Search results for “peroxidase

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14 articles
Enzymes Open Access

Disruption of Hydrogen Bonding Network Decreases Catalytic Diversity of Chloroperoxidase via Abolishing Both Chlorination and Dismutation Activities

Nov 2024 DOI 10.14302/issn.2690-4829.jen-24-5291

The perpendicular orientation of the proximal alpha helix to the heme plane in chloroperoxidase (CPO) maximizes the influence of its intrinsic helix dipole that has been shown to reduce the “push-effect”, thereby increasing the heme redox potential and fine-tuning the catalytic capabilities of CPO. We investigated the effects of a disruption of the hydrogen bonding network between R26-N37 and A27-N33, formed by the proximal alpha helix, on the CPO structural stability and catalytic profile using site-directed mutagenesis and spectroscopy. The mutant CPO (R26A, N33A, and R26A/N33A) exhibited significant tertiary structural changes and distinct heme coordination, likely, due to destabilization of the proximal helix as a result of the disruption of the proximal hydrogen bonding network. In line with these observations, biochemical characterizations showed that all mutants displayed dramatically different activity profiles relative to that of the WT CPO. Mutant epoxidation and peroxidation activities were markedly enhanced, especially in the R26A/N33A CPO mutant. Moreover, all mutant CPO enzymes exhibited broader pH profiles in both epoxidation and peroxidation activities, including a shift in the optimal peroxidation activity towards pH 3.5 as opposed to pH 2.75. Conversely, the dismutation activity (pH 3.0-5.5) was almost completely lost while chlorination activity (pH 2.75-5.0) was virtually non-existent in all CPO mutants. Our results demonstrate the important role the R26-N37 and A27-N33 hydrogen bond pairs play in the heme coordination and tertiary structure of CPO defining its catalytic capabilities, and also suggest the importance of the proximal helix stability and orientation.

Peroxidase from Coleus Forskohlii: Purification and Biochemical Characterization

Jan 2020 DOI 10.14302/issn.2379-7835.ijn-19-3139

In this study, a peroxidase from new source was purified using ion exchange and gel filtration techniques. The recovery for peroxidase activity was 19% with 11-fold purification and specific activity of 749 unit/mg protein. Purified peroxidase demonstrated a molecular mass of 39 kDa using gel filtration and was confirmed as a single band on SDS-PAGE. The purified peroxidase revealed a broad optimum pH activity at 6.0-6.5 and 50°C temperature. The kinetic parameters for purified peroxidase toward H2O2 and guaiacol as substrates were found to be Km = 3.355, 5.395 mM, Kcat = 99.52, 79.56 s-1 and Vmax =1.531, 1.242 µmole ml-1 min-1, respectively. The catalytic efficiency (kcat/Km) of the purified peroxidase was 14.75 and 29.66 s−1 mM−1 for guaiacol and H2O2, respectively. Peroxidase activity was observed to be enhanced by Cu2+, Co2+, Ni2+ and inhibited in the presence of Sn2+, Al3+, Hg2+, NaN3, EDTA and urea. Characterization showed that peroxidase purified from C. forskohlii has the ability to be used for food industrial applications.

Antioxidant Activity Open Access

Evaluation of Antioxidative Potential of the Biofield Energy Treated Proprietary Test Formulation on L-NAME and High Fat Diet-Induced Cardiovascular Disorders in Sprague Dawley Rats

Jul 2021 DOI 10.14302/issn.2471-2140.jaa-21-3864

The aim of this experiment was to assess the antioxidative potential of the Biofield Energy Treated/Blessed Proprietary Test Formulation and Biofield Energy Treatment/Blessing per se to the animals on NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) and high fat diet (HFD)-induced cardiovascular disorders in Sprague Dawley rats using various functional biomarkers. A test formulation was formulated including minerals (magnesium, zinc, copper, calcium, selenium, and iron), vitamins (ascorbic acid, pyridoxine HCl, vitamin B9, vitamin B12, and vitamin D3), cannabidiol (CBD) isolate, Panax ginseng extract, and β-carotene. The test formulation’s constituents were divided into two parts; one part was denoted as the untreated, while the other part and three group of animals received Biofield Energy Healing/Blessing Treatment remotely for about 3 minutes by a renowned spiritual leader, Mr. Mahendra Kumar Trivedi. The expression of superoxide dismutase (SOD) was elevated significantly by 198.46%, 208.73%, 191.73%, 211.75%, and 198.82% in the G5 (L-NAME + HFD + the Biofield Energy Treated test formulation), G6 (L-NAME + HFD + Biofield Energy Treatment per se to animals from day -15), G7 (L-NAME + HFD + the Biofield Energy Treated test formulation from day -15), G8 (L-NAME + HFD + Biofield Energy Treatment per se plus the Biofield Energy Treated test formulation from day -15), and G9 (L-NAME + HFD + Biofield Energy Treatment per se animals plus the untreated test formulation) groups, respectively than disease control group (G2). Moreover, the level of glutathione peroxidase (GPx) was significantly increased by 61.94%, 118.49%, 82.96%, 141.89%, and 262.02% in the G5, G6, G7, G8, and G9 groups, respectively as compared to the G2 group. Lipid peroxidase (LPO) was decreased by 14.21%, 30.98%, 38.66%, and 32.67% in the G6, G7, G8, and G9 groups, respectively than G2 group. Additionally, the level of myeloperoxidase (MPO) was decreased by 28.46%, 10.87%, 12.41%, and 13.35% in the G6, G7, G8, and G9 groups, respectively than G2. Further, the level of oxidized low density lipoprotein (LDL) was reduced by 65.38%, 65.11%, 71.53%, 79.26%, and 66.57% in the G5, G6, G7, G8, and G9 groups, respectively than G2. Besides, in heart tissues, the level of catalase (CAT) was significantly increased by 68.20%, 63.69%, 126.03%, 124.54%, and 112.23% in G5, G6, G7, G8, and G9 groups, respectively than G2 group. Moreover, in kidney tissues, the level of CAT was significantly increased by 22.48%, 23.43%, and 10.95% in the G6, G7, and G9 groups, respectively than G2. Overall, the data suggested a significant antioxidant activity by increasing the levels of SOD, CAT, GPx, and reducing the levels of LPO, MPO, and oxidized-LDL in various tissue fluids and that might be beneficial for cardiovascular disorders. Therefore, the study outcomes showed the significant slowdown the oxidative stress-related cardiovascular disease progression and its complications in the preventive treatment groups viz. G6, G7, G8, and G9.

Antioxidant Activity Open Access

Evaluation of Antioxidative Potential of the Biofield Energy Treated Proprietary Test Formulation on L-NAME and High Fat Diet-Induced Cardiovascular Disorders in Sprague Dawley Rats

Jul 2021 DOI 10.14302/issn.2471-2140.jaa-21-3846

The aim of this experiment was to assess the antioxidative potential of the Biofield Energy Treated/Blessed Proprietary Test Formulation and Biofield Energy Treatment/Blessing per se to the animals on NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) and high fat diet (HFD)-induced cardiovascular disorders in Sprague Dawley rats using various functional biomarkers. A test formulation was formulated including minerals (magnesium, zinc, copper, calcium, selenium, and iron), vitamins (ascorbic acid, pyridoxine HCl, vitamin B9, vitamin B12, and vitamin D3), cannabidiol (CBD) isolate, Panax ginseng extract, and β-carotene. The test formulation’s constituents were divided into two parts; one part was denoted as the untreated, while the other part and three group of animals received Biofield Energy Healing/Blessing Treatment remotely for about 3 minutes by a renowned spiritual leader, Mr. Mahendra Kumar Trivedi. The expression of superoxide dismutase (SOD) was elevated significantly by 198.46%, 208.73%, 191.73%, 211.75%, and 198.82% in the G5 (L-NAME + HFD + the Biofield Energy Treated test formulation), G6 (L-NAME + HFD + Biofield Energy Treatment per se to animals from day -15), G7 (L-NAME + HFD + the Biofield Energy Treated test formulation from day -15), G8 (L-NAME + HFD + Biofield Energy Treatment per se plus the Biofield Energy Treated test formulation from day -15), and G9 (L-NAME + HFD + Biofield Energy Treatment per se animals plus the untreated test formulation) groups, respectively than disease control group (G2). Moreover, the level of glutathione peroxidase (GPx) was significantly increased by 61.94%, 118.49%, 82.96%, 141.89%, and 262.02% in the G5, G6, G7, G8, and G9 groups, respectively as compared to the G2 group. Lipid peroxidase (LPO) was decreased by 14.21%, 30.98%, 38.66%, and 32.67% in the G6, G7, G8, and G9 groups, respectively than G2 group. Additionally, the level of myeloperoxidase (MPO) was decreased by 28.46%, 10.87%, 12.41%, and 13.35% in the G6, G7, G8, and G9 groups, respectively than G2. Further, the level of oxidized low density lipoprotein (LDL) was reduced by 65.38%, 65.11%, 71.53%, 79.26%, and 66.57% in the G5, G6, G7, G8, and G9 groups, respectively than G2. Besides, in heart tissues, the level of catalase (CAT) was significantly increased by 68.20%, 63.69%, 126.03%, 124.54%, and 112.23% in G5, G6, G7, G8, and G9 groups, respectively than G2 group. Moreover, in kidney tissues, the level of CAT was significantly increased by 22.48%, 23.43%, and 10.95% in the G6, G7, and G9 groups, respectively than G2. Overall, the data suggested a significant antioxidant activity by increasing the levels of SOD, CAT, GPx, and reducing the levels of LPO, MPO, and oxidized-LDL in various tissue fluids and that might be beneficial for cardiovascular disorders. Therefore, the study outcomes showed the significant slowdown the oxidative stress-related cardiovascular disease progression and its complications in the preventive treatment groups viz. G6, G7, G8, and G9.

Antioxidant Activity Open Access

Antioxidant Activity of Biofield Treated Proprietary Test Formulation Supplemented with Vitamins and Minerals in Vitamin D3 Deficiency Diet (VDD) Induced Sprague Dawley Rats

Mar 2021 DOI 10.14302/issn.2471-2140.jaa-21-3747

A proprietary formulation was designed that consisted minerals (zinc, magnesium, iron, calcium, selenium, and copper), vitamins (pyridoxine HCl, cyanocobalamin, ascorbic acid, and cholecalciferol), Panax ginseng extract, and cannabidiol isolate. The study was aimed to assess the potential of the novel test formulation (blessed) and per se to the animals with the Trivedi Effect® in male Sprague Dawley (SD) rats, fed with vitamin D3 deficiency diet (VDD). The test formulation consisted above mentioned ingredients was divided into two parts. One part was left aside as the untreated test formulation without any Biofield Treatment, while the other part was defined as the Biofield Energy Treated sample, which received the Biofield Treatment by renowned Biofield Energy Healer, Mr. Mahendra Kumar Trivedi. The level of lipid peroxidation end product malondialdehyde (MDA) in liver tissues was significantly reduced by 34.59%, 34.91%, and 65.81% (p≤0.001) in test formulation treated with Biofield Energy (G5), Biofield Treated test formulation from day -15 (G7), Biofield Treatment per se with Biofield Treated test formulation from day -15 (G8) groups, respectively as compared to the disease control group (G2). Moreover, level of catalase enzyme in liver tissues was also increased by 8.64% in the G7 group as compared to the G2 group. Besides, in brain homogenate the level of glutathione peroxidase (GPx) was significantly increased by 433.94%, 266.97%, 133.94%, 467.89%, and 489.86% in the G5, Biofield Energy Treatment per se to animals from day -15 (G6), G7, G8, and Biofield Treatment per se animals plus untreated test formulation (G9) groups, respectively than G2. Antioxidant enzyme like superoxide dismutase (SOD) was significantly (p≤0.001) increased by 14.16% in the G9 group as compared to the G2 group. Allover, results signified that the Biofield Treated test formulation significantly increased antioxidative parameters, could be able to give support against oxidative stress induced by free radical and to maintain a good human health.

Antioxidant Activity Open Access

Evaluation of Anti-oxidation and Therapeutic Effect of Biofield Energy Healing Based Novel Test Formulation Using TNBS (Tri Nitro Benzene Sulfonic Acid) - Induced Ulcerative Colitis in Sprague Dawley Rats

Feb 2021 DOI 10.14302/issn.2471-2140.jaa-21-3704

The aim of the study was to evaluate the antioxidant potential of Biofield Energy Healing (the Trivedi Effect®) based test formulation using TNBS-induced colitis animal model. Each ingredient of the test formulation was divided into two parts. One part was denoted as the control without any Biofield Energy Treatment, while the other part was treated with Biofield Energy Treatment by Mr. Mahendra Kumar Trivedi and defined as the Biofield Energy Treated test formulation. The colon tissue was used for the estimation of anti-oxidation activity for catalase (CAT), glutathione (GSH), lipid peroxidation (LPO) product, myeloperoxidase (MPO), superoxide dismutase (SOD), and glutathione peroxidase (GPx) using standard procedure. The antioxidant results showed that the CAT level was significantly increased by 95.4% (p≤0.001), 72.3%, 47.6%, and 13.9% in the Biofield Energy Treated test formulation (G5), Biofield treatment per se to animals (-15 days)(G6), Biofield Energy Treatment per se to animals plus Biofield Energy Treated test formulation (-15 day) (G8), and Biofield Energy Treatment per se to animals plus untreated test formulation (G9) groups, respectively as compared to the untreated test formulation group (G4). Further, colon GSH activity was found to be significantly increased by 23.2% (p≤0.05) 15.4%, and 15.5%, in G5, G6, and G9 groups, respectively with respect to G2 group. In addition, colon LPO activity data suggested that it was decreased by 12%, 17%, 18%, and 19.1% in G5, G6, Biofield Energy Treated test formulation (-15 day) (G7), and G8 groups, respectively, as compared with the G2 group. The level of MPO showed a significant (p≤0.001) reduced level by 27.9%, 22%, 14.5%, 16.6%, and 25.3% in G5, G6, G7, G8, and G9 groups, respectively as compared with the G2 group. The level of colon SOD was increased by 16.7% and 14.2% in the G5 and G9 groups, respectively as compared with the untreated test formulation, G4 group. Colon GPx level was increased by 177.6%, 71.4%, 71.4%, 161.2%, and 114.3% in G5, G6, G7, G8, and G9 groups, respectively as compared with the G2 group. Thus, it can be concluded that the Trivedi Effect®-Consciousness Energy Healing based test formulation and Biofield Energy per se has significant colon anti-oxidation profile, which can be used to improve many autoimmune and inflammatory diseases, stress management and prevention, and anti-aging by improving overall health.

Ophthalmic Science Open Access

Resveratrol Prevents Cataract Formation by Inhibiting Pro-inflammatory Mediator-induced Dysregulation of Lens Calcium

Apr 2020 DOI 10.14302/issn.2470-0436.jos-20-3303

The effect of resveratrol, a free radical scavenger, during cataract development was evaluated in the Wistar rat pup model. This study investigated the possible free radical scavenging potential of resveratrol at 40 mg/ kg body wt dose in selenite-induced cataract in rat pups. Intraperitoneal injection of sodium selenite (15 µm mol/ kg body wt) in 8 to 10 day old rat pups lead to severe oxidative stress in the tissues evidenced by decreased antioxidants and increased lipid peroxidase, nitric oxide, superoxide anion, hydroxyl radical generation, inducible nitric oxide synthase (iNOS) as well as nuclear factor kappa B (NF-kB) expression levels that probably led to cataract formation. Selenite exposure also caused an increase in total calcium in the eye lens and significantly inhibited the activity of Ca2+ ATPase but not Na+/ K+ ATPase or Mg2+ ATPase. However, both pre- and co-treatments with resveratrol, but not post-treatment, led to an increase in antioxidant levels with a concomitant reduction in oxidative stress and also rescued the selenite-mediated increase in lens Ca2+ and inhibition of Ca2+ ATPase activity in the eye lens. The results of this study demonstrate antioxidants decrease and increase in free radical generation triggered by selenite causes the inactivation of lens Ca2+ ATPase leading to a rise in intracellular Ca2+ level. Resveratol treatment was able to prevent selenite-induced oxidative stress and in turn the inhibition of lens opacification. Thus, resveratrol has the potential to function as an anti-cataractogenic agent, possibly by preventing free radical-mediated accumulation of Ca2+ in the eye lens.

In Vitro Assessment of Antioxidant Enzymes, Phenolic Contents and Antioxidant Capacity of the Verdolaga (Portulacaceae)

Jan 2020 DOI 10.14302/issn.2379-7835.ijn-19-3144

In this study, the antioxidants and photosynthetic compounds of Verdolaga were examined. Compounds were extracted from distinctive segments of the verdolaga using various solvents such as methanol (40, 60, 80%), ethanol (40, 60, 80%), acetone (40, 60, 80%), and deionized water. The use of 80% methanol led to the highest extracted concentration of phenolic substances and flavonoids. The extracted products (Leaves, Stem strips, and Root strips) were evaluated for their radical scavenging capabilities with DPPH (IC50= 22.26, 20.56, and 32.10), and ABTS (IC50= 2.86, 3.70, and 5.24), reducing power (EC50= 15.70, 16.39, and 21.69), and peroxide scavenging activity (1C50= 1.717, 2.937, and 3.255), respectively. The extracted products were analyzed by a gas chromatography-mass spectrometer. Peroxidase, catalase, and polyphenol oxidase assays were completed for the crude extract of verdolaga’s leave, stem strips, and root strips. As indicated by these tests, extracts of the verdolaga’s roots, stems and leaves using 80% methanol yielded high antioxidant activity. The most elevated concentrations of extracted chlorophyll, lycopene, and carotenoids were from the leaves and the highest concentration of extracted tannin was noted from strips of stems. The highest measures of peroxidase and polyphenol oxidase were identified in root strips and the highest units of catalase was identified in leaves.

Triacontanol Alleviated Nickel Toxicity in Maize Seedling by Controlling Its Uptake and Enhancing Antioxidant System

Oct 2019 DOI 10.14302/issn.2638-4469.japb-19-3051

Triacontanol (TRIA) role in improving growth, physiological activities and tolerance against abiotic stresses has been reported. Yet, the mechanism by which TRIA executes its effects remains elusive. This work therefore studied the possible role of TRIA exogenous application in counteracting the adverse effects of nickel (Ni) treated maize seedlings. Maize seedlings (15-day-old) were grown in washed sand irrigated with nutrient solution provided with 100 μM NiCl2. Two concentrations of TRIA (25 and 50 µM) were applied twice as a foliar spray for Ni-stressed seedlings. Shoot and root growth attributes, Ni content, and antioxidant defence systems of maize seedlings were determined. Ni treatment reduced the shoot and root length and biomass, causing necrosis of the old leaves,greater reduction was shown in the roots. The shoot and root length was negatively correlated with their Ni content, which was consistent with their content of H2O2, but not with their malondialdehyde (MDA) content. As the roots had the greatest Ni content, maximum peroxidase (PX) and glutathione reductase (GR) activity as well as the highest ascorbic acid (ASA) and reduced glutathione (GSH) content were observed in the roots. The Ni-induced deleterious effects were alleviated by foliar application of TRIA concentrations. Also, TRIA treatment minimized root Ni content, whereas it maintained the shoots unharmed by Ni. Such mitigative effects of TRIA are explained by its key role in enhancing antioxidant capacity (expressed as IC50), increased PX and ascorbate oxidase (AO) activity, GSH, and total phenolic contents.

Obesity Management Open Access

Interaction Between Ator and Fennel in the Treatment of Obesity in Rats

Oct 2019 DOI 10.14302/issn.2574-450X.jom-19-2852

Obesity can be defined as a condition of abnormal or excess fat accumulation in adipose tissue, to the extent that health may be impaired. Fennel is one of the oldest spice plants which widely grows in arid and semi-arid and due to its economic importance and pharmaceutical industry usage. This plant has anti-inflammatory and analgesic effect and is effective in gastrointestinal disorder treatment. The aim of the present study was to evaluate the phytochemical characteristics and therapeutic properties of this medicinal plant. The current study demonstrates that the alteration induced by high fat diet causing changes in blood parameters. These changes are exhibited through a decrease in RBCs, Ht, Hb and platelet and these changes could be due to oxidative stress, which lead to lipid peroxidation in RBCs membranes, auto oxidation of hemoglobin. As regards the total WBCs, lymphocytes and monocytes showed marked decrease. While a distinct increase in the percentage of neutrophils and eosinophil. The present, demonstrates that rats treated with (fennel), (ator) and (fennel with ator) exposure provided significant protection to the altered hematological variables. The effect of the treatment with fennel and ator more effect than fennel only and ator only. The finding of this study indicates that the concentration of Malondialdehyde (MDA) and Myeloperoxidase (MPO) in liver homogenates of the fennel and ator group significant decrease than group (3) and group (4) and the obese group. There is a growing awareness that obesity is a prime risk factor for the development of dyslipidemia profile and that oxidative stress may play a role in various adverse effects of obesity.

Effect of Bone Marrow and Adipose Mesenchymal Stem Cells on Rat Intestinal Injury Induced by Methotrexate

Nov 2018 DOI 10.14302/issn.2640-6403.jtrr-18-2449

Methotrexate (MTX) is an anti-metabolite in cancer chemotherapy and is associated with various toxicities assigned to inflammation and oxidative stress. The present study was undertaken to corroborate the therapeutic effects of bone marrow mesenchymal stem cells (BM-MSCs) and adipose-derived mesenchymal stem cells (AD-MSCs) in MTX-induced intestinal toxicity in experimental animals as compared with dexamethasone (Dex). Rats were divided into five groups: I-Normal control group, II- MTX (14 mg/kg, as a single dose/week for 2 weeks), III & IV- BM-MSCs & AD-MSCs (2 × 106 cells/rat, 1 week after last dose of MTX), respectively, plus V- Dex (0.5 mg/kg/ for 7 days, 1 week after last dose of MTX). MTX induced marked intestinal elevation of interleukin-6, total oxidant, and nitrite/ nitrate, caspase-3 contents and myeloperoxidase activity, along with the reduction of reduced glutathione content and catalase activity. In conclusion, the positive modulation of MTX toxicity could be attributed to the free radical scavenging, anti-inflammatory and antiapoptotic potential of BM-MSC and AD-MSCs which will possibly make them as remarkable hopeful for the treatment of intestinal injury.

Enzymes Open Access

Using A “Superrooting”Cultivar of Taxus Chinensis Var. Mairei to Unravel Antioxidative Enzymes’ and Micrornas’ Role on Adventitious Rooting

May 2018 DOI 10.14302/issn.2690-4829.jen-18-2048

Rooting of cuttings is very important for production of economically important plants. We produced thousands of plantlets in Taxus chinensisvar. mairei using the technology of rooting of cuttings and identified two types of rooted cuttings, one with low rate of root formation and another with high rate of root formation. To determine the physiological role of antioxidative enzymes and microRNAs during the process of rooting, we measured the levels of these antioxidative enzymes and microRNAs in the stem portion, needles, roots, and basal portion of cuttings. Compared to the cuttings with low rate of root formation, cuttings with high rate of root formation had higher expression of polyphenoloxidase (PPO), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APOX), glutathione reductase (GR), and superoxide dismutase (SOD) in the adventitious roots and basal portion of the rooted cuttings 77 days after planting. In the basal portion of cuttings, the content of thiobarbituric acid reactive substances (TBARS) and total phenols were decreased and the content of antioxidants was increased, but they did not changed in the needles of cuttings during planting. Analysis of microRNAs by quantitative realtime PCR demonstrated that expression of miR162, miR408, and miR857 increases in the basal portion of cuttings, but not in the stem portion of cuttings, 77 days after planting. Expression of miR408 and miR857 were also increased in the needles of cuttings 77 days after planting. Changes of these antioxidative enzymes and microRNAs associated with the rooting features of T. chinensisvar. maireicuttings and their functions have been discussed.

Regulation of Expression of Reactive Oxygen Intermediates During Plasmodium Infection to Reduce Immunopathology Provides a Possible Antioxidant Adjuvant to Enhance Anti-Malarial Drug Therapy

Aug 2017 DOI 10.14302/issn.2690-4721.ijcm-17-1676

Malaria is a mosquito-transmitted infectious disease caused by intracellular protozoan parasites of the genus Plasmodium. In the absence of prompt and appropriate treatment contraction of primary infection by a human being often represents a medical emergency since it may progress rapidly to life-threatening complications. Exposure to parasites activates the immune system resulting in, among other effects, the release of reactive oxygen intermediates (ROI). This has the potential to induce oxidative damage, thereby causing cellular destruction, and hence to have a severe effect on vital organs of the body. Overexpression of ROI leads to immunosuppression and is a causal factor in the development of malaria-related disease symptoms. However, the body possesses various defence mechanisms, notably including the production of antioxidants, which are capable of reducing the cellular effects of ROI. Antioxidants are either sourced exogenously from the diet or synthesized through different intracellular mechanisms. Antioxidants that include glutathione peroxidase, catalase, EDTA and vitamin C suppress the initial production of ROI. Others such as uric acid, superoxide dismutase and vitamin E may also inhibit potentially damaging products of ROI metabolism. Current anti-malarial drugs often have damaging side-effects, as exemplified by memory impairment following treatment for cerebral malaria. Recent studies have explored the potential use of antioxidants alone or in combination with anti-malarials as a therapeutic means to negate Plasmodium-induced oxidative stress and its associated metabolic complications. It is indicated that when utilized in an adjuvant capacity antioxidants of natural and synthetic origin may improve anti-malarial therapy by causing less damage to the host during malaria infection.

Antioxidant Activity Open Access

The antioxidant and hepatoprotective activities of two tea polysaccharides

Aug 2017 DOI 10.14302/issn.2471-2140.jaa-17-1541

In the present study, we investigated the chemical compositions, in vitro antioxidant and in vivo hepatoprotective activities of two tea polysaccharides (TPS), which were extracted from two different tea cultivars, Yingshuang (Camellia Senesis, T01) and Yunnan Dayezhong (Camellia Senesis, T09). Compared with T09-TPS, T01-TPS had lower contents of neutral sugar, protein, uronic acid and polyphenol. However, T01-TPS showed stronger scavenging abilities for transient free radicals of hydroxyl radical and superoxide anion radicals and lipid peroxidation inhibition effect, but weaker scavenging ability for stable free radical of DPPH. For hepatoprotective activity in vivo, the results demonstrated that both T01-TPS and T09-TPS could significantly prevent the increase of serum alanine aminotransferase and, aspartate aminotransferase levels, decrease the liver index, reduce the formation of malonydialdehyde and enhance the activities of superoxide dismutase, glutathione peroxidase and peroxidase in carbon tetrachloride-induced liver injury mice. These results suggest that T01-TPS and T09-TPS have potent antioxidant and hepatoprotective activities.

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