Search Results (2,413)

Meta-cresol (m-cresol) is highly corrosive and toxic, and is widely present in industrial wastewater. As a pollutant, it adversely affects various aspects of human production and daily life. To evaluate the feasibility of using sunflowers to remediate m-cresol-contaminated wastewater, this study used Helianthus annuus L. as the test subject to analyze its tolerance and the wastewater purification efficiency under different m-cresol concentrations. The results showed that the net photosynthetic rate (P_n), transpiration rate (T_r), stomatal conductance (G_s), and light energy utilization efficiency (LUE) of Helianthus annuus L. exhibited an overall decreasing trend, while the intercellular CO₂ concentration (Cᵢ) initially increased and subsequently decreased with increasing m-cresol concentration. When m-cresol concentration reached or exceeded 60 mg·L⁻¹, the net photosynthetic rate and intercellular CO₂ concentration in the leaves showed opposite trends with further increases in m-cresol stress. The inhibition of net photosynthesis in sunflowers by m-cresol was mainly attributed to non-stomatal factors. The maximum photochemical efficiency (F_v/F_m), actual photochemical efficiency (ΦPSII), photochemical quenching coefficient (q^P), PSII excitation energy partition coefficient (α), and the fraction of absorbed light energy used for photochemistry (P) all decreased with increasing m-cresol concentration. In contrast, non-photochemical quenching (NPQ), the quantum yield of regulated energy dissipation [Y(NPQ)], and the fraction of energy dissipated as heat through the antenna (D) first increased and then decreased. Under low-concentration m-cresol stress, sunflowers protected their photosynthetic system by dissipating excess light energy as heat as a stress response. However, high concentrations of m-cresol caused irreversible damage to Photosystem II (PSII) in sunflowers. Under m-cresol stress, chlorophyll a exhibited strong stability with minimal degradation. As the m-cresol concentration increased from 30 to 180 mg·L⁻¹, the removal rate decreased from 84.91% to 11.84%. In conclusion, sunflowers show good remediation potential for wastewater contaminated with low concentrations of m-cresol and can be used for treating m-cresol wastewater with concentrations ≤ 51.9 mg·L⁻¹. Full article

In the context of contemporary climate change, drought is widely recognized as a major stressor affecting plant growth. While numerous studies have demonstrated that Serendipita indica enhances stress resistance in host plants and is widely used in agriculture, research on its symbiotic interactions with woody plants for improving drought tolerance remains limited. This study investigated the effects of S. indica inoculation on the growth of Phoebe sheareri seedlings under varying drought conditions—well-watered (WW), moderate drought (MD), and severe drought (SD)—and explored the physiological mechanisms underlying improved drought resistance. The results showed that under WW conditions, S. indica inoculation promoted seedling growth and development. Under MD and SD conditions, although drought stress inhibited growth, inoculation significantly increased plant biomass, root parameters, chlorophyll content, and photosynthetic efficiency. Additionally, it alleviated drought-induced damage by reducing REC, MDA, H₂O₂, and O₂⁻ levels, while enhancing SOD, POD, and CAT activities, and increasing root ABA, GA, IAA, and CTK content. Under MD stress, adaptive changes in root architecture and hormone levels were observed, including increases in total root length, surface area, volume, average diameter, and elevated IAA and CTK levels—all of which were further enhanced by S. indica inoculation. In conclusion, symbiosis with S. indica improved drought tolerance in P. sheareri seedlings likely through enhanced photosynthesis, antioxidant enzyme activity, and hormone regulation. Full article

Chaenomeles japonica (Chaenomeles japonica Thunb. Lindl. ex Spach.) is gaining increasing attention due to its high nutritional value and potential for industrial use. The development of new breeding clones (potential new cultivars) with improved morphological and chemical properties is essential for enhancing its commercial cultivation. In this study, the impact of ozone in its gaseous form and cold storage on the morphological and chemical properties of newly selected Polish clones of Chaenomeles japonica was determined. Breeding clone ‘3b/1’ produced the largest fruits, with a significantly higher average weight of 99.8 g compared to other clones. Fruits of clones ‘3b/1’ and ‘7d/8’ had the greatest tolerance to mechanical damage, requiring the highest force and energy for puncture and showing the most extensive deformation. The highest ascorbic acid content was recorded in clone ‘4c/1’ (117.3 mg·100 g⁻¹), while clone ‘3b/1’ had the highest total phenolic content, reaching 373.92 mg GAE·100 g⁻¹. A 15 min ozone treatment led to an average increase of 5.3% in both ascorbic acid and total phenolic content. In contrast, cold storage for 60 days caused a reduction of approximately 29.66% of ascorbic acid. Clone ‘3b/1’ appears to be the potential new Polish cultivar and an introduction for cultivation due to its large fruit size, their high mechanical tolerance and relatively favorable chemical composition. Full article

Frequent and increasingly severe freezing events threaten citrus production in northern Florida, underscoring the need for strategies that enhance freezing resilience in citrus cultivars. Grafting scions onto tolerant rootstocks provides a physiologically integrative approach to improve stress tolerance. This study aims to elucidate how these interactions modulate physiological and metabolic responses under freezing stress, thereby identifying mechanisms that contribute to enhanced freeze resilience in citrus. Here, we grafted Citrus reticulata (cv. UF-950) onto eight rootstocks (Bitters, Blue-1, C-146, Sour Orange, UFR07TC, UFR09TC, UFR5, and US942) to evaluate scion–rootstock interactions under normal (20 °C) and freezing (−6 °C) conditions. Freezing stress caused a sharp increase in oxidative stress markers, lipid peroxidation, and membrane damage while reducing photosynthetic performance across most combinations. Antioxidant capacity, osmolyte accumulation, and carbon–nitrogen metabolic responses varied significantly among rootstocks, revealing strong genotype-dependent modulation of scion physiology. Among the tested combinations, UF-950 grafted onto UFR5 displayed the highest freezing tolerance, characterized by robust activation of antioxidant enzymes, elevated proline and glycine betaine accumulation, reduced oxidative damage, and sustained carbon–nitrogen metabolic fluxes under freezing stress. These results demonstrate that rootstock genotype governs the extent of scion defense activation and metabolic homeostasis under freezing conditions. Our findings identify UFR5 as a promising rootstock for enhancing freezing resilience in citrus and provide mechanistic insight into how scion–rootstock interaction orchestrates integrative stress tolerance pathways. Future work should focus on multi-omics dissection of rootstock-mediated signaling networks and long-term field validation to optimize rootstock selection for enhanced cold resilience under variable climatic conditions. Full article

Keratinous biomass, such as feathers, wool, and hair, poses environmental challenges due to its insoluble and recalcitrant nature. In this study, we identified, purified and comprehensively characterized a previously uncharacterized extracellular alkaline keratinase, KerFJ, secreted by Bacillus sp. FJ-3-16, with broad industrial application potential. KerFJ was produced at high yield (1800 U/mL) in an optimized cost-effective medium and purified to homogeneity using ion-exchange chromatography. The enzyme exhibited optimal activity at pH 9.5 and 55 °C, with remarkable alkaline and thermal stability, and high tolerance to surfactants, oxidants, and metal ions. Sequence analysis revealed that KerFJ is a member of the serine peptidase S8 family, with a molecular weight of ~27.5 kDa. It efficiently degraded native keratin substrates, achieving 70.3 ± 2.1% feather, 39.7 ± 1.8% wool, and 15.4 ± 1.2% hair degradation, and the resulting feather hydrolysates exhibited strong antioxidant activities. KerFJ also demonstrated excellent compatibility with commercial detergents and enabled effective stain removal from fabrics without damage. Moreover, both laboratory- and pilot-scale trials showed that KerFJ facilitated non-destructive dehairing of sheep, donkey, and pig skins while preserving collagen integrity. These results highlight KerFJ as a robust and multifunctional biocatalyst suitable for keratin waste valorization, eco-friendly leather processing, and detergent formulations. Full article

Reactive oxygen species (ROS) function as critical signaling molecules in cancer biology, promoting proliferation, angiogenesis, and metastasis at controlled levels while inducing lethal damage when exceeding the cell’s buffering capacity. To survive under this state of chronic oxidative stress, cancer cells become dependent on a hyperactive antioxidant shield, primarily orchestrated by the Nrf2, glutathione (GSH), and thioredoxin (Trx) systems. These defenses maintain redox homeostasis and sustain oncogenic signaling, notably through the oxidative inactivation of tumor-suppressor phosphatases, such as PTEN, which drives the PI3K/AKT/mTOR pathway. Targeting this addiction to a rewired redox state has emerged as a compelling therapeutic strategy. Pro-oxidant therapies aim to overwhelm cellular defenses, with agents like high-dose vitamin C and arsenic trioxide (ATO) showing significant tumor-selective toxicity. Inhibiting the master regulator Nrf2 with compounds such as Brusatol or ML385 disrupts the core antioxidant response. Disruption of the GSH system by inhibiting cysteine uptake with sulfasalazine or erastin potently induces ferroptosis, a non-apoptotic cell death driven by lipid peroxidation. Furthermore, the thioredoxin system is targeted by the repurposed drug auranofin, which irreversibly inhibits thioredoxin reductase (TrxR). Extensive preclinical data and ongoing clinical trials support the concept that this reliance on redox adaptation is a cancer-selective vulnerability. Moreover, novel therapeutic strategies, including the expanding field of redox-active metal complexes, such as manganese porphyrins, which strategically leverage the differential redox state of normal versus cancer cells through both pro-oxidant and indirect Nrf2-mediated antioxidative mechanisms (triggered by Keap1 oxidation), with several agents currently in advanced clinical trials, have also been discussed. Essentially, pharmacologically tipping the redox balance beyond the threshold of tolerance offers a rational and powerful approach to eliminate malignant cells, defining a novel frontier for targeted cancer therapy. Full article

Ceramic matrix composites (CMCs) are promising candidates for high-temperature structural applications. However, their fracture toughness remains low due to strong chemical bonding between fibers and the matrix. To improve toughness, engineered interfaces such as pyrolytic carbon (PyC) and hexagonal boron nitride (h-BN) are commonly introduced. These interfaces promote crack deflection and fiber bridging, leading to improved damage tolerance and pseudo-ductile behavior. To investigate the influence of interface thickness on mechanical performance and to identify optimal thickness ranges, we propose a microscopic phase-field model that accurately resolves interface thickness and material contrast. This model overcomes the limitations of conventional smeared interface approaches, particularly in systems with variable interface thickness and closely packed fibers. We apply the model to simulate the fracture behavior of unidirectional SiC fiber reinforced SiC matrix (SiC_f/SiC_m) composites with PyC and h-BN interfaces of varying thickness. The numerical results show strong agreement with experimental findings from the literature and reveal optimal interface thicknesses that maximize toughening effects. These results demonstrate the model’s predictive capabilities and its potential as a tool for interface design in brittle composite systems. Full article

This study aims to investigate the role of exogenous spermidine (Spd) in mitigating the adverse effects of cadmium (Cd) stress on the growth and development of cucumber (Cucumis sativus). The cucumber cultivar “Xintaimici” was used as the experimental material, and a hydroponic experiment was carried out. Based on a baseline Cd concentration of 10 mg·L⁻¹, Spd was supplemented at concentrations of 0.05, 0.1, 0.2, 0.4, and 0.5 mM, resulting in seven treatment groups: control group (CK), S0 group (Cd-only treatment, 10 mg·L⁻¹ Cd + 0 mM Spd), S1+ Cd group (10 mg·L⁻¹ Cd + 0.05 mM Spd), S2+ Cd group (10 mg·L⁻¹ Cd + 0.1 mM Spd), S3+ Cd group (10 mg·L⁻¹ Cd + 0.2 mM Spd), S4+ Cd group (10 mg·L⁻¹ Cd + 0.4 mM Spd), and S5+ Cd group (10 mg·L⁻¹ Cd + 0.5 mM Spd). This study analyzed the regulatory effects of Spd on the growth and development, antioxidant capacity and cadmium accumulation characteristics of cucumber seeds and seedlings. It was found that cadmium stress significantly inhibited their growth process and led to a decline in multiple physiological indicators. Under a Cd concentration of 10 mg·L⁻¹, the application of 0.2 mM Spd significantly improved these parameters. During the seedling stage, the application of 0.2 mM Spd under Cd stress significantly enhanced the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), as well as the content of soluble proteins, while significantly reducing malondialdehyde (MDA) levels. Cd content analysis revealed that 0.2 mM Spd promoted Cd accumulation in roots while suppressing its translocation to young leaves, thereby reducing Cd accumulation in aboveground tissues. Gene expression analysis demonstrated that this treatment significantly upregulated the expression levels of the phytochelatin synthase gene (CsPCS1) and the gene associated with reduced glutathione synthesis (CsGSHS). In conclusion, the exogenous application of 0.2 mM Spd effectively alleviates oxidative damage and osmotic stress induced by Cd stress in cucumber, promotes plant growth, and significantly enhances Cd tolerance. Full article

This study characterised the diversity of filamentous fungi and yeasts during Malbec grape fermentation in the Southern Oasis of Mendoza (Argentina) winegrowing region, under different sanitary conditions and SO₂ treatments, using morphological and ITS-RFLP-based molecular methods. Alternaria, Cladosporium and Penicillium were present in both sound and damaged grapes, while Aspergillus and Botrytis were primarily found in damaged grapes. The predominant yeast species in both sound and damaged grape must, at lower and higher maturity levels, were Aureobasidium pullulans and Hanseniaspora spp. At higher grape ripening levels species diversity increased, with Hanseniaspora vineae, Metschnikowia pulcherrima and Candida membranifaciens dominating, and others such as Pichia kudriavzevii and Issatchenkia terricola appearing. A. pullulans and M. pulcherrima were highly tolerant to SO₂. Notably, the species Meyerozyma guilliermondii, Zygoascus hellenicus and Hanseniaspora uvarum were exclusively present in damaged grape must, while Zygosaccharomyces bailii was also found in sound grape must. Hanseniaspora spp. and P. kudriavzevii predominated at mid-fermentation and persisted at the end of the process, highlighting their resistance to wine conditions and their potential to influence post-fermentative dynamics. These findings emphasise the significant influence of grape sanitary status on mycobiota composition, with important implications for fermentation behaviour and final wine quality. Full article

Abiotic stressors such as drought, salinity, waterlogging, and high and low temperatures significantly reduce the growth and productivity of rice (Oryza sativa) and soybean (Glycine max), which are vital for global food and nutritional security. These stressors disrupt physiological, biochemical, and molecular processes, resulting in decreased yield and quality. Biostimulants represent promising sustainable solutions to alleviate stress-induced damage and improve crop performance under stressful conditions. This review provides a comprehensive analysis of the role of biostimulants in enhancing rice and soybean resilience under abiotic stress. Both microbial and non-microbial biostimulants including phytohormones such as salicylic acid; melatonin; humic and fulvic substances; seaweed extracts; nanoparticles; and beneficial microbes have been discussed. Biostimulants enhance antioxidant defenses, improve photosynthesis and nutrient uptake, regulate hormones, and activate stress-responsive genes, thereby supporting growth and yield. Moreover, biostimulants regulate molecular pathways such as ABA- and ROS-mediated signaling and activate key transcription factors (e.g., WRKY, DREB, NAC), linking molecular responses with physiological and phenotypic resilience. The effectiveness of biostimulants depends on crop species, growth stage, stress severity and application method. This review summarizes recent findings on the role of biostimulants in enhancing the mechanisms underlying growth, yield, and stress tolerance of rice and soybean under abiotic stress. Additionally, the incorporation of biostimulants into sustainable farming practices to increase productivity in the context of climate-related challenges has been discussed. Furthermore, the necessity for additional research to elucidate the underlying mechanisms, refine application methods, and verify their effectiveness in field conditions has been highlighted. Full article

Pollution from heavy metals represents one of the most important threats to crops. Among these, Nickel (Ni) represents a dangerous element, strictly related to anthropic activity and easily accumulated in plants. In this study, effects of high levels (1 mM) of Ni²⁺ were investigated in barley (Hordeum vulgare L. cv. Nure) grown hydroponically, inducing a severe reduction in plant growth, as well as genotoxic damage. Moreover, stress affects photosynthesis, inducing a decrease in Fv/Fm and ΦPSII and an increase in D1 protein and RuBisCO (RbcL) abundance to compensate for the loss of photosynthetic efficiency. Changes were observed in carbon metabolism, with increases in phosphofructokinase, glyceraldehyde-3P dehydrogenase-NAD⁺, and pyruvate kinase expression confirmed by increased proteins and activities. Notably, there was an evident rise in PEP carboxylase activity, presence, and expression. This increase boosts the TCA cycle (increased fumarase) and supports photorespiration. Evident rises were observed also for glucose-6P dehydrogenase activity and presence. Ni²⁺ stress induced an evident increase in enzymes involved in nitrogen metabolism: particularly, the chloroplastic GS2/Fd-GOGAT cycle and N assimilation through the cytosolic glutamate dehydrogenase reaction were enhanced. These results design a specific stress-responsive metabolism by diverting the synthesis of N-compounds through alternative C/N assimilation pathways to counteract the effects of Ni²⁺ toxicity. This study depicts a diversion of the main C/N metabolism network towards an increase in leaf N assimilation, using carbon skeletons from dark CO₂ fixation under high Ni²⁺ stress. These results may provide possible targets for the improvement of heavy metal tolerance in cereals. Full article

Copper is a vital micronutrient for animals and plants acting as a crucial cofactor in the synthesis of numerous metabolic enzymes and contributing to mitochondrial respiration, metabolism, oxido-reductive reactions, signal transmission, and oxidative and nitrosative damage. In the cells, copper may exist in the Cu⁺ and Cu⁺⁺ oxidation states and the interconversion between these two states may occur via various redox reactions regulating cellular respiration, energy metabolism, and cell growth. The human body maintains a low level of copper, and copper deficiency or copper excess may adversely affect cellular functions; therefore, regulation of copper levels within a narrow range is important for maintaining metabolic homeostasis. Recent studies identified a new copper-dependent form of cell death called cuproptosis. Cuproptosis occurs due to copper binding to lipoylated enzymes (for instance, pyruvate dehydrogenase and α-ketoglutarate dehydrogenase) in the tricarboxylic acid Krebs cycle. In recent years, extensive studies on copper homeostasis and copper-induced cell death in degenerative disorders, like Menkes, Wilson, Alzheimer, Parkinson’s, Huntington’s diseases, and Amyotrophic Lateral Sclerosis, have discussed the therapeutic potential of targeting cuproptosis. Copper contamination in the environment, which has increased in recent years due to the expansion of agricultural and industrial activities, is associated with a wide range of human health risks. Soil used for the cultivation of grapes has a long history of copper-based fungicide application (the Bordeaux mixture is rich in copper) resulting in copper accumulation at levels capable of causing toxicity in plants that co-inhabit the vineyards. Phytoremediation, which uses plants and biological solutions to remove toxic heavy metals and pesticides and other contaminants from soil and water, is an environmentally friendly and cost-effective technology used for the removal of copper. It requires plants to be tolerant of high levels of copper and capable of accumulating metal copper in plants’ aerial organs and roots. This review aims at highlighting the importance of copper as an essential metal, as well as its involvement in cuproptosis and neurodegenerative diseases. Full article

Cadmium (Cd) is a toxic metal that affects living organisms even at low concentrations, causing physiological alterations and biomass reduction in plants. Arbuscular mycorrhizal fungi (AMF) represent a biological strategy that increases tolerance to heavy metals, although their specific mechanisms in sugarcane remain poorly understood. To address this knowledge gap, an open-field experiment was conducted to evaluate the effects of AMF on Cd accumulation, oxidative stress, photosynthetic pigments, enzymatic antioxidant system, and non-enzymatic antioxidant compounds in sugarcane variety CC 01-1940, using a randomized block design. Results showed that AMF established symbiosis with plants, retaining Cd in the roots and reducing its translocation to leaves. Additionally, they decreased Cd-induced oxidative stress by reducing lipid peroxidation (MDA) and proline content. Although an initial decrease in photosynthetic capacity was observed, AMF helped maintain stable levels of photosynthetic pigments, preserving photosynthetic efficiency. They also activated antioxidant enzymes and increased antioxidant compounds such as reduced glutathione (GSH), non-protein thiols (NP-SH), ascorbic acid (AA), and phytochelatins (PC). These findings demonstrate that symbiosis with AMF protects sugarcane plants from cellular oxidative damage and reduces Cd concentrations in leaves. Therefore, the use of AMF represents an effective strategy to improve the antioxidant defense and resistance of sugarcane plants to cadmium stress. Full article

Soil acidification from excessive nitrogen and potassium fertilization in protected cucumber systems impairs calcium uptake, triggering physiological calcium deficiency and reducing yield. We investigated whether the plant growth-promoting rhizobacterium Bacillus amyloliquefaciens QST713 could mitigate low-calcium stress in cucumber (‘Jinyou No. 4’). Under controlled nutrient solution irrigation (4, 0.4, and 0 mmol/L Ca²⁺, with or without B. amyloliquefaciens QST713), low-calcium conditions suppressed growth, reduced ion uptake capacity, photosynthetic pigment content, gas exchange (Pn, Gs, Tr), PSII efficiency (ΦPSII, ETR), and decreased carbohydrate (starch, sucrose) accumulation, while disrupting nitrogen balance (decreases in NO₃⁻-N, soluble protein, and amino acids; increase in NH₄⁺-N) and inhibiting key N-assimilation enzymes (NR, GS, GOGAT, GDH). Inoculation with B. amyloliquefaciens QST713 reversed these effects: it enhanced ion acquisition, chlorophyll content, and photosynthetic performance; restored carbohydrate reserves; promoted NO₃⁻ uptake and NH₄⁺ assimilation; and upregulated N-metabolizing enzyme activities. Principal component analysis confirmed strong coupling among growth, photosynthesis, and C-N metabolism. In summary, low-calcium stress markedly inhibited cucumber growth, suppressed photosynthetic activity, and reduced the levels of carbon and nitrogen metabolism. Application of B. amyloliquefaciens QST713 effectively alleviated the physiological damage caused by low-calcium stress, enhancing photosynthetic performance and thereby accelerating the synthesis and turnover of carbon- and nitrogen-containing metabolites. These effects collectively improved cucumber tolerance to low-calcium conditions and promoted plant growth and development. This study provides a preliminary theoretical basis for further exploration of the stress-resistance capacity of B. amyloliquefaciens. Full article

The yellow passion fruit is a key crop in irrigated areas of Northeast Brazil, but production is challenged by limited water availability and high salinity in groundwater used for irrigation. This study evaluated the effects of grafting Passiflora edulis f. flavicarpa Degener (E) onto P. foetida L. (F) rootstock to reduce the impact of saline stress. Conducted in a greenhouse using a 3 × 2 factorial design with four replications, the experiment tested three grafting combinations (F + F, E + E and E + F) under two salinity levels (0.5 and 6.0 dS m⁻¹). Key parameters measured included SPAD index, soluble protein content, hydrogen peroxide (H₂O₂) levels, catalase enzyme activity, plant height, and leaf number. Salinity significantly reduced plant height, especially at 6.0 dS m⁻¹. The E + E combination had the highest protein content in roots (23.8%). However, grafting P. edulis onto P. foetida (E + F) enhanced catalase activity and reduced H₂O₂ accumulation, indicating improved tolerance to salt stress. The findings suggest that using P. foetida as a rootstock may help mitigate oxidative damage and promote better physiological performance of yellow passion fruit under saline conditions, offering a strategy to sustain cultivation in stress-prone environments. Full article