Total Antioxidant Capability Research Articles

Ultrathin PtTeNi nanosheets as a peroxidase mimic for colorimetric detection of ascorbic acid

Utilizing the peroxidase (POD) activity of nanozymes to construct the colorimetric sensors is a popular strategy for assessing the antioxidant capacity of biological molecules, but the detection sensitivity is often compromised by their low enzymatic activity. Pt-based nanozymes, favored by their regulated nanostructures, well provide numerous binding sites for H2O2, and exhibit enhanced POD performance. Here, we utilized a simple hydrothermal method to synthesize PtTeNi nanomaterials featured with the ultrathin sheets for detecting biological antioxidant (ascorbic acid (AA) as the model). With the TMB-H2O2 system as the colorimetric substrate, PtTeNi nanomaterial exhibited superior POD-like activity with a higher Vmax (5.02 × 10−4 mM s−1) and lower Km (3.14 mM)) in contrast to natural HRP. AA significantly inhibited the colorimetric reaction of PtTeNi-TMB-H2O2 system via competitively binding OH generated by PtTeNi-mediated H2O2 catalysis and further blocking oxTMB formation. Inspired by this fact, the PtTeNi-TMB-H2O2 colorimetric sensor successfully realized highly sensitive and selective detection of AA with a good linear range from 5 μM to 500 μM and the detection limit of 2.94 μM. For analyzing the total antioxidant capability and AA contents in actual samples (commercial drinks and vitamin C tablets), the PtTeNi-based colormetric method displayed comparable results with the commercial total antioxidant capacity assay kit, with the advantages of easy operation, convenient storage and high stability. This work fully affirms the excellent enzyme-like performance of Pt-based nanomaterial and confirms the feasibility of nanozymes-based colorimetric sensing strategy in detecting antioxidant capability of biological molecules.

Exploring the Potential of the Mixture of Alginate and Aqueous Plant Extracts as Functional Drinks for Diabetics

Diabetes, which affects millions of people every year, has led to a functional food development for diabetics. This study aimed to explore the potential of functional drinks made of a mixture of alginate and aqueous plant extracts to treat diabetics. Samples studied, were 1% alginate solution (alginate drink), aqueous plant extracts, and functional drinks consisting of a mixture of alginate-plant extracts. Those functional drinks were made from okra aqueous extract, moringa leaf aqueous extract, bay leaf aqueous extract, and guava leaf aqueous extract, each of which was mixed with alginate. The samples were analyzed for qualitative phytochemical content, dietary fiber content, total phenolic content, alpha-glucosidase inhibition, and antioxidant capability. The phytochemical content of functional drinks showed differences in color intensity and types of phytochemicals. Saponins were identified in all the drinks. The high phenolic and dietary fiber content was shown by a drink of alginate - moringa leaf extract mixture. High alpha glucoside inhibitors and antioxidant activity were shown by drinks prepared from a mixture of alginate-bay leaf extract and a mixture of alginate-guava leaf extract. Overall, drinks from a mixture of alginate-bay leaf extract and a mixture of alginate-guava leaf extract had the potential to be used to treat diabetes.

Enhancing the nutritional value and antioxidant properties of foxtail millet by solid‐state fermentation with edible fungi

AbstractFoxtail millet is typically dehulled before consumption or processing. However, foxtail millet bran also contains abundant phenolic compounds and other nutrients. Edible fungi have rich extracellular enzyme systems; are environmentally friendly and safe for consumption; and have been shown to effectively degrade lignin and cellulose. This study aimed to screen edible fungi that can effectively ferment undehusked foxtail millet, improving its nutritional value and antioxidant properties through solid‐state fermentation (SSF). The results demonstrated that fermentation utilizing Pleurotus geesteranus exhibited significant improvements in both the phenolic compound content and antioxidant properties of foxtail millet, with the optimal fermentation period determined to be 30 days. The physical and functional properties of fermented undehusked foxtail millet (FFM) flour were effectively improved, increasing crude protein, vitamin C, and crude polysaccharide contents by 11.46%, 27.78%, and 54.17%, respectively. In vitro scavenging activities of FFM were 73.19%, 93.86%, and 63.75% for 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS·+), and superoxide anion radicals (O2−), respectively. The total antioxidant capability (T‐AOC) and superoxide dismutase (SOD) activity of FFM were 1.01 mM Trolox equivalents (TE)/g and 89.05 U/g, respectively. Additionally, T‐AOC, SOD, and glutathione peroxidase (GSH‐Px) activities increased, whereas malondialdehyde (MDA) levels decreased in the heart, liver, and kidneys of mice treated with FFM flour, indicating enhanced antioxidant capacity. Therefore, fermentation with edible fungi is suitable for improving the nutritional composition and antioxidant properties of foxtail millet.

Comparative study of integrated bio-responses in deep-sea and nearshore mussels upon abiotic condition changes: Insight into distinct regulation and adaptation

Deep-sea mussels, one of the dominant species in most deep-sea ecosystems, have long been used as model organisms to investigate the adaptations and symbiotic relationships of deep-sea macrofauna under laboratory conditions due to their ability to survive under atmospheric pressure. However, the impact of additional abiotic conditions beyond pressure, such as temperature and light, on their physiological characteristics remains unknown.In this study, deep-sea mussels (Gigantidas platifrons) from cold seep of the South China Sea, along with nearshore mussels (Mytilus coruscus) from the East China Sea, were reared in unfavorable abiotic conditions for up to 8 days. Integrated biochemical indexes including antioxidant defense, immune ability and energy metabolism were investigated in the gill and digestive gland, while cytotoxicity was determined in hemocytes of both types of mussels. The results revealed mild bio-responses in two types of mussels in the laboratory, represented by the effective antioxidant defense with constant total antioxidant capability level and malondialdehyde content. There were also disparate adaptations in deep-sea and nearshore mussels. In deep-sea mussels, significantly increased immune response and energy reservation were observed in gills, together with the elevated cytotoxicity in hemocytes, implying the more severe biological adaptation was required, mainly due to the symbiotic bacteria loss under laboratory conditions. On the contrary, insignificant biological responses were exhibited in nearshore mussels except for the increased energy consumption, indicating the trade-off strategy to use more energy to deal with potential stress.Overall, this comparative study highlights the basal bio-responses of deep-sea and nearshore mussels out of their native environments, providing evidence that short-term culture of both mussels under easily achievable laboratory conditions would not dramatically alter their biological status. This finding will assist in broadening the application of deep-sea mussels as model organism in future research regardless of the specialized research equipment.

MiR-92b-3p Protects against Myocardial Ischemia-Reperfusion Injury by Inhibiting MAP3K2 in a Mouse Model.

MicroRNAs are well-known RNA regulators modulating biological functions in complex signaling networks. This work aims to explore the impact of microRNA-92b-3p (miR-92b-3p) on myocardial ischemia-reperfusion (I/R) injury. The I/R model was established by left anterior descending coronary artery ligation in mice. The hemodynamic parameters were detected through a multichannel physiological recorder. Myocardial injury markers: serum cardiac troponin I, myocardial kinase isoenzyme (creatine kinase-MB), and serum inflammatory factors (tumor necrosis factor-α, interleukin [IL]-1β, and IL-6) were evaluated by enzyme-linked immunosorbent assay. Cardiac tissue oxidative stress-related factors (malondialdehyde, glutathione peroxidase, total antioxidation capability, and superoxide dismutase) were assessed by colorimetry, myocardial pathology was observed by hematoxylin-eosin staining, and cardiomyocyte apoptosis was measured by triphosphate nick end-labeling staining, as well as the expression of miR-92b-3p and mitogen-activated protein kinase kinase kinase 2 (MAP3K2) in cardiac tissues were determined by reverse transcription quantitative polymerase chain reaction or western blot assay. The targeting relationship between miR-92b-3p and MAP3K2 was verified by bioinformatics, RNA immunoprecipitation, and luciferase reporter assays. miR-92b-3p was lowly expressed and MAP3K2 was highly expressed in myocardial I/R injury mice. Upregulation of miR-92b-3p improved hemodynamic indices, decreased serum levels of myocardial injury biomarkers, inhibited serum inflammatory response, alleviated cardiac tissue oxidative stress, relieved myocardial pathology, and reduced cardiomyocyte apoptosis during the myocardial I/R injury in mice. MAP3K2 was a direct target gene of miR-92b-3p. This research suggests that miR-92b-3p protects against myocardial I/R injury by inhibiting MAP3K2, which may provide novel candidates for treatment of myocardial I/R injury.

Assessment of Sequential Yeast Inoculation for Blackcurrant Wine Fermentation

Blackcurrant is well known for its health benefits, but its wine products are understudied. In this research, studies were conducted after non-Saccharomyces and Saccharomyces yeast strain inoculation in less than 20% (w/v) fruit must for blackcurrant fermentation. Three inoculations were carried out on blackcurrant musts, as follows: (1) sequential inoculation with Torulaspora delbrueckii (strain Biodiva) followed by Saccharomyces EC1118 strain; (2) sequential inoculation with Metschnikowia pulcherimma (strain Flavia) followed by EC1118; (3) single-strain inoculation with EC1118 as the control treatment. None of these treatments did alter sugar consumption dynamics. Biodiva inoculation had impacts on both color dynamic parameter changes and final wine color profiles compared to EC1118. The final wine compositions indicate that Biodiva treatment had a significant impact on wine pH and acidity, whereas EC1118 single-strain largely influenced wine ethanol and glycerol contents. Although the total antioxidant capabilities were close among the three produced wines, the monophenol profiles indicate that Biodiva enhanced the total anthocyanin and hydroxycinnamates content but reduced the total flavanol contents in the final wine. EC1118 and Flavia wines contained more total flavanols compared to Biodiva treatment. The nonflavonoid profiles indicate that there were no significant differences among the three treatments. Our findings provide useful information for the application of yeast strains in blackcurrant wine fermentation.

Phytochemical and in vitro biological profiling of Portulaca grandiflora whole plant extracts

P. grandiflora is a small herbaceous annual herb from Portulacaceae family and found useful in mitigating the health care crisis. The study aimed to determine the phytochemicals and to examine the in vitro antifungal, antibacterial, antioxidant and anticancer potential of Portulaca grandiflora. Crude methanolic, ethanolic and n-Hexane extracts of whole plant were used for this study. Antimicrobial properties were estimated through disk diffusion assay, antioxidant activity was determined by using 2,2-diphenyl-1-picryl-hydrazyl scavenging (DPPH), total antioxidant capability and reducing power assays. From the results it was found that methanolic extract of P. grandiflora showed the highest zone of inhibition against Pseudomonas aeruginosa and Candida albicans i.e. 36 ±1mm and 18 ±1 mm respectively with MIC of 25 μg/ml. The highest amount of gallic acid equivalent phenolic and quercetin equivalent flavonoid content were found in methanolic extract of P. grandiflora i.e. 77 ± 0.68 μg GAE/mg extract and 63 ± 1.08 μg QE/mg extract. The significant DPPH scavenging activity (P< 0.05) wasrecorded for methanolic extract of P. grandiflora (87%). Considerably greater antioxidant capacity (10 ± 1.18 μg AAE/mg) and reducing power (4.06 ± 0.18 μg AAE/mg) was observed in methanolic extract. MTT cell viability assay methanolic extract of P. grandiflora showed the IC50 of 42.70 μg/ml at 72h. Whole plant extracts in different solvents exhibit strong pharmacological properties thus suggesting it as a major source of pharmaceutical industry.

Dual-mode detection for the total antioxidant capability of skincare products based on porous CuS@CdS@Au nanoshells.

The antioxidants in skincare products play a crucial role in delaying the aging process of the skin. With the growing variety of cosmetic products, it is essential to develop effective methods for measuring their total antioxidant capability (TAC). This study introduces a novel nanoenyzme, CuS@CdS@Au nanoshells (NSs), characterized by porous morphologies and composite materials, which demonstrate remarkable localized surface plasmon resonance (LSPR) effects, thereby enhancing their photocatalytic and photothermal properties. Under 808 nm laser irradiation, these nano-enzymes exhibited superior catalytic ability for TMB oxidation and temperature increases compared to CuS or CuS @Au NSs. The TMB absorption response and temperature increase showed high sensitivity to antioxidants such as ascorbic acid, glutathione, and ferulic acid, enabling the development of a dual-mode detection strategy for quantifying the TAC in skincare products without the need for complex pretreatments. Furthermore, the temperature response-based detection results proved to be more accurate than those derived from absorption response in recovery experiments. This research not only improves the reliability of antioxidant assessments but also provides a valuable tool for quality control in the skincare industry.

Wheat Bran Protein Improves Lipid Metabolism by Downregulating the Amount of HMG-CoA Reductase in the Liver of High-Fat Diet-Fed Rats

Background. The hypolipidemic effects of wheat bran have been widely documented; however, limited research has concurrently revealed the hypolipidemic and antioxidant properties of wheat bran protein (WBP). Objective. This study investigates the impact of WBP (5% daily dietary intake) on antioxidant activity, cholesterol metabolism, and serum/hepatic lipids in high-fat diet-fed rats. Methodology. In our animal experiment, we used 12 male Wistar rats that were 4 weeks old. Biochemical indicators of fecal, serum, intestinal, and liver were tested by kits or chemical techniques. The experiment on cholesterol micellar solubility was also carried out in vitro. Results. After 28 days of feeding, the results revealed that WBP significantly reduced the levels of total cholesterol (P<0.05) in serum and liver, the levels of triglycerides (P<0.05), the levels of MDA (P<0.05), and the levels of very low-density lipoprotein and low-density lipoprotein (P<0.05), and significantly increased the levels of high-density lipoprotein (P<0.05), the levels of glutathione peroxidase, and the level of total antioxidant capability. By downregulating the level of sterol regulatory element-binding protein-2 (P<0.05), WBP also reduced the content of 3-hydroxy-3-methylglutaryl-coenzyme A (P<0.05). Conclusion. In vivo, WBP demonstrated a substantial hypolipidemic and antioxidant impact (P<0.05), while in vitro, it significantly decreased the micellar solubility of cholesterol (P<0.001).

Effect of dietary Glycyrrhiza polysaccharides on growth performance, hepatic antioxidant capacity and anti-inflammatory capacity of broiler chickens

The primary aim of this study was to investigate the impact of varying levels of dietary Glycyrrhiza polysaccharides (GPS) on the health status of broiler chickens. A total of 288 1-day-old Arbor Acres broilers were randomly assigned to four groups with six replicates, consisting of 12 chickens in each replicate. The control group (CON) was provided with the basal diet, while the experimental groups were administered 300, 600, and 900 mg/kg of GPS in the basal diet for 42 days. The results demonstrated a significant enhancement in average daily gain (ADG) as a result of GPS supplementation (P < 0.05). The dietary GPS significantly elevated total antioxidation capability (T-AOC) and the activity of antioxidant enzymes (P < 0.05), while effectively reducing the levels of malondialdehyde (MDA) in the serum and liver (P < 0.05). Administration of GPS notably inhibited the toll-like receptor 4 (TLR4) signaling pathway (P < 0.05), decreased interleukin (IL)-6 and tumor necrosis factor-α (TNF-α) levels (P < 0.05), and increased IL-4 and IL-10 levels (P < 0.05). Additionally, the expression of crucial regulators involved in liver lipid metabolism, including sterol regulatory element binding protein 1 (SREBP-1), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC) were significantly reduced (P < 0.05). In contrast, the expression of peroxisome proliferator-activated receptor alpha (PPAR-α) was significantly enhanced in the GPS-supplemented groups (P < 0.05). In conclusion, the supplementation of GPS positively influenced the growth performance, the anti-inflammatory and antioxidant capacity of the liver, as well as liver lipid metabolism in broilers.

Dietary grape seed proanthocyanidin extract improved the chemical composition, antioxidant capacity, myofiber growth and flesh quality of Nile tilapia muscle

The effects of dietary grape seed proanthocyanidin extract (GSPE) supplementation (0, 100, 200, and 400 mg/kg) on the stress response, antioxidant status, myofiber growth, and meat quality of Nile tilapia were investigated in present study. Dietary GSPE lowered serum stress-related parameters (cortisol, glucose, Na+, and lactate) and improved the total antioxidant capability with enhanced superoxide dismutase and catalase activities and reduced levels of reactive oxygen species. Meanwhile, myoglobin content, pH, color, tenderness, the water-holding capacity were improved. Dietary GSPE also increased the contents of delicious amino acids, flavor amino acids, and total amino acids, C18:3n-3 (ALA), C20:5n-3 (EPA), n-3 poly-unsaturated fatty acids, decreasing off-flavor compounds such as aldehydes and alcohols. Moreover, GSPE supplementation improved myofiber growth and muscle protein deposition likely via the activation of the IGFs/PI3K/Akt/TOR/S6K1/4E-BP1 pathway, contributing to the enhanced growth performance of Nile tilapia (Oreochromis niloticus). Together, GSPE is a promising natural food additive that enhances various important meat quality parameters of fish, and the optimal dietary GSPE requirement for maximum growth and muscle protein deposition was approximately 280 mg/kg.

Dietary Chito-oligosaccharide attenuates LPS-challenged intestinal inflammation via regulating mitochondrial apoptotic and MAPK signaling pathway

To investigate the regulatory effects of Chito-oligosaccharide (COS) on the anti-oxidative, anti-inflammatory, and MAPK signaling pathways. A total of 40 28-day-old weaned piglets were randomly allotted to 4 equal groups [including the control group, lipopolysaccharide (LPS) group, COS group, and COS*LPS group]. On the morning of d 14 and 21, piglets were injected with saline or LPS. At 2 h post-injection, whole blood samples were collected on d 14 and 21, and small intestine and liver samples were collected and analyzed on d 21. The results showed that COS inhibited the LPS-induced increase of malondialdehyde (MDA) concentration and hepatic TNF-α cytokines. COS significantly increased the serum total antioxidant capability (T-AOC) value on d 14, and total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) activities in both serum and liver on d 21. Furthermore, it increased hepatic catalase (CAT) activity. COS also increased the LPS-induced decrease in serum IgG concentrations. Immunohistochemical analysis results showed that COS significantly increased the jejunal and ileal Caspase 3, and ileal CD4+ values challenged by LPS. Dietary COS decreased the LPS-induced jejunal and ileal BAX and CCL2 mRNA levels, markedly decreased ileal COX2 and SOD1 mRNA levels, while increasing ileal iNOS. Furthermore, COS significantly increased the LPS-induced jejunal and ileal p-P38 and MyD88, as well as jejunal P38, while it effectively suppressed jejunal JNK1, and jejunal and ileal JNK2, p-JNK1, and p-JNK2 protein expressions. These results demonstrated that COS could be beneficial by attenuating LPS-challenged intestinal inflammation via regulating mitochondrial apoptotic and MAPK signaling pathways.

Effects of dietary Periplaneta americana water extract on growth, chemical composition, muscle antioxidant status, and meat quality of Nile tilapia

Abstract This study investigated the effects of dietary Periplaneta americana water extract (PAWE) supplementation (0, 1, 2, and 4 g/kg) on the chemical composition, antioxidant capacity, and meat quality in Nile tilapia. The results showed that the extract improved weight gaining rated of Nile tilapia (Oreochromis niloticus). Meanwhile, dietary PAWE decreased lactate content, glycolytic potential, centrifugal water loss, and cooking loss, and enhanced muscle pH, protein content, total sulfhydryl content and meat color in Nile tilapia muscle. Dietary PAWE also improved the total antioxidant capability with enhanced superoxide dismutase, catalase, and glutathione peroxidase activities and lowered contents of reactive oxygen species, and lipid and protein oxidation products (i.e. thiobarbituric acid reactive species and protein carbonylation). Moreover, dietary PAWE enhanced the contents of flavor amino acids, total amino acids, adenosine monophosphate, and 5′-inosine monophosphate with enhanced the taste indicators (umami, richness and sweetness). In addition, PAWE supplementation improved myofiber growth and muscle protein deposition likely by activating of the IGFs/PI3K/Akt/TOR/S6K1/4E-BP1 pathway, contributing to the enhanced growth performance of Nile tilapia. The optimal dietary PAWE requirement for maximum growth and muscle protein was approximately 3 g/kg. Together, PAWE is a promising natural food additive that enhances muscle quality and nutritional value of Nile tilapia.

Identification of Efficacy-Associated Markers to Discriminate Flos Chrysanthemum and Flos Chrysanthemi Indici Based on Fingerprint-Activity Relationship Modeling: A Combined Evaluation over Chemical Consistence and Quality Consistence.

Monitoring the quality consistency of traditional Chinese medicines, or herbal medicines (HMs), is the basis of assuring the efficacy and safety of HMs during clinical applications. The purpose of this work was to characterize the difference in hydrophilic antioxidants and related bioactivities between Flos Chrysanthemum (JH) and its wild relatives (Chrysanthemum indicum L.; YJH) based on the establishment of fingerprint-efficacy relationship modeling. The concentrations of the total phenolics and flavonoids of JH samples were shown to be generally higher than those of YJH, but the concentration distribution ranges of YJH were significantly greater compared to JH samples, possibly related to environmental stress factors leading to the concentration fluctuations of phytochemicals during the growth and flowering of Chrysanthemum cultivars. Correspondingly, the total antioxidant capabilities of JH were greatly higher than those of YJH samples, as revealed by chemical assays, including DPPH and ABTS radical scavenging activities and FRAP assays. In addition, cellular-based antioxidant activities confirmed the results of chemical assays, suggesting that the differences in antioxidant activities among the different types of Chrysanthemums were obvious. The extracts from YJH and JH samples showed significant α-glucosidase inhibitory activity and lipase-inhibitory activity, implying the modulatory effects on lipid and glucose metabolisms, which were also confirmed by an untargeted cell-based metabolomics approach. The selected common peaks by similarity analysis contributed to the discrimination of YJH and JH samples, and the modeling of the fingerprint-bioactivity relationship identified neochlorogenic acid, isochlorogenic acid A, and linarin as efficacy-associated chemical markers. These results have demonstrated that integrating HPLC fingerprints and the analysis of similarity indexes coupled with antioxidant activities and enzyme-inhibitory activities provides a rapid and effective approach to monitoring the quality consistency of YJH/JH samples.

Production of Foxtail-Millet-Based Composite Antioxidant Nutritive Flour Using Coarse Grains and Fruit Flour

Antioxidants are primarily responsible for the beneficial health effects of foxtail millet. This study evaluated a foxtail-millet-based composite antioxidant nutritive flour consisting of fermented foxtail millet, coarse grains, and fruit powders. The composition of the antioxidant nutritive flour was optimized, and it was found to be rich in antioxidant nutrients, such as phenolics (2.27 g/100 g), vitamin C (0.21 g/100 g), and polysaccharides (0.35 g/100 g). The results revealed that this composite nutritive flour has enhanced in vitro and in vivo physicochemical properties and higher antioxidant activities than commercial nutritive flour. The total antioxidant capability, superoxide dismutase (SOD) capability, and superoxide radical scavenging abilities were 0.84 mM Trolox equivalents/g, 38.29 U/g, and 42.02%, respectively. The activity of the antioxidant enzyme SOD and glutathione peroxidase increased, whereas malondialdehyde levels decreased in the liver, heart, and kidney of mice treated with the nutritive flour, indicating the potential antioxidant activity of this fermented foxtail-millet-based nutritive flour.

Characterization and anti-aging effects of polysaccharide from Gomphus clavatus Gray

In this study, a highly branched polysaccharide (GPF, 112.0 kDa) was isolated and purified from Gomphus clavatus Gray fruiting bodies. GPF was primarily composed of mannose, galactose, arabinose, xylose, and glucose at a molar ratio of 3.2:1.9:1.6:1.2:1.0. GPF was a highly branched heteropolysaccharide composed of 13 glucosidic bonds, with a degree of branching (DB) of 48.85 %. GPF exhibited anti-aging activity in vivo, significantly increased antioxidant enzymes activities (SOD, CAT and GSH-Px), improved total antioxidant capability (T-AOC) and decreased MDA level in the serum and brain of d-Gal induced aging mice. Behavioral experiments showed that GPF effectively improved learning and memory deficits in d-Gal induced aging mice. Mechanistic studies indicated that GPF could activate AMPK by increasing AMPK phosphorylation and upregulating SIRT1 and PGC-1α expression. These findings suggest that GPF has significant potential as a natural candidate to slow down aging and prevent aging-related diseases.

Structural characterization of a fucoidan from Ascophyllum nodosum and comparison of its protective effect against cellular oxidative stress with its analogues

In the present study, a fucoidan fraction (ANP-3) was isolated from Ascophyllum nodosum, and the combined application of desulfation, methylation, HPGPC, HPLC-MSn, FT-IR, GC–MS, NMR, and Congo red test elucidated ANP-3 (124.5 kDa) as a triple-helical sulfated polysaccharide constituted by →2)-α-Fucp3S-(1→, →3)-α-Fucp2S4S-(1→, →3,6)-β-Galp4S-(1→, →3,6)-β-Manp4S-(1→, →3,6)-β-Galp4S-(1→，→6)-β-Manp-(1→, →3)-β-Galp-(1→, α-Fucp-(1→, and α-GlcAp-(1→ residues. To better understand the relationship between the fucoidan structure of A. nodosum and protective effects against oxidative stress, two fractions ANP-6 and ANP-7 were used as contrast. ANP-6 (63.2 kDa) exhibited no protective effect against H2O2-induced oxidative stress. However, ANP-3 and ANP-7 with the same molecular weight of 124.5 kDa could protect against oxidative stress by down-regulating reactive oxygen species (ROS) and malondialdehyde (MDA) levels and up-regulating total antioxidant capability (T-AOC), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities. Then metabolites analysis indicated that arginine biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis metabolic pathways and metabolic biomarkers such as betaine were involved in the effects of ANP-3 and ANP-7. The better protective effect of ANP-7 compared to that of ANP-3 could be attributed to its relatively higher molecular weight, sulfate substitution and →6)-β-Galp-(1→ content, and lower uronic acid content.

Nrf2 regulates the expression of NOX1 in TNF-α-induced A549 cells

Acute lung injury causes severe inflammation and oxidative stress in lung tissues. In this study, we analyzed the potential regulatory role of nuclear factor erythroid-2-related factor 2 (Nrf2) on NADPH oxidase 1 (NOX1) in tumor necrosis factor-α (TNF-α)-induced inflammation and oxidative stress in human type II alveolar epithelial cells. In this study, A549 cells were transfected with Nrf2 siRNA and overexpression vectors for 6 h before being induced by TNF-α for 24 h. TNF-α upregulated the expression of NOX1 and Nrf2 in A549 cells. Furthermore, overexpression of Nrf2 could reduce TNF-α-induced NF-κB mRNA and protein expression after transfection with the Nrf2 siRNA vector, and the levels of IL-6, IL-8, ROS, and malondialdehyde (MDA) in TNF-α-induced A549 cells increased, while the level of total antioxidation capability (T-AOC) decreased. On the other hand, the overexpression of Nrf2 decreased the levels of IL-6, IL-8, ROS, and MDA, while increasing T-AOC. The mRNA and protein levels of NOX1 were dramatically increased by TNF-α, while those changes were notably suppressed by Nrf2 overexpression. Further studies demonstrated that Nrf2 suppressed NOX1 transcription by binding to the -1199 to -1189 bp (ATTACACAGCA) region of the NOX1 promoter in TNF-α-stimulated A549 cells. Our study suggests that Nrf2 may bind to and regulate NOX1 expression to antagonize TNF-α-induced inflammatory reaction and oxidative stress in A549 cells.

The nutrient removal and tolerance mechanism of a heterotrophic nitrifying bacterium Pseudomonas putida strain NP5 under metal oxide nanoparticles stress.

The occurrence of metal oxide nanoparticles (NPs) in wastewater treatment plants (WWTPs) has raised great concerns about their adverse impacts on nitrification performance. In this study, a heterotrophic nitrifying bacterium Pseudomonas putida strain NP5 showed strong resistance against TiO2 and NiO NPs. Under 5-50 mg/L NP stress, cell viability was still normal, and the final nutrient removal rates, always higher than 80%, were slightly inhibited. Correspondingly, the PO43--P removal rates were almost the same as those observed in the control test.Although the enzyme assay demonstrated ammonia monooxygenase and hydroxylamine oxidoreductase activities markedly decreased caused by increased reactive oxygen species (ROS) level under 50 mg/L NPs stress. The total antioxidant capability of NP5 could eliminate excess ROS to maintain a balance between oxidants and antioxidants. Besides, in response to the escalating burden of NPs, strain NP5 tended to secrete more extracellular polymeric substances (EPS), which could protect cell from being damaged by binding to ions and coating. Thus, the strong NP resistance of NP5 would help to overcome the vulnerability of the nitrification process in WWTPs.

Transformation of a short-term boar semen extender into a long-term boar semen extender by using penicillamine

This study aimed to convert a short-term semen extender into a long-term semen extender by adding penicillamine (PEN). Semen samples were collected from six boars, diluted at a concentration 3 × 10&lt;sup&gt;9&lt;/sup&gt; spermatozoa/100 ml, and divided into eight groups as follows: BTS, Merck III&lt;sup&gt;®&lt;/sup&gt;, Androstar&lt;sup&gt;®&lt;/sup&gt; Plus, PEN 0.125 mM, PEN 0.25 mM, PEN 0.5 mM, PEN 1.0 mM, PEN 2.0 mM. All the diluted semen samples were stored at 18 °C and were examined for progressive motility, viability, acrosome integrity, pH and osmolarity on days 0, 1, 3, 5 and 7 after storage. The level of the total anti-oxidative capability (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) were also measured for antioxidant activities. Fertility tests on a commercial pig farm was also conducted. On days 0, 1 and 3 of storage, no statistically significant differences in all the parameters among the extenders was observed. On day 5, the semen diluted with PEN at a concentration of 0.25 mM and Androstar&lt;sup&gt;®&lt;/sup&gt; Plus could maintain progressive motility reach of 70.0% and 76.0%, respectively (P &amp;lt; 0.01). On day 7, the semen diluted with PEN at a concentration of 0.25 mM maintained progressive motility (70.0%) and acrosome integrity (85.7%) which is comparable to long-term semen extenders (Androstar&lt;sup&gt;®&lt;/sup&gt; Plus) (P &amp;lt; 0.01). For the antioxidant activities, the level of the T-AOC, SOD and MDA varied depended on the PEN concentrations . The results of the fertility test were not different among the groups. To conclude, adding PEN at 0.25 mM in the BTS extender is able to transform a short-term semen extender into a long-term extender.