthetic pigments, suggest the activation of a significant response to unfavorable conditions. Conversely, in the leaves of Toptaste, a significant accumulation of malondialdehyde (MDA) and an activation of guaiacol peroxidase (GPOD), all together with a decreased soluble proteins content, indicate an inadequate response to maintaining homeostasis in the leaf metabolism. The impact of an elevated temperature on photosynthesis was significant in both plum cultivars as reflected in the decrease in performance indexes (PIABS and PItotal) and the maximum quantum yield of PSII (Fv/Fm), with significantly pronounced changes found in Toptaste. Unlike the traditional plum cultivar, Bistrica, in the modern cultivar, Toptaste, short-term heat stress increased the minimal fluorescence (F0) and absorption (ABS/RC), as well as Chl b in total chlorophylls. Additionally, the inactivation of RCs (RC/ABS) suggests that excitation energy was not trapped efficiently in the electron chain transport, which resulted in stronger dissipation (DI0/RC) and the formation of ROSs. Considering all presented results, it can be presumed that the traditional cultivar Bistrica has better tolerance to heat stress than the modern cultivar Toptaste. The cultivar, Bistrica, can be used as a basis in further plum breeding programs, as a source of tolerance for high temperature stress.

The endemic variety Glycine max (L.) Merr. cv. Namdan is one of the most important crops in the agricultural production in Nghe An province (Vietnam). Experiments were carried out to assess the adaptive capability of that soybean variety in drought condition. The oxidative stress with a burst of O2.- and H2O2 in soybean leaves resulted the obviously cellular membrane damage that was illustrated by a continuous increase in content of products of lipid peroxidation. A high accumulation in activity of enzymatic antioxidants such as SOD, CAT and POX would detoxify the excess of O2.- and H2O2 and decrease oxidative damages. An increase in amino acid proline's content protects the stressed cells by adjusting intercellular osmotic potential. Those results suggested the drought tolerant capability for variety Namdan. [ABSTRACT FROM AUTHOR]

In this study, Nile tilapia fingerlings with average body weight (8.6 ± 0.06 g) were exposed to zinc (Zn) toxicity and tested its amelioration with miswak (Salvadora persica L.) (SP) supplemented diet. Five fish groups were fed on diets with SP at 0, 0.25, 0.5, 1.0, and 2.0% (T1, T2, T3, T4, and T5, respectively) diet without Zn exposure, while another five groups were exposed to Zn at 7 mg/L and co-supplemented with SP at 0, 0.25, 0.5, 1.0, and 2.0 % (T6, T7, T8, T9, and T10, respectively). After 12 weeks, fish-fed 1.0% SP diet (T4) achieved the highest growth and feed performances, while the lowest one was in Zn-exposed fish (T6) (P < 0.05). T6 and T7 groups showed the most inferior carcass protein and ash contents, while T4 and T5 showed the highest lipid content (P < 0.05). The level of Zn residue increased in fish exposed to Zn (P < 0.05). Fish exposed to Zn and fed SP showed high blood urea, catalase, ALT, AST, and total superoxide dismutase (T-SOD), while the malondialdehyde (MDA) was decreased (P < 0.05). Interestingly, miswak resulted in elevated catalase and T-SOD and reduced MDA in fish without Zn exposure (P < 0.05). Zn exposure causes abnormal histopathological characteristics in gills, hepatopancreas, posterior kidney, and musculature tissues of tilapia, while fish-fed SP showed regular, healthy, and protected histopathological characters. The results suggested that SP can induce the antioxidant responses that prepare Nile tilapia for a further suppressive oxidative condition (i.e., Zn exposure). [ABSTRACT FROM AUTHOR]

Chlorpyrifos (CPF) is an insecticide that is commonly applied in the agriculture sector. However, little is known about the protective role of Spirulina platensis (SP) and/or β-glucan (BG) on African catfish exposed to chronic CPF toxicity. The fish (95 ± 5 g, initial weight) were assigned to 5 fiberglass tanks (500 L, 50 fish/tank) where the 1st and 2nd fed the basal diet, while the 3rd, 4th, and 5th fed diets with SP, BG, and SP+BG at 0.5%, respectively. Fish in 2nd, 3rd, 4th, and 5th groups were exposed to CPF at a dose of 1.5 mg/L and fed the respective diets for 60 days. In comparison with the control group, CPF-exposed fish exhibited significantly lower (P ≤ 0.05) body weights, feed intake, red blood cells count, hemoglobin concentration, packed cell volume (PCV) (%), lymphocytes, monocytes, phagocytic activity, and phagocytic index, while feed conversion ratio, white blood cell count, and neutrophils count were significantly increased. Fish exposed to CPF also revealed a significant elevation in aspartate aminotransferase (AST), alanine aminotransferase (ALT), cholesterol, triglycerides, low-density lipoproteins (LDL), very-low-density lipoproteins (vLDL), glucose concentration, urea, and creatinine as well as low total proteins, albumin, globulins, and high-density lipoprotein (HDL) concentration. Fish exposed to CPF also exhibited a high concentration of malondialdehyde while glutathione content, glutathione peroxidase, and catalase activities were significantly decreased in the liver, gills, brain, and intestine tissues. Moreover, exposure to CPF resulted in higher transcription of cytochrome P450 (CYP1A-P450) gene expression than the 1st group. Histopathological investigations revealed various degrees of pathological lesions in different organs like the liver, kidney, brain, spleen, and intestine tissues. Interestingly, dietary SP supplementation either alone or combined with BG significantly ameliorated the alterations mitigated by CPF-induced organ injuries and genotoxicity. Therefore, it could be concluded that SP or/and BG are able to induce the protective consequences on health status, immunity, and antioxidative response of African catfish exposed to CPF. [ABSTRACT FROM AUTHOR]

Water stress accelerates the generation of reactive oxygen species, which trigger a cascade of antioxidative defence mechanisms comprising enzymatic and nonenzymatic antioxidants. The aim of this study was to investigate the oxidative damage and the antioxidative defence systems in seedlings of the water stress-tolerant (B71) and the sensitive (B59) inbred lines of sunflower (Helianthus annuus L.) in response to water stress and rewatering. In addition, we characterised the transcriptomic profile associated with enzymatic antioxidative defence. An elevated electrolyte leakage in B59 indicated increased plasmatic membrane permeability, which correlated with greater sensitivity to water stress. In response to water stress, both lines showed an increase in malondialdehyde and H2O2 content but these increases were more noticeable in the sensitive line. In both lines, an increase in enzymatic activity (e.g. peroxidase and ascorbate peroxidase) was not sufficient to overcome the H2O2 accumulation triggered by water stress. Upon water stress, the overall expression level of genes associated with the enzymatic antioxidant system increased in B71 and decreased in B59, which showed downregulated levels of most genes in the shoots. The general profile of phenolic compounds was clearly different between organs and between inbred lines. The B59 line activated nonenzymatic antioxidant responses to counteract the oxidative stress caused by water stress. The tolerance of B71 to water stress could be associated with compensatory antioxidant mechanisms based on the expression of genes encoding enzyme components of the ascorbate–glutathione and redoxin cycles, which contributed to explaining, at least partly, the response of this line. Water is essential for plant growth and research related to plant responses to water scarcity is important. We tried to understand how sunflower seedlings with different water stress tolerance were able to maintain a particular metabolic or functional state, although they were subject to negative environmental factors such as water stress. Here, the ability of B59 and B71 seedlings to respond to water stress was based on different antioxidant mechanisms comprising the coordinated action of enzymatic and nonenzymatic constituents. [ABSTRACT FROM AUTHOR]

Due to unique physiochemical properties, nanoparticles (NPs) have acquired substantial attention in the field of research. However, threats of ecotoxicity and phytotoxicity have limited their biological applications. In this study in vivo experiments were performed to determine the effect of CuO (12.5, 25 and 50 mg/kg) and ZnO (200, 400 and 600 mg/kg) NPs on growth, and antioxidant activities of Brassica nigra. The results showed that CuO NPs did not affect the seed germination while presence of ZnO NPs in the soil generated an inhibitory effect. Both CuO and ZnO NPs positively influenced the growth of stem and other physiological parameters i.e. stem height increased (23%) at 50 mg/kg CuO while root length decreased (up to 44%) with an increase in the concentration of NPs. Phytochemical screening of apical, middle and basal leaves showed elevated phenolic and flavonoid contents in the range of 15.3–59 μg Gallic Acid Equivalent (GAE)/mg Dry Weight (DW) and 10–35 μg Querceitin Equivalent (QE)/mg DW, respectively, in NPs‐treated plants. Antioxidant activity was higher in CuO NPs‐treated plants as compared to ZnO and control plants. Results conclude that CuO and ZnO NPs at low concentrations can be exploited as nanofertilisers in agriculture fields. [ABSTRACT FROM AUTHOR]

Key message: AgNPs caused significant toxicity and induced oxidative stress in the microalga N. oculata. Also, the interaction between AgNPs and algae led to cell membrane damage. Silver nanoparticles (AgNPs) have been broadly applied in several industrial sectors, and thus inevitably released into the aquatic environments. In the present study, the effect of various concentrations of AgNPs (up to 50 mg/L) on the microalga Nannochloropsis oculata (N. oculata) was investigated. The obtained results showed that half maximal effective concentration (EC50) of AgNPs for the microalga was 20.88 mg/L. Also, the different applied concentrations of AgNPs inhibited the cell growth as well as the photosynthetic machinery and stimulated the production of malondialdehyde (MDA) and hydrogen peroxide (H2O2). AgNP treatments dramatically enhanced the content of carotenoids in the treated algae, while they significantly reduced the quantity of phenolic compounds. Furthermore, AgNPs increased the enzymatic activity of catalase (CAT), ascorbate peroxidase (APX) and lactate dehydrogenase (LDH), while they considerably decreased the activity of polyphenol oxidase (PPO) compared to the control sample. Gas chromatography–mass spectrometry (GC–MS) examination demonstrated that after exposure of N. oculata cells to AgNPs, the amounts of saturated fatty acids (SFAs) and polyunsaturated fatty acids (PUFAs) were raised, while the levels of monounsaturated fatty acids (MUFAs) were lessened. The Fourier transform infrared spectroscopy (FTIR) results and the microscopic images revealed the interaction of AgNPs with the cells of N. oculata. [ABSTRACT FROM AUTHOR]

In the present study, low temperature-dependent physiological changes were investigated through photosynthetic activity and some endogenous mechanisms in two winter oilseed rape cultivars (Brassica napus L. ssp. oleifera cvv. Eurol and Hansen) on the basis of leaf age. Chlorophyll fluorescence measurements demonstrated that low temperature caused decreased photosynthetic activity in both cultivars. However, photosynthetic apparatus in the young leaves of Hansen is more tolerant to low temperature as demonstrated by lower F 0 (minimum fluorescence yield) and 1–qp (excitation pressure of photosystem II), higher F m (maximum fluorescence yield), F v/ F m and non-photochemical quenching (NPQ) compared with Eurol. In addition, young leaves of Hansen represented marked increase in some antioxidant enzyme activities (superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR)) during cold exposure. In the young leaves of Eurol, however, APX and GR activity was decreased by low temperature, indicating lower efficiency of ascorbate-glutathione cycle. Lower antioxidant activity in the young leaves of Eurol may be responsible for increased malondialdehyde (MDA), H2O2 and membrane damage and decreased chlorophyll content as a result of oxidative damage during cold exposure. In the cold-stressed mature leaves, both cultivars represented similar antioxidant capacities and photosynthetic efficiency. As a consequence, coordinated increase in SOD, APX and GR activities, increased capacity to keep quinone A (QA) in an oxidised state (as indicated by lower 1–qp) and accumulation of soluble sugar and proline could be mainly attributed to higher level of tolerance of the young leaves of Hansen to low temperature when compared with Eurol. Cold tolerance in some plant species provides farmers to carry out agricultural activities in wintertime. The responses of winter-type plants to low temperature may represent great variation dependent on the cultivar and developmental manner and our results showed that simultaneous increases in the activities of some antioxidant enzymes led to less oxidative stress and relatively higher photosynthetic activity in the young and mature leaves of Hansen under low temperature. As a result, cultivation of Hansen may provide higher yield. [ABSTRACT FROM AUTHOR]

Aquaculture and fisheries have provided protein sources for human consumption for a long time, but diseases have induced declines in product benefits and raised concerns, resulting in great losses to these industries in many countries. The overuse of antibiotics for the treatment of diseases has increased the chemical concentrations in culture systems and weakened the natural immunity of aquatic organisms. Concerns regarding the detrimental effects of antibiotics on the environment and human health due to residual antibiotic-related issues encourage the development of reliable, environmental and health safety methods, such as vaccines, probiotics, prebiotics, synbiotics and phytobiotics, for protection against disease and for reducing and possibly eliminating disease occurrence. Immunity has been effectively enhanced by pro-, pre-, and synbiotics, which confer strong protection and reduce the risks associated with stressors and disease outbreaks in culture systems. These agents confer several benefits, including enhancing both host growth and immune responses against pathogens, while sustaining health and environmental stability, and their use is thus widely accepted. Alterations in gene expression in individual cells could serve as an indicator of the immunity and growth rate of aquatic animals after pro-, pre- and synbiotic feeding. This review addresses the potential use of pro, pre- and synbiotics as immunostimulants for improved aquaculture management and environmental health and chronicles the recent insights regarding the application of pro-, pre- and synbiotics with special emphasis on their immunomodulatory and antioxidative responses based on gene expression changes. Furthermore, the current review describes the research gaps and other issues that merit further investigation. Image 1 • This review highlights prebiotic, probiotic, and synbiotics as a key factor for sustainable aquaculture. • The use of such additives resulted in upregulated transcription of immune and antioxidant related genes. • The immune related genes affected by pro-, pre-, and synbiotics will further increase the understanding of its role in aquatic animals. [ABSTRACT FROM AUTHOR]

Celery (Appium graveolens L.) and parsley (Petroselinum crispum (Mill.) Fuss) are herbs utilized in the everyday diet as spices and culinary flavorings, often used in the chemical and medicinal industries. Despite the knowing benefits of different plants from the Apiaceae family, their chemical composition is closely associated with various extrinsic factors. Environmental loading with trace elements (TEs) can modify a plant’s metabolic pathways, change bioactive compounds production, cause plant pollution, and consequently provoke human health issues. Therefore, we established this research aiming to unravel the linkage between TEs accumulation and phenolic status in celery and parsley. Higher As, Cd, and Ni levels were observed in celery, which was followed by greater DPPH∙ radical scavenging activity and higher coumarins content. Contrary, parsley accumulated chromium to a greater extent, was richer in flavonoids, apigenin, and its glucosides. No significant difference between species was found in total phenolic contents, where ferulic and chlorogenic acid dominated in both species. A direct relationship between TEs and selected secondary metabolites was proven by the standardized major axis model. Besides abundant bioactive compounds, analyzed plant species showed a moderate hazard index in the children population, since the hazard index was higher than 1. Therefore, future perspectives should be turned towards the production of genotypes with a lower potential for toxic elements accumulation, so the health benefits of plant food will be more prominent.

Abstract The aim of this study was to investigate the potential of a grape seed byproduct to mitigate the harmful damage produced by aflatoxin B1 (AFB1) at systemic level in plasma and liver as well as at local level in the gastrointestinal tract in weaned piglets. Twenty four crossbred pigs (TOPIG) were randomly assigned to one of four experimental diets: 1)- control diet (normal compound feed for starter piglets without mycotoxin), 2)- AFB1 diet (compound feed contaminated with 320 ppb pure AFB1), 3)- GS diet (compound feed including 8% of grape seed meal), 4)- AFB1+GS diet (compound feed containing 8% of grape seed meal contaminated with 320 ppb AFB1) for 30 days. The results showed that pigs fed AFB1 diet had altered performance (−25.1%), increased the thiobarbituric substances (TBARS) concentration wile reduced total antioxidant capacity and activity of antioxidant enzymes (CAT, SOD and GPx) in plasma and organs. AFB1 produced a dual effect on inflammatory response by increasing the level of pro-inflammatory cytokines in liver and colon and decreasing these cytokines in duodenum. The inclusion of grape seed in the diet of AFB1 intoxicated pigs enhanced the antioxidant enzymes activity, decreased the pro-inflammatory cytokines and TBARS level and ameliorated the growth performance of AFB1-treated animals. These findings suggest that grape waste is a promising feed source in counteracting the harmful effect of aflatoxin B1. Highlights • Growth and inflammatory indices as well as antioxidant status decreased in weaned pigs exposed to 320 ppb of AFB1. • Dietary grape seed waste restored the pro-inflammatory cytokines level and body weight of pigs fed AFB1 contaminated diet. • The inclusion of grape seed in the diet of AFB1 intoxicated pigs ameliorated the phase-I antioxidant enzymes activity. • Grape waste is a promising feeding source for counteracting the harmful effect of AFB1. [ABSTRACT FROM AUTHOR]

Drought and nitrogen availability are two important environmental factors that affect plant growth and the global distribution of plants. We examined the effect of nitrogen on PSII in the leaves of maize seedlings under drought stress using three nitrogen concentrations (0.5, 7.5 and 15 mM) and three levels of water availability (normal conditions, mild drought and severe drought). Shoot fresh and dry weights and root fresh weight decreased with increasing drought conditions. In maize leaves subjected to drought stress, the chlorophyll a (Chl a) and chlorophyll b (Chl b) contents, net photosynthetic rate, transpiration rate, stomatal conductance, maximum chemical efficiency (F v/ F m), and photochemical efficiency of PSII (ΦPSII) were significantly reduced. Moderate nitrogen supply relieved the drought stress and enhanced the photosynthetic capacity. Malondialdehyde, H2O2 and O2−• accumulated in maize leaves under drought stress. Superoxide dismutase and ascorbate peroxidase activities increased in maize leaves under mild drought stress, but were significantly reduced under severe drought stress. The NO3− content and nitrate reductase (NR) activity of maize leaves were significantly reduced under drought stress, while moderate nitrogen supply promoted the accumulation of NO3− and an increase in the nitrate reductase activity. The abscisic acid content increased significantly; this increase was positively correlated with the nitrogen concentration under drought stress. Together, these results indicate that moderate nitrogen supply increases plant resistance to drought stress, while high or low nitrogen concentrations increase the sensitivity of maize to drought stress. These findings are important for guiding the agricultural use of nitrogen fertilisers. Drought and nitrogen availability are two important environmental factors that affect plant growth and global distribution of plants. We examined the effect of nitrogen on physiological characters of maize seedlings under drought stress and find that moderate nitrogen supply increases plant resistance to drought stress. These findings are important for guiding the agricultural use of nitrogen fertilisers. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (NPs) are the third highest in terms of global production among the various inorganic nanoparticles, and there are concerns because of their worldwide availability and accumulation in the environment. In contrast, zinc is an essential element in plant growth and metabolism, and ZnO NPs (nano-ZnO) may have unknown interactions with plants due to their small sizes as well as their particular chemical and physical characteristics. The present study examined the effect of nano-ZnO (25 nm) and bulk or natural form (<1000 nm, bulk-ZnO), compared with zinc in the ionic form (ZnSO4) on Nicotiana tabacum seedlings in a nutrient solution supplemented with either nano-ZnO, bulk-ZnO (0.2, 1, 5 and 25 µM) or ZnSO4 (control) for 21 days. Results showed that nano-ZnO at most of the levels and 1 µM bulk-ZnO positively affected growth (root and shoot length/dry weight), leaf surface area and its metabolites (auxin, phenolic compounds, flavonoids), leaf enzymatic activities (CAT, APX, SOD, POX, GPX, PPO and PAL) and anatomical properties (root, stem, cortex and central cylinder diameters), while bulk-ZnO caused decreases at other levels. The activities of enzymes were induced to a greater extent by intermediate nano-ZnO levels than by extreme concentrations, and were higher in nano-ZnO treated than in bulk treated tobacco. As the ZnO level increased, the vascular expansion and cell wall thickening of the collenchyma/parenchyma cells occurred, which was more pronounced when treated by NPs than by its counterpart. The Zn content of root and leaf increased in most of ZnO treatments, whereas the Fe content of leaves decreased. Our findings indicate that tobacco responded positively to 1 µM bulk-ZnO and to nearly all nano-ZnO levels (with the best levels being at 0.2 µM and 1 µM) by morphological, physiological and anatomical adjustments. Hydroponic systems could be a reliable, versatile and sensitive method to investigate the plant responses to the nanoparticle exposure. As ZnO nanoparticles (NPs) and bulk forms possess unique physicochemical characteristics, they are globally used in different industries and may influence plant growth in the environment. As an extensive investigation of the effect of both ZnO NPs and bulk form ZnO on various morphological, physiological and anatomical features of tobacco plants, the present study pinpoints the responses compatible with ZnO-induced stress. [ABSTRACT FROM AUTHOR]

Araucaria angustifolia (Bert.) O. Kuntze is a species critically endangered of extinction and its development and propagation is strongly affected by abiotic stress. We have previously shown the activation of uncoupling protein in A. angustifolia embryogenic stem cells subjected to cold stress. Now, we have furthered those studies by exposing these cells to cold stress (4 ± 1 °C for either 24 or 48 h) and evaluating parameters associated with oxidative stress and alterations in the cellular and mitochondrial responses. Cold stress affect the H2O2 levels and lipid peroxidation increased after both stress condition, an effect associated with the decrease in the activities of peroxidases, catalase and ascorbate/dehydroascorbate ratio. On the other hand, the activities of ascorbate peroxidase, monodehydroascorbate and dehydroascorbate reductases increased as an indication of adaptation. Another important impact of cold stress conditions was the decrease of external alternative NAD(P)H dehydrogenases activity and the increase of mitochondrial mass. These results show that cold stress induces oxidative stress in A. angustifolia embryogenic cells, which results in activation of the glutathione-ascorbate cycle as a compensation for the decrease in the activities of catalase, peroxidases, and external NAD(P)H dehydrogenases. Our results contribute to the understanding of the pathways that gymnosperms employ to overcome oxidative stress, which must be explored in order to improve the methods of conservation and propagation of A. angustifolia. [ABSTRACT FROM AUTHOR]

Salinity stress usually causes a serious yield reduction in crop production. Silicon (Si) has been reported to be able to alleviate stress damage, but the mechanism is still unclear. The aim of this work was to study the effect of exogenous silicon (Si) on the young maize plants welfare. For that the activities of major antioxidant enzymes (superoxide dismutase, SOD; peroxidases, POX; ascorbate peroxidase, APX) and on the lipid peroxidation (content of malondialdehyde, MDA) were investigated in the roots of salt-stressed maize (Zea mays L.). Two maize hybrids (Novania and Almansa) contrasting in their response to NaCl were tested. Four treatments with three replicates were monitored: control (without Si and NaCl), 2.5 mM Si, 150 mM NaCl, 150 mM NaCl and 2.5 mM Si. Maize roots were harvested 10 days after the treatment. MDA, ascorbate content and enzyme activities were assayed spectrophotometrically. The isoenzyme pattern of the antioxidant enzymes was detected by native PAGE. Compared with the plants treated with salt alone, added Si significantly increased MDA content in hybrid Almansa, while in Novania no increase was observed. The addition of Si significantly enhanced the activities of SOD in salt-stressed plants in both hybrids. The activities of POX and APX in salt stressed roots were significantly increased in Almansa hybrid in the presence of Si. The isoenzyme pattern followed changes in the activity of SOD; however in POX and APX such a tendency was not registered. The changes of the intensity and in the case of POX also the number of bands were detected. From these results we conclude, that Si addition fortified enzymatic antioxidative response operates in roots of young maize plants by a still unknown mechanism. The approval effect of Si is evident in the case of the SOD detoxifying system regardless of the hybrid, and for the POX family in the more sensitive maize hybrid Almansa. The presented outputs point out that silicon may protect plant tissues from oxidative damage under salt stress. Since the alleviative effect seems to be hybrid-specific, silicon alleviation of salt stress is probably not a universal feature in general and should be carefully considered between plants and/or hybrids. [ABSTRACT FROM AUTHOR]

Herbs of the Labiatae have relatively low salt tolerance. They are widely grown in drylands, but salt stress there is a typical problem and may reduce yields. To examine their salt tolerance mechanisms, we grew basil, sage, thyme, and oregano in nutrient solution containing 50 mM NaCl and determined the biomass; contents of Na, K, and Mg in leaf blades, stems, and roots; contents of total chlorophyll, malondialdehyde (MDA), hydrogen peroxide in leaf blades; and activities of antioxidative enzymes in leaf blades. The salt tolerance decreased in the order of basil ≈ sage > thyme > oregano. The good salt tolerance of basil was explained by a significant increase in the activity of catalase, in addition to the low Na/K ratio of leaf blades due to the retention of Na in stems and roots and of K in leaf blades. The good salt tolerance of sage was explained by the low Na/K ratio in leaf blades and the prevention of lipid peroxidation by high antioxidative enzyme activities, despite its poorer management of nutrient uptake. In thyme, although catalase activity increased significantly to alleviate salt-induced oxidative stress caused by Na influx into all parts, low K and Mg allowed shoot weight in particular to decrease. In oregano, antioxidative responses appeared as significant increases in ascorbate peroxidase and glutathione reductase activity, and K was accumulated in leaf blades, but serious salt-induced oxidative stress caused by high Na influx into all parts reduced the growth of all parts. These results show that despite similar responses among species, salt tolerance is not necessarily the same. In this experiment, we revealed the salt tolerance mechanism of each of four Labiatae herbs by revealing their strengths and weaknesses in nutrient uptake and antioxidative responses. [ABSTRACT FROM AUTHOR]

Salt stress is one of most dramatic abiotic stresses, reduces crop yield significantly. Application of hormones proved effective salt stress ameliorating approach. 24-Epibrassinolide (EBL), an active by-product from brassinolide biosynthesis shows significant salt stress tolerance in plants. EBL application improves plant growth and development under salt stress by playing as signalling compound in different metabolic and physiological processes. This article compiles all identified ways by which EBL improves plant growth and enhances crop yield. Furthermore, EBL enhances photosynthetic rate, reduces ROS production and plays important role in ionic homeostasis. Furthermore EBL-induced salt stress tolerance suggest that complex transcriptional and translational reprogramming occurs in response to EBL and salt stress therefore transcriptional and translational changes in response to EBL application are also discussed in this article. [ABSTRACT FROM AUTHOR]

Spatial distribution of potentially toxic metals (PTMs) and their accumulation in mangrove Avicennia officinalis L. were studied along 8 locations in and around Sundarban mangrove wetland, India. Among 8 locations, S3 (Chemaguri) and S5 (Ghushighata) showed higher concentration of PTMs (Cd, Cr, Cu, Ni, Pb, Zn) characterized by higher enrichment factors (3.45–10.03), geo-accumulation indices (0.04–1.22), contamination factors (1.14–3.51) and pollution load indices (1.3–1.45) indicating progressive deterioration of estuarine quality and considerable ecotoxicological risk. Metal concentration in A . officinalis leaves showed significant correlation with sediment metals implying elevated level of bioaccumulation. Significant statistical correlation between photosynthetic pigments (Chlorophyll a, Chlorophyll b), antioxidant response (free radical scavenging and reducing ability) and stress enzymatic activity (Peroxidase, Catalase, Super-oxide dismutase) of A . officinalis with increasing metal concentration in the contaminated locations reflects active detoxification mechanism of the plant. The study indicates the potentiality of biomonitoring metal pollution using studied biochemical markers in mangrove habitats. [ABSTRACT FROM AUTHOR]

Purpose: Ionizing radiation (IR) can act on atomic structures, producing damage to biomolecules. Earlier investigations evaluating individual radiosensitivity in vitro were focused on cytogenetic biomarkers (chromosomal aberrations - CA and micronuclei - MN). Since IR can also cause oxidative damage by producing reactive oxygen species, the main goal of this investigation was to establish the influence of redox status on CA and MN frequency in human peripheral blood lymphocytes. Materials and methods: Blood samples from 56 healthy donors were irradiated at doses of 0, 0.75, 1.5 and 3 Gy and then analyzed cytogenetically and biochemically. Results: The results showed inter-individual variability in all analyzed parameters, as well as dose-dependent increases in almost all of them. Correlation analysis indicated no association between CA, MN and oxidative stress parameters. However, findings for overall response (HRR) parameters showed that donors with lower values for parameters of antioxidant status had increased levels of cytogenetic damage and higher responses to irradiation and vice versa. Conclusion: Besides well-established cytogenetic biomarkers of radiation exposure, our results indicated promising future use for biochemical oxidative status parameters in routine radiation protection practice, since together they can provide a complete radiation response profile in cases of continuous low-dose exposure, as well as in a radiation emergency. [ABSTRACT FROM AUTHOR]

Co-60 radiation has been broadly used for pest management because it results in male sterility and a lack of emergence of unparasitized hosts due to oxidative damage. Insect life is significantly affected by abiotic stress factors, including Co-60 radiation. In the present study, we determined the influence of Co-60 radiation on an important pest in southern China, the oriental fruit fly Bactrocera dorsalis (Diptera: Tephritidae). We exposed 30-h-old B . dorsalis eggs to Co-60 radiation at doses of (0, 5, 10, 15, 20, 25, 30, 35, and 40 Gy) and determined the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX). CAT and POX activity significantly increased in B . dorsalis in the 1st larvae instar after high-intensity radiation doses (25–40 Gy) and played an important role in the antioxidant response to intensive radiation. The activity of POX in B . dorsalis at the 2nd larval instar sharply decreased after different doses of radiation, except for 10 and 40 Gy. Our results demonstrated that Co-60 radiation affected the activity of antioxidant enzymes and disturbed the physiology of B . dorsalis , especially at early stages (the 1st, 2nd larvae instar). These three antioxidant defense enzymes cooperatively play an important role in protecting B . dorsalis from oxidative damage. [ABSTRACT FROM AUTHOR]

The beneficial effects of N -decanoyl-homoserine lactone (C 10 -HSL), one of the typical N -acyl-homoserine lactones on biological nitrogen removal (BNR) system to resist the acute exposure of zinc oxide nanoparticles (ZnO NPs) has attracted extensive attentions. Nevertheless, the potential impact of dissolved oxygen (DO) concentration on the regulatory capacity of C 10 -HSL in the BNR system has yet to be investigated. This study conducted a systematic investigation of the impact of DO concentration on the C 10 -HSL-regulated BNR system against short-term ZnO NP exposure. Based on the findings, sufficient DO played a crucial role to improve the BNR system's resistance capacity to ZnO NPs. Under the micro-aerobic condition (0.5 mg/L DO), the BNR system was more sensitive to ZnO NPs. The ZnO NPs induced increased intracellular reactive oxygen species (ROS) accumulation, reduced antioxidant enzyme activities, and decreased specific ammonia oxidation rates in the BNR system. Furthermore, the exogenous C 10 -HSL had a positive effect on the BNR system's resistance to ZnO NP-induced stress, primarily by decreasing ZnO NPs-induced ROS generation and improving ammonia monooxygenase activities, especially under low DO concentrations. The findings contributed to the theoretical foundation for regulation strategy development of wastewater treatment plants under NP shock threat. [Display omitted] • BNR was more sensitive to ZnO NPs in micro-aerobic conditions. • High DO level benefited the BNR system's resistance capacity to ZnO NPs' stress. • C 10 -HSL improved the ZnO NP-stressed BNR systems' ammonia oxidation performance. • C 10 -HSL and DO benefited AMO activity and reduced ROS/EPS in BNR system. [ABSTRACT FROM AUTHOR]

Dissolved oxygen (DO) is crucial for the survival of Chinese mitten crab (Eirocheir sinensis); low DO levels adversely affect the health of these crabs. In this study, we evaluated the underlying response mechanism of E. sinensis to acute hypoxic stress by analyzing antioxidant parameters, glycolytic indicators, and hypoxia signaling factors. The crabs were exposed to hypoxia for 0, 3, 6, 12, and 24 h and reoxygenated for 1, 3, 6, 12, and 24 h. The hepatopancreas, muscle, gill, and hemolymph were sampled at different exposure times to detect the biochemical parameters and gene expression. The results showed that the activity of catalase, antioxidants, and malondialdehyde in tissues significantly increased under acute hypoxia and gradually decreased during the reoxygenation phase. Under acute hypoxic stress, glycolysis indices, including hexokinase (HK), phosphofructokinase, pyruvate kinase (PK), pyruvic acid (PA), lactate dehydrogenase (LDH), lactic acid (LA), succinate dehydrogenase (SDH), glucose, and glycogen in the hepatopancreas, hemolymph, and gills increased to varying degrees but recovered to the control levels after reoxygenation. Gene expression data showed that hypoxia signaling pathway-related genes, including hypoxia-inducible factor-1α/β (HIF1α/β), prolyl hydroxylase (PHD), factor inhibiting hypoxia-inducible factor (FIH), and glycolysis-related factors (HK and PK) were upregulated, showing that the HIF signaling pathway was activated under hypoxic conditions. In conclusion, acute hypoxic exposure activated the antioxidant defense system, glycolysis, and HIF pathway to respond to adverse conditions. These data contribute to elucidating the defense and adaptive mechanisms of crustaceans to acute hypoxic stress and reoxygenation. • Acute hypoxia can activate the antioxidant defense system of juvenile E. sinensis with tissue specificity. • Acute hypoxia can increase glycolysis indices, and recover to the control levels after reoxygenation. • Acute hypoxia activates hypoxic signaling pathways to protect against hypoxia through feedback mechanisms. [ABSTRACT FROM AUTHOR]

Microcystis blooms have become a ubiquitous phenomenon in freshwater ecosystems, and the size of Microcystis colonies varies widely throughout the year. In the present study, hydrogen peroxide (H2O2) was applied to test the effect of this algaecide on Microcystis colonies of different sizes and to evaluate the colonies' antioxidant strategy. The results showed that Microcystis populations collapsed under treatment with 5 mg/L H2O2 at colony sizes smaller than 25 µm. A dosage of 20 mg/L H2O2 was necessary to efficiently control Microcystis colonies larger than 25 µm. The enzymatic and non-enzymatic antioxidant systems of different colonies exhibited various strategies to mitigate oxidative stress. In small colonies, superoxide dismutase (SOD) activity was readily stimulated and operated with catalase (CAT) activity to eliminate reactive oxygen species (ROS). In colonies larger than 25 µm, the antioxidant enzyme CAT and antioxidant substance glutathione (GSH) played major roles in mitigating oxidative stress at H2O2 concentrations below 20 mg/L. In addition, application of the algaecide led to the release of intracellular-microcystins (MCs), and oxidatively-driven MCs reached high concentrations when colony size was larger than 100 µm. Algaecide control measures should be implemented before the formation of large colonies to limit the algaecide dosage and MC release. [ABSTRACT FROM AUTHOR]