The Mediation of Defense Responses of Ginseng Cells to an Elicitor from Cell Walls of Colletotrichum lagerarium by Plasma Membrane NAD(P)H Oxidases

NAD(P)H oxidases were detected in suspension cultured cells of ginseng (Panax ginseng C. A. Meyer). The activities of these enzymes were induced by an elicitor (Cle) extracted from cell walls of Col-letotrichum lagerarium. In addition, Cle induced an oxidative burst and enhanced the synthesis of saponin, activity of phenylalanine ammonialyase (PAL) , accumulation of chalcone synthase (CHS) and the transcription of a hydroxyproline-rich glycoprotein gene ( hrgp ) . Pre-treatments with DPI and quinacrine (two inhibitors of mammalian neutrophil plasma membrane NADPH oxidase) for 30 min prior to Cle addition blocked the NAD(P)H oxidase activity induced by Cle. These inhibitors also inhibited the release of H2C2, the synthesis of saponin, PAL activity and CHS accumulation. Our data revealed homology between plasma membrane NAD(P)H oxidases of mammalian neutrophil cells and ginseng suspension cells. They also indicated that deactivated NAD(P)H oxidases catalysed the release of H2O2 and that H2O2 was functioning as a second messenger stimulating PAL activity, saponin synthesis and hrgp transcription. Elevations of Ca2 + and protein phos-phorylation/dephosphorylation were required for this defense process. We propose that NAD(P)H oxidases mediate the processes of Cle-induced defense responses in ginseng suspensions, and postulate the existence of a signalling cascade including extracellular Cle stimulation, activation of plasma membrane NAD(P)H oxidases, release of H2O2, and the intracellular responses of metabolism and gene transcription in ginseng suspension cells.

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.

Changes in the gut microbiota mediate the differential regulatory effects of two glucose oxidases produced by Aspergillus niger and Penicillium amagasakiense on the meat quality and growth performance of broilers

Background: Glucose oxidase(GOD), an aerobic dehydrogenase, has been used as an antibiotic substitute in feed.A study was conducted to evaluate the differential effects of 2 different GODs fermented by Aspergillus niger or Penicillium amagasakiense on caecal microbiota and to further illuminate the potential roles of changes in the gut microbiota in regulating the growth performance and meat quality of broiler chickens.Results: A total of 420 one-day-old healthy Arbor Acres broilers were randomly assigned to 4 treatments: the control group,the antibiotic growth promoter(AGP) supplementation group, and the GOD-A and GOD-P(GODs produced by A. niger and P. amagasakiense, respectively) groups. As a result, supplementation with GOD produced by P. amagasakiense could significantly improve the average daily weight gain and average daily feed intake of broilers before 21 days of age by significantly increasing the enzymatic activities of jejunal amylase and those of ileal amylase, chymotrypsin, and lipase in21-day-old broilers and could increase the enzymatic activities of duodenal amylase, jejunal amylase and lipase, and ileal chymotrypsin and lipase in 42-day-old broilers. Meanwhile, compared with AGP treatment, supplementation with GOD produced by P. amagasakiense significantly decreased the L value of 21-day-old broilers and the Δp H and L* value of 42-day-old broilers, while supplementation with GOD produced by A. niger significantly increased the p H24 hvalue of 21-day-old and 42-day-old broilers by reducing plasma malondialdehyde content. By using 16 S r RNA sequencing, we found that the beneficial bacteria and microbiota in broilers were not disturbed but were improved by GOD supplementation compared with ADP treatment, including the genera Eubacterium and Christensenel a and the species uncultured_Eubacterium_sp,Clostridium_asparagiforme, and uncultured_Christensenel a_sp, which were positively related to the improved intestinal digestive enzymatic activities, growth performance, and meat quality of broilers.Conclusion: The altered gut microbiota induced by supplementation with glucose oxidase produced by P. amagasakiense mediate better regulatory effects on the meat quality and growth performance of broilers than that induced by supplementation with glucose oxidase produced by A. niger.

DNA methylation of the Monoamine Oxidases A and B genes in postmortem brains of subjects with schizophrenia

Aims: We focused on DNA methylation of the promoter regions of the Monoamine Oxidase (MAO) A and B genes from postmortem brains of subjects with schizophrenia. Methods: We determined levels of DNA methylation using genomic DNA samples purified from four brain areas: prefrontal cortex (PFC), hippocampus, occipital cortex and nucleus accumbens (NAc), by a bisulfite sequencing method from seven normal subjects and six subjects with schizophrenia. Results: Although very few methylated CpGs of the MAOA and MAOB genes were detected in male samples, various DNA methylation patterns were present in female samples, and some differences were found in such patterns between normal subjects and subjects with schizophrenia. In the PFC, the average level of methylation of both genes was significantly higher in subjects with schizophrenia than in normal subjects. The content of highly methylated alleles of the MAOA gene in the NAc was significantly associated with schizophrenia, with similar results obtained for the MAOB gene in both the NAc and PFC. Some CpG sites showed higher levels of methylation in schizophrenia than in normal subjects. Conclusions: Levels of methylation were quite high in NAc and PFC in female subjects with schizophrenia compared with those in female normal subjects.

Age-Related Surface Oxidases Shed into Body Fluids as Targets to Prevent Skin Aging and Reduce Cardiovascular Risk

Age-related Ecto-Nicotinamide Adenine Dinucleotide Oxidase Disulfide Thiol Exchangers 3 (ENOX3) or age-related NADH oxidases (arNOX) are expressed at the cell surface as five members of the TM-9 superfamily, initially membrane anchored, all functionally similar, with the N-termini exposed at the cell’s exterior. ECTO-NOXes are cell surface proteins with both time-keeping CoQH2 [NAD(P)H] oxidase and protein disulfidethiol interchange activities. They are designated as ECTO-NOX proteins because of their localization on the outer surface of the plasma membrane and to distinguish them from the phox-NOXes of host defense. A ca. 30 kDa N-terminal fragment is cleaved and accumulates in body fluids (serum, saliva, urine, perspiration). arNOXes appear around age 30 and increase steadily thereafter. Reduced quinones, i.e., reduced coenzyme Q, of the plasma membrane are natural substrates. NAD(P)H is oxidized as an artificial substrate. In one phase of the arNOX cycle electrons are transferred to oxygen to generate superoxide. Substrates for the shed forms of arNOX appear to be proteins of body fluids. Circulating lipoproteins and skin matrix proteins emerge as potentially important health-related targets. Through oxidation of collagen, elastin and other proteins of the skin matrix, arNOXes are major contributors to skin aging through tyrosine and thiol oxidation and subsequent cross linking. The main destructive action of arNOX, however, may be to directly oxidize circulating lipoproteins. arNOX in the blood is structured as an integral component of the LDL particle through site-specific binding. As such, arNOXes are implicated as major risk factors for cardiovascular disease due to specific oxidation of LDLs. The superoxide produced and its conversion to hydrogen peroxide would be one part of the potentially destructive properties by contribution to lipid oxidation. Inhibition of arNOX proteins provides a rational basis for anti-aging interventions and their elimination as a major risk factor of atherogenesis.

Type-B monoamine oxidase inhibitors in neurological diseases:clinical applications based on preclinical findings

Type-B monoamine oxidase inhibitors,encompassing selegiline,rasagiline,and safinamide,are available to treat Parkinson's disease.These drugs ameliorate motor symptoms and improve motor fluctuation in the advanced stages of the disease.There is also evidence suppo rting the benefit of type-B monoamine oxidase inhibitors on non-motor symptoms of Parkinson's disease,such as mood deflection,cognitive impairment,sleep disturbances,and fatigue.Preclinical studies indicate that type-B monoamine oxidase inhibitors hold a strong neuroprotective potential in Parkinson's disease and other neurodegenerative diseases for reducing oxidative stress and stimulating the production and release of neurotrophic factors,particularly glial cell line-derived neurotrophic factor,which suppo rt dopaminergic neurons.Besides,safinamide may interfere with neurodegenerative mechanisms,countera cting excessive glutamate overdrive in basal ganglia motor circuit and reducing death from excitotoxicity.Due to the dual mechanism of action,the new generation of type-B monoamine oxidase inhibitors,including safinamide,is gaining interest in other neurological pathologies,and many supporting preclinical studies are now available.The potential fields of application concern epilepsy,Duchenne muscular dystrophy,multiple scle rosis,and above all,ischemic brain injury.The purpose of this review is to investigate the preclinical and clinical pharmacology of selegiline,rasagiline,and safinamide in Parkinson's disease and beyond,focusing on possible future therapeutic applications.

NADPH oxidase 4(NOX4)as a biomarker and therapeutic target in neurodegenerative diseases

Diseases like Alzheimer’s and Parkinson’s diseases are defined by inflammation and the damage neurons undergo due to oxidative stress. A primary reactive oxygen species contributor in the central nervous system, NADPH oxidase 4, is viewed as a potential therapeutic touchstone and indicative marker for these ailments. This in-depth review brings to light distinct features of NADPH oxidase 4, responsible for generating superoxide and hydrogen peroxide, emphasizing its pivotal role in activating glial cells, inciting inflammation, and disturbing neuronal functions. Significantly, malfunctioning astrocytes, forming the majority in the central nervous system, play a part in advancing neurodegenerative diseases, due to their reactive oxygen species and inflammatory factor secretion. Our study reveals that aiming at NADPH oxidase 4 within astrocytes could be a viable treatment pathway to reduce oxidative damage and halt neurodegenerative processes. Adjusting NADPH oxidase 4 activity might influence the neuroinflammatory cytokine levels, including myeloperoxidase and osteopontin, offering better prospects for conditions like Alzheimer’s disease and Parkinson’s disease. This review sheds light on the role of NADPH oxidase 4 in neural degeneration, emphasizing its drug target potential, and paving the path for novel treatment approaches to combat these severe conditions.

Natural variation in the cytochrome c oxidase subunit 5B OsCOX5B regulates seed vigor by altering energy production in rice

Seed vigor is a crucial trait for the direct seeding of rice.Here we examined the genetic regulation of seed vigor traits in rice,including germination index(GI)and germination potential(GP),using a genome-wide association study approach.One major quantitative trait locus,qGI6/qGP6,was identified simultaneously for both GI and GP.The candidate gene encoding the cytochrome c oxidase subunit 5B(OsCOX5B)was validated for qGI6/qGP6.The disruption of OsCOX5B caused the vigor traits to be significantly lower in Oscox5b mutants than in the japonica Nipponbare wild type(WT).Gene co-expression analysis revealed that OsCOX5B influences seed vigor mainly by modulating the tricarboxylic acid cycle process.The glucose levels were significantly higher while the pyruvic acid and adenosine triphosphate levels were significantly lower in Oscox5b mutants than in WT during seed germination.The elite haplotype of OsCOX5B facilitates seed vigor by increasing its expression during seed germination.Thus,we propose that OsCOX5B is a potential target for the breeding of rice varieties with enhanced seed vigor for direct seeding.

Enhancing metformin-induced tumor metabolism destruction by glucose oxidase for triple-combination therapy

Despite decades of laboratory and clinical trials,breast cancer remains the main cause of cancer-related disease burden in women.Considering the metabolism destruction effect of metformin(Met)and cancer cell starvation induced by glucose oxidase(GOx),after their efficient delivery to tumor sites,GOx and Met may consume a large amount of glucose and produce sufficient hydrogen peroxide in situ.Herein,a pH-responsive epigallocatechin gallate(EGCG)-conjugated low-molecular-weight chitosan(LC-EGCG,LE)nanoparticle(Met–GOx/Fe@LE NPs)was constructed.The coordination between iron ions(Fe3+)and EGCG in this nanoplatform can enhance the efficacy of chemodynamic therapy via the Fenton reaction.Met–GOx/Fe@LE NPs allow GOx to retain its enzymatic activity while simultaneously improving its stability.Moreover,this pH-responsive nanoplatform presents controllable drug release behavior.An in vivo biodistribution study showed that the intracranial accumulation of GOx delivered by this nanoplatform was 3.6-fold higher than that of the free drug.The in vivo anticancer results indicated that this metabolism destruction/starvation/chemodynamic triple-combination therapy could induce increased apoptosis/death of tumor cells and reduce their proliferation.This triple-combination therapy approach is promising for efficient and targeted cancer treatment.

Benthodytes occidentpalauta sp.nov.,a new species of deep-sea holothuroid(Elasipodida:Psychropotidae)from the west of Kyushu-Palau Ridge in the Western Pacific Ocean

Benthodytes occidentpalauta sp.nov.was collected from the Kyushu-Palau Ridge at a depth of 5481 m in 2021.This new species is characterized by a gelatinous body wall,violet skin,six pairs of dorsal papillae,and a rough mid-ventral surface without tube feet.The dorsal deposits are rod-shaped and tripartite.Two types of papillae deposits as crosses with four arms with central bipartite apophyses.Ventral deposits are rods.Tentacle ossicles are rod-shaped with end protrusions.Gonad deposits are rodshaped,tripartite,and cross-shaped.The phylogenetic analyses based on cytochrome oxidase subunit 1(COI)and 16S individually and a concatenated dataset of COI and 16S genes of this species support that B.occidentpalauta sp.nov.belongs to Benthodytes.

Epiphytic zooplankton community profiles in a typical urban wetland as revealed by DNA metabarcoding

Zooplankton,a crucial component of urban wetland,are one of the effective bioindicators for monitoring the feeding stocks of organisms at higher trophic levels and assessing the ecological quality of ecosystems.However,information about the characteristics of epiphytic zooplankton community structure resulted from traditional methods is limited and hindered by the large amount of detritus and sludge attached to the macrophytes.We investigated the epiphytic zooplankton communities associated with macrophytes(Vallisneria,Nymphaea,and Thalia dealbata)in a subtropical wetland using as DNA markers of the 18 S rRNA gene and the mitochondrial cytochrome c oxidase subunit I(COI)gene.A total of 241 OTUs of zooplankton were obtained from COI amplicons,including 194 OTUs of Rotifera,22 of Cladocera,and 25 of Copepoda,while only 62 OTUs of zooplankton were obtained from 18 S rDNA amplicons including 34 OTUs of Rotifera and 28 of Copepoda.The zooplankton communities associated with the three macrophytes were similar,but they differed significantly from those in the open waters.However,there were no significant temporal differences among the zooplankton communities.Epiphytic zooplankton communities were dominated by littoral zooplankton such as Testudinella,Lecane,and Philodina.Microzooplankton,especially littoral species,utilize macrophytes as food sources and as refuges against predation.This further led to an increase inαandβdiversity of zooplankton communities in urban wetlands.Our result suggests that the joint use of multiple molecular markers could improve the taxonomic resolution and generate a comprehensive biodiversity profile of zooplankton.

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra compacta.Ferroptosis,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic neurons.However,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely elucidated.NADPH oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains unknown.The aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what mechanism.We found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease model.NADPH oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic neurons.Moreover,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model animals.Mechanistically,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic neurons.Furthermore,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced neuroinflammation.These findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

NOX4 promotes tumor progression through the MAPK-MEK1/2-ERK1/2 axis in colorectal cancer

BACKGROUND Metabolic reprogramming plays a key role in cancer progression and clinical outcomes;however,the patterns and primary regulators of metabolic reprogramming in colorectal cancer(CRC)are not well understood.AIM To explore the role of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4)in promoting progression of CRC.METHODS We evaluated the expression and function of dysregulated and survival-related metabolic genes using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes.Consensus clustering was used to cluster CRC based on dysregulated metabolic genes.A prediction model was constructed based on survival-related metabolic genes.Sphere formation,migration,invasion,proliferation,apoptosis and clone formation was used to evaluate the biological function of NOX4 in CRC.mRNA sequencing was utilized to explore the alterations of gene expression NOX4 over-expression tumor cells.In vivo subcutaneous and lung metastasis mouse tumor model was used to explore the effect of NOX4 on tumor growth.RESULTS We comprehensively analyzed 3341 metabolic genes in CRC and identified three clusters based on dysregulated metabolic genes.Among these genes,NOX4 was highly expressed in tumor tissues and correlated with worse survival.In vitro,NOX4 overexpression induced clone formation,migration,invasion,and stemness in CRC cells.Furthermore,RNA-sequencing analysis revealed that NOX4 overexpression activated the mitogen-activated protein kinase-MEK1/2-ERK1/2 signaling pathway.Trametinib,a MEK1/2 inhibitor,abolished the NOX4-mediated tumor progression.In vivo,NOX4 overexpression promoted subcutaneous tumor growth and lung metastasis,whereas trametinib treatment can reversed the metastasis.CONCLUSION Our study comprehensively analyzed metabolic gene expression and highlighted the importance of NOX4 in promoting CRC metastasis,suggesting that trametinib could be a potential therapeutic drugs of CRC clinical therapy targeting NOX4.

Pueraria isoflavones inhibit XOD and GLUT9 to decrease uric acid production and promote uric acid excretion, respectively

Objective: To analyze the possible mechanism of Pueraria isoflavones inhibiting XOD and GLUT9 to reduce uric acid production and promote uric acid excretion. Methods: August 2021-April 2022, a total of forty SPF male Kunming mice were divided into the healthy group (carboxymethylcellulose sodium at a dose of 250 mg/kg), the model group (HUA mice were given carboxymethylcellulose sodium at a dose of 250 mg/kg), the low group (HUA mice were given pueraria isoflavone at a dose of 125 mg/kg), HUA mice were given pueraria isoflavones at a dose of 250 mg/kg once d frequency)and the high group (HUA mice were given pueraria isoflavones at a dose of 500 mg/kg once d frequency) dosage groups, with 8 mice in each group. The contents of uric acid (SUA), urea nitrogen (BUN) and creatinine (SCr) in serum and urine of each group were compared before and after intervention (30 d). Statistical differences of xanthine oxidase (XOD) and human glucose transporter 9(GLUT9), cy- clooxygenase- 2(COX-2), tumor necrosis factor (TNF-α) and interleukin-1 (IL-1β) contents in renal tissues of each group after intervention (30 d) were compared. Results: After intervention, kidney inflammatory factors (COX-2, TNF-α and IL-1β) in the model group were compared. Blood and urine indexes (SUA, BUN, SCr);The contents of XOD and GLUT9 were higher than those of healthy group(P<0.05). Renal inflammatory cytokines (COX-2, TNF-α and IL-1β) in low, medium and high dose groups;Blood and urine indexes (SUA, BUN, SCr);The contents of XOD and GLUT9 were lower than those of model group, and there were low > medium > high dose groups, the comparison between the two groups had statistical significance(P< 0.05). After intervention, the contents of 3 indicators in blood or urine(COX-2, TNF-α and IL-1β) all decreased compared with before intervention, and the differences in intra-group comparison were statistically significant (P<0.05). Conclusion: Pueraria isoflavones can treat HUA mice by inhibiting the expression of XOD and GLUT9, and then play a role in reducing uric acid pro- duction and promoting uric acid excretion, as well as alleviating the degree of disease inflammation.

Copper-radical oxidases: A diverse group of biocatalysts with distinct properties and a broad range of biotechnological applications

Copper-radical oxidases(CROs)catalyze the two-electron oxidation of a large number of primary alcohols includ-ing carbohydrates,polyols and benzylic alcohols as well as aldehydes and𝛼-hydroxy-carbonyl compounds while reducing molecular oxygen to hydrogen peroxide.Initially,CROs like galactose oxidase and glyoxal oxidase were identified only in fungal secretomes.Since the last decade,their representatives have also been identified in some bacteria.CROs are grouped in the AA5 family of“auxiliary activities”in the database of Carbohydrate-Active enzymes.Despite low overall sequence similarity and different substrate specificities,sequence alignments and the solved crystal structures revealed a conserved architecture of the active sites in all CROs,with a mononuclear copper ion coordinated to an axial tyrosine,two histidines,and a cross-linked cysteine-tyrosyl radical cofactor.This unique post-translationally modified protein cofactor has attracted much attention in the past,which resulted in a large number of reports that shed light on key steps of the catalytic cycle and physico-chemical properties of CROs.Thanks to their broad substrate spectrum accompanied by the only need for molecular oxygen for catal-ysis,CROs since recently experience a renaissance and have been applied in various biocatalytic processes.This review provides an overview of the structural features,catalytic mechanism and substrates of CROs,presents an update on the engineering of these enzymes to improve their expression in recombinant hosts and to enhance their activity,and describes their potential fields of biotechnological application.

Synergistic effects of cellobiose dehydrogenase and manganese-dependent peroxidases during lignin degradation

The synergistic effects of cellobiose dehydro-genase (CDH) and manganese-dependent peroxidases (MnP) on the degradation of kraft pulp cellulolytic enzyme lignin (CEL) were investigated. Addition of CDH significantly increased the amount of water-soluble products reduced from CEL by MnP. CDH facilitated the reduction of the contents of methoxyl, carboxyl, phenolic hydroxyl and total hydroxyl groups of CEL by MnP. 1H-NMR analysis showed that addition of CDH also decreased further the amount of protons of CEL degraded by MnP. The results proved for the first time that CDH could promote degradation of lignin by MnP and suggest that CDH could not only promote degradation of cellulose but also is an important part of the lignin biodeg-radation system.

Co-evolved plant and blast fungus ascorbate oxidases orchestrate the redox state of host apoplast to modulate rice immunity

Apoplastic ascorbate oxidases(AOs)play a critical role in reactive oxygen species(RoS)-mediated innate host immunity by regulating the apoplast redox state.To date,little is known about how apoplastic effectors of the riceblast fungus Magnaportheoryzaemodulate the apoplast redox state of rice to subvert plant immunity.In this study,we demonstrated that M.oryzae MoAo1 is an Ao that plays a role in virulence by modulating the apoplast redox status of rice cells.We showed that MoAo1 inhibits the activity of rice OsAO3and OsAO4,which also regulate the apoplast redox status and plant immunity.In addition,we found that MoAo1,OsAO3,andOsAO4 allexhibit polymorphic variations whosevaried interactions orchestrate pathogen virulence and rice immunity.Taken together,our results reveal a critical role for extracellular redox enzymes during rice blast infection and shed light on the importance of the apoplast redox state anditsregulation inplant-pathogeninteractions.

Widely Untargeted Metabolome Profiling Provides Insight into Browning and Nutritional Quality Changes in Short-Term Stored Fresh-Cut Potato(Solanum tuberosum L.)Shreds

Potato(Solanum tuberosum L.)is susceptible to enzymatic browning after fresh processing,resulting in color change and potential alteration in the nutritional quality.In this study,a popular potato cultivar,Feiwuruita,was used to profile the metabolites involved in color and nutritional quality changes in fresh shreds stored at 0 and 4 h at 25°C(designated CK and CK4H,respectively).The shreds turned brown within 4 h of storage.In all,723 metabolites consisting 12 classes of compounds were detected in the samples,largely lipids,phenolic acids,alkaloids,amino acids and derivatives,flavonoids,organic acids,nucleotides and derivatives.Of these,163 metabolites accumulated differentially between CK and CK4H shreds.Polyphenolic compounds(phenolic acids and flavonoids)mostly increased in the shreds after 4 h storage.Conversely,the short-term storage drastically reduced lipid compounds(25 LysoPC and 19 LysoPE),while essential alkaloids and terpenoid compounds that are beneficial to human health increased in accumulation.The findings present global metabolome and nutritional composition changes in short-term stored shreds of Feiwuruita.This study provides important foundation for future studies on browning prevention/reduction and for better utilization of Feiwuruita.

Occurrences of Yttrium in Soil and Its Potential Impacts on Paddy Rice Triticum aestivum

[Objective] The effects of yttrium nitrate （YNO3） on biomass and antioxi- dant systems of paddy rice （Yttrium （Y）; Oxidative stress; Dismutases （SOD）; Per- oxidases （POD）, Catalases （CAT）, Paddy rice （Triticum aestivum）） together with the occurrences of Y in soils were investigated to assess its ecotoxicological effects on plant. [Method]Y solutions with various concentrations were sprinkled on soil sam- ples, which were well mixed and then put into culture dishes to culture paddy rice seeds for further evaluation. [Result] The results indicated that 25-100 mg/kg Y treatments significantly increased the biomass （total weight, root weight, shoot weight and leaf weight）, chlorophyll （CHL） content and protein content of paddy rice, whereas 200-800 mg/kg Y treatments had a converse effect. Similarly, biomarker for the antioxidant systems including superoxide dismutases （SOD）, peroxidases （POD） and catalases （CAT） all exhibited similar trends in both shoots and roots of paddy rice. At the same time, the malonaldehyde （MDA） content increased at from 25 to 100 mg/kg and decreased with concentrations of Y from 100 to 800 mg/kg in both shoots and roots of paddy rice. This indicated that Y could stimulate the growth of plant at low concentration, but inhibit the growth at relatively high concen- tration. [Conclusion] The levels of Y were 641＋49, 328_＋16 and 473_＋40 mg/kg in soils collected from mining area, farmland and navel orange orchard respectively. The levels of Y in the investigated area were higher than the benefit level （100 mg/kg）, which could cause low biomass as well as low activity of SOD, POD and CAT in paddy rice. Therefore, a more careful use of Y is necessary in crop management.

Agrobacterium tumefaciens-mediated transformation of embryogenic callus and CRISPR/Cas9-mediated genome editing in‘Feizixiao'litchi

Litchi(Litchi chinensis Sonn.)is a type of commercially prevalent subtropical and tropical fruit.Since litchi has a highly heterozygous genetic background and a long reproductive cycle,conventional breeding methods(such as hybridization)have limited ability to nurture new litchi cultivars.Here,an efficient and stable Agrobacterium tumefaciens-mediated genetic transformation of embryogenic callus was established in‘Feizixiao’litchi.Transgenic materials were verified using polymerase chain reaction(PCR)analysis,β-glucuronidase(GUS)assay,and green fluorescent protein(GFP)assay.To implement the technology of the Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)/associated protein 9(CRISPR/Cas9)technology in‘Feizixiao’litchi and verify the validity of these transformation systems,the litchi polyphenol oxidase gene(LcPPO,JF926153)was knocked out.Various categories of mutations,covering base insertions,deletions,and substitutions,were found in transgenic materials via sequence analysis.The transformation system achieved high feasibility and efficiency,and the system of CRISPR/Cas9 was successfully employed to edit genes in‘Feizixiao’litchi.This work provides an essential foundation for investigating the functions of genes and accelerating litchi genetic improvement.