An experiment was carried out to determine plant growth, mineral uptake, lipid peroxidation, antioxidative enzymes, and antioxidant of cucumber plants （Cucumis sativus L. cv. Xintaimici） under copper stress, either ...An experiment was carried out to determine plant growth, mineral uptake, lipid peroxidation, antioxidative enzymes, and antioxidant of cucumber plants （Cucumis sativus L. cv. Xintaimici） under copper stress, either ungrafted or grafted onto the rootstock （Cucurbitaficifolia）. Excess Cu inhibited growth, photosynthesis, and pigment synthesis of grafted and ungrafted cucumber seedlings and significantly increased accumulation of Cu in roots besides reducing mineral uptake. Cu concentration in roots of grafted cucumber plants was significantly higher than that of ungrafted plants and obviously lower in leaves. The accumulation of reactive oxygen species （ROS） significantly increased in cucumber leaves under Cu stress and resulted in lipid peroxidation, and the levels of ROS and lipid peroxidation were greatly decreased by grafting. Activities of protective enzymes （superoxide dismutase, SOD; peroxidase, POD; catalase, CAT; ascorbate peroxidase, APX; dehydroascorbate reductase, DHAR; glutathione reductase, GR） and the contents of ascorbate and glutathione in leaves of grafted plants were significantly higher than those of ungrafted plants under Cu stress. Better performance of grafted cucumber plants were attributed to the higher ability of Cu accumulation in their roots, better nutrient status, and the effective scavenging system of ROS.展开更多
Objective To investigate effects of glucose excursion on the oxidative/antioxidative system in subjects with different types of glucose regulation. Methods A total of 30 individuals with normal glucose regulation (NGR...Objective To investigate effects of glucose excursion on the oxidative/antioxidative system in subjects with different types of glucose regulation. Methods A total of 30 individuals with normal glucose regulation (NGR), 27 subjects with impaired glucose regulation (IGR) and 27 subjects with newly diagnosed type 2 diabetes mellitus (T2DM) were selected and recruited for 3 days’ continuous glucose monitor system (CGMS) assessment. The data from CGMS was used to calculate the mean amplitude of glycemic excursion (MAGE), mean blood glucose (MBG) and its standard deviation (SDBG), area under the ROC curve when the blood glucose 5.6 mmol/L within 24 h (AUC 5.6), mean of daily differences (MODD), and mean postprandial glucose excursion (MPPGE). In all groups, the content or activity of malondialdehyde (MDA), total antioxidation capacity (TAOC) and glutathione peroxidase (GSH‐Px) were detected. Results Glucose excursion parameters of subjects with T2DM or IGR were higher than those of NGR subjects (P0.05 or 0.01). Moreover, Glucose excursion parameters of T2DM subjects were higher than those of IGR subjects (P0.05 or 0.01). Subjects with T2DM or IGR had significant higher MDA levels and lower GSH‐Px/MDA and TAOC/MDA levels compared to NGR subjects (P0.01). T2DM subjects had even higher MDA levels and lower GSH‐Px/MDA levels than IGR (P0.05 or 0.01). According to the median of normal population for MAGE, T2DM and IGR subjects were divided into MAGE2.6mmol/L Group and MAGE≤2.6mmol/L Group. MAGE2.6mmol/L Group had higher levels of MDA and lower levels of GSH‐Px/MDA than MAGE≤2.6mmol/L Group (P0.05). There was no significant difference between the two groups (P0.05) in terms of the levels of TAOC/MDA. Pearson correlation analysis showed that MDA was positively correlated with FPG, 2hPG, MAGE, and SBP. GSH‐Px/MDA was negatively correlated with MAGE and TC. TAOC/MDA was negatively correlated with FPG. Partial correlation analysis showed that the relationship between MDA and MAGE, GSH‐Px/MDA, and MAGE remained significant after adjustments for the other differences among groups. Conclusion Glucose excursion contributed significantly to promoting lipid peroxidation and decreasing antioxidation capacity than chronic sustained hyperglycemia did in the subjects with different types of glucose regulation.展开更多
Drought is one of the major factors limiting the yield and quality of crops in the world. The activity of antioxidative system to tolerate the drought stress is significant in plants. In the present study, the activit...Drought is one of the major factors limiting the yield and quality of crops in the world. The activity of antioxidative system to tolerate the drought stress is significant in plants. In the present study, the activities and isoform profiles of catalase (CАТ), ascorbate peroxidase (APX), glutathione reductase (GR), and superoxide dismutase (SOD) were analyzed in four barley genotypes grown under soil water restriction. Drought stress caused increase in the activities of CАТ and SOD in all studied genotypes, while APX activity decreased. The total GR activity increased substantially in genotypes K 2778 and St.Garabag 7 and decreased in No. 77 local and St.Pallidum 596 genotypes under conditions of severe water stress. No detectable differences were observed in the isoenzyme pattern (the appearance of a new isoenzymes and disappearance of another one) between control plants and those subjected to soil drought. However, intensification of corresponding isoforms in electrophoretic spectra was observed in stressed barley leaves relative to watered ones. The obtained results possibly suggest that antioxidant protection in barley plants under drought conditions could be attributed mainly to SOD and CAT.展开更多
As a novel two-dimensional(2D)material,MXenes are anticipated to have a significant impact on future aqueous energy storage and conversion technologies owing to their unique intrinsic laminar structure and exceptional...As a novel two-dimensional(2D)material,MXenes are anticipated to have a significant impact on future aqueous energy storage and conversion technologies owing to their unique intrinsic laminar structure and exceptional physicochemical properties.Nevertheless,the fabrication and utilization of functional MXenebased devices face formidable challenges due to their susceptibility to oxidative degradation in aqueous solutions.This review begins with an outline of various preparation techniques for MXenes and their implications for structure and surface chemistry.Subsequently,the controversial oxidation mechanisms are discussed,followed by a summary of currently employed oxidation characterization techniques.Additionally,the factors influencing MXene oxidation are then introduced,encompassing chemical composition(types of M,X elements,layer numbers,terminations,and defects)as well as environment(atmosphere,temperature,light,potential,solution pH,free water and O_(2)content).The review then shifts its focus to strategies aiming to prevent or delay MXene oxidation,thereby expanding the applicability of MXenes in complex environments.Finally,the challenges and prospects within this rapidly-growing research field are presented to promote further advancements of MXenes in aqueous storage systems.展开更多
Neuroinflammation is an inflammatory response in the central nervous system associated with various neurological conditions.The inflammatory process is typically treated with non-steroidal and steroidal anti-inflammat...Neuroinflammation is an inflammatory response in the central nervous system associated with various neurological conditions.The inflammatory process is typically treated with non-steroidal and steroidal anti-inflammatory drugs,which have a range of serious adverse effects.As an alternative,naturally derived molecules such as quercetin and its derivatives show promising anti-inflammatory properties and beneficial effects on various physiological functions.Our objective was to synthesize the evidence on the anti-inflammatory effect of quercetin and its derivatives in in vivo models,in the face of neuroinflammatory insults induced by lipopolysaccharide,through a systematic review and meta-analysis.A search of the preclinical literature was conducted across four databases(Pub Med,Web of Science,Scielo,and Google Scholar).Studies were selected based on inclusion and exclusion criteria,assessed for methodological quality using CAMARADES,and risk of bias using the SYRCLE tool,and data were extracted from the studies.The quantitative assessment of quercetin effects on the expression of pro-inflammatory cytokines and microgliosis was performed through a meta-analysis.A total of 384 potentially relevant articles were identified,of which 11 studies were included in the analysis.The methodological quality was assessed,resulting in an average score of 5.8/10,and the overall risk of bias analysis revealed a lack of methodological clarity in most studies.Furthermore,through the meta-analysis,it was observed that treatment with quercetin statistically reduces pro-inflammatory cytokines,such as tumor necrosis factor alpha,interleukin 6,interleukin 1β(n=89;SMD=–2.00;95%CI:–3.29 to–0.71),and microgliosis(n=33;SMD=–2.56;95%CI:–4.07 to–1.10).In terms of underlying mechanisms,quercetin and its derivatives exhibit antioxidant and anti-apoptotic properties,possibly through the nuclear factor erythroid 2-related factor 2(Nrf2)/HO-1 pathways,increasing the expression of antioxidant enzymes and reducing reactive species,and modulating the caspase pathway,increasing levels of anti-apoptotic proteins and decreasing proapoptotic proteins.Quercetin and its derivatives exhibit highly pleiotropic actions that simultaneously contribute to preventing neuroinflammation.However,despite promising results in animal models,future directions should focus on well-designed clinical studies to assess the safety,bioavailability,and efficacy of quercetin and its derivatives in humans.Additionally,standardization of methods and dosages in studies is crucial to ensure consistency of findings and optimize their application in clinical settings.展开更多
Response of growth rate and antioxidative system of ten Bacillus strains to acid stresses was assayed.Strong acid treatment significantly decreased the growth rate of the strains.Acid stresses increased the GPX activi...Response of growth rate and antioxidative system of ten Bacillus strains to acid stresses was assayed.Strong acid treatment significantly decreased the growth rate of the strains.Acid stresses increased the GPX activity and GSSG content of the tested strains.Divergent changes occurred in ROS and antioxidative system(SOD,CAT,GR,MDA and GSH).Environmental changes including soil acidification exert obvi-ous stresses on soil ecosystems and influence soil microor-ganisms.In this study,ten microbial strains were incubated under different acid treatments to investigate responses of microbial growth and antioxidative system to acid stress.All the strains belong to Bacillus genus,but exhibit distinct ecological functions.We observed that these microbial strains had obviously different pH tolerance threshold,in spite of the close phylogenetic classification among strains.Acid stresses exerted significant effects on microbial antiox-idative system,including superoxide dismutase(SOD),cata-lase(CAT)and glutathione transferring enzymes(GPX and GR)and reactants(GSH and GSSH),but the effects were strain specific.Furthermore,we found acid stress effects on total variances of the investigated microbial antioxidative system along the first two principal components(PCs).Activities of CAT and SOD contributed substantially to PC1 that reflected obvious acid effects on NC7 and ZC4,and closely related to intracellular malondialdehyde content.The GSSG activities and GSH/GSSG contributed greatly to PC2 that unveiled acid stress effects on most of the microbial strains.Our results highlight substantially heterogeneous responses of microbial strains to acid stress and support that phylogenetic closeness does not imply functional similarity of soil microorganisms under environmental changes.展开更多
Microalgae,such as Chlorella vulgaris Beijerinck(green algae),are beneficial microscopic organisms that may help plants to improve nutrient uptake,growth,and abiotic tolerance to stressors.The current study was perfor...Microalgae,such as Chlorella vulgaris Beijerinck(green algae),are beneficial microscopic organisms that may help plants to improve nutrient uptake,growth,and abiotic tolerance to stressors.The current study was performed to investigate the effectiveness of algae(Chlorella vulgaris Beijerinck)foliar applications[1%,3%,or 5%(v/v)]on mitigation of drought stress in broccoli plants subjected to water deficit at 25%of field capacity.The results showed that the broccoli plants grown under drought stress alone exhibited severe disturbance in growth with considerable reductions in the shoot length,and fresh and dry weights,leaf area,relative water content,leaf water potential,and photosynthetic pigment contents and elevated levels of the lipid peroxidation product malondialdehyde in the leaves.Additionally,the foliar application of microalgae mitigated the detrimental effects of drought,leading to better growth performance(increase of 9%–132%)when compared with the drought-stressed plants that had not received an application of microalgae.Microalgae-mediated beneficial effects were particularly evident in the enhancement of the photosynthetic pigment contents,including chlorophyll-a(6%–60%),chlorophyll-b(19%–55%),and total carotenoids(26%–114%).Exogenous microalgae also contributed to the reduction of membrane damage,as proven by significantly decreased levels of malondialdehyde(10%–39%)in the leaves of the broccoli plants exposed to drought stress.The application of microalgae increased the total flavonoid and phenolic contents,and nutrition uptake.Furthermore,the activities of enzymatic antioxidants like ascorbate peroxidase,catalase,glutathione reductase,and superoxide dismutase increased in response to mediation,resulting in significant alleviation of drought-induced oxidative damage.The most effective application concentration of microalgae was determined as 5%.Overall investigations revealed that the foliar application of microalgae could be recommended as a sustainable strategy to improve the defense system of drought-stressed broccoli plants.展开更多
Endophytic bacteria are promising bacterial fertilizers to improve plant growth under adverse environment.For ecological remediation of coastal wetlands,it was necessary to investigate the effect and interaction of en...Endophytic bacteria are promising bacterial fertilizers to improve plant growth under adverse environment.For ecological remediation of coastal wetlands,it was necessary to investigate the effect and interaction of endophytes on halophytes under saline-alkali stress.In this study,an endophytic bacterium strain HK1 isolated from halophytes was selected to infect Suaeda glauca under pH(7 and 8)and salinity gradient(150,300 and 450mmolL^(-1)).Strain HK1 was identified as Pantoea ananatis and it had ability to fix nitrogen,dissolve inorganic phosphorus and produce indole-3-aceticacid(IAA).The results showed that strain HK1 could promote the growth of S.glauca seedings when the salinity was less than 300mmolL^(-1),in view of longer shoot length and heavier fresh weight.The infected plants could produce more proline to decrease the permeability of cells,which content increased by 26.2%–61.1%compared to the non-infected group.Moreover,the oxidative stress of infected plants was relieved with the malondialdehyde(MDA)content decreased by 16.8%–32.9%,and the peroxidase(POD)activity and catalase(CAT)activity increased by 100%–500%and 6.2%–71.4%,respectively.Statistical analysis revealed that increasing proline content and enhancing CAT and POD activities were the main pathways to alleviate saline-alkali stress by strain HK1 infection,and the latter might be more important.This study illustrated that endophytic bacteria could promote the growth of halophytes by regulation of osmotic substances and strengthening antioxidant activities.This finding would be helpful for the bioremediation of coastal soil.展开更多
Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairme...Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairments is essential for the long-term production of sweetpotatoes.Melatonin has been recognised for its capacity to assist plants in dealing with abiotic stress conditions.This research aimed to investigate how different doses of exogenous melatonin influence heat damage in sweetpotato plants.Heat stress drastically affected shoot and root fresh weight by 31.8 and 44.5%,respectively.This reduction resulted in oxidative stress characterised by increased formation of hydrogen peroxide(H_(2)O_(2))by 804.4%,superoxide ion(O_(2)^(·-))by 211.5%and malondialdehyde(MDA)by 234.2%.Heat stress also reduced chlorophyll concentration,photosystemⅡefficiency(F_v/F_m)by 15.3%and gaseous exchange.However,pre-treatment with 100μmol L^(-1)melatonin increased growth and reduced oxidative damage to sweetpotato plants under heat stress.In particular,melatonin decreased H_(2)O_(2),O_(2)^(·-)and MDA by 64.8%,42.7%and 38.2%,respectively.Melatonin also mitigated the decline in chlorophyll levels and improved stomatal traits,gaseous exchange and F_(v)/F_(m)(13%).Results suggested that the favorable outcomes of melatonin treatment can be associated with elevated antioxidant enzyme activity and an increase in non-enzymatic antioxidants and osmo-protectants.Overall,these findings indicate that exogenous melatonin can improve heat stress tolerance in sweetpotatoes.This stu dy will assist re searchers in further investigating how melatonin makes sweetpotatoes more resistant to heat stress.展开更多
Nickel(Ni)toxicity significantly impairs plant growth,photosynthesis,and metabolism by inducing oxidative stress.This study evaluates the potential of exogenous Alpha-Ketoglutarate(AKG)in mitigating Ni-induced stress ...Nickel(Ni)toxicity significantly impairs plant growth,photosynthesis,and metabolism by inducing oxidative stress.This study evaluates the potential of exogenous Alpha-Ketoglutarate(AKG)in mitigating Ni-induced stress in Peganum harmala L.Seedlings were exposed to 0,200,500,and 750μM NiCl2,with or without AKG supplementation.Under 750μM Ni stress,dry weight(DW)decreased by 33.7%,tissue water content(TWC)by 39.9%,and chlorophyll a and total chlorophyll levels were reduced by 17%and 15%,respectively.Ni exposure also significantly increased secondary metabolite production,with leaf anthocyanin content rising by 131%,and superoxide dismutase(SOD)and catalase(CAT)activities increasing by 228%and 53%,respectively,in roots at 500μM Ni.AKG treatment alleviated Ni toxicity by enhancing TWC by 39%and promoting root and shoot growth.Additionally,AKG treatment boosted the synthesis of phenolic compounds and flavonoids,contributing to improved tolerance against Ni stress.These findings demonstrate the potential of AKG in enhancing Ni tolerance in P.harmala,suggesting its promising role in bioremediation of metal-contaminated soils.This is the first study to report the beneficial effects of exogenous AKG in alleviating nickel toxicity in P.harmala L.,offering a new approach for improving plant resilience to heavy metal stress.展开更多
Salt stress is a major threat to crop agricultural productivity.Salinity affects plants’physiological and biochemical functions by hampering metabolic functions and decreasing photosynthetic rates.Salinity causes hyp...Salt stress is a major threat to crop agricultural productivity.Salinity affects plants’physiological and biochemical functions by hampering metabolic functions and decreasing photosynthetic rates.Salinity causes hyperosmotic and hyperionic stress,directly impairing plant growth.In this study,eggplant seeds primed with moringa leaf extract(5%,10%,and 15%),nano-titaniumdioxide(0.02%,0.04%,and 0.06%),and ascorbic acid(0.5,1,and 2 mM)at different NaCl salt(0,75,and 150 mM)concentration were grown.The germination attributes(final germination percentage,germination index,mean germination time,and mean germination rate)and growth(root length,shoot length,fresh biomass,and dry biomass)were enhanced in the primed seedlings by the different priming agents,more prominently in ascorbic acid primed seedlings.The accumulation of hydrogen peroxide was greater in seedlings with higher salt levels.Similarly,the activity of antioxidant enzymes(superoxide dismutase,peroxidase,and catalase)was higher in primed seedlings compared to the control.At 150 mM,the antioxidant capacity was higher than 75 mM,and the seedlings’sodiumand chloride content was higher.The results demonstrate that seedling germination,growth,and activity of the antioxidant enzymes in ascorbic acid-primed seedlings increase their tolerance to salinity.Therefore,using different ascorbic acid concentrations(0.5,1,and 2 mM)as a priming agent to enhance germination and growth in saline conditions has proven effective.展开更多
Objective:To investigate the mechanisms by which unripe papaya extract(UCP)protects skin keratinocytes from UVB-induced inflammation and apoptosis.Methods:High-performance liquid chromatography was used to identify th...Objective:To investigate the mechanisms by which unripe papaya extract(UCP)protects skin keratinocytes from UVB-induced inflammation and apoptosis.Methods:High-performance liquid chromatography was used to identify the phytochemical composition of UCP.The free radical scavenging capacity of UCP was assessed against O_(2)·^(-),and H2O2.HaCaT cells were pre-treated with varying concentrations of UCP and exposed to 40 mJ/cm2 UVB radiation.Cell viability,reactive oxygen species(ROS)levels,apoptotic markers,and inflammatory mediators were evaluated using standard biochemical assays and molecular techniques.Results:UCP treatment significantly improved cell viability and reduced intracellular ROS and the release of O_(2)·^(-)and H2O2.UCP also inhibited apoptosis,as evidenced by reduced cytochrome c release and suppression of Akt phosphorylation.Additionally,UCP exhibited anti-inflammatory effects by downregulating COX-2 expression,suppressing PGE2 release,and inhibiting c-Jun and NF-κB signaling pathways.Conclusions:UCP effectively protects skin keratinocytes from UVB-induced oxidative stress,inflammation,and apoptosis.These findings support its potential as a natural therapeutic agent for preventing UV-related skin damage.However,in vivo studies are warranted to confirm its efficacy.展开更多
Heavy metal pollution has become a pervasive environmental issue affecting numerous regions worldwide.Recently,there has been significant attention given to the application of nano-enabled technologies with the purpos...Heavy metal pollution has become a pervasive environmental issue affecting numerous regions worldwide.Recently,there has been significant attention given to the application of nano-enabled technologies with the purpose of enhancing plant development and alleviating heavy metal stress.This study aimed to illustrate the potential of zinc oxide nanoparticles(ZnO-NPs)to enhance the morphological traits of D.huoshenense exposed to cadmium(Cd)stress.The chemical structure and elemental composition of the ZnO-NPs were characterised by a series of analytical methods,including X-ray diffraction,UV-Vis spectrometry,XPS,andTEM.Plant samples usedwere collected at 0,5,and 15 days in order to assess physiological and biochemical parameters under different Cd treatments.ZnONPs administered in pot experiments have been shown to enhance plant proliferation through the modulation of Cd enrichment levels.The results revealed that ZnO-NPs enhanced plant growth by increasing soluble sugars and proline levels,enhancing activities of antioxidant enzymes(SOD,POD,CAT,APX)and reducing electrolyte leakage(EL)and malondialdehyde(MDA)content.Furthermore,ZnO-NPs enhanced the net photosynthetic rate,transpiration,stomatal conductance,and chlorophyll content in leaves subjected to Cd stress at the 10-day sampling stage.Exogenous ZnO-NPs significantly elevated the expression of genes associated with flavonoid biosynthesis,potentially facilitating the accumulation of medicinal compounds to mitigate Cd stress.Taken together,these findings provide a novel perspective on the strategies employed by medicinal plants in response to Cd.展开更多
Cerium oxide nanoparticles(CeO_(2)NPs)have attracted great interest recently in the field of cosmetics due to their excellent biomedical properties to treat diseases caused by reactive oxygen species(ROS).However,a re...Cerium oxide nanoparticles(CeO_(2)NPs)have attracted great interest recently in the field of cosmetics due to their excellent biomedical properties to treat diseases caused by reactive oxygen species(ROS).However,a realizable synthesis approach for the large-scale synthesis of CeO_(2)NPs reaching the quality requirements of cosmetic grade is still in desperate demand.This work reports a robust solvothermal approach for the mass production of self-assembled CeO_(2)microsphere(SA CeO_(2))up to 1000 g at a time.Depending on the concentration of initial precursors,the re sulting particle sizes can be precisely tuned to obtain micro spherical samples of SA CeO_(2)-145 nm,SA CeO_(2)-420 nm and SA CeO_(2)-680 nm.Typically,the mesoporous SA CeO_(2)-420 nm with the largest specific surface area exhibits greatly enhanced number of oxygen vacancies(Ce^(3+)cations)proved by X-ray photoelectro n spectro scopy and electron paramagnetic resonance analysis.Moreover,Turbiscan stability test reveals the superior physical stability of SA CeO_(2)-420 nm suspension based on multiple light scattering technology,which contributes to reduced in-vitro cytotoxicity assessed via MTT viability assay.Therefore,SA CeO_(2)-420 nm exhibits excellent antioxidant performance with a high DPPH free radical scavenging ratio of more than 90% at a low concentration below 1 mg/mL.Importantly,SA CeO_(2)-420 nm can effectively inhibit the in-vitro release of reactive oxygen species in mitochondria caused by UVB irradiation in HaCaT cells,exerting good antioxidant activity at the cellular level.As a consequence,a significant increase in skin color and brightness can be observed after 28 d of application of the emulsion containing SA CeO_(2)-420 nm,demonstrating the potential whitening effect.This work provides a facile and readily scalable synthetic strategy of CeO_(2)microsphere and subsequently offers an innovative avenue for their cosmetic application.展开更多
[Objectives]This study was conducted to investigate the regulatory effects of selenium(Se)on the content and balance of endogenous hormones and the function of antioxidant system during seed development in Red sandalw...[Objectives]This study was conducted to investigate the regulatory effects of selenium(Se)on the content and balance of endogenous hormones and the function of antioxidant system during seed development in Red sandalwood(Pterocarpus santalinus).[Methods]Two basic treatments,seven single-fertilization treatments,and four combined fertilization treatments were designed.Sampling was conducted at 2,5,8,and 18 weeks after flower withering to measure the embryo abortion percentage(EAP),the contents of three endogenous hormones(IAA,GA_(3),ABA),and the activities of four antioxidant enzymes(CAT,APX,SOD,GR).[Results]Se application significantly inhibited embryo abortion in Red sandalwood,with Na_(2)SeO_(3)[Se(IV)]showing superior effects to Na_(2)SeO_(3)(Se(VI))and far exceeding the efficacy of individual applications of KCl,H_(3)BO_(3),CO(NH_(2))_(2),Ca(H_(2)PO_(4))_(2),NPK compound fertilizer,or EFOF.The combined treatment of Se with NPK compound fertilizer and EFOF[EFOF+NPK compound fertilizer+Se(IV)]was the most effective,reducing the abortion percentage by 77.8%compared with UMC at 18 weeks after flower withering.Se application significantly increased the levels of three endogenous hormones and the(IAA+GA_(3))/ABA ratio in Red sandalwood seeds(including the embryonic stage).In the optimal treatment,the(IAA+GA_(3))content was 240.7%,256.4%,353.7%,and 502.9%higher than that of UMC at 2,5,8,and 18 weeks after flower withering,respectively.Se application also concurrently enhanced antioxidant enzyme activities,with all four antioxidant enzymes in seeds of Se-treated plants showing significant increases.Notably,the selenoenzyme GR maintained considerably high activity even at 18 weeks after flower withering.The EAP was highly significantly negatively correlated with IAA content and GR activity,identifying IAA and(IAA+GA_(3))content as key hormonal indicators and GR as the core antioxidant enzyme,together constituting the central regulatory factors.The results indicate that Se suppresses embryo abortion in Red sandalwood through a dual regulatory pathway:by elevating IAA and GA_(3)levels along with the(IAA+GA_(3))/ABA ratio to optimize hormonal signaling networks,and by enhancing the activities of antioxidant enzymes such as GR to alleviate oxidative stress induced by cool-season low temperatures.[Conclusions]This study provides a theoretical basis and technical strategy for precision fertilization and stress resistance management in the cultivation of Red sandalwood.展开更多
[Objective] The mitigative effect of antioxidase system of a rice mutant with low chlorophyll b on photooxidative damage was studied.[Method] A rice mutant with low chlorophyll b and its wild type were taken as experi...[Objective] The mitigative effect of antioxidase system of a rice mutant with low chlorophyll b on photooxidative damage was studied.[Method] A rice mutant with low chlorophyll b and its wild type were taken as experimental materials to comparatively research their peroxide (H2O2) contents, the activity and isozymes of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in chloroplast.[Result] Compared with the wild type, there were many kinds of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant, and the activity of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant was also correspondingly higher. Under intense light condition, the H2O2 content of chloroplast in mutant was less than that in the wild type. [Conclusion] The higher activity of scavenging active oxygen can relieve the photooxidative damage made by excessive light energy of intense light on photosynthetic membrane, which is an important reason for higher photosystem Ⅱ (PS II) stability of this mutant.展开更多
This article aims to study the effects of exogenous 24-epibrassinolide （EBR） on the changes in ROS, activities of antioxidative enzymes and antioxidants in cucumber （Cucumis sativus L.） seedling roots under hypoxi...This article aims to study the effects of exogenous 24-epibrassinolide （EBR） on the changes in ROS, activities of antioxidative enzymes and antioxidants in cucumber （Cucumis sativus L.） seedling roots under hypoxia stress. Seedlings of a hypoxiaresistant cultivar, Lühachun 4, and a hypoxia-sensitive cultivar, Zhongnong 8, were hydroponically grown for 8 d in normoxic or hypoxic nutrient solutions that were added or not added with 10^-3 mg L^-1 EBR. Under hypoxia stress, the ROS levels and the lipid peroxidation were significantly increased in the roots upon exposure to hypoxia stress, which were inhibited by EBR application. The EBR treatment significantly increased the seedlings growth and SOD, APX, GR activities, and contents of AsA and GSH under hypoxia stress. From the results obtained in this study, it can be concluded that oxidative damage on seedling roots by hypoxia stress can be considerably alleviated and the tolerance of plants was elevated.展开更多
[Objective] The aim was to understand defense mechanism of pear after inoculated Botryosphaeria berengeriana f. sp. piricolan and mechanism of antioxidant enzymes of biocontrol bacteria. [Method] Pears were treated by...[Objective] The aim was to understand defense mechanism of pear after inoculated Botryosphaeria berengeriana f. sp. piricolan and mechanism of antioxidant enzymes of biocontrol bacteria. [Method] Pears were treated by Botryosphaeria berengeriana f. sp. piricolan and bio control bacteria, and the change of antioxidant enzymes were determined. [Result] The biocontrol bacteria had little effect on MDA;the content of MDA treated by B. berengeriana reached high peak in 48 h, was 10.22nmol/g which was 1.86 times of CK; the content of MDA treated by B. berengeriana and biocontrol bacteria reached high peak in 24 h, was 8.92 nmol/g which was1.62 times of CK. The content of SOD treated by biocontrol bacteria reached high peak in 48 h, was 126.69 U/[g（FW）·min] which was 1.54 times of CK; the contents of SOD treated by B. berengeriana as well as B. berengeriana and biocontrol bacteria reached high peak in 24 h, were 122.10 and 135.32 U/[g（FW）·min] which were 1.48 and 1.65 times of CK respectively; the contents of POD on biocontrol bacteria treatment, B. ana treatment as well as B. berengeriana and biocontrol bacteria treatment reached high peak in 24 h, were 385.34, 342.50 and 290.00 U/[g（FW）·min] which were 1.83, 1.62 and 1.38 times of CK respectively. The contents of CAT on biocontrol bacteria treatment, B. rengeriana treatment as well as B. berengeriana and biocontrol bacteria treatment reached high peak in 6 h, were 133.33,114.17 and 113.35 U/[g（FW）·min] which were 1.33, 1.14 and 1.13 times of CK respectively. The biocontrol bacteria had little difference in CK; the content of PPO of B. berengeriana treatment reached high peak in 12 h, was 81.86 U/[g（FW）·min]which was 1.76 times of CK; B. berengeriana and biocontrol bacteria treatment reached high peak in 24 h, was 70.00 U/[g（FW）·min] which was 1.50 times of CK.[Conclusion] B. berengeriana and biocontrol bacteria had more effect on MDA; both B. berengeriana and biocontrol bacteria could increase the excitation of SOD enzyme activity; both B. berengeriana and biocontrol bacteria could increase the excitation of POD enzyme activity; both B. berengeriana and biocontrol bacteria could increase the excitation of CAT enzyme activity; using biocontrol bacteria alone had not obvious effect on PPO, B. berengeriana could increase the excitation of PPO enzyme activity.展开更多
By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechan...By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents.展开更多
This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide...This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide （H2O2） will alleviate NO2-caused injury. Twenty-eight-day-old B. campestris plants sprayed with 10 mmol L^-1 H2O2 aqueous solution （corresponding to approximate 1.0 mg H2O2 per single plant） were exposed to different concentrations of NO2 （0.25, 0.5, 1.0, and 2.0 μL L^-1, respectively） for 24 h under controlled environment. To measure the plant biomass, the plants were fumigated with the same NO2 concentrations as mentioned above for 7 h per day （8.00-15.00） for 7 days. As a control, charcoal filtered air alone was applied. Data were collected on plant biomass, total chlorophyll, photosynthetic rate, stomatal conductance, nitrate and nitrate reductase （NR）, antioxidative enzymes, ascorbate （ASA）, and malondialdehyde （MDA）, immediately after exposure. The results showed that exposure to a moderate dose of NO2 （e.g., 0.25 μL L^-1） had a favorable effect on plants, and the dry weight of the above-ground part increased, whereas the exposure to high NO2 concentrations （e.g., 0.5 μL L^-1 or higher） caused a reduction in the plant biomass and the total chlorophyll, when compared with the control. In addition, at 0.5 μL L^-1 or higher NO2 concentrations, prominent increases in the MDA level and superoxide dismutase （SOD） and NR activities were observed. Exposure to 1 μL L^-1 and higher NO2 resulted in necroses appearing on older leaves, and an increase in catalase （CAT） activity, decrease in ASA content, increased accumulation of NO3^-, and reduction in photosynthesis, when compared with the controls. No changes were detected in stomatal conductance under NO2 fumigation. The pretreatment with 10 mmol L^-1 H2O2 alleviated significantly NO2- caused biomass decrease and photosynthetic inhibition when compared with H2O2-untreated plants. Under NO2 fumigation, further induction in SOD and CAT activities occurred in H2O2 treated plants when compared with H2O2- untreated plants. The effect of NO2 on the ASA and MDA contents was also absent in H2O2-treated plants. However, the H2O2 treatment did not alter the nitrate content and NR activity in plants under NO2 fumigation. The H2O2 treatment caused a lower rate of stomatal conductance. Taken together, these data suggest that fumigation with an acute level of NO2 causes oxidative damage to B. campestris seedlings. The H2O2 pretreatment markedly protects plants against NO2 stress and this may be associated with inducible antioxidative level. NO2 fumigation contributes, at least in part, to the enhanced levels of nitrate in B. campestris leaves.展开更多
基金supported by the Young Scientist Innovation Science of Shandong Agricultural University,China (23653)
文摘An experiment was carried out to determine plant growth, mineral uptake, lipid peroxidation, antioxidative enzymes, and antioxidant of cucumber plants （Cucumis sativus L. cv. Xintaimici） under copper stress, either ungrafted or grafted onto the rootstock （Cucurbitaficifolia）. Excess Cu inhibited growth, photosynthesis, and pigment synthesis of grafted and ungrafted cucumber seedlings and significantly increased accumulation of Cu in roots besides reducing mineral uptake. Cu concentration in roots of grafted cucumber plants was significantly higher than that of ungrafted plants and obviously lower in leaves. The accumulation of reactive oxygen species （ROS） significantly increased in cucumber leaves under Cu stress and resulted in lipid peroxidation, and the levels of ROS and lipid peroxidation were greatly decreased by grafting. Activities of protective enzymes （superoxide dismutase, SOD; peroxidase, POD; catalase, CAT; ascorbate peroxidase, APX; dehydroascorbate reductase, DHAR; glutathione reductase, GR） and the contents of ascorbate and glutathione in leaves of grafted plants were significantly higher than those of ungrafted plants under Cu stress. Better performance of grafted cucumber plants were attributed to the higher ability of Cu accumulation in their roots, better nutrient status, and the effective scavenging system of ROS.
基金supported by the Shanghai United Developing Technology Project of Municipal Hospitals (SHDC12006101)the Health Bureau of Zhejiang Province (2009B091)
文摘Objective To investigate effects of glucose excursion on the oxidative/antioxidative system in subjects with different types of glucose regulation. Methods A total of 30 individuals with normal glucose regulation (NGR), 27 subjects with impaired glucose regulation (IGR) and 27 subjects with newly diagnosed type 2 diabetes mellitus (T2DM) were selected and recruited for 3 days’ continuous glucose monitor system (CGMS) assessment. The data from CGMS was used to calculate the mean amplitude of glycemic excursion (MAGE), mean blood glucose (MBG) and its standard deviation (SDBG), area under the ROC curve when the blood glucose 5.6 mmol/L within 24 h (AUC 5.6), mean of daily differences (MODD), and mean postprandial glucose excursion (MPPGE). In all groups, the content or activity of malondialdehyde (MDA), total antioxidation capacity (TAOC) and glutathione peroxidase (GSH‐Px) were detected. Results Glucose excursion parameters of subjects with T2DM or IGR were higher than those of NGR subjects (P0.05 or 0.01). Moreover, Glucose excursion parameters of T2DM subjects were higher than those of IGR subjects (P0.05 or 0.01). Subjects with T2DM or IGR had significant higher MDA levels and lower GSH‐Px/MDA and TAOC/MDA levels compared to NGR subjects (P0.01). T2DM subjects had even higher MDA levels and lower GSH‐Px/MDA levels than IGR (P0.05 or 0.01). According to the median of normal population for MAGE, T2DM and IGR subjects were divided into MAGE2.6mmol/L Group and MAGE≤2.6mmol/L Group. MAGE2.6mmol/L Group had higher levels of MDA and lower levels of GSH‐Px/MDA than MAGE≤2.6mmol/L Group (P0.05). There was no significant difference between the two groups (P0.05) in terms of the levels of TAOC/MDA. Pearson correlation analysis showed that MDA was positively correlated with FPG, 2hPG, MAGE, and SBP. GSH‐Px/MDA was negatively correlated with MAGE and TC. TAOC/MDA was negatively correlated with FPG. Partial correlation analysis showed that the relationship between MDA and MAGE, GSH‐Px/MDA, and MAGE remained significant after adjustments for the other differences among groups. Conclusion Glucose excursion contributed significantly to promoting lipid peroxidation and decreasing antioxidation capacity than chronic sustained hyperglycemia did in the subjects with different types of glucose regulation.
文摘Drought is one of the major factors limiting the yield and quality of crops in the world. The activity of antioxidative system to tolerate the drought stress is significant in plants. In the present study, the activities and isoform profiles of catalase (CАТ), ascorbate peroxidase (APX), glutathione reductase (GR), and superoxide dismutase (SOD) were analyzed in four barley genotypes grown under soil water restriction. Drought stress caused increase in the activities of CАТ and SOD in all studied genotypes, while APX activity decreased. The total GR activity increased substantially in genotypes K 2778 and St.Garabag 7 and decreased in No. 77 local and St.Pallidum 596 genotypes under conditions of severe water stress. No detectable differences were observed in the isoenzyme pattern (the appearance of a new isoenzymes and disappearance of another one) between control plants and those subjected to soil drought. However, intensification of corresponding isoforms in electrophoretic spectra was observed in stressed barley leaves relative to watered ones. The obtained results possibly suggest that antioxidant protection in barley plants under drought conditions could be attributed mainly to SOD and CAT.
基金supported by the Fundamental Research Funds for the Central Universities(No.2042023kf0094)the National Key Research and Development Program of China(No.2022YFA1502902)the National Natural Science Foundation of China(No.22101217).
文摘As a novel two-dimensional(2D)material,MXenes are anticipated to have a significant impact on future aqueous energy storage and conversion technologies owing to their unique intrinsic laminar structure and exceptional physicochemical properties.Nevertheless,the fabrication and utilization of functional MXenebased devices face formidable challenges due to their susceptibility to oxidative degradation in aqueous solutions.This review begins with an outline of various preparation techniques for MXenes and their implications for structure and surface chemistry.Subsequently,the controversial oxidation mechanisms are discussed,followed by a summary of currently employed oxidation characterization techniques.Additionally,the factors influencing MXene oxidation are then introduced,encompassing chemical composition(types of M,X elements,layer numbers,terminations,and defects)as well as environment(atmosphere,temperature,light,potential,solution pH,free water and O_(2)content).The review then shifts its focus to strategies aiming to prevent or delay MXene oxidation,thereby expanding the applicability of MXenes in complex environments.Finally,the challenges and prospects within this rapidly-growing research field are presented to promote further advancements of MXenes in aqueous storage systems.
基金supported by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)[Finance Code 001](to MGS)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico(CNPq)fellowship[research grants 309840/2022-8]。
文摘Neuroinflammation is an inflammatory response in the central nervous system associated with various neurological conditions.The inflammatory process is typically treated with non-steroidal and steroidal anti-inflammatory drugs,which have a range of serious adverse effects.As an alternative,naturally derived molecules such as quercetin and its derivatives show promising anti-inflammatory properties and beneficial effects on various physiological functions.Our objective was to synthesize the evidence on the anti-inflammatory effect of quercetin and its derivatives in in vivo models,in the face of neuroinflammatory insults induced by lipopolysaccharide,through a systematic review and meta-analysis.A search of the preclinical literature was conducted across four databases(Pub Med,Web of Science,Scielo,and Google Scholar).Studies were selected based on inclusion and exclusion criteria,assessed for methodological quality using CAMARADES,and risk of bias using the SYRCLE tool,and data were extracted from the studies.The quantitative assessment of quercetin effects on the expression of pro-inflammatory cytokines and microgliosis was performed through a meta-analysis.A total of 384 potentially relevant articles were identified,of which 11 studies were included in the analysis.The methodological quality was assessed,resulting in an average score of 5.8/10,and the overall risk of bias analysis revealed a lack of methodological clarity in most studies.Furthermore,through the meta-analysis,it was observed that treatment with quercetin statistically reduces pro-inflammatory cytokines,such as tumor necrosis factor alpha,interleukin 6,interleukin 1β(n=89;SMD=–2.00;95%CI:–3.29 to–0.71),and microgliosis(n=33;SMD=–2.56;95%CI:–4.07 to–1.10).In terms of underlying mechanisms,quercetin and its derivatives exhibit antioxidant and anti-apoptotic properties,possibly through the nuclear factor erythroid 2-related factor 2(Nrf2)/HO-1 pathways,increasing the expression of antioxidant enzymes and reducing reactive species,and modulating the caspase pathway,increasing levels of anti-apoptotic proteins and decreasing proapoptotic proteins.Quercetin and its derivatives exhibit highly pleiotropic actions that simultaneously contribute to preventing neuroinflammation.However,despite promising results in animal models,future directions should focus on well-designed clinical studies to assess the safety,bioavailability,and efficacy of quercetin and its derivatives in humans.Additionally,standardization of methods and dosages in studies is crucial to ensure consistency of findings and optimize their application in clinical settings.
基金funded by the National Natural Science Foundation of China(Grant Nos.U1701236 and 32071641)the Joint Team Project of Guangdong Laboratory for Lingnan Modern Agriculture(Grant No.NT2021010)Guangdong Science and Technology Department(Grant No.2021A1515012507).
文摘Response of growth rate and antioxidative system of ten Bacillus strains to acid stresses was assayed.Strong acid treatment significantly decreased the growth rate of the strains.Acid stresses increased the GPX activity and GSSG content of the tested strains.Divergent changes occurred in ROS and antioxidative system(SOD,CAT,GR,MDA and GSH).Environmental changes including soil acidification exert obvi-ous stresses on soil ecosystems and influence soil microor-ganisms.In this study,ten microbial strains were incubated under different acid treatments to investigate responses of microbial growth and antioxidative system to acid stress.All the strains belong to Bacillus genus,but exhibit distinct ecological functions.We observed that these microbial strains had obviously different pH tolerance threshold,in spite of the close phylogenetic classification among strains.Acid stresses exerted significant effects on microbial antiox-idative system,including superoxide dismutase(SOD),cata-lase(CAT)and glutathione transferring enzymes(GPX and GR)and reactants(GSH and GSSH),but the effects were strain specific.Furthermore,we found acid stress effects on total variances of the investigated microbial antioxidative system along the first two principal components(PCs).Activities of CAT and SOD contributed substantially to PC1 that reflected obvious acid effects on NC7 and ZC4,and closely related to intracellular malondialdehyde content.The GSSG activities and GSH/GSSG contributed greatly to PC2 that unveiled acid stress effects on most of the microbial strains.Our results highlight substantially heterogeneous responses of microbial strains to acid stress and support that phylogenetic closeness does not imply functional similarity of soil microorganisms under environmental changes.
文摘Microalgae,such as Chlorella vulgaris Beijerinck(green algae),are beneficial microscopic organisms that may help plants to improve nutrient uptake,growth,and abiotic tolerance to stressors.The current study was performed to investigate the effectiveness of algae(Chlorella vulgaris Beijerinck)foliar applications[1%,3%,or 5%(v/v)]on mitigation of drought stress in broccoli plants subjected to water deficit at 25%of field capacity.The results showed that the broccoli plants grown under drought stress alone exhibited severe disturbance in growth with considerable reductions in the shoot length,and fresh and dry weights,leaf area,relative water content,leaf water potential,and photosynthetic pigment contents and elevated levels of the lipid peroxidation product malondialdehyde in the leaves.Additionally,the foliar application of microalgae mitigated the detrimental effects of drought,leading to better growth performance(increase of 9%–132%)when compared with the drought-stressed plants that had not received an application of microalgae.Microalgae-mediated beneficial effects were particularly evident in the enhancement of the photosynthetic pigment contents,including chlorophyll-a(6%–60%),chlorophyll-b(19%–55%),and total carotenoids(26%–114%).Exogenous microalgae also contributed to the reduction of membrane damage,as proven by significantly decreased levels of malondialdehyde(10%–39%)in the leaves of the broccoli plants exposed to drought stress.The application of microalgae increased the total flavonoid and phenolic contents,and nutrition uptake.Furthermore,the activities of enzymatic antioxidants like ascorbate peroxidase,catalase,glutathione reductase,and superoxide dismutase increased in response to mediation,resulting in significant alleviation of drought-induced oxidative damage.The most effective application concentration of microalgae was determined as 5%.Overall investigations revealed that the foliar application of microalgae could be recommended as a sustainable strategy to improve the defense system of drought-stressed broccoli plants.
基金supported by the Shandong Province’s Natural Science Foundation(No.ZR2019MD033).
文摘Endophytic bacteria are promising bacterial fertilizers to improve plant growth under adverse environment.For ecological remediation of coastal wetlands,it was necessary to investigate the effect and interaction of endophytes on halophytes under saline-alkali stress.In this study,an endophytic bacterium strain HK1 isolated from halophytes was selected to infect Suaeda glauca under pH(7 and 8)and salinity gradient(150,300 and 450mmolL^(-1)).Strain HK1 was identified as Pantoea ananatis and it had ability to fix nitrogen,dissolve inorganic phosphorus and produce indole-3-aceticacid(IAA).The results showed that strain HK1 could promote the growth of S.glauca seedings when the salinity was less than 300mmolL^(-1),in view of longer shoot length and heavier fresh weight.The infected plants could produce more proline to decrease the permeability of cells,which content increased by 26.2%–61.1%compared to the non-infected group.Moreover,the oxidative stress of infected plants was relieved with the malondialdehyde(MDA)content decreased by 16.8%–32.9%,and the peroxidase(POD)activity and catalase(CAT)activity increased by 100%–500%and 6.2%–71.4%,respectively.Statistical analysis revealed that increasing proline content and enhancing CAT and POD activities were the main pathways to alleviate saline-alkali stress by strain HK1 infection,and the latter might be more important.This study illustrated that endophytic bacteria could promote the growth of halophytes by regulation of osmotic substances and strengthening antioxidant activities.This finding would be helpful for the bioremediation of coastal soil.
基金supported jointly by the earmarked fund for CARS-10-GW2the key research and development program of Hainan Province(Grant No.ZDYF2020226)+1 种基金Collaborative innovation center of Nanfan and high-efficiency tropical agriculture,Hainan University(Grant No.XTCX2022NYC21)funding of Hainan University[Grant No.KYQD(ZR)22123]。
文摘Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairments is essential for the long-term production of sweetpotatoes.Melatonin has been recognised for its capacity to assist plants in dealing with abiotic stress conditions.This research aimed to investigate how different doses of exogenous melatonin influence heat damage in sweetpotato plants.Heat stress drastically affected shoot and root fresh weight by 31.8 and 44.5%,respectively.This reduction resulted in oxidative stress characterised by increased formation of hydrogen peroxide(H_(2)O_(2))by 804.4%,superoxide ion(O_(2)^(·-))by 211.5%and malondialdehyde(MDA)by 234.2%.Heat stress also reduced chlorophyll concentration,photosystemⅡefficiency(F_v/F_m)by 15.3%and gaseous exchange.However,pre-treatment with 100μmol L^(-1)melatonin increased growth and reduced oxidative damage to sweetpotato plants under heat stress.In particular,melatonin decreased H_(2)O_(2),O_(2)^(·-)and MDA by 64.8%,42.7%and 38.2%,respectively.Melatonin also mitigated the decline in chlorophyll levels and improved stomatal traits,gaseous exchange and F_(v)/F_(m)(13%).Results suggested that the favorable outcomes of melatonin treatment can be associated with elevated antioxidant enzyme activity and an increase in non-enzymatic antioxidants and osmo-protectants.Overall,these findings indicate that exogenous melatonin can improve heat stress tolerance in sweetpotatoes.This stu dy will assist re searchers in further investigating how melatonin makes sweetpotatoes more resistant to heat stress.
基金Researchers Supporting Project No.(RSP2025R390),King Saud University,Riyadh,Saudi Arabia.
文摘Nickel(Ni)toxicity significantly impairs plant growth,photosynthesis,and metabolism by inducing oxidative stress.This study evaluates the potential of exogenous Alpha-Ketoglutarate(AKG)in mitigating Ni-induced stress in Peganum harmala L.Seedlings were exposed to 0,200,500,and 750μM NiCl2,with or without AKG supplementation.Under 750μM Ni stress,dry weight(DW)decreased by 33.7%,tissue water content(TWC)by 39.9%,and chlorophyll a and total chlorophyll levels were reduced by 17%and 15%,respectively.Ni exposure also significantly increased secondary metabolite production,with leaf anthocyanin content rising by 131%,and superoxide dismutase(SOD)and catalase(CAT)activities increasing by 228%and 53%,respectively,in roots at 500μM Ni.AKG treatment alleviated Ni toxicity by enhancing TWC by 39%and promoting root and shoot growth.Additionally,AKG treatment boosted the synthesis of phenolic compounds and flavonoids,contributing to improved tolerance against Ni stress.These findings demonstrate the potential of AKG in enhancing Ni tolerance in P.harmala,suggesting its promising role in bioremediation of metal-contaminated soils.This is the first study to report the beneficial effects of exogenous AKG in alleviating nickel toxicity in P.harmala L.,offering a new approach for improving plant resilience to heavy metal stress.
文摘Salt stress is a major threat to crop agricultural productivity.Salinity affects plants’physiological and biochemical functions by hampering metabolic functions and decreasing photosynthetic rates.Salinity causes hyperosmotic and hyperionic stress,directly impairing plant growth.In this study,eggplant seeds primed with moringa leaf extract(5%,10%,and 15%),nano-titaniumdioxide(0.02%,0.04%,and 0.06%),and ascorbic acid(0.5,1,and 2 mM)at different NaCl salt(0,75,and 150 mM)concentration were grown.The germination attributes(final germination percentage,germination index,mean germination time,and mean germination rate)and growth(root length,shoot length,fresh biomass,and dry biomass)were enhanced in the primed seedlings by the different priming agents,more prominently in ascorbic acid primed seedlings.The accumulation of hydrogen peroxide was greater in seedlings with higher salt levels.Similarly,the activity of antioxidant enzymes(superoxide dismutase,peroxidase,and catalase)was higher in primed seedlings compared to the control.At 150 mM,the antioxidant capacity was higher than 75 mM,and the seedlings’sodiumand chloride content was higher.The results demonstrate that seedling germination,growth,and activity of the antioxidant enzymes in ascorbic acid-primed seedlings increase their tolerance to salinity.Therefore,using different ascorbic acid concentrations(0.5,1,and 2 mM)as a priming agent to enhance germination and growth in saline conditions has proven effective.
基金supported by the Faculty of Medicine,Srinakharinwirot University(Research Grant 129/2560).
文摘Objective:To investigate the mechanisms by which unripe papaya extract(UCP)protects skin keratinocytes from UVB-induced inflammation and apoptosis.Methods:High-performance liquid chromatography was used to identify the phytochemical composition of UCP.The free radical scavenging capacity of UCP was assessed against O_(2)·^(-),and H2O2.HaCaT cells were pre-treated with varying concentrations of UCP and exposed to 40 mJ/cm2 UVB radiation.Cell viability,reactive oxygen species(ROS)levels,apoptotic markers,and inflammatory mediators were evaluated using standard biochemical assays and molecular techniques.Results:UCP treatment significantly improved cell viability and reduced intracellular ROS and the release of O_(2)·^(-)and H2O2.UCP also inhibited apoptosis,as evidenced by reduced cytochrome c release and suppression of Akt phosphorylation.Additionally,UCP exhibited anti-inflammatory effects by downregulating COX-2 expression,suppressing PGE2 release,and inhibiting c-Jun and NF-κB signaling pathways.Conclusions:UCP effectively protects skin keratinocytes from UVB-induced oxidative stress,inflammation,and apoptosis.These findings support its potential as a natural therapeutic agent for preventing UV-related skin damage.However,in vivo studies are warranted to confirm its efficacy.
基金supported by the Open Fund of Anhui Engineering Research Center for Ecoagriculture of Traditional Chinese Medicine(WXZR202318)High-level Talents Research Initiation Fund of West Anhui University(WGKQ2022025)+3 种基金Quality Engineering Project of West Anhui University(wxxy2024011)Quality Engineering Project of Anhui Province(2024zybj032)Development of Big Data Integration and Analysis Platform for Traditional Chinese Medicine Genomics(0045025050)Anhui Innovation and Entrepreneurship Training Program for College Students(S202510376030).
文摘Heavy metal pollution has become a pervasive environmental issue affecting numerous regions worldwide.Recently,there has been significant attention given to the application of nano-enabled technologies with the purpose of enhancing plant development and alleviating heavy metal stress.This study aimed to illustrate the potential of zinc oxide nanoparticles(ZnO-NPs)to enhance the morphological traits of D.huoshenense exposed to cadmium(Cd)stress.The chemical structure and elemental composition of the ZnO-NPs were characterised by a series of analytical methods,including X-ray diffraction,UV-Vis spectrometry,XPS,andTEM.Plant samples usedwere collected at 0,5,and 15 days in order to assess physiological and biochemical parameters under different Cd treatments.ZnONPs administered in pot experiments have been shown to enhance plant proliferation through the modulation of Cd enrichment levels.The results revealed that ZnO-NPs enhanced plant growth by increasing soluble sugars and proline levels,enhancing activities of antioxidant enzymes(SOD,POD,CAT,APX)and reducing electrolyte leakage(EL)and malondialdehyde(MDA)content.Furthermore,ZnO-NPs enhanced the net photosynthetic rate,transpiration,stomatal conductance,and chlorophyll content in leaves subjected to Cd stress at the 10-day sampling stage.Exogenous ZnO-NPs significantly elevated the expression of genes associated with flavonoid biosynthesis,potentially facilitating the accumulation of medicinal compounds to mitigate Cd stress.Taken together,these findings provide a novel perspective on the strategies employed by medicinal plants in response to Cd.
基金Project supported by the National Natural Science Foundation of China(22301012)the R&D Program of Beijing Municipal Education Commission(KM202310011005)。
文摘Cerium oxide nanoparticles(CeO_(2)NPs)have attracted great interest recently in the field of cosmetics due to their excellent biomedical properties to treat diseases caused by reactive oxygen species(ROS).However,a realizable synthesis approach for the large-scale synthesis of CeO_(2)NPs reaching the quality requirements of cosmetic grade is still in desperate demand.This work reports a robust solvothermal approach for the mass production of self-assembled CeO_(2)microsphere(SA CeO_(2))up to 1000 g at a time.Depending on the concentration of initial precursors,the re sulting particle sizes can be precisely tuned to obtain micro spherical samples of SA CeO_(2)-145 nm,SA CeO_(2)-420 nm and SA CeO_(2)-680 nm.Typically,the mesoporous SA CeO_(2)-420 nm with the largest specific surface area exhibits greatly enhanced number of oxygen vacancies(Ce^(3+)cations)proved by X-ray photoelectro n spectro scopy and electron paramagnetic resonance analysis.Moreover,Turbiscan stability test reveals the superior physical stability of SA CeO_(2)-420 nm suspension based on multiple light scattering technology,which contributes to reduced in-vitro cytotoxicity assessed via MTT viability assay.Therefore,SA CeO_(2)-420 nm exhibits excellent antioxidant performance with a high DPPH free radical scavenging ratio of more than 90% at a low concentration below 1 mg/mL.Importantly,SA CeO_(2)-420 nm can effectively inhibit the in-vitro release of reactive oxygen species in mitochondria caused by UVB irradiation in HaCaT cells,exerting good antioxidant activity at the cellular level.As a consequence,a significant increase in skin color and brightness can be observed after 28 d of application of the emulsion containing SA CeO_(2)-420 nm,demonstrating the potential whitening effect.This work provides a facile and readily scalable synthetic strategy of CeO_(2)microsphere and subsequently offers an innovative avenue for their cosmetic application.
基金Supported by National Natural Science Foundation of China(31270674)Science and Technology Planning Project of Zhaoqing City,Guangdong Province(2019N012)National Undergraduate Innovation and Entrepreneurship Training Program(202210580007).
文摘[Objectives]This study was conducted to investigate the regulatory effects of selenium(Se)on the content and balance of endogenous hormones and the function of antioxidant system during seed development in Red sandalwood(Pterocarpus santalinus).[Methods]Two basic treatments,seven single-fertilization treatments,and four combined fertilization treatments were designed.Sampling was conducted at 2,5,8,and 18 weeks after flower withering to measure the embryo abortion percentage(EAP),the contents of three endogenous hormones(IAA,GA_(3),ABA),and the activities of four antioxidant enzymes(CAT,APX,SOD,GR).[Results]Se application significantly inhibited embryo abortion in Red sandalwood,with Na_(2)SeO_(3)[Se(IV)]showing superior effects to Na_(2)SeO_(3)(Se(VI))and far exceeding the efficacy of individual applications of KCl,H_(3)BO_(3),CO(NH_(2))_(2),Ca(H_(2)PO_(4))_(2),NPK compound fertilizer,or EFOF.The combined treatment of Se with NPK compound fertilizer and EFOF[EFOF+NPK compound fertilizer+Se(IV)]was the most effective,reducing the abortion percentage by 77.8%compared with UMC at 18 weeks after flower withering.Se application significantly increased the levels of three endogenous hormones and the(IAA+GA_(3))/ABA ratio in Red sandalwood seeds(including the embryonic stage).In the optimal treatment,the(IAA+GA_(3))content was 240.7%,256.4%,353.7%,and 502.9%higher than that of UMC at 2,5,8,and 18 weeks after flower withering,respectively.Se application also concurrently enhanced antioxidant enzyme activities,with all four antioxidant enzymes in seeds of Se-treated plants showing significant increases.Notably,the selenoenzyme GR maintained considerably high activity even at 18 weeks after flower withering.The EAP was highly significantly negatively correlated with IAA content and GR activity,identifying IAA and(IAA+GA_(3))content as key hormonal indicators and GR as the core antioxidant enzyme,together constituting the central regulatory factors.The results indicate that Se suppresses embryo abortion in Red sandalwood through a dual regulatory pathway:by elevating IAA and GA_(3)levels along with the(IAA+GA_(3))/ABA ratio to optimize hormonal signaling networks,and by enhancing the activities of antioxidant enzymes such as GR to alleviate oxidative stress induced by cool-season low temperatures.[Conclusions]This study provides a theoretical basis and technical strategy for precision fertilization and stress resistance management in the cultivation of Red sandalwood.
文摘[Objective] The mitigative effect of antioxidase system of a rice mutant with low chlorophyll b on photooxidative damage was studied.[Method] A rice mutant with low chlorophyll b and its wild type were taken as experimental materials to comparatively research their peroxide (H2O2) contents, the activity and isozymes of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in chloroplast.[Result] Compared with the wild type, there were many kinds of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant, and the activity of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant was also correspondingly higher. Under intense light condition, the H2O2 content of chloroplast in mutant was less than that in the wild type. [Conclusion] The higher activity of scavenging active oxygen can relieve the photooxidative damage made by excessive light energy of intense light on photosynthetic membrane, which is an important reason for higher photosystem Ⅱ (PS II) stability of this mutant.
文摘This article aims to study the effects of exogenous 24-epibrassinolide （EBR） on the changes in ROS, activities of antioxidative enzymes and antioxidants in cucumber （Cucumis sativus L.） seedling roots under hypoxia stress. Seedlings of a hypoxiaresistant cultivar, Lühachun 4, and a hypoxia-sensitive cultivar, Zhongnong 8, were hydroponically grown for 8 d in normoxic or hypoxic nutrient solutions that were added or not added with 10^-3 mg L^-1 EBR. Under hypoxia stress, the ROS levels and the lipid peroxidation were significantly increased in the roots upon exposure to hypoxia stress, which were inhibited by EBR application. The EBR treatment significantly increased the seedlings growth and SOD, APX, GR activities, and contents of AsA and GSH under hypoxia stress. From the results obtained in this study, it can be concluded that oxidative damage on seedling roots by hypoxia stress can be considerably alleviated and the tolerance of plants was elevated.
文摘[Objective] The aim was to understand defense mechanism of pear after inoculated Botryosphaeria berengeriana f. sp. piricolan and mechanism of antioxidant enzymes of biocontrol bacteria. [Method] Pears were treated by Botryosphaeria berengeriana f. sp. piricolan and bio control bacteria, and the change of antioxidant enzymes were determined. [Result] The biocontrol bacteria had little effect on MDA;the content of MDA treated by B. berengeriana reached high peak in 48 h, was 10.22nmol/g which was 1.86 times of CK; the content of MDA treated by B. berengeriana and biocontrol bacteria reached high peak in 24 h, was 8.92 nmol/g which was1.62 times of CK. The content of SOD treated by biocontrol bacteria reached high peak in 48 h, was 126.69 U/[g（FW）·min] which was 1.54 times of CK; the contents of SOD treated by B. berengeriana as well as B. berengeriana and biocontrol bacteria reached high peak in 24 h, were 122.10 and 135.32 U/[g（FW）·min] which were 1.48 and 1.65 times of CK respectively; the contents of POD on biocontrol bacteria treatment, B. ana treatment as well as B. berengeriana and biocontrol bacteria treatment reached high peak in 24 h, were 385.34, 342.50 and 290.00 U/[g（FW）·min] which were 1.83, 1.62 and 1.38 times of CK respectively. The contents of CAT on biocontrol bacteria treatment, B. rengeriana treatment as well as B. berengeriana and biocontrol bacteria treatment reached high peak in 6 h, were 133.33,114.17 and 113.35 U/[g（FW）·min] which were 1.33, 1.14 and 1.13 times of CK respectively. The biocontrol bacteria had little difference in CK; the content of PPO of B. berengeriana treatment reached high peak in 12 h, was 81.86 U/[g（FW）·min]which was 1.76 times of CK; B. berengeriana and biocontrol bacteria treatment reached high peak in 24 h, was 70.00 U/[g（FW）·min] which was 1.50 times of CK.[Conclusion] B. berengeriana and biocontrol bacteria had more effect on MDA; both B. berengeriana and biocontrol bacteria could increase the excitation of SOD enzyme activity; both B. berengeriana and biocontrol bacteria could increase the excitation of POD enzyme activity; both B. berengeriana and biocontrol bacteria could increase the excitation of CAT enzyme activity; using biocontrol bacteria alone had not obvious effect on PPO, B. berengeriana could increase the excitation of PPO enzyme activity.
基金Supported by Science and Technology Innovation Project of Ji'nan City "Identification of Stress-resistant Malus sieversii Germplasm Resources and Screening of Stressresistance Functional Genes"(201401125)~~
文摘By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents.
基金the National Natural Science Foundation of China （30570445） Natural Science Foundation of Liaoning Province, China （20021022）+1 种基金 Tackle Key Problem of Science and Technology, Education Department of Liaoning Province, China （2004D005）and Director Foundation of ExperimentalCentre, Shenyang Normal University, China （SY200406）.
文摘This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide （H2O2） will alleviate NO2-caused injury. Twenty-eight-day-old B. campestris plants sprayed with 10 mmol L^-1 H2O2 aqueous solution （corresponding to approximate 1.0 mg H2O2 per single plant） were exposed to different concentrations of NO2 （0.25, 0.5, 1.0, and 2.0 μL L^-1, respectively） for 24 h under controlled environment. To measure the plant biomass, the plants were fumigated with the same NO2 concentrations as mentioned above for 7 h per day （8.00-15.00） for 7 days. As a control, charcoal filtered air alone was applied. Data were collected on plant biomass, total chlorophyll, photosynthetic rate, stomatal conductance, nitrate and nitrate reductase （NR）, antioxidative enzymes, ascorbate （ASA）, and malondialdehyde （MDA）, immediately after exposure. The results showed that exposure to a moderate dose of NO2 （e.g., 0.25 μL L^-1） had a favorable effect on plants, and the dry weight of the above-ground part increased, whereas the exposure to high NO2 concentrations （e.g., 0.5 μL L^-1 or higher） caused a reduction in the plant biomass and the total chlorophyll, when compared with the control. In addition, at 0.5 μL L^-1 or higher NO2 concentrations, prominent increases in the MDA level and superoxide dismutase （SOD） and NR activities were observed. Exposure to 1 μL L^-1 and higher NO2 resulted in necroses appearing on older leaves, and an increase in catalase （CAT） activity, decrease in ASA content, increased accumulation of NO3^-, and reduction in photosynthesis, when compared with the controls. No changes were detected in stomatal conductance under NO2 fumigation. The pretreatment with 10 mmol L^-1 H2O2 alleviated significantly NO2- caused biomass decrease and photosynthetic inhibition when compared with H2O2-untreated plants. Under NO2 fumigation, further induction in SOD and CAT activities occurred in H2O2 treated plants when compared with H2O2- untreated plants. The effect of NO2 on the ASA and MDA contents was also absent in H2O2-treated plants. However, the H2O2 treatment did not alter the nitrate content and NR activity in plants under NO2 fumigation. The H2O2 treatment caused a lower rate of stomatal conductance. Taken together, these data suggest that fumigation with an acute level of NO2 causes oxidative damage to B. campestris seedlings. The H2O2 pretreatment markedly protects plants against NO2 stress and this may be associated with inducible antioxidative level. NO2 fumigation contributes, at least in part, to the enhanced levels of nitrate in B. campestris leaves.
