Metabolic Pathway of Natural Antioxidants, Antioxidant Enzymes and ROS Providence

An insight into heat stress response and adaptive mechanism in cotton

The growing worldwide population is driving up demand for cotton fibers, but production is hampered by unpredictable temperature rises caused by shifting climatic conditions. Numerous research based on breeding and genomics have been conducted to increase the production of cotton in environments with high and low-temperature stress. High temperature (HT) is a major environmental stressor with global consequences, influencing several aspects of cotton plant growth and metabolism. Heat stress-induced physiological and biochemical changes are research topics, and molecular techniques are used to improve cotton plants' heat tolerance. To preserve internal balance, heat stress activates various stress-responsive processes, including repairing damaged proteins and membranes, through various molecular networks. Recent research has investigated the diverse reactions of cotton cultivars to temperature stress, indicating that cotton plant adaptation mechanisms include the accumulation of sugars, proline, phenolics, flavonoids, and heat shock proteins. To overcome the obstacles caused by heat stress, it is crucial to develop and choose heat-tolerant cotton cultivars. Food security and sustainable agriculture depend on the application of genetic, agronomic, and, biotechnological methods to lessen the impacts of heat stress on cotton crops. Cotton producers and the textile industry both benefit from increased heat tolerance. Future studies should examine the developmental responses of cotton at different growth stages, emphasize the significance of breeding heat-tolerant cultivars, and assess the biochemical, physiological, and molecular pathways involved in seed germination under high temperatures. In a nutshell, a concentrated effort is required to raise cotton's heat tolerance due to the rising global temperatures and the rise in the frequency of extreme weather occurrences. Furthermore, emerging advances in sequencing technologies have made major progress toward successfully se sequencing the complex cotton genome.

Mytilus galloprovincialis: A valuable bioindicator species for understanding the effects of diclofenac under warming conditions

Drugs are chemical compounds used to treat and improve organic dysfunctions caused by diseases. These include analgesics, antibiotics, antidepressants, and antineoplastics. They can enter aquatic environments through wastewater streams, where their physico-chemical properties allow metabolites to distribute and accumulate. Current climate change and associated extreme weather events may significantly impact these substances' toxicity and aquatic organisms' sensitivity. Among the chemicals present in aquatic environments is the non-steroidal anti-inflammatory drug diclofenac (DIC), which the EU monitors due to its concentration levels. This study investigated the influence of temperature (control at 17 °C vs. 21 °C) on the effects of DIC (0 μg/L vs. 1 μg/L) in the mussel species Mytilus galloprovincialis. Significant results were observed between 17 and 21 °C. Organisms exposed to the higher temperature showed a decrease in several parameters, including metabolic capacity and detoxification, particularly with prolonged exposure. However, in some parameters, after 21 days, the M. galloprovincialis showed no differences from the control, indicating adaptation to the stress. The results of this study confirm that DIC concentrations in the environment, particularly when combined with increased temperatures, can produce oxidative stress and adversely affect M. galloprovincialis biochemical and physiological performance. This study also validates this species as a bioindicator for assessing environmental contamination with DIC. Beyond its direct impact on aquatic organisms, the presence of pharmaceuticals like DIC in the environment highlights the interconnectedness of human, animal, and ecosystem health, underscoring the One Health approach to understanding and mitigating environmental pollution.

Antioxidants from Rubus idaeus leaves: LC-MS/MS chemical profiling, in vitro antiglycation, α-glucosidase and α-amylase inhibitory activities

The present study evaluated a range of biological activities of Rubus idaeus leaves, often considered as by-products, in relation to hyperglycemia. The antiglycation potential of this plant has not been previously reported. In this research, the methanolic leaf extract of R. idaeus was assessed for its antioxidant, enzyme inhibitory and antiglycation activities. The bioactive compounds present in the extract were screened using LC-MS/MS. Enzyme inhibitory activities were tested on α-glucosidase and α-amylase, and the antiglycation effect was investigated using BSA-fructose model. The methanolic extract showed a high polyphenolic contents (176.26 ± 2.26 mg GAE/g) and important IC50 values for DPPH (34.79 ± 2.40 µg/mL) and ABTS radical scavenging activities (49.75 ± 2.47 µg/mL). In addition, the plant leaf extract significantly inhibited hyperglycemia-related enzymes in a dose-dependent manner and demonstrated a reduction in fluorescent AGEs, fructosamine, and dicarbonyl compounds. Therefore, R. idaeus cv Maravilla could be an effective source of therapeutics for improving the healthcare outcomes of diabetic patients.

A Bioinspired Photosensitizer Performs Tumor Thermoresistance Reversion to Optimize the Atraumatic Mild-Hyperthermia Photothermal Therapy for Breast Cancer

Mild-hyperthermia photothermal therapy (mPTT) has therapeutic potential with minimized damage to normal tissues. However, the poorly vascularized tumor area severely hampers the penetration of photothermal agents (PTAs), resulting in their heterogeneous distribution and the subsequent heterogeneous local temperature during mPTT. The presence of regions below the therapeutic 42 °C threshold can lead to incomplete tumor ablation and potential recurrence. Additionally, tumor anti-apoptosis and cytoprotection pathways, particularly activated thermoresistance, can nullify mild hyperthermia-induced tumor damage. Therefore, a bioinspired photosensitizer decorated with leucine to form biomimetic nanoclusters (CP-PLeu nanoparticles (NPs)) aimed at achieving rapid and homogeneous accumulation in tumors, is introduced. Moreover, CP-PLeu exhibits photodynamic effects that reverse tumor thermoresistance and physiological repair mechanisms, thereby inhibiting tumor resistance to hyperthermia. With the addition of NIR-II laser irradiation, CP-PLeu optimizes the therapeutic efficacy of mPTT and contributes to a minimally invasive therapeutic process for breast cancer. This therapeutic strategy, utilizing a biomimetic photosensitizer for homogeneous distribution of therapeutic temperature and photoactivated reversal of tumor thermoresistance, successfully achieves efficient breast tumor inhibition through an atraumatic mPTT process.

Prediction of Antioxidant Capacity of Thiolate-Disulfide Systems Using Species-Specific Basicity Values

The principal reactions that maintain redox homeostasis in living systems are the deprotonation of thiols, followed by the oxidative conversion of the produced thiolates into disulfides, which thus reduce the harmful oxidizing agents. The various biological thiols have different molecule-specific propensities to carry on the co-dependent deprotonation and redox processes. This study utilizes the known correlation between thiolate basicities and oxidizabilities, to quantify antioxidant or reducing capacities and pH-dependences of thiol-disulfide antioxidant systems, as a tool to find adequate molecules against oxidative stress.

Urban Air Pollution and Plant Tolerance: Omics Responses to Ozone, Nitrogen Oxides, and Particulate Matter

Urban air pollution is a crucial global challenge, mainly originating from urbanization and industrial activities, which are continuously increasing. Vegetation serves as a natural air filter for air pollution, but adverse effects on plant health, photosynthesis, and metabolism can occur. Recent omics technologies have revolutionized the study of molecular plant responses to air pollution, overcoming previous limitations. This review synthesizes the latest advancements in molecular plant responses to major air pollutants, emphasizing ozone (O3), nitrogen oxides (NOX), and particulate matter (PM) research. These pollutants induce stress responses common to other abiotic and biotic stresses, including the activation of reactive oxygen species (ROSs)-scavenging enzymes and hormone signaling pathways. New evidence has shown the central role of antioxidant phenolic compound biosynthesis, via the phenylpropanoid pathway, in air pollution stress responses. Transcription factors like WRKY, AP2/ERF, and MYB, which connect hormone signaling to antioxidant biosynthesis, were also affected. To date, research has predominantly focused on laboratory studies analyzing individual pollutants. This review highlights the need for comprehensive field studies and the identification of molecular tolerance traits, which are crucial for the identification of tolerant plant species, aimed at the development of sustainable nature-based solutions (NBSs) to mitigate urban air pollution.

Inside the genome: understanding genetic influences on oxidative stress

Genetics is a key factor that governs the susceptibility to oxidative stress. In the body, oxidative burden is regulated by the balance between the prooxidant genes that orchestrate processes that produce oxidant species, while the antioxidant genes aid those involved in scavenging these species. Together, the two components aid in maintaining the oxidative balance in the body. Genetic variations can influence the expression and activity of the encoded proteins which can then affect their efficiency in regulating redox processes, thereby increasing the risk of oxidative stress. This review studies single nucleotide polymorphisms (SNPs) that bear relevance to oxidative stress by exploring the variations in the prooxidant genes, such as XDH, CYBA, CYP1A1, PTGS2, NOS, and MAO and antioxidant genes including SOD, CAT, GPX, GSS, GLUL, GSR, GSTM1, GSTM5, GSTP1, TXN and HMOX1. Early identification of individuals at the increased risk of oxidative stress is possible from the assessment of sequence of these genes. Integrating genetic insights into oxidative stress management measures can pave the way for personalized medicine that tailors' healthcare approaches to individual genetic profiles. Effective genetic assessment along with routine quantification of biological markers can improve and monitor treatment strategies, enhancing mitigation approaches that maintain cellular health and promote longevity.

Current state of knowledge of triclosan (TCS)-dependent reactive oxygen species (ROS) production

Triclosan (TCS) is widely used in a number of industrial and personal care products. This molecule can induce reactive oxygen species (ROS) production in various cell types, which results in diverse types of cell responses. Therefore, the aim of the present study was to summarize the current state of knowledge of TCS-dependent ROS production and the influence of TCS on antioxidant enzymes and pathways. To date, the TCS mechanism of action has been widely investigated in non-mammalian organisms that may be exposed to contaminated water and soil, but there are also in vivo and in vitro studies on plants, algae, mammalians, and humans. This literature review has revealed that mammalian organisms are more resistant to TCS than non-mammalian organisms and, to obtain a toxic effect, the effective TCS dose must be significantly higher. The TCS-dependent increase in the ROS level causes damage to DNA, protein, and lipids, which together with general oxidative stress leads to cell apoptosis or necrosis and, in the case of cancer cells, faster oncogenesis and even initiation of oncogenic transformation in normal human cells. The review presents the direct and indirect TCS action through different receptor pathways.

Secondary metabolites in topical infectious diseases and nanomedicine applications

Topical infection affects nearly one-third of the world's population; it may result from poor sanitation, hygienic conditions and crowded living and working conditions that accelerate the spread of topical infectious diseases. The problems associated with the anti-infective agents are drug resistance and long-term therapy. Secondary metabolites are obtained from plants, microorganisms and animals, but they are metabolized inside the human body. The integration of nanotechnology into secondary metabolites is gaining attention due to their interaction at the subatomic and skin-tissue levels. Hydrogel, liposomes, lipidic nanoparticles, polymeric nanoparticles and metallic nanoparticles are the most suitable carriers for secondary metabolite delivery. Therefore, the present review article extensively discusses the topical applications of nanomedicines for the effective delivery of secondary metabolites.

Embryo growth alteration and oxidative stress responses in germinating Cucurbita pepo seeds exposed to cadmium and copper toxicity

This study investigated the influence of cadmium (Cd) and copper (Cu) heavy metals on germination, metabolism, and growth of zucchini seedlings (Cucurbita pepo L.). Zucchini seeds were subjected to two concentrations (100 and 200 μM) of CdCl2 and CuCl2. Germination parameters, biochemical and phytochemical attributes of embryonic axes were assessed. Results revealed that germination rate remained unaffected by heavy metals (Cd, Cu). However, seed vigor index (SVI) notably decreased under Cd and Cu exposure. Embryonic axis length and dry weight exhibited significant reductions, with variations depending on the type of metal used. Malondialdehyde and H2O2 content, as well as catalase activity, did not show a significant increase at the tested Cd and Cu concentrations. Superoxide dismutase activity decreased in embryonic axis tissues. Glutathione S-transferase activity significantly rose with 200 μM CdCl2, while glutathione content declined with increasing Cd and Cu concentrations. Total phenol content and antioxidant activity increased at 200 μM CuCl2. In conclusion, Cd and Cu heavy metals impede zucchini seed germination efficiency and trigger metabolic shifts in embryonic tissue cells. Response to metal stress is metal-specific and concentration-dependent. These findings contribute to understanding the intricate interactions between heavy metals and plant physiology, aiding strategies for mitigating their detrimental effects on plants.

Integrated Metabolomics and Transcriptomics Analyses Highlight the Flavonoid Compounds Response to Alkaline Salt Stress in Glycyrrhiza uralensis Leaves

Glycyrrhiza uralensis is a saline-alkali-tolerant plant whose aerial parts are rich in flavonoids; however, the role of these flavonoids in saline-alkali tolerance remains unclear. Herein, we performed physiological, metabolomics, and transcriptomics analyses in G. uralensis leaves under alkaline salt stress for different durations. Alkaline salt stress stimulated excessive accumulation of reactive oxygen species and consequently destroyed the cell membrane, causing cell death, and G. uralensis initiated osmotic regulation and the antioxidant system to respond to stress. In total, 803 metabolites, including 244 flavonoids, were detected via metabolomics analysis. Differentially altered metabolites and differentially expressed genes were coenriched in flavonoid-related pathways. Genes such as novel.4890, Glyur001511s00039602, and Glyur000775s00025737 were highly expressed, and flavonoid metabolites such as 2'-hydroxygenistein, apigenin, and 3-O-methylquercetin were upregulated. Thus, flavonoids as nonenzymatic antioxidants play an important role in stress tolerance. These findings provide novel insights into the response of G. uralensis to alkaline salt stress.

Protective Effects of Xanthine Derivatives Against Arsenic Trioxide-Induced Oxidative Stress in Mouse Hepatic and Renal Tissues

In this study, the protective efficacy of pentoxifylline (PTX) as a xanthine derivative against arsenic trioxide (ATO)-induced kidney and liver damage in mice was investigated. Thirty-six mice were divided into six groups, receiving intraperitoneal injections of saline, ATO, PTX, or a combination for four weeks. Blood samples were analyzed for serum biochemistry, while hepatic tissue underwent examination for histopathological changes and assessment of oxidative stress markers and antioxidant gene expression through Real-Time PCR. ATO exposure significantly increased serum markers (creatinine, ALT, BUN, ALP, AST) and induced histopathological changes in the liver. Moreover, it elevated renal and hepatic nitric oxide (NO) and lipid peroxidation (LPO) levels, and reduced antioxidant enzyme expression (CAT, GSR, GPx, MPO, SOD), total thiol groups (TTGs), and total antioxidant capacity (TAC). Conversely, PTX treatment effectively lowered serum hepatic and renal markers, improved antioxidant markers, and induced histopathological alterations. Notably, PTX did not significantly affect renal and hepatic NO levels. These findings suggest that PTX offers therapeutic potential in mitigating liver and acute kidney injuries induced by various insults, including exposure to ATO.

ROS Scavenging Effect of Selected Isoflavones in Provoked Oxidative Stress Conditions in Human Skin Fibroblasts and Keratinocytes

Isoflavones, belonging to polyphenolic compounds, show structural similarity to natural estrogens, and in this context, they have been extensively studied. Some of them are also applied as cosmetic additives; however, little is known regarding their effects on skin cells. In this investigation, common isoflavones, including genistein, daidzein, glycitein, formononetin, and biochanin A, as well as coumestrol, were evaluated for antioxidant activity and their impact on human skin fibroblasts and keratinocytes. Antioxidant effects were assessed using DPPH, ABTS, and FRAP tests, and the ability to scavenge reactive oxygen species (ROS) was tested in cells with H2O2-provoked oxidative stress. The impact on the activity of antioxidant enzymes (SOD, CAT, GSH) and lipid peroxidation (MDA) was also explored. As shown by Alamar Blue and neutral red uptake assays, the compounds were not toxic within the tested concentration range, and formononetin and coumestrol even demonstrated a stimulatory effect on cells. Coumestrol and biochanin A demonstrated significant antioxidative potential, leading to a significant decrease in ROS in the cells stimulated by H2O2. Furthermore, they influenced enzyme activity, preventing depletion during induced oxidative stress, and also reduced MDA levels, demonstrating protection against lipid peroxidation. In turn, genistein, daidzein, and glycitein exhibited low antioxidant capacity.

Molecular Mechanism of Natural Food Antioxidants to Regulate ROS in Treating Cancer: A Review

Cancer is the second-highest mortality rate disease worldwide, and it has been estimated that cancer will increase by up to 20 million cases yearly by 2030. There are various options of treatment for cancer, including surgery, radiotherapy, and chemotherapy. All of these options have damaging adverse effects that can reduce the patient's quality of life. Cancer itself arises from a series of mutations in normal cells that generate the ability to divide uncontrollably. This cell mutation can happen as a result of DNA damage induced by the high concentration of ROS in normal cells. High levels of reactive oxygen species (ROS) can cause oxidative stress, which can initiate cancer cell proliferation. On the other hand, the cytotoxic effect from elevated ROS levels can be utilized as anticancer therapy. Some bioactive compounds from natural foods such as fruit, vegetables, herbs, honey, and many more have been identified as a promising source of natural antioxidants that can prevent oxidative stress by regulating the level of ROS in the body. In this review, we have highlighted and discussed the benefits of various natural antioxidant compounds from natural foods that can regulate reactive oxygen species through various pathways.

The fungal endophyte Metarhizium anisopliae (MetA1) coordinates salt tolerance mechanisms of rice to enhance growth and yield

The implementation of salt stress mitigation strategies aided by microorganisms has the potential to improve crop growth and yield. The endophytic fungus Metarhizium anisopliae shows the ability to enhance plant growth and mitigate diverse forms of abiotic stress. We examined the functions of M. anisopliae isolate MetA1 (MA) in promoting salinity resistance by investigating several morphological, physiological, biochemical, and yield features in rice plants. In vitro evaluation demonstrated that rice seeds primed with MA enhanced the growth features of rice plants exposed to 4, 8, and 12 dS/m of salinity for 15 days in an agar medium. A pot experiment was carried out to evaluate the growth and development of MA-primed rice seeds after exposing them to similar levels of salinity. Results indicated MA priming in rice improved shoot and root biomass, photosynthetic pigment contents, leaf succulence, and leaf relative water content. It also significantly decreased Na+/K+ ratios in both shoots and roots and the levels of electrolyte leakage, malondialdehyde, and hydrogen peroxide, while significantly increasing proline content in the leaves. The antioxidant enzymes catalase, glutathione S-transferase, ascorbate peroxidase, and peroxidase, as well as the non-enzymatic antioxidants phenol and flavonoids, were significantly enhanced in MA-colonized plants when compared with MA-unprimed plants under salt stress. The MA-mediated restriction of salt accumulation and improvement in physiological and biochemical mechanisms ultimately contributed to the yield improvement in salt-exposed rice plants. Our findings suggest the potential use of the MA seed priming strategy to improve salt tolerance in rice and perhaps in other crop plants.

Antioxidant properties of date seeds extract (Phoenix dactylifera L.) in alloxan induced damage in rats

The study was conducted to examine the antioxidant activity and evaluate the protective effects of the date seeds powder kentichi against alloxan-induced damage in the liver, kidney, and pancreas in diabetic's rats. Group 1: control group, that did not receive any treatment, Group 2: alloxan was injected intraperitoneally (120 mg/kg body weight) for two days (Diab), Group 3: treated only by date seeds powder added in the diet (300 g/kg) for 6 weeks (DSPK), Group 4: alloxan-diabetic rats treated with date seeds powder (300 g/kg) (DSPK + Diab). Estimations of biochemical parameters in blood were determined. TBARS, SOD, CAT, and GPx activities were determined. A histopathological study was done by immersing pieces of both organs in a fixative solution followed by paraffin hematoxylin-eosin staining. In addition, the antioxidant activities of DSPK were evaluated by DPPH radical scavenging activity, reducing power, and ABTS free radical scavenging. The results revealed that date seeds significantly decreased serum levels of glucose, cholesterol, triglycerides, urea, creatinine, T-protein, ALP, D-bili and T-bili levels. In addition, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities that had been reduced in liver, kidney, and pancreas of the treated group were restored by DSPK treatments and, therefore, the lipid peroxidation level was reduced in the liver, kidney and pancreas tissue compared to the control group. Additionally, the histological structure in these organs was restored after treatment with date seeds powder.

Membrane-Bound Transcription Factor ZmNAC074 Positively Regulates Abiotic Stress Tolerance in Transgenic Arabidopsis

Maize (Zea mays L.) is one of the most widely cultivated crops for humans, making a vital contribution to human nutrition and health. However, in recent years, due to the influence of external adverse environments, the yield and quality of maize have been seriously affected. NAC (NAM, ATAF1/2 and CUC2) transcription factors (TFs) are important plant-unique TFs, which are crucial for regulating the abiotic stress response of plants. Therefore, it is of great biological significance to explore the underlying regulatory function of plant NAC TFs under various abiotic stresses. In this study, wild-type and ZmNAC074-overexpressed transgenic Arabidopsis were used as experimental materials to dissect the stress-resistant function of ZmNAC074 in transgenic Arabidopsis at phenotypic, physiological and molecular levels. The analyses of seed germination rate, survival rate, phenotype, the content of chlorophyll, carotenoids, malondialdehyde (MDA), proline and other physiological indexes induced by distinct abiotic stress conditions showed that overexpression of ZmNAC074 could confer the enhanced resistance of salt, drought, and endoplasmic reticulum (ER) stress in transgenic Arabidopsis, indicating that ZmNAC074 plays an important regulatory role in plant response to abiotic stress, which provides an important theoretical foundation for further uncovering the molecular regulation mechanism of ZmNAC074 under abiotic stresses.

Effect of fed dietary yeast (Rhodotorula paludigena CM33) on shrimp growth, gene expression, intestinal microbial, disease resistance, and meat composition of Litopenaeus vannamei

Yeast is a health-promoting and bio-therapeutic probiotic that is commonly used in aquaculture. Rhodotorula paludigena CM33 can accumulate amounts of intracellular carotenoids and lipid, which are regarded as nutritionally beneficial compounds in various aspects. The aim of this study was to evaluate the impact of different levels of R. paludigena CM33 (RD) incorporated in a dietary composition at 0% (control), 1% (1% RD), 2% (2% RD), and 5% (5% RD) on the growth of shrimp (Litopenaeus vannamei), their immune-related gene expression, intestinal health, resistance to Vibrio parahaemolyticus (VPAHPND) infection, and meat composition. The results showed significant improvements in the specific growth rate, weight gain, and survival of shrimp fed with 1% RD, 2% RD, and 5% RD, which were higher than the control group after 4 weeks of administration. The administration of 5% RD group resulted in a decrease in cumulative mortality upon VPAHPND challenge when compared to the control group. Furthermore, the expression levels of immune-responsive genes, including proPO system (prophenoloxidase-2: PO2), antioxidant enzyme (superoxide dismutase: SOD, glutathione peroxidase: GPX, and catalase: CAT), JAK/STAT pathway (signal transducer and activator of transcription: STAT, gamma interferon inducible lysosomal thiol reductase: GILT), IMD pathway (inhibitor of nuclear factor kappa-B kinase subunit beta and epsilon: IKKb and IKKe), and Toll pathway (Lysozyme) genes, were up-regulated in the 5% RD group. In the context of microbiota, microbiome analysis revealed that the main phyla in shrimp intestines were Proteobacteria, Firmicutes, Bacteroidota, Campilobacterota, Actinobacteriota, and Verrucomicrobiota. At the genus level, Vibrio was found to be reduced in the 5% RD group, whereas the abundance of potentially beneficial bacteria Bifidobacterium was increased. The 5% RD group showed a significant increase in the levels of crude protein and crude lipid, both of which are essential nutritious components. Our results show the capability of R. paludigena CM33 as a probiotic supplement in shrimp feed in improving growth, antimicrobial responses against VPAHPND, and meat quality by increasing protein and lipid content in shrimp.

Oyster-derived dipeptides RI, IR, and VR promote testosterone synthesis by reducing oxidative stress in TM3 cells

Short peptides have gained widespread utilization as functional constituents in the development of functional foods due to their remarkable biological activity. Previous investigations have established the positive influence of oysters on testosterone biosynthesis, although the underlying mechanism remains elusive. This study aims to assess the impact of three dipeptides derived from oysters on the oxidative stress state of TM3 cells induced by AAPH while concurrently examining alterations in cellular testosterone biosynthesis capacity. The investigation encompasses an analysis of reactive oxygen species (ROS) content, antioxidant enzyme activity, apoptotic status, and expression levels of crucial enzymes involved in the testosterone synthesis pathway within TM3 cells, thus evaluating the physiological activity of the three dipeptides. Additionally, molecular docking was employed to investigate the inhibitory activity of the three dipeptides against ACE. The outcomes of this study imply that the oxidative stress state of cells impedes the synthesis of testosterone by inhibiting the expression of essential proteins in the testosterone synthesis pathway. These three dipeptides derived from oysters ameliorate cellular oxidative stress by directly scavenging excess ROS or reducing ROS production rather than enhancing cellular antioxidant capacity through modulation of antioxidant enzyme activity. These findings introduce a novel avenue for developing and utilizing antioxidant peptides derived from food sources.

Multi-Omics Pipeline and Omics-Integration Approach to Decipher Plant's Abiotic Stress Tolerance Responses

The present day's ongoing global warming and climate change adversely affect plants through imposing environmental (abiotic) stresses and disease pressure. The major abiotic factors such as drought, heat, cold, salinity, etc., hamper a plant's innate growth and development, resulting in reduced yield and quality, with the possibility of undesired traits. In the 21st century, the advent of high-throughput sequencing tools, state-of-the-art biotechnological techniques and bioinformatic analyzing pipelines led to the easy characterization of plant traits for abiotic stress response and tolerance mechanisms by applying the 'omics' toolbox. Panomics pipeline including genomics, transcriptomics, proteomics, metabolomics, epigenomics, proteogenomics, interactomics, ionomics, phenomics, etc., have become very handy nowadays. This is important to produce climate-smart future crops with a proper understanding of the molecular mechanisms of abiotic stress responses by the plant's genes, transcripts, proteins, epigenome, cellular metabolic circuits and resultant phenotype. Instead of mono-omics, two or more (hence 'multi-omics') integrated-omics approaches can decipher the plant's abiotic stress tolerance response very well. Multi-omics-characterized plants can be used as potent genetic resources to incorporate into the future breeding program. For the practical utility of crop improvement, multi-omics approaches for particular abiotic stress tolerance can be combined with genome-assisted breeding (GAB) by being pyramided with improved crop yield, food quality and associated agronomic traits and can open a new era of omics-assisted breeding. Thus, multi-omics pipelines together are able to decipher molecular processes, biomarkers, targets for genetic engineering, regulatory networks and precision agriculture solutions for a crop's variable abiotic stress tolerance to ensure food security under changing environmental circumstances.

Antioxidant Nanozymes: Mechanisms, Activity Manipulation, and Applications

Antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase play important roles in the inhibition of oxidative-damage-related pathological diseases. However, natural antioxidant enzymes face some limitations, including low stability, high cost, and less flexibility. Recently, antioxidant nanozymes have emerged as promising materials to replace natural antioxidant enzymes for their stability, cost savings, and flexible design. The present review firstly discusses the mechanisms of antioxidant nanozymes, focusing on catalase-, superoxide dismutase-, and glutathione peroxidase-like activities. Then, we summarize the main strategies for the manipulation of antioxidant nanozymes based on their size, morphology, composition, surface modification, and modification with a metal-organic framework. Furthermore, the applications of antioxidant nanozymes in medicine and healthcare are also discussed as potential biological applications. In brief, this review provides useful information for the further development of antioxidant nanozymes, offering opportunities to improve current limitations and expand the application of antioxidant nanozymes.

Prospective of Indole-3-Acteic Acid (IAA) and Endophytic Microbe Bacillus subtilis Strain SSA4 in Paddy Seedlings Development and Ascorbate-Glutathione (AsA-GSH) Cycle Regulation to Mitigate NaCl Toxicity

Plant growth promoting endophytes significantly affected plant health. The present study demonstrates effect of endophytic isolate Bacillus subtilis strain SSA4 and exogenous Indole-3-acetic acid (IAA) on paddy seedlings growth parameters, photosynthetic pigments, photosynthesis, leaf gas exchange parameters, respiration, oxidative stress biomarkers and Ascorbate-Glutathione (AsA-GSH) cycle under different NaCl (0-300 mM) stresses. The Bacillus subtilis SSA4 was identified by 16S r-RNA gene sequence analyses and NCBI BLASTn tools. The B. subtilis SSA4 tolerated 1100 mM NaCl and produced IAA (42.15 µg m/L) at 300 mM NaCl stress. The paddy genotype (HUR 917) treated with exogenous IAA (21 µg m/L) and B. subtilis strain SSA4 egg cell based bioformulation was significantly affected seedlings physiology and biochemistry at lower (150 mM) and higher (300 mM) NaCl doses. In conclusion, co-inoculation found as effective green tool to mitigating salinity stress in paddy seedlings.

Effects of α-Fe2O3 nanoparticles and biochar on plant growth and fruit quality of muskmelon under cadmium stress

Cadmium pollution in farmland has become a global environmental problem, threatening ecological security and human health. Biochar is effective in remediation of soil pollution. However, high concentrations of biochar can inhibit plant growth, and low concentrations of biochar have limited mitigation effect on cadmium toxicity. Therefore, the combination of low-concentration biochar and other amendments is a promising approach to alleviate cadmium toxicity in plants and improve the safety of edible parts. In this study, muskmelon was selected as the research object, and different concentrations of α-Fe₂O₃ nanoparticles were used alone or combined with biochar to explore the effects of different treatments on muskmelon plants in cadmium-contaminated soil. The results showed that the combined application of 250 mg/kg α-Fe₂O₃ nanoparticles and biochar had a good effect on the repair of cadmium toxicity in muskmelon plants. Compared with cadmium treatment, its application increased plant height by 32.53%, cadmium transport factor from root to stem decreased by 32.95%, chlorophyll content of muskmelon plants increased by 14.27%, and cadmium content in muskmelon flesh decreased by 18.83%. Moreover, after plant harvest, soil available cadmium content in 250 mg/kg α-Fe₂O₃ nanoparticles and biochar combined treatment decreased by 31.18% compared with cadmium treatment. The results of this study provide an effective reference for the composite application of different exogenous amendments and a feasible idea for soil heavy metal remediation and mitigation of cadmium pollution in farmland.

Uncovering the Role of PdePrx12 Peroxidase in Enhancing Disease Resistance in Poplar Trees

Peroxidase (Prx)-related genes are reported to be involved in the metabolism of hydrogen peroxide (H2O2) in plants. Here, we found that the expression of the PdePrx12 gene was upregulated in wild-type (WT) poplar line NL895 infected with the pathogens Botryosphaeria dothidea strain 3C and Alternaria alternata strain 3E. The PdePrx12 gene was cloned in the poplar line NL895 and its overexpression (OE) and reduced-expression (RE) vectors were constructed. OE and RE transgenic lines were then generated. The H2O2 content in the leaves was measured by DAB staining and spectrophotometric analysis, and the data revealed that the OE line had a reduced H2O2 content, whereas the RE line had an increased H2O2 content. These transgenic and WT plants were also inoculated with the 3C/3E pathogens. The leaf area infected by pathogen 3C/3E was determined and the OE line was found to have a larger area of infection, whereas the RE line was found to have a smaller area of infection. This result suggested PdePRX12 is involved in disease resistance in poplar. Given these results, this study demonstrated that when poplar is infected by pathogens, the expression of PdePrx12 is inhibited, leading to an increase in H2O2 content, thereby enhancing disease resistance.

Antioxidant and Antiapoptotic Properties of n-Butanol Fraction the Acanthopanax senticosus Extracts in H2O2-RAW264.7 Cells and CCl4-Induced Liver Injury in Mice

The Acanthopanax senticosus has been shown to have a wide range of pharmacological activities, which are associated with health benefits, such as antioxidant, anti-inflammatory, and antiapoptotic properties. A previous study has shown that the n-butanol fraction of A. senticosus extract had the strongest antioxidant effect in vitro. This study aimed to investigate the effects that the n-butanol fraction of A. senticosus extract could relieve oxidative stress damage through antioxidant and antiapoptotic in the H₂O₂-stimulated RAW264.7 macrophages and the CCl₄-induced liver injury. The result showed that the n-butanol fraction extract could relieve damage by increasing the intracellular antioxidant enzymes (SOD) level, decreasing intracellular ROS and MDA levels, and regulating antioxidant and antiapoptotic-related gene expression levels. The morphological observation of HE, TUNE, and immunohistochemistry staining of liver tissue verified that the n-butanol fraction extract is though anti-oxidative and antiapoptotic to alleviate cellular oxidative damage. The RT-PCR assay showed that the Keap1-Nrf2-ARE and the Bax/Bcl-2 signaling pathway were related to the molecular mechanism of action. The experimental results show that Acanthopanax senticosus extract has a good effect in treating liver injury and enhancing the antioxidant capacity of the body.

Comprehensive physiological, transcriptomic, and metabolomic analyses reveal the synergistic mechanism of Bacillus pumilus G5 combined with silicon alleviate oxidative stress in drought-stressed Glycyrrhiza uralensis Fisch

Glycyrrhiza uralensis Fisch. is often cultivated in arid, semi-arid, and salt-affected regions that suffer from drought stress, which leads to the accumulation of reactive oxygen species (ROS), thus causing oxidative stress. Plant growth-promoting bacteria (PGPB) and silicon (Si) have been widely reported to be beneficial in improving the tolerance of plants to drought stress by maintaining plant ROS homeostasis. Herein, combining physiological, transcriptomic, and metabolomic analyses, we investigated the response of the antioxidant system of G. uralensis seedlings under drought stress to Bacillus pumilus (G5) and/or Si treatment. The results showed that drought stress caused the overproduction of ROS, accompanied by the low efficiency of antioxidants [i.e., superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), the ascorbate (AsA)-glutathione (GSH) pool, total carotenoids, and total flavonoids]. Inversely, supplementation with G5 and/or Si enhanced the antioxidant defense system in drought-stressed G. uralensis seedlings, and the complex regulation of the combination of G5 and Si differed from that of G5 or Si alone. The combination of G5 and Si enhanced the antioxidant enzyme system, accelerated the AsA-GSH cycle, and triggered the carotenoid and flavonoid metabolism, which acted in combination via different pathways to eliminate the excess ROS induced by drought stress, thereby alleviating oxidative stress. These findings provide new insights into the comparative and synergistic roles of PGPB and Si in the antioxidant system of plants exposed to drought and a guide for the application of PGPB combined with Si to modulate the tolerance of plants to stress.

Influence of Drought Stress on Physiological Responses and Bioactive Compounds in Chicory (Cichorium intybus L.): Opportunity for a Sustainable Agriculture

Food production from agriculture depends on irrigation, mainly in poor rainfall zones, such as the Mediterranean region. Chicory is an important food crop component of the Mediterranean diet. Considering the increasing incidence of drought due to climate change, this study was carried out in order to investigate the effect of moderate drought stress on photosynthesis, leaf gaseous exchange, growth, and tocol and carotenoid composition of chicory under field conditions. Chicory was subjected to rainfed condition stress in a randomized block design. At 50 days of treatment, drought stress caused about 48% reduction in dry matter, 30% in leaf relative water content, and about 25% in photosynthetic rate and stomatal conductance, whereas mesophyll conductance was not affected. A strong relationship between photosynthetic rates and stomatal conductance was observed. In the rainfed chicory, at the end of treatment, an increase (about 20%) in carotenoid and tocopherol content was found, thus, giving further insight into the positive effect of moderate drought stress on these compounds. This finding suggests that under proper rainfed conditions, it is possible to increase and save the quality of dry chicory, although yield loss occurs.

Cellular Antioxidant Properties of Ischnoderma Resinosum Polysaccharide

A predominant polysaccharide isolated from Ischnoderma resinosum underwent evaluation for its capacity to scavenge free radicals and its potential antioxidant properties at a cellular-oriented level. This proved that Ischnoderma resinosum polysaccharide (IRP) remarkably curtailed AAPH-induced erythrocyte hemolysis through the inhibition of the generation of ROS (p < 0.05). Rather, it caused the restoration of intracellular antioxidant enzyme (SOD, GSH-Px, and CAT) activities at an acceptable pace and the silencing of intracellular MDA formation, as well as the rescaling of LDH leakage. Furthermore, a model of oxidative stress in HepG2 cells was established by adopting 400 μM of hydrogen peroxide, which suggested that IRP manifests promising antioxidant activity. Notably, after the intervention of IRP in the H2O2-induced HepG2 cells, there was a statistical elevation in cell survivability (p < 0.05). IRP diminished the morphological alterations in the nucleus and decreased the secretion of ROS (p < 0.05), with a dose-dependent abrogation of apoptosis (p < 0.05). Consequently, IRP, which was isolated and purified, was able to scavenge free radicals and possessed favorable antioxidant activity that could dampen the occurrence of oxidative stimulation and effectively alleviate the AAPH-induced erythrocyte hemolysis and H2O2-induced oxidative damage in HepG2 cells. This provides a basis and theoretical reference for the development and utilization of IRP as a natural antioxidant, with emphasis on the exploitation of environmentally friendly and cost-effective antioxidants.

ZmNAC074, a maize stress-responsive NAC transcription factor, confers heat stress tolerance in transgenic Arabidopsis

The harsh environment such as high temperature greatly limits the growth, development and production of crops worldwide. NAC (NAM, ATAF1/2, and CUC2) transcription factors (TFs) play key regulatory roles in abiotic stress responses of plants. However, the functional roles of NAC TFs in heat stress response of maize remain elusive. In our present study, we identified and isolated a stress-responsive NAC transcription factor gene in maize, designated as ZmNAC074 and orthologous with rice OsNTL3. Further studies revealed that ZmNAC074 may encode a membrane-bound transcription factor (MTF) of NAC family in maize, which is comprised of 517 amino acid residues with a transmembrane domain at the C-terminus. Moreover, ZmNAC074 was highly expressed and induced by various abiotic stresses in maize seedlings, especially in leaf tissues under heat stress. Through generating ZmNAC074 transgenic plants, phenotypic and physiological analyses further displayed that overexpression of ZmNAC074 in transgenic Arabidopsis confers enhanced heat stress tolerance significantly through modulating the accumulation of a variety of stress metabolites, including reactive oxygen species (ROS), antioxidants, malondialdehyde (MDA), proline, soluble protein, chlorophyll and carotenoid. Further, quantitative real-time PCR analysis showed that the expression levels of most ROS scavenging and HSR- and UPR-associated genes in transgenic Arabidopsis were significantly up-regulated under heat stress treatments, suggesting that ZmNAC074 may encode a positive regulator that activates the expression of ROS-scavenging genes and HSR- and UPR-associated genes to enhance plant thermotolerance under heat stress conditions. Overall, our present study suggests that ZmNAC074 may play a crucial role in conferring heat stress tolerance in plants, providing a key candidate regulatory gene for heat stress tolerance regulation and genetic improvement in maize as well as in other crops.

From Soil Amendments to Controlling Autophagy: Supporting Plant Metabolism under Conditions of Water Shortage and Salinity

Crop resistance to environmental stress is a major issue. The globally increasing land degradation and desertification enhance the demand on management practices to balance both food and environmental objectives, including strategies that tighten nutrient cycles and maintain yields. Agriculture needs to provide, among other things, future additional ecosystem services, such as water quantity and quality, runoff control, soil fertility maintenance, carbon storage, climate regulation, and biodiversity. Numerous research projects have focused on the food–soil–climate nexus, and results were summarized in several reviews during the last decades. Based on this impressive piece of information, we have selected only a few aspects with the intention of studying plant–soil interactions and methods for optimization. In the short term, the use of soil amendments is currently attracting great interest to cover the current demand in agriculture. We will discuss the impact of biochar at water shortage, and plant growth promoting bacteria (PGPB) at improving nutrient supply to plants. In this review, our focus is on the interplay of both soil amendments on primary reactions of photosynthesis, plant growth conditions, and signaling during adaptation to environmental stress. Moreover, we aim at providing a general overview of how dehydration and salinity affect signaling in cells. With the use of the example of abscisic acid (ABA) and ethylene, we discuss the effects that can be observed when biochar and PGPB are used in the presence of stress. The stress response of plants is a multifactorial trait. Nevertheless, we will show that plants follow a general concept to adapt to unfavorable environmental conditions in the short and long term. However, plant species differ in the upper and lower regulatory limits of gene expression. Therefore, the presented data may help in the identification of traits for future breeding of stress-resistant crops. One target for breeding could be the removal and efficient recycling of damaged as well as needless compounds and structures. Furthermore, in this context, we will show that autophagy can be a useful goal of breeding measures, since the recycling of building blocks helps the cells to overcome a period of imbalanced substrate supply during stress adjustment.