CAT Enzyme Activities Research Articles

Zebularin'in Antioksidan Enzimleri ve Galleria mellonella (Lepidoptera: Pyralidae) Lipit Peroksidasyonu Üzerindeki Etkisi

Cytosine methylation is a process that adds a methyl group to a cytosine residue of DNA to convert it to 5-methylcytosine. Zebularine (ZEB) reactivates hypermethylated genes in yeast and solid tumor cells, with DNA methyltransferases that show a preferential effect on cancer cells. We investigated the effects of various doses (0.25-32 mg/ml) of ZEB, on antioxidant enzyme activity and lipid peroxidation in wax moth Galleria mellonella last instars. Injection of ZEB in last instars G. mellonella resulted in increases in SOD, MDA, and GST levels, in order of magnitude, but not in CAT enzyme activity. Two possible reasons were predicted for these results. This effect could be a result of the inhibitory effect of ZEB on DNA methylation in G. mellonella, which leaded to reducing gene transcription in insects. Or it was likely that high oxidative stress might cause a decreasing activity of enzymes.

Remote ischemic preconditioning protects against spinal cord ischemia–reperfusion injury in mice by activating NMDAR/AMPK/PGC-1α/SIRT3 signaling

BackgroundTo study the protective effects of delayed remote ischemic preconditioning (RIPC) against spinal cord ischemia–reperfusion injury (SCIRI) in mice and determine whether SIRT3 is involved in this protection and portrayed its upstream regulatory mechanisms.MethodsIn vivo, WT or SIRT3 global knockout (KO) mice were exposed to right upper and lower limbs RIPC or sham ischemia. After 24 h, the abdominal aorta was clamped for 20 min, then re-perfused for 3 days. The motor function of mice, number of Nissl bodies, apoptotic rate of neurons, and related indexes of oxidative stress in the spinal cord were measured to evaluate for neuroprotective effects. The expression and correlation of SIRT3 and NMDAR were detected by WB and immunofluorescence. In vitro, primary neurons were exacted and OGD/R was performed to simulate SCIRI in vivo. Neuronal damage was assessed by observing neuron morphology, detecting LDH release ratio, and flow cytometry to analyze the apoptosis. MnSOD and CAT enzyme activities, GSH and ROS level were also measured to assess neuronal antioxidant capacity. NMDAR-AMPK-PGC-1α signaling was detected by WB to portray upstream regulatory mechanisms of RIPC regulating SIRT3.ResultsCompared to the SCIRI mice without RIPC, mice with RIPC displayed improved motor function recovery, a reduced neuronal loss, and enhanced antioxidant capacity. To the contrary, the KO mice did not exhibit any effect of RIPC-induced neuroprotection. Similar results were observed in vitro. Further analyses with spinal cord tissues or primary neurons detected enhanced MnSOD and CAT activities, as well as increased GSH level but decreased MDA or ROS production in the RIPC + I/R mice or NMDA + OGD/R neurons. However, these changes were completely inhibited by the absence of SIRT3. Additionally, NMDAR-AMPK-PGC-1α signaling was activated to upregulate SIRT3 levels, which is essential for RIPC-mediated neuroprotection.ConclusionsRIPC enhances spinal cord ischemia tolerance in a SIRT3-dependent manner, and its induced elevated SIRT3 levels are mediated by the NMDAR-AMPK-PGC-1α signaling pathway. Combined therapy targeting SIRT3 is a promising direction for treating SCIRI.

Effects of various seed priming on morphological, physiological, and biochemical traits of rice under chilling stress.

Direct-seeded rice is exceptionally vulnerable to chilling stress, especially at the seed germination and seedling growth stages in the early season of the double cropping system. Therefore, we conducted two experiments to evaluate the role of various seed primings and their different concentrations of plant growth regulators [experiment 1-abscisic acid (ABA), gibberellin (GA3), salicylic acid (SA), brassinolide (BR), paclobutrazol, uniconazole (UN), melatonin (MT), and jasmonic acid (JA)] and osmopriming substances (chitosan, polyethylene glycol 6000 (PEG6000), and CaCl2) and experiment 2-GA, BR (two best), CaCl2 (worst), and control (CK)] on rice seedlings under low temperature condition. Results showed that the maximum germination rate of 98% was recorded in GA3 (10 mgL-1) and BR (0.3 mgL-1) among treatments. Compared to CK, root and shoot length were improved in ABA (0.5 mgL-1) and GA3 (100 mgL-1) by 64% and 68%, respectively. At the same time, root and shoot weights (fresh and dry) were enhanced in Paclobutrazol (300 mgL-1) and GA3 among treatments. Furthermore, the average root volume, average root diameter, and total root surface area were increased by 27%, 38%, and 33% in Paclobutrazol (300 mgL-1), Paclobutrazol (200 mgL-1) and JA (1 mgL-1) treatments, respectively compared to CK. In the second experiment, a respective increase of 26%, 19%, 38%, and 59% was noted in SOD, POD, CAT, and APX enzyme activities in GA treatment compared to CK. Similarly, proline, soluble sugar, soluble protein, and GA content were also improved by 42%, 25.74%, 27%, and 19%, respectively, in GA treatment compared to CK. However, a respective reduction of 21% and 18% was noted in MDA and ABA content in GA treatment compared to CK. Our finding highlighted that better germination of primed-rice seedlings was associated with fresh and dry weights of the roots and shoots and the average root volume of the seedlings. Our results suggested that GA3 (10 mg L-1) and BR (0.3 mg L-1) seed priming prevent rice seedlings from chilling-induced oxidative stress by regulating antioxidant enzyme activities and maintaining ABA, GA, MDA, soluble sugar, and protein content. However, further studies (transcriptome and proteome) are needed to explore the molecular mechanisms involved in seed priming-induced chilling tolerance under field conditions.

A Diet Containing Rutin Ameliorates Brain Intracellular Redox Homeostasis in a Mouse Model of Alzheimer’s Disease

Quercetin has been studied extensively for its anti-Alzheimer's disease (AD) and anti-aging effects. Our previous studies have found that quercetin and in its glycoside form, rutin, can modulate the proteasome function in neuroblastoma cells. We aimed to explore the effects of quercetin and rutin on intracellular redox homeostasis of the brain (reduced glutathione/oxidized glutathione, GSH/GSSG), its correlation with β-site APP cleaving enzyme 1 (BACE1) activity, and amyloid precursor protein (APP) expression in transgenic TgAPP mice (bearing human Swedish mutation APP transgene, APPswe). On the basis that BACE1 protein and APP processing are regulated by the ubiquitin-proteasome pathway and that supplementation with GSH protects neurons from proteasome inhibition, we investigated whether a diet containing quercetin or rutin (30 mg/kg/day, 4 weeks) diminishes several early signs of AD. Genotyping analyses of animals were carried out by PCR. In order to determine intracellular redox homeostasis, spectrofluorometric methods were adopted to quantify GSH and GSSG levels using o-phthalaldehyde and the GSH/GSSG ratio was ascertained. Levels of TBARS were determined as a marker of lipid peroxidation. Enzyme activities of SOD, CAT, GR, and GPx were determined in the cortex and hippocampus. ΒACE1 activity was measured by a secretase-specific substrate conjugated to two reporter molecules (EDANS and DABCYL). Gene expression of the main antioxidant enzymes: APP, BACE1, a Disintegrin and metalloproteinase domain-containing protein 10 (ADAM10), caspase-3, caspase-6, and inflammatory cytokines were determined by RT-PCR. First, overexpression of APPswe in TgAPP mice decreased GSH/GSSG ratio, increased malonaldehyde (MDA) levels, and, overall, decreased the main antioxidant enzyme activities in comparison to wild-type (WT) mice. Treatment of TgAPP mice with quercetin or rutin increased GSH/GSSG, diminished MDA levels, and favored the enzyme antioxidant capacity, particularly with rutin. Secondly, both APP expression and BACE1 activity were diminished with quercetin or rutin in TgAPP mice. Regarding ADAM10, it tended to increase in TgAPP mice with rutin treatment. As for caspase-3 expression, TgAPP displayed an increase which was the opposite with rutin. Finally, the increase in expression of the inflammatory markers IL-1β and IFN-γ in TgAPP mice was lowered by both quercetin and rutin. Collectively, these findings suggest that, of the two flavonoids, rutin may be included in a day-to-day diet as a form of adjuvant therapy in AD.

Differentiation of advanced generation mutant wheat lines: Conventional techniques versus Raman spectroscopy.

This research aimed to assess the feasibility of utilizing Raman spectroscopy in plant breeding programs. For this purpose, the evaluation of the mutant populations set up the application of 4 mM NaN3 to the somatic embryos obtained from mature wheat (Triticum aestivum L. Adana-99 cv.) embryos. Advanced wheat mutant lines, which were brought up to the seventh generation with salt stress tolerance by following in vitro and in vivo environments constructed by mutated populations, were evaluated using conventional techniques [measurement of antioxidant enzyme activities (SOD, CAT, and POX), total chlorophyll, TBARS, and proline contents; measurement of the concentration of Na+ and K+ ions; and evaluation of gene expression by qPCR (TaHKT2;1, TaHKT1;5, TaSOS1, TaNa+/H+ vacuolar antiporter, TaV-PPase, TaV-ATPase, and TaP5CS)] and Raman spectroscopy. In this research, no significant difference was found in the increase of SOD, CAT, and POX antioxidant enzyme activities between the salt-treated and untreated experimental groups of the commercial cultivar, while there was a statistically significant increase in salt-treated advanced generation mutant lines as compared to control and the salt-treated commercial cultivar. Proline showed a statistically significant increase in all experimental groups compared to the untreated commercial cultivar. The degradation in the amount of chlorophyll was lower in the salt-treated advanced generation mutant lines than in the salt-treated commercial cultivar. According to gene expression studies, there were statistical differences at various levels in terms of Na+ and/or K+ uptake from soil to plant (TaHKT2;1, TaHKT1;5, and TaSOS1), and Na+ compartmentalizes into the cell vacuole (TaNa+/H+ vacuolar antiporter, Ta vacuolar pyrophosphatase, and Ta vacuolar H+-ATPase). The expression activity of TaP5CS, which is responsible for the transcription of proline, is similar to the content of proline in the current study. As a result of Raman spectroscopy, the differences in peaks represent the protein-related bands in mutant lines having a general decreasing trend in intensity when compared to the commercial cultivar. Amide-I (1,630 and 1,668 cm-1), Histidine, Lysine, Arginine, and Leucine bands (823, 849, 1,241, 1,443, and 1,582 cm-1) showed decreasing wavenumbers. Beta-carotene peaks at 1,153 and 1,519 cm-1 showed increasing trends when the normalized Raman intensities of the mutant lines were compared.

Comparative transcriptome analysis reveals the regulatory mechanisms of two tropical water lilies in response to cold stress

BackgroundTropical water lily is an aquatic plant with high ornamental value, but it cannot overwinter naturally at high latitudes. The temperature drop has become a key factor restricting the development and promotion of the industry.ResultsThe responses of Nymphaea lotus and Nymphaea rubra to cold stress were analyzed from the perspective of physiology and transcriptomics. Under the cold stress, Nymphaea rubra had obvious leaf edge curling and chlorosis. The degree of peroxidation of its membrane was higher than that of Nymphaea lotus, and the content of photosynthetic pigments also decreased more than that of Nymphaea lotus. The soluble sugar content, SOD enzyme activity and CAT enzyme activity of Nymphaea lotus were higher than those of Nymphaea rubra. This indicated that there were significant differences in the cold sensitivity of the two varieties. GO enrichment and KEGG pathway analysis showed that many stress response genes and pathways were affected and enriched to varying degrees under the cold stress, especially plant hormone signal transduction, metabolic pathways and some transcription factor genes were from ZAT gene family or WKRY gene family. The key transcription factor ZAT12 protein in the cold stress response process has a C2H2 conserved domain, and the protein is localized in the nucleus. Under the cold stress, overexpression of the NlZAT12 gene in Arabidopsis thaliana increased the expression of some cold-responsive protein genes. The content of reactive oxygen species and MDA in transgenic Arabidopsis thaliana was lower, and the content of soluble sugar was higher, indicating that overexpression of NlZAT12 can improve the cold tolerance of Arabidopsis thaliana.ConclusionWe demonstrate that ethylene signalling and reactive oxygen species signalling play critical roles in the response of the two cultivars to cold stress. The key gene NlZAT12 for improving cold tolerance was identified. Our study provides a theoretical basis for revealing the molecular mechanism of tropical water lily in response to cold stress.

Response of Oxidative Stress and Antioxidant System in Pea Plants Exposed to Drought and Boron Nanoparticles.

Pea plants are sensitive to water shortages, making them less attractive to farmers. Hoping to reduce the adverse effects of drought on peas and considering the benefits of boron, this study aimed to investigate the impact of boron nanoparticles on the antioxidant system and oxidative stress biomarkers in drought-stressed peas. Experiments were performed in a greenhouse. Pea plants were treated with a suspension of B2O3 nanoparticles at 12.5, 25, and 50 ppm concentrations before ten days of water shortage. Drought effects were induced by maintaining 30% substrate moisture. This study investigated the properties of the nanoparticle suspension and different application methods for spraying and watering pea plants. The effects of B2O3 nanoparticles and drought were determined on pea growth indicators, oxidative stress biomarkers, and enzymatic and non-enzymatic antioxidants. Spraying with B2O3 nanoparticles at 12.5 ppm most effectively stimulated phenol accumulation; FRAP, DPPH, and ABTS antioxidant capacity; and APX, SOD, GPX, and CAT enzyme activity in pea leaves exposed to drought. In addition, B2O3 nanoparticles reduced the amount of MDA and H2O2 in pea plants grown on a substrate with insufficient moisture. The most substantial positive effect was found on peas affected by drought after spraying them with 12.5 ppm of B2O3 nanoparticles. B2O3 nanoparticles positively affected the pea height, leaf area, number of nodules, and yield.

Genome-wide analysis of Catalase gene family reveal insights into abiotic stress response mechanism in Brassica juncea and B. rapa.

Environmental stresses affect the yield and productivity of Brassica crops. Catalases are important antioxidant enzymes involved in reducing excess hydrogen peroxide produced by environmental stresses. In the present study, nine and seven CAT family members in two oilseed Brassica species (B. juncea and B. rapa) were identified with complete characterization based on gene and protein structure. Phylogenetic classification categorized CAT proteins into three classes and differentiated the monocot and dicot-specific CAT proteins. Further, the gene and protein characterizations revealed a high degree of conservation across the CAT family members. Differences were observed in the CAT-HEME binding affinity in CAT1, CAT2, and CAT3 isozymes, which could suggest their differential enzyme activities in different conditions. Furthermore, protein-protein interaction with other antioxidant proteins suggested their coordinated role in ROS scavenging mechanisms. Notably, the differential gene expression of BjuCATs and BraCATs and CAT enzyme activities suggested their crucial roles in major abiotic stresses faced by Brassica species. Promoter analysis in BjuCATs and BraCATs suggested the presence of abiotic-stress responsive cis-regulatory elements. Gene regulatory network analysis suggested miRNA and TF mediated stress response in BjuCATs and BraCATs. CAT family screening and characterization in Brassica sp. has established a basic ground for further functional validation in abiotic and heavy-metal stresses which can help in developing stress tolerant crops.

An Insight into the Impact of Serum Tellurium, Thallium, Osmium and Antimony on the Antioxidant/Redox Status of PCOS Patients: A Comprehensive Study.

Humans exploit heavy metals for various industrial and economic reasons. Although some heavy metals are essential for normal physiology, others such as Tellurium (Te), Thallium (TI), antimony (Sb), and Osmium (Os) are highly toxic and can lead to Polycystic Ovarian Syndrome (PCOS), a common female factor of infertility. The current study was undertaken to determine levels of the heavy metals TI, Te, Sb and Os in serum of PCOS females (n = 50) compared to healthy non-PCOS controls (n = 56), and to relate such levels with Total Antioxidant Capacity (TAC), activity of key antioxidant enzymes, oxidative stress marker levels and redox status. PCOS serum samples demonstrated significantly higher levels of TI, Te, Sb and Os and diminished TAC compared to control (p < 0.001). Furthermore, there was significant inhibition of SOD, CAT and several glutathione-related enzyme activities in sera of PCOS patients with concurrent elevations in superoxide anions, hydrogen and lipid peroxides, and protein carbonyls, along with disrupted glutathione homeostasis compared to those of controls (p < 0.001 for all parameters). Additionally, a significant negative correlation was found between the elevated levels of heavy metals and TAC, indicative of the role of metal-induced oxidative stress as a prominent phenomenon associated with the pathophysiology of the underlying PCOS. Data obtained in the study suggest toxic metals as risk factors causing PCOS, and thus protective measures should be considered to minimize exposure to prevent such reproductive anomalies.

Antioxidant effect of yeast on lipid oxidation in salami sausage.

Salami is a kind of fermented meat product with rich nutrition and unique flavor. Because it is rich in fat, it is easy to oxidize to produce bad flavor. Compared with the way of adding artificial or natural antioxidants to reduce the degree of sausage oxidation, the antioxidant characteristics of developing the starter itself deserve more attention. In this study, firstly the antioxidant activities of 5 strains of yeast were measured in vitro, and then the mixture of yeast and Lactobacillus rhamnosus YL-1 was applied to fermented sausage model. The effect of the starter in the sausage model was investigated through physicochemical parameters, degree of fat oxidation, free fatty acid content, and though volatile flavor compound analysis, sensory evaluation and various indexes after storage were observed. Metagenomics was used to explore metabolic pathways, functional genes and key enzymes related to lipid oxidizing substances in sausage in yeast. The results showed that Wickerhamomyces anomalus Y12-3 and Y12-4 had strong tolerance to H2O2, and had higher SOD and CAT enzyme activities. The addition of yeast effectively reduced the material value of peroxidation value and active thiobarbiturate in salami. In flavor analysis, the content of flavor compounds associated with lipid oxidation, such as hexanal, heptanal, nonanal and (E)-2-decenal were significantly lower with the use of Debaryomyces hansenii Y4-1 and Y12-3. Meanwhile, the possible pathways of yeast metabolism of flavor substances related to lipid oxidation (mainly aldehydes) were discussed with the help of metagenomic techniques. According to the results of metagenomics, fatty acid degradation (ko00071) metabolic pathway was related to the degradation of aldehydes through aldehyde dehydrogenase, which was the potential key enzyme.

A novel peptide derived from Haematococcus pluvialis residue exhibits anti-aging activity in Caenorhabditis elegans via the insulin/IGF-1 signaling pathway.

To explore the value of Haematococcus pluvialis (H. pluvialis) residue remaining after astaxanthin extraction and being discarded uneconomically, in our previous study, we discovered a novel peptide (HPp) as a potential bioactive component. However, the possible anti-aging activity in vivo was not illuminated. In this study, the capacity of extending the lifespan and the mechanism based on Caenorhabditis elegans (C. elegans) were determined. The results showed that 100 μM HPp not only enhanced the lifespan of C. elegans in normal environments by 20.96% but also strengthened the lifespan in oxidative and thermal conditions effectively. Moreover, HPp succeeded in lessening the decline in physiological functions of aging worms. In terms of antioxidant efficacy, SOD and CAT enzyme activity were promoted, but the level of MDA was diminished significantly after HPp treatment. Subsequent analysis directly reflected the relationship between higher stress resistance and up-regulation of skn-1 and hsp-16.2, and between greater antioxidant ability and up-regulation of sod-3 and ctl-2. Further studies illustrated that HPp up-graded the mRNA transcription of the genes associated with the insulin/insulin-like growth factor signaling (IIS) pathway and some co-factors, including daf-16, daf-2, ins-18, and sir-2.1. Particularly, the activation of the IIS pathway required the regulation of subcellular localization of DAF-16/FOXO. Taken together, HPp could promote longevity with improved stress resistance and antioxidant properties in vivo through the IIS pathway. These data suggested that HPp might serve as a good source of anti-aging actives, and in particular, laid a foundation for the high value-added application of marine microalgae.

Mechanistic role of epigallocatechin-3-gallate in regulation of the antioxidant markers in ethanol induced liver damage in mice

ABSTRACT Background: Failure of endogenous antioxidant system to eliminate high levels of ROS results to oxidative stress, consequently leading to liver damage. Excessive alcohol consumption leads to liver damage due to ROS generation, thus regarded as the leading causes of death worldwide, suggesting great need for use of exogenous antioxidants like epigallocatechin-3-gallate (EGCG), to avert liver damage. However, underlying EGCG mechanisms remains elusive.Aim of the work: This study focused on mechanistic role of EGCG in regulation of antioxidant marker activities during ethanol induced liver damage.Materials and Methods: 20 male Swiss Albino mice were divided into four groups and treated with different dosage. ALT, AST and total proteins were determined as indicators of liver damage. MDA and protein carbonyls were measured as oxidative stress markers. Activities of SOD and CAT were determined. SOD-2 and CAT differential gene expression were also determined. Liver histology analysis by H&E staining. All the experiments were run in duplicates. ANOVA was used to analyzes data using Tukey’s multiple comparison tests and results considered statistically significant if p ≤ 0.05 at 95% confidence level. Results: Findings revealed that chronic consumption of ethanol leads to liver damage through increased levels of serum ALT and AST, MDA, protein carbonyls and remarkable diffuse lipid droplets and decreased enzyme activity of SOD and CAT. EGCG increased activity of SOD and CAT and SOD-2 expression and did not affect CAT expression. Conclusion: In summary, ethanol induces liver damage, and administration of EGCG increases antioxidant system expression, suggesting its role in regulating their activities, defensive of oxidative stress through various pathways.

Determination of the Effect of Salt Stress on Germination, Biochemical and Antioxidant Defense Systems in Linas Safflower Seeds

In this study, the germination and early seedling growth, biochemical and antioxidant enzyme activities (CAT, SOD, POD, and APX) of one-year, broad-leaved Linas safflower belonging to the Compositeae family were investigated at different salt concentrations (0, 50, 100, 150 and 200 mM). With increasing salt concentration, a 68.83% decrease in seedling length, 71% in stem length, 34% in germination rate, and 77% in fresh plant weight were determined. In addition, total phenolic content (267%), total flavonoid content (904%), CAT (462%), SOD (56%), POD (100%), and APX (381%) antioxidant enzyme activities were increased in parallel with the salt concentration. In addition, it was determined that as the salt stress increased, the water-soluble protein content decreased by 48%. In the study, it was determined that the seeds were relatively resistant to 100, 150, and 200 mM NaCl salt concentrations, and germination continued. As a result, it has been understood once again that our country has been feeling a negative impact lately, and the determination of alternative plants for growing oily plants has gained more importance in these days. Safflower, which is one of these plants, is a strategically important species both in terms of its oil content and being a source of biodiesel. This study carried out in this context will be a resource for our farmers regarding future studies on safflower seeds and which salt concentrations can be used for cultivation.

Biological Control of Verticillium Wilt and Growth Promotion in Tomato by Rhizospheric Soil-Derived Bacillus amyloliquefaciens Oj-2.16

Verticillium wilt disease caused by Verticillium dahliae seriously affects tomato quality and yield. In this work, strain Oj-2.16 was isolated from rhizosphere soil of the medicinal plant Ophiopogon japonicas and identified as Bacillus amyloliquefaciens on the basis of morphological, physiological, and biochemical characteristics and 16S rDNA sequencing. Strain Oj-2.16 exhibited a high inhibition rate against V. dahliae, and the hyphae inhibited by Oj-2.16 were found to be destroyed on scanning electron microscopy. Lipopeptide and dipeptide genes were detected in the Oj-2.16 genome by PCR amplification involved in surfactin, iturin, fengycin, and bacilysin biosynthesis. In pot experiments, the biocontrol efficacy of strain Oj-2.16 against Verticillium wilt in tomato was 89.26%, which was slightly higher than the efficacy of the chemical fungicide carbendazim. Strain Oj-2.16 can produce indole acetic acid, siderophores, assimilate various carbon sources, and significantly promoted the growth of tomato seedlings by increasing plant height, root length, stem width, fresh weight, and dry weight by 44.44%, 122.22%, 80.19%, 57.65%, 64.00%, respectively. Furthermore, defense-related antioxidant CAT, SOD, POD, and PAL enzyme activities significantly increased and MDA contents significantly decreased in tomato seedlings treated with strain Oj-2.16 upon inoculation of V. dahliae compared with the pathogen-inoculated control. In summary, we concluded that B. amyloliquefaciens Oj-2.16 could be used as a promising candidate for the biocontrol of Verticillium wilt and as plant growth stimulator of tomato.

Impact of Titanium Dioxide-Graphene Oxide (TiO2-GO) Composite Nanoparticle on the Juveniles of the Giant River Prawn, Macrobrachium rosenbergii: Physio-Biochemistry and Transcriptional Response

Nanomaterials are used in many fields, resulting in inevitably releasing into the aquatic environment. The presence of nanomaterials, including TiO2-GO in the aquatic environment, can be toxic to aquatic organisms. However, few studies have focused on the effects of TiO2-GO composite nanoparticle on crustaceans. In the present study, the giant river prawn Macrobrachium rosenbergii juveniles were exposed to two concentrations of TiO2-GO composite nanoparticle (0.1 and 0.5mg/L). The effects of TiO2-GO composite exposure on activities of digestive and antioxidant-related enzymes and expressions of growth and immune-related genes at the transcriptome were studied. The results showed that the survival rate and growth performance were not negatively affected by TiO2-GO composite at the two exposure levels. Nevertheless, exposure to TiO2-GO composite causes an effect on the activities of digestive and antioxidant enzymes in the juvenile prawns. The enzyme activities of CAT, SOD, GSH-Px, AMS, TPS, and LPS in the 0.1mg/L TiO2-GO composite experimental group were markedly reduced than those in the control group. Additionally, the expression level of genes involved in growth and immunity was significantly affected by TiO2-GO composite. After exposure to the 0.1mg/L TiO2-GO composite, the mRNA expression level of MSTN was significantly increased, but the level of EcR, Raptor, and CaBP was significantly decreased. However, the mRNA levels of the CTL, TLR, JAK, and STAT were significantly increased after exposure to the 0.5mg/L concentration of TiO2-GO composite. Furthermore, to understand the molecular mechanism of M. rosenbergii under TiO2-GO composite exposure, RNA-Seq was employed to analyze the changes of the muscle and hepatopancreas transcriptome. Compared with the control group, we identified 5166 and 4784 differentially expressed genes (DEGs) in the muscle and hepatopancreas, respectively (p < 0.05). Based on gene ontology and KEGG analysis, significant differences were observed in the DEGs involved in activity and binding, metabolism, immune response, and environmental information processing. These results showed that exposure to TiO2-GO composite nanoparticle led to the changes of enzyme activity and gene expression, suggesting that TiO2-GO composite existing in aquatic environments would disrupt the physiology of M. rosenbergii. This study will serve as a foundation for subsequent research into the evaluation of nanomaterial toxicity on crustacean species.

POD, CAT and SOD enzyme activity of corn kernels as affected by low plasma pretreatment

ABSTRACT In this study, low-temperature plasma was used as an efficient pretreatment method of corn kernels (XY335), which developed and optimized a process of enzyme activity. The effects of plasma pretreatment power (300, 400, 500 W), plasma pretreatment time (30, 40, 50 s) and air flow rate (100, 150, 200 mL min−1) on enzyme activity during this process were investigated. Regression equations were established through a three-factor and three-level Box-Behnken design and used to evaluate the optimal conditions for the process. The optimal pretreatment conditions of POD enzyme activity were plasma pretreatment power of 500 W, plasma pretreatment time of 30 s and air flow rate of 150 mL min−1. The optimal pretreatment conditions of CAT enzyme activity were plasma pretreatment power of 350 W, plasma pretreatment time of 30 s and air flow rate of 150 mL min−1. The optimal pretreatment conditions of SOD enzyme activity were plasma pretreatment power of 400 W, plasma pretreatment time of 30 s and air flow rate of 200 mL min−1. Results showed that low-temperature plasma can be used effectively to increase the enzyme activity of corn kernels.

Preparation of antioxidant peptides from Moringa oleifera leaves and their protection against oxidative damage in HepG2 cells.

Moringa oleifera leaves are a kind of new food raw materials, rich in functional factors, M. oleifera leaves aqueous extract have antioxidant activity and M. oleifera leave protein is an important active ingredient in the aqueous extract. Numerous studies have shown that peptides have strong antioxidant activity. To reveal the antioxidant effects of M. oleifera (MO) leaves peptides, MO leave antioxidant peptides were isolated and prepared to clarify their antioxidant activity. MLPH1 (<1 kDa), MLPH3 (1~3 kDa), MLPH5 (3~5 kDa), and MLPH10 (5~10 kDa) fractions were obtained by the membrane ultrafiltration classification of MO leaves proteolytic hydrolysate (MLPH). MLPH1 was further separated by centrifugal filters, and the fraction separated by <1 kDa (MLPH1-1) was identified and analyzed by LC-MS/MS. The purpose of this study was to investigate the effect of MO leaves antioxidant peptide pretreatment on H2O2-treated HepG2 cells and to refine the antioxidant activity. The results showed that MLPH1 had the strongest antioxidant activity, and three MO leaves antioxidant peptides (LALPVYN, LHIAALVFQ, and FHEEDDAKLF) were obtained. The peptide with the sequence LALPVYN and a molecular weight of 788.44 Da had the strongest antioxidant activity. After 24 h of LALPVYN pretreatment, the cell viability and the CAT, GSH-Px, and SOD enzyme activity were significantly increased, and the MDA, ROS, and apoptosis rates were significantly decreased. These results provide a theoretical basis for further research on the antioxidant mechanism of MO leaves peptides.

Phytoaccumulation of zinc from contaminated soil using ornamental plants species Helianthus annuus L. and Tagetes erecta L.

Intensive research on hyperaccumulator plant species provides an alternative method to cleanup heavy metal contaminated sites using these plants. Helianthus annuus and Tagetes erecta are suitable hyperaccumulator plant species for removing zinc (Zn) from contaminated soil because of their high phytoremediation effectiveness. The present study focused on to evaluate comparative efficacy of Zn accumulation using H. annuus and T. erecta. Plantlets were exposed to different Zn concentrations (10, 50, 100, 300, and 500 mg kg−1) for 20, 40, and 60 days while changes in morphological, biochemical, and enzyme activity markers were evaluated. The concentration of Zn in various plant parts was determined using an atomic absorption spectrophotometer (AAS). After 60 days H. annuus showed greatest accumulation of Zn in the root and shoot (216.7 and 109.5 mg kg−1), whereas the Zn accumulation T. erecta (209.5 and 97.84 mg kg−1) was found comparatively less in the root and shoot. The result showed increased polyphenol and proline concentrations with increasing Zn concentrations which were maximal in H. annuus 6.642 mg g−1 and 25.474 µmol g−1, respectively. At 60 days, APX (4.145 mM mg−1), CAT (2.558 mM mg−1), and GR (52.23 mM mg−1) antioxidant enzymatic activities were observed with higher concentrations. Analysis of ultrastructure confirmed Zn transport and localization in root and shoot tissues examined through FESEM-EDX, Fluorescence microscopy, and optical microscopy. The present research findings concluded with the high amount of removal of Zn from contaminated soil using H. annuus and T. erecta for ecofriendly approach to soil cleanup followed by sustainable agriculture.

Enhanced protection of tomato against Fusarium wilt through biopriming with Trichoderma harzianum

ObjectiveMicrobial priming represents an adaptive strategy to enhance the plant defense against subsequent challenges incited by pathogenic microbes. The aim of the study was to investigate the effect of priming with Trichoderma harzianum (Th) on the induced resistance potential of tomato after challenged with Fusarium oxysporum f. sp. lycopersici (Fol) pathogen. MethodsThis work demonstrated antioxidative and defense related enzyme activities and qRT-PCR to study the resistance mechanisms of tomato plants bioprimed with T. harzianum against Fol pathogen. ResultMicrobial biopriming with T. harzianum resulted into enhanced expression of tomato defense-related genes and was accompanied by increased antioxidative enzymic activities. The study reported that the T. harzianum primed plants showed 2.71-fold higher SOD than control and 1.34-fold (Fol + Th) higher SOD activity compared to Fol challenged plants. In contrast, Fol + Th treated showed 5.87-fold and 1.34-fold higher CAT enzyme activity as compared to control and pathogen exposed plants. T. harzianum bioprimed plants noted 1.47- and 11.47-fold enhanced PPO activity as compared to Fol challenged and controls, respectively. PAL and PO activities were also found higher in T. harzianum primed plants. The qRT-PCR revealed that expression of defense related gene showed higher up-regulation in T. harzianum primed plants as compared to pathogen challenged plants. As compared to control, Fol + Th treated plants also showed higher up-regulation of all the studied genes. ConclusionThe study concluded T. harzianum priming aggravates the plant defense system against the Fol challenged condition and accompanied by higher expression of defense related genes and increased antioxidative activities against subsequent Fol attack.

Silencing of SlMYB50 affects tolerance to drought and salt stress in tomato

High salinity and drought stresses often cause plants to produce ROS, including hydrogen peroxide (H2O2) and superoxide (O2−), which interfere with plant growth and affect crop yield. The transcription factors of the MYB family are involved in responses to biotic and abiotic stresses. Here, we isolated the R2R3-MYB transcription factor gene SlMYB50 and found that silencing of SlMYB50 increased resistance to PEG 6000, mannitol and salt. In addition, the resistance of transgenic tomatoes increased under high salt and drought stress. After stress treatment, the relative water content, chlorophyll content (critical for carbon fixation) and root vitality of the SlMYB50-RNAi lines were higher than those of the wild-type (WT). The opposite was true the water loss rate, relative conductivity, and MDA (as a sign of cell wall disruption). Under drought stress conditions, SlMYB50-silenced lines exhibited less H2O2 and less O2− accumulation, as well as higher CAT enzyme activity, than were exhibited by the WT. Notably, after stress treatment, the expression levels of chlorophyll-synthesis-related, flavonoid-synthesis-related, carotenoid-related, antioxidant-enzyme-related and ABA-biosynthesis-related genes were all upregulated in SlMYB50-silenced lines compared to those of WT. A dual-luciferase reporter system was used to verify that SlMYB50 could bind to the CHS1 promoter. In summary, this study identified essential roles for SlMYB50 in regulating drought and salt tolerance.