Recent climate changes worldwide have negatively impacted crop yields, highlighting the urgent need to develop new cultivation strategies to counteract this phenomenon. Our study aimed to analyze the effects of saline (0 mM, 100 mM, 200 mM, and 300 mM NaCl) and heat stress (24 degrees C and 32 degrees C) on the physiological parameters of Chenopodium quinoa variety "Regalona," evaluating the efficacy of the microalgal biostimulant Chlorella vulgaris-like extract (0%, 0.025% and 0.05%). Sprouts grown under these different conditions were assessed for antioxidant content, antioxidant activity, reactive oxygen species, and photosynthetic pigments. The analyses did not reveal significant effects of the two microalgal concentrations on germination percentage or sprout length across the various temperature and salinity conditions. However, antioxidant activity was increased in many experimental trials, especially when the microalgae were combined with salt stress, with the higher biostimulant concentration showing more pronounced effects. Conversely, a temperature of 32 degrees C negatively impacted the parameters measured. These findings provide a basis for further research aimed at enhancing the antioxidant and nutraceutical properties of plants valuable for human nutrition.
In this study, the growth of tomatoes, basil, lettuce and courgette in aeroponic versus traditional soil-based cultivation revealed key differences in mineral nutrient content, antioxidant molecules, and antioxidant activity. The aeroponic system yielded comparable or higher concentrations of P (in basil), K (in lettuce and basil), Ca and Mg (in all species), Fe (in tomatoes), Mn (in basil, courgette and tomatoes), and Cu and Zn (in courgette). Aeroponic cultivation enhanced or maintained the antioxidant content, with the highest flavonoid levels in basil (75.84 mg QE g−1 DW), followed by lettuce (65.97 mg QE g−1 DW). Consistent with these findings, total antioxidant activity assays were highest in aeroponically grown basil (91.27 ARA%). However, responses varied by crop and maturity stage: DPPH radical-scavenging activity was greater in soil-grown lettuce (92.30 ARA%), while FRAP values were highest in basil in both aeroponic and soil-grown cultures (197.02 and 195.3 mg FeSO4 g−1 DW, respectively). However, the interspecific differences indicate that aeroponic systems cannot be applied uniformly; rather, each species could maximize productivity and quality under appropriate conditions. Overall, aeroponic cultivation proved to be a resource-efficient and sustainable alternative to conventional soil farming, providing comparable or superior nutritional quality and reducing water consumption.
Although plastic threatens terrestrial ecosystems, the effects of micro- and nanoplastics (MNPs) combination in plants remain poorly understood and need in-depth investigations. This study investigates the effects of polyethylene MNPs (0.1% w/v; Ø 200-9900 nm) on Ocimum basilicum by exposing seeds to MNPs for 5 days (Seed Treatment; ST) or hydroponically-grown 20-day seedlings for 15 days (Plant Treatment; PT). Biometric, physiological, cytological, ultrastructural responses, oxidative stress level and antioxidant responses were analyzed. In PT, transmission electron microscopy revealed MNPs presence in xylem vessel of stem, highlighting the translocation of smaller particles to aerial parts. MNPs adsorption onto roots reduced water uptake, affecting plant metabolism. ST impaired root growth, with signs of cyto-genotoxicity and oxidative damage. PT reduced CO₂ assimilation due to stomatal limitations and altered plants biometric traits, including root length (+42.6%), root biomass (-35.2%) and leaf area. Oxidative stress increased in leaves in terms of H2O2 accumulation (+47.4%) and lipid peroxidation (+22.2%). These findings underscore the detrimental impact of MNPs on basil growth. Further research is essential to elucidate MNPs uptake and translocation mechanisms, and to assess the potential risks of MNPs contamination for plant health and ecosystem integrity.
Chenopodium quinoa Willd. is a halophytic plant valued for its nutritional and nutraceutical properties, as well as its adaptability to diverse soil and climatic conditions. Biostimulant application enhances plant quality and resilience under adverse environmental conditions. The effects of microalgae extracts (Ettlia pseudoalveolaris and Chlorella vulgaris) and salt stress (NaCl 100, 200, 300 mM) were evaluated on 7-day-old seedlings of two quinoa varieties, ‘Tunkahuan’ and ‘Regalona’. The analysis focused on the content of antioxidant molecules (total phenolics and flavonoids), total antioxidant capacity (measured by DPPH, 2,2-Diphenyl-1-picrylhydrazyl, and FRAP, Ferric Reducing Antioxidant Power, assays), reactive oxygen species (ROS), the levels of lutein, β-carotene, chlorophyll a and b. Microalgae extracts and salt stress treatments significantly increased antioxidant molecules in both quinoa varieties. The highest antioxidant activity, measured by the DPPH assay, was observed in ‘Regalona’, while a dose-dependent increase in antioxidant capacity, by the FRAP assay, was evident in ‘Tunkahuan’ treated with Ettlia. ROS level was reduced by Ettlia in ‘Tunkahuan’ but not in ‘Regalona’. Pigment content increased with higher salt concentrations but decreased with the addition of biostimulants. These findings suggest that the application of microalgae extracts enhances bioactive compounds, improving salinity resistance and increasing the nutraceutical value of quinoa sprouts.
The application of graphene-related materials (GRMs) has increased considerably in various fields, posing a potential environmental risk. However, little is known about sex-related responses to GRMs in dioecious woody plants and in that regard, callus culture represents a reliable tool for toxicity and tolerance studies. In this work, the effects of different concentrations of graphene oxide (GO) and graphene nanoplatelets (GNP) on physiological traits of male and female clones of Populus nigra were investigated. After a 3-week treatment, at high concentrations, GO promoted in female calli, an increase in fresh weight and a reduction in protein content, accompanied by a remarkable enhancement of APX and CAT activity while no toxic effect was observed under GNP treatment. Instead, male cells displayed a greater sensitivity at lower GO concentration (25 mg/L), exhibiting a notable reduction in biomass, nutrient uptake and protein content, associated to an increase in APX and CAT activity. Similarly, at 25 mg/L, GNP caused a slight enhancement in lipid peroxidation (MDA) level and a significant decrease in protein content, accompanied by an increase in the production of flavonoids. These findings revealed sexually different responses to GO and GNP, with female clone exhibiting more tolerance compared to male one.
Polystyrene nanoplastics and titanium dioxide nanoparticles are widely spread in all environments, often coexisting within identical frameworks. Both these contaminants can induce negative effects on cell and plant physiology, giving concerns on their possible interaction which could increase each other’s harmful effects on plants. Despite the urgency of this issue, there is very little literature addressing it. To evaluate the potential risk of this co-contamination, lentil seeds were treated for five days with polystyrene nanoplastics and titanium dioxide nanoparticles (anatase crystalline form), alone and in co-presence. Cytological analyses, and histochemical and biochemical evaluation of oxidative stress were carried out on isolated shoots and roots. TEM analysis seemed to indicate the absence of physical/chemical interactions between the two nanomaterials. Seedlings under cotreatment showed the greatest cytotoxic and genotoxic effects and high levels of oxidative stress markers associated with growth inhibition. Even if biochemical data did not evidence significant differences between materials treated with polystyrene nanoplastics alone or in co-presence with titanium dioxide nanoparticles, histochemical analysis highlighted a different pattern of oxidative markers, suggesting a synergistic effect by the two nanomaterials. In accordance, the fluorescence signal linked to nanoplastics in root and shoot was higher under cotreatment, perhaps due to the well-known ability of titanium dioxide nanoparticles to induce root tissue damage, in this way facilitating the uptake and translocation of polystyrene nanoplastics into the plant body. In the antioxidant machinery, peroxidase activity showed a significant increase in treated roots, in particular under cotreatment, probably more associated with stress-induced lignin synthesis than with hydrogen peroxide detoxification. Present results clearly indicate the worsening by metal nanoparticles of the negative effects of nanoplastics on plants, underlining the importance of research considering the impact of cotreatments with different nanomaterials, which may better reflect the complex environmental conditions.
Beer and its components show potential for reducing hepatic steatosis in rodent models through multiple mechanisms. This study aimed to evaluate beer’s anti-steatotic effects in a high-fat diet (HFD)-induced mouse model of Metabolic dysfunction-Associated Liver Disease (MASLD) and to explore the underlying mechanisms. In the HFD group, steatosis was confirmed by altered blood parameters, weight gain, elevated liver lipid content, and histological changes. These markers were normalized in the HFD+beer group, reaching levels similar to the control (CTR) group. Protein carbonylation and lipid peroxidation levels were consistent across all groups, suggesting that the model represents an early stage of MASLD without oxidative stress. Transcriptomic and CpG methylation analyses revealed clear distinctions between the CTR and HFD groups. RNA sequencing identified 162 differentially expressed genes (DEGs) between the CTR and HFD groups, primarily related to inflammation and lipid regulation. Beer consumption modified the health of the HFD mice, affecting inflammation but not lipid homeostasis (CTR vs. HFD+beer, DEGs = 43). The CpG methylation analysis indicated that beer lowered methylation, impacting genes linked to lipid accumulation and inflammation. A cecal metabolite analysis suggested that beer improved short-chain fatty acid metabolism (SCFA). In summary, a moderate beer intake may mitigate MASLD by modulating lipid metabolism and SCFA pathways, likely through polyphenol activity.
The study of different processing techniques, such as sprouting, cooking and fermentation, can help to develop new products for human health. In this work, raw, cooked and fermented seeds and germinated seeds of Chenopodium quinoa Willd. var. Tunkahuan and Amaranthus caudatus L. var. Alegrìa were compared for the content of antioxidant molecules, total antioxidant capacity and mineral elements. Fermentation was induced spontaneously, with the yeast Saccharomyces cerevisiae, with the bacterium Lactobacillus plantarum and with both microorganisms, for 24 and 48 h. The increase in antioxidant molecules and antioxidant activity was induced by germination, by 24 h of spontaneous fermentation (polyphenols and flavonoids) and by 24 h of L. plantarum fermentation (total antioxidant activity) for both species. Germinated seeds of the two plants showed higher values in respect to seeds of macroelements and microelements. No genotoxic but rather protective effects were determined for seed and germinated seed extracts using the D7 strain of S. cerevisiae, a good tool for the evaluation of protection from oxidative damage induced by radical oxygen species (ROS) in cells and tissues. Therefore, the two varieties could be very suitable for their use in human diet and in supplements, especially as germinated seeds or as fermented foods.
Halophytic plants growing in extreme environments have developed morphological, anatomical, biochemical and physiological adaptations. In this research, the effect of salinity (up to 500 mM NaCl) on the germination parameters and the antioxidant responses of two halophytic Limonium species was evaluated. Seed germination parameters (rate, speed), ROS production and the contents of phenolic compounds and antioxidant enzymes of Limonium delicatulum and Limonium vulgare were investigated, with respect to their tolerance to salt treatments and their ability to recover from salt stress conditions. L. vulgare seeds were less affected by salt treatments than L. delicatulum, and consequently recovered more rapidly full germination. Moreover, L. vulgare seedlings had more antioxidant phenolics and enzyme activities than L. delicatulum. The highest ability of L. vulgare to recover from salt treatment might be the result of its adaptation to a highly stressful environment constituted by inland salty soil, whereas L. delicatulum grows closer to the sea, thus receiving diluted salt spray. This distinction makes L. vulgare a good candidate for biosaline agriculture as edible crop plant.
Halophyte species represent valuable reservoirs of natural antioxidants, and, among these, Salicornia europaea stands out as a promising edible plant. In this study, young and old S. europaea leaves were compared for the content of bioactive compounds and antioxidant activity to assess changes in different growth phases; then, the potential protective effects against low-dose CCl4-induced toxicant-associated fatty liver disease (TAFLD) were investigated by administering an aqueous suspension of young leaves to rats daily for two weeks. Quantification of total and individual phenolic compounds and in vitro antioxidant activity assays (DPPH, FRAP, and ORAC) showed the highest values in young leaves compared to mature ones. Salicornia treatment mitigated CCl4-induced hepatic oxidative stress, reducing lipid peroxidation and protein carbonyl levels, and preserving the decrease in glutathione levels. Electronic paramagnetic resonance (EPR) spectroscopy confirmed these results in the liver and evidenced free radicals increase prevention in the brain. Salicornia treatment also attenuated enzymatic disruptions in the liver’s drug metabolizing system and Nrf2-dependent antioxidant enzymes. Furthermore, histopathological examination revealed reduced hepatic lipid accumulation and inflammation. Overall, this study highlights Salicornia’s potential as a source of bioactive compounds with effective hepatoprotective properties capable to prevent TAFLD.
Quinoa (Chenopodium quinoa Willd.) is a plant of South American origin recently valorized for its nutritional and nutraceutical properties in human diet. Quinoa is cultivated in many parts of the world, with a selection of varieties with good adaptability to extreme climatic conditions and salt stress. The variety Red Faro, native to southern Chile but harvested in Tunisia, was considered for salt stress resistance, considering its seed germination and 10-day seedling growth at increasing doses of NaCl (0, 100, 200 and 300 mM). Seedlings were spectrophotometrically analyzed for antioxidant secondary metabolites (polyphenols, flavonoids, flavonols and anthocyanins), antioxidant capacity (ORAC, oxygen radical absorbance capacity, DPPH*, 2,2-diphenyl-1-pic-rylhydrazyl), antioxidant enzyme activity (superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) and catalase (CAT)) and mineral nutrient content in root and shoot tissues. Cytogenetic analysis of root tip was performed to check for meristematic activity and the possible presence of chromosomal abnormalities induced by salt stress. The results indicated a general increase in antioxidant molecules and antioxidant enzymes NaCl dose-dependent, no effects on seed germination but negative effects on seedling growth, and little effect on root meristems mitotic activity. These results indicated that stress conditions can induce an increase in biologically active molecules that could be used for nutraceutical purposes.
Agroecosystems represent more and more a huge long-term sink for plastic compounds which inevitably undergo fragmentation, generating micro- and nano-plastics, with potential adverse effects on soil chemistry and living organisms. The present work was focused on the short-term effects of two different concentrations of polystyrene nanoplastics (PSNPs) (0.1 or 1 g L-1 suspensions) on rice seedlings starting from seed germination, hypothesizing that possible acute effects on seedlings could depend on oxidative damage trigged by PSNPs internalization. As shown by TEM analysis, PSNPs were absorbed by roots and translocated to the shoots, affected root cell ultrastructure, the germination process, seedling growth and root mitotic activity, inducing cytogenetic aberration. Treatments were not correlated with increase in oxidative stress markers, but rather with a different pattern of their localization both in roots and in shoots, impairing H2O2 homeostasis and membrane damage, despite the adequate antioxidant response recorded. The harmful effects of PSNPs on cell biology and physiology of rice seedlings could be caused not only by a direct action by the PSNPs but also by changes in the production/diffusion of ROS at the tissue/cellular level.
Microplastics (MPs) and nanoplastics (NPs) are ubiquitous in natural habitats and the risks their presence poses to marine environments and organisms are of increasing concern. There is evidence that seagrass meadows are particularly prone to accumulate plastic debris, including polystyrene particles, but the impacts of this pollutant on seagrass performance are currently unknown. This is a relevant knowledge gap as seagrasses provide multiple ecosystem services and are declining globally due to anthropogenic impact and climate-change-related stressors. Here, we explored the potential effects of a 12 day-exposure of seagrasses to one concentration (68 μg/L) of polystyrene MPs and NPs on the growth, oxidative status, and photosynthetic efficiency of plants using the foundation species Cymodocea nodosa as a model. Among plant organs, adventitious roots were particularly affected by MPs and NPs showing complete degeneration. The number of leaves per shoot was lower in MPs- and NPs-treated plants compared to control plants, and leaf loss exceeded new leaf production in MPs-treated plants. MPs also reduced photochemical efficiency and increased pigment content compared to control plants. Shoots of NPs-treated plants showed a greater oxidative damage and phenol content than those of control plants and MPs-treated plants. Biochemical data about oxidative stress markers were consistent with histochemical results. The effects of MPs on C. nodosa could be related to their adhesion to plant surface while those of NPs to entering tissues. Our study provides the first experimental evidence of the potential harmful effects of MPs/NPs on seagrass development. It also suggests that the exposure of seagrasses to MPs/NPs in natural environments could have negative consequences on the functioning of seagrass ecosystems. This stresses the importance of implementing cleaning programs to remove all plastics already present in marine habitats as well as of undertaking specific actions to prevent the introduction of these pollutants within seagrass meadows.
Consequence of polystyrene particles size and concentration in plant tissues contamination.
Biosolids (Bs) for use in agriculture are an important way for introducing and transferring TiO2 nanoparticles (NPs) to plants and food chain. Roots of Pisum sativum L. plants grown in Bs-amended soils spiked with TiO2 800 mg/kg as rutile NPs, anatase NPs, mixture of both NPs and submicron particles (SMPs) were investigated by Transmission Electron Microscopy (TEM), synchrotron radiation based micro X-ray Fluorescence and micro X-ray Absorption Near-Edge Structure (µXRF/µXANES) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). TEM analysis showed damages in cells ultrastructure of all treated samples, although a more evident effect was observed with single anatase or rutile NPs treatments. Micro-XRF and TEM evidenced the presence of nano and SMPs mainly in the cortex cells near the rhizodermis. Micro-XRF/micro-XANES analysis revealed anatase, rutile, and ilmenite as the main TiO2 polymorphs in the original soil and Bs, and the preferential anatase uptake by the roots. For all treatments Ti concentration in the roots increased by 38–56%, however plants translocation factor (TF) increased mostly with NPs treatment (261–315%) and less with SMPs (about 85%), with respect to control. In addition, all samples showed a limited transfer of TiO2 to the shoots (very low TF value). These findings evidenced a potential toxicity of TiO2 NPs present in Bs and accumulating in soil, suggesting the necessity of appropriate regulations for the occurrence of NPs in Bs used in agriculture.
Phytoremediation represents a natural method to remove contaminants from soil. The goal of this study was to investigate the potential of phosphate-assisted phytoremediation by two energy crops, Cannabis sativa L. and Brassica juncea L., for the sustainable remediation of heavily arsenic-contaminated industrial soil. The two species were investigated for uptake, translocation, and physiological effects of arsenic and phosphate in a microcosm test. Although C. sativa and B. juncea were symptomless when grown in arsenic-contaminated soil, an important reduction of biomass (50 and 25%, respectively) was observed as a stress marker. Phytotoxicity and cytotoxicity effects promoted by contaminated soils were investigated in both the species and a model plant for ecotoxicity studies, Vicia faba L., which is the most developed model to test genotoxicity effects in terms of chromosomal aberration and micronuclei presence. The higher amount of arsenic was found in C. sativa and B. juncea roots (on average 1473 and 778 mg kg-1, respectively), but both species were able to uptake and translocate arsenic in leaves and stems, up to 47.0 and 189 mg kg-1, respectively. Phosphate treatment had no effect on arsenic uptake in none of the crop, but significantly improved the plant performance. Biomass production resulted similar to that of B. juncea control plants. Antioxidant enzymatic activities and photosynthetic performance responded differently in the two crops. The present investigation provides new insight for a proficient selection of the most suitable crop species for sustainable phytomanagement of a highly polluted As-contaminated site by coupled phytoremediation-bioenergy approach.
In the analysis by electrospray (+) of an extract of hemp sprouts put in a polypropylene vial, we found a large contamination of a plastic additive. It was characterized by multiple-stage MSn experiments (MS ÷ MS10 ) and identified as tris(2,4-di-tert-butylphenyl)phosphate, also known with the synonyms F32IRS6B46, oxidized Naugard 524, and others. The MS2 ÷ MS7 spectra are characterized by consecutive eliminations of six isobutene molecules from the tert-butyl moieties, some of them also occurring in the ion source. The first three are calculated to occur preferentially from the ortho positions, whereas eliminations from the para positions are estimated to be less favored at about 5-6 kcal/mol in each step. Once the first three isobutene molecules are eliminated, the remaining three are lost from the tert-butyl moieties in para positions (MS5 ÷ MS7 ), yielding protonated triphenylphosphate, whose structure has been confirmed by the MS2 spectrum of triphenylphosphate standard: the latter spectrum is almost superimposable with the MS8 spectrum of the analyte under investigation. MS8 and MS9 spectra show main losses of water and C6 H4 molecules. The MS10 spectrum of precursor ions at m/z 215 shows the gas-phase addition of water and methanol and ions at m/z 168, attributable to the loss of a phosphorus oxide radical. Density functional theory (DFT) calculations (Becke 3LYP [B3LYP] 6-311+G(2d,2p)) have been used to evaluate structure and stability of different ionic and neutral species involved in the decomposition pathways and to calculate thermochemical data of the decomposition reactions. This multistep mass analysis combined with theoretical calculations resulted to be particularly useful and effective, yielding chemical, thermochemical, and mechanistic data of significant utility in the structural characterization and identification of the unknown analyte as well as to define its gas-phase reactivity under a multistep low-energy collision-induced dissociation regime.