Ferric Reducing Ability Of Plasma Values Research Articles

Antioxidant Activity of Different Hop (Humulus lupulus L.) Genotypes.

The antioxidant activity (AA) of hop extracts obtained from different hop genotypes (n = 14) was studied. For comparison, the purified β-acids-rich fraction and α-acids-with-β-acids-rich fraction were also used to test the antioxidative potential. The AA of purified hydroacetonic hop extracts was investigated using the Ferric Reducing Ability of Plasma (FRAP), Oxygen Radical Absorption Capacity (ORAC) and Intracellular Antioxidant (IA) methods. The FRAP values in different hop genotypes ranged between 63.5 and 101.6 μmol Trolox equivalent (TE)/g dry weight (DW), the ORAC values ranged between 1069 and 1910 μmol TE/g DW and IA potential values ranged between 52.7 and 118.0 mmol TE/g DW. Significant differences in AA between hop genotypes were observed with all three methods. AAs were determined using three different methods, which did not highly correlate with each other. We also did not find significant correlations between AA and different chemical components, which applies both to AA determined using individual methods as well as the total AA. Based on this fact, we assume that the synergistic or antagonistic effects between hop compounds have a more pronounced effect on AA than the presence and quantity of individual hop compounds.

Does Oxidative Stress Along with Dysbiosis Participate in the Pathogenesis of Asthma in the Obese?

The most important environmental factor that can play a key role in the development of asthma in the obese is overproduction of reactive oxygen species (ROS). The aim of the study was to examine changes in the concentration of oxidative stress parameters in the lungs, bronchoalveolar lavage (BAL) fluid and blood of mice in models of asthma or/and obesity caused by high-fat diet (HFD). The concentrations of 4-HNE and isoprostanes in the lungs of the animals were measured. BAL fluid levels of hydrogen peroxide were marked. Additionally, thiobarbituric acid reactive substances (TBARS) and ferric reducing ability of plasma (FRAP) were used as biomarkers of oxidative stress in the blood. Administration of lipoic acid (LA), a probiotic with standard-fat diet (SFD, 10% fat) and low-fat diet (LFD, 5% fat) significantly decreased the concentration of 4-HNE as compared to the OVA (ovalbumin) + HFD group (p < 0.05). Treatment with low-fat diet or LFD in combination with apocynin insignificantly decreased H2O2 values as compared to the OVA + HFD group. Supplementation of probiotic with SFD and LFD significantly decreased the concentration of TBARS as compared to the OVA + SFD and saline + HDF groups (p < 0.05). Significantly lower concentrations of TBARS were also observed in the LA plus LFD group (p < 0.05) as compared to the OVA + HFD group. Low-fat diet with probiotic significantly increased the concentration of FRAP as compared to the obese mice (p = 0.017). Treatment with LFD in combination with LA significantly increased FRAP values as compared to the obese and obese asthmatic mice (p < 0.001).

Evaluation of Pro/Antioxidant Imbalance in Blood of Women with Polycystic Ovary Syndrome Based on Determination of Oxidized Low-Density Lipoproteins and Ferric Reducing Ability of Plasma Values.

We investigated selected pro/antioxidant parameters in a group of women with polycystic ovary syndrome (PCOS) divided according to age, body mass index (BMI), waist-to-hip ratio (WHR), homeostatic model assessment for insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (Quicki). We chose oxidized low-density lipoproteins (oxLDL-C) as a marker of oxidative stress and the ferric reducing ability of plasma (FRAP) as a marker of antioxidant status. In women with PCOS, the values of BMI, WHR, age and concentration of glucose significantly affected oxLDL-C concentration and FRAP values. FRAP correlated with oxLDL-C level in the whole group and in women who were insulin sensitive (HOMA-IR < 2.0). There was a negative relationship between the concentration of Anti-Müllerian hormone and both oxLDL-C and FRAP. Furthermore, the value of FRAP was inversely correlated with luteinizing hormone (LH), follicle-stimulating hormone (FSH) and androstenedione, whereas it was positively correlated with the LH/FSH ratio. The concentration of oxLDL and the value of FRAP are significantly associated with selected metabolic and hormonal parameters in the course of PCOS.

Effect of oligosaccharides on the antioxidant, lipid and inflammatory profiles of rats with streptozotocin-induced diabetes mellitus.

Prebiotics, gut microbiota-fermentable substances, delay the development of type I diabetes. In the present study, we investigated the effect of two prebiotics (galacto-oligosaccharides and xylo-oligosaccharides) on the antioxidant protection, lipid profile, and inflammatory activity of rats with streptozotocin-induced diabetes. The following markers were studied- malondialdehyde, 8-hydroxy-2'-deoxyguanosine, ferric reducing ability of plasma (FRAP), triacylglycerols, total cholesterol (TC), high-density lipoproteins, C-reactive protein (CRP), and interleukin-6. Diabetes was induced in male Wistar experimental rats by streptozotocin injection, while the non-diabetic controls were injected with saline. Afterward the oligosaccharides were administered orally to the experimental animals. The blood collected following the decapitation was analyzed by ELISA. A modified protocol was used only for measuring the FRAP values. The galacto-oligosaccharides and xylo-oligosaccharides lowered the malondialdehyde levels in the diabetic rats (p<0.05). The galacto-oligosaccharides decreased the serum levels of 8-hydroxy-2'-deoxyguanosine (p=0.01), while the xylo-oligosaccharides increased the FRAP (p<0.05) in the experimental animals. None of the oligosaccharides affected triacylglycerol and interleukin-6 concentrations, but the galacto-oligosaccharides decreased the TC and CRP levels in the diabetic animals. Both oligosaccharides exert a beneficial effect on the antioxidant protection of the diabetic rats, but have a minor effect on their lipid and inflammatory profiles.

Quantification of Flavonoids, Phenols and Antioxidant Potential from Dropped Citrus reticulata Blanco Fruits Influenced by Drying Techniques.

Physiologically dropped immature Citrus reticulata Blanco fruits are regarded as waste and discarded in the citrus orchard but are a good source of bioactive compounds including flavonoids, antioxidants and total phenols. A study was undertaken to identify and quantify these bioactive compounds and to investigate the influence of different drying techniques, namely freeze drying and hot air oven drying, on flavonoids namely flavanone glycosides, antioxidant potential and total phenol content in immature dropped fruits of Citrus reticulata Blanco. Flavonoids were quantified in high-performance liquid chromatography (HPLC). The antioxidant activity were investigated with three assays azino-bis [3-ethylbenzthiazoline-6-sulfonic acid]) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), Ferric Reducing Ability of Plasma (FRAP) and total phenol content was determined. Freeze dried samples of 12 and 14 mm size retained maximum hesperidin flavonoid content (27.03% and 27.20%) as compared to the hot air dried samples (17.99%) and retained higher phenolic content ranged from 50.54–54.19 mg GAEL−1. The antioxidant activity in freeze dried fruits was from 12.21–13.55 mM L−1 Trolox and 15.27–16.72 mM L−1 Trolox with ABTS, DPPH assay and FRAP values ranging from 7.31–9.07 mM L−1 Trolox. Significant positive correlation was found between the flavonoid hesperidin with antioxidant assays and total phenolic content (TPC). The results showed that waste citrus fruits can act as potential source of bioflavonoids, especially hesperidin, and antioxidants for pharmaceutical as well as nutraceutical industry.

Evaluation of the antioxidant capacity and bioactive compounds of banana passionfruit (Passiflora mollissima) and black cherry (Prunus serotina)

Objective: To determine the content of bioactive compounds and antioxidant capacity of the banana passionfruit(Passiflora mollissima) and black cherry (Prunus serotina). Materials and methods: An analytical, experimental, longitudinal and prospective study. The black cherries and bananapassionfruits were collected in the Cusco, Moquegua and Arequipa regions. The content of phenols and flavonoids weredetermined using the Folin–Ciocalteu reagent and aluminum chloride method, respectively. The antioxidant activity wasevaluated using the ferric reducing ability of plasma (FRAP), 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and thiobarbituric acid reactive substance (TBARS) techniques. Albino rats classified into a negative control group, a positive control group andfour experimental groups were used to study the hepatoprotective effect of the fruits. Results: Banana passionfruits from the Cusco region (Quechua) showed the highest concentration of total phenols(584.94 ± 134.62 mg GAE/100 g) and flavonoids (445.62 ± 7.94 mg QE/100 g). Concerning the DPPH radical, the IC50value of banana passionfruits from the Arequipa region (Yunga) was found to be 0.41 ± 0.01 mg/mL. Banana passionfruitsfrom the Cusco region (Quechua) showed the highest FRAP value (8.38 ± 0.32 mmol Fe2+/100 g). Black cherries from theArequipa region (Yunga) had the highest concentration of total phenols (181.81 ± 34.1 mg GAE/100 g) and flavonoids(205.18 ± 77.8 mg QE/100 g). They also showed a significant antioxidant activity regarding the DPPH (2.1 ± 0.01 mg/mL), whilethe antioxidant capacity of black cherries from the Cusco region (Quechua), which was evaluated with the FRAP method,achieved a value of 1.59 ± 0.2 mmol Fe2+/100 g. The observed differences were statistically significant. Banana passionfruitsshowed a better hepatoprotective effect than black cherries.Conclusions: Banana passionfruits from the Cusco region (Quechua) are an important source of antioxidant compoundsand show a high antioxidant capacity (FRAP), while black cherries from the Arequipa region (Yunga) have a high contentof antioxidant compounds and a higher antioxidant capacity (DPPH).

Effects of Supplementing Rumen-Protected Methionine and Lysine on Milk Performance and Oxidative Status of Dairy Ewes.

There is limited information on the impact of dietary supplementation with separate rumen-protected (RP) amino acids (AA), or with their combination, on ewes’ oxidative status. Sixty ewes were divided into five groups; C: basal diet (control); M: basal diet + 6 g/ewe RP methionine; L: basal diet + 5 g/ewe RP lysine; LML: basal diet + 6 g methionine and 5 g lysine/ewe; and HML: basal diet + 12 g methionine + 5 g lysine/ewe. Milk’s fat content increased in RP-AA fed ewes, while that of protein in M and L only. In blood plasma, the malondialdehyde (MDA) content was reduced in the M, LML, and HML compared to C-fed ewes. An increase in glutathione transferase activity in the blood plasma of the M and LML compared to the C and HML-fed ewes were found. In milk, lower values of the ferric reducing ability of plasma (FRAP) in the LML and HML-fed ewes and of 2,2′-Azino-bis 3-ethylbenzthiazoline-6-sulfonic acid (ABTS) in LML only, were found. Lysine increased milk’s FRAP values and MDA content. Both L and HML diets increased milk’s protein carbonyls content. Methionine improves the organism’s oxidative status, without adversely affecting milk’s oxidative stability. Lysine dietary inclusion affects negatively the oxidative stability of milk.

The effect of whole sesame seeds on milk chemical composition, fatty acid profile and antioxidant status in goats

Whole sesame seeds (WSS), although rich in linoleic acid, have not been studied for their impact on the milk fatty acid (FA) profile. Twenty-four goats were divided into three homogeneous subgroups. A control (CON) group and treated groups, in which WSS were incorporated in the concentrates of the CON at 5% (WSS5) and 10% (WSS10), respectively, by partial substitution of both soybean meal and corn grain, were evaluated. Significant increases in the milk fat and total solids contents of goats fed the WSS10 diet compared with the CON were found. In the milk of WSS10-fed goats, the proportions of long-chain fatty acids, monounsaturated fatty acids and unsaturated fatty acids (UFAs) were increased, while those of medium-chain fatty acids and saturated fatty acids (SFAs) were decreased compared with those of the CON group. Significant decreases in the proportions of short-chain fatty acids, in the SFA/UFA ratio and in the atherogenicity index value in milk of treated goats were observed. The proportions of C15:0 and C17:0 FAs in the blood plasma of WSS10-fed animals compared with CON-fed animals were reduced significantly. Superoxide dismutase and catalase activities increased significantly in the blood plasma of WSS10-fed goats compared with CON-fed goats. Additionally, in the treated goats, the protein carbonyls (PC) in blood plasma and both PC and malondialdehyde contents in milk declined significantly. A significant enhancement in the total antioxidant capacity [measured by the ferric reducing ability of plasma (FRAP)] in the milk of WSS10-fed goats compared with the CON was found. Similarly, an increase in the FRAP value of milk of WSS5-fed goats compared with CON-fed goats was observed. In conclusion, the highest inclusion level of WSS (WSS10) in goat diets improves the FA profile and the oxidative stability of milk and improves the organism's antioxidant status.

The effect of thyroid hormone status on selected antioxidant parameters in patients with Graves' disease and active thyroid-associated orbitopathy.

Oxidative stress has been implicated in the pathogenesis of thyroid-associated orbitopathy (TAO) in patients with Graves' disease (GD). This study assessed the effect of thyroid hormone abnormalities on selected antioxidant parameters in patients with active TAO. The study group consisted of 56 patients with GD and active TAO treated with antithyroid medication. Depending on the thyroid hormone level, they were subdivided into two groups: Group 1 - hyperthyroid patients (n = 34) and Group 2 - euthyroid patients (n = 22). The total oxidant status expressed as the ferric reducing ability of plasma (FRAP) as well as selected enzymatic and nonenzymatic components of the antioxidant system, including the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), and paraoxonase 1 (PON-1), as well as the levels of vitamin C, uric acid, and lipid peroxidation products: malondialdehyde (MDA) and conjugated dienes (CD) were assessed in all enrolled participants. The FRAP values in Group 1 were significantly higher than in controls. The FRAP values in Group 2 were lower than in Group 1 and higher than in controls. However, the differences were not significant. In Group 1, the activity of SOD and GPx, as well as serum levels of uric acid, MDA, and CD, were significantly higher than in controls. At the same time, serum PON-1 activity and vitamin C levels were significantly lower in Group 1 than in controls. In Group 2, the SOD activity as well as MDA and CD levels were non-significantly lower than in Group 1 and non-significantly higher than in controls. The activity of GPx in euthyroid patients with TAO was significantly higher than in controls. Hyperthyroidism is a significant contributor to oxidative stress in patients with active TAO, which manifests as upregulated lipid peroxidation and antioxidant system activation. Euthyroid state restoration leads to a relative reduction in activity and levels of most studied antioxidant parameters, which still remain above the normal values. The autoimmune inflammation of the orbital tissue seems to be a thyroid hormone status-independent modifier of oxidative stress.

Citral Protects Human Endothelial Cells Against Hydrogen Peroxide-induced Oxidative Stress.

Oxidative stress plays a major role in endothelial dysfunction. Citral is a monoterpene aldehyde with antioxidant properties. This study aimed to investigate the effect of citral on human umbilical vein endothelial cells (HUVECs) under hydrogen peroxide (H2O2)-induced oxidative stress. The cells were treated with citral (0.625-10 μg/mL) for 24 h before exposure to H2O2 (0.5 mM, 2 h). Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. The hydroperoxide concentrations and ferric reducing ability of plasma (FRAP) were measured in intra- and extracellular fluids. Pretreatment of HUVECs with citral at concentrations of 5 and 10 μg/mL significantly enhanced the cell viability in H2O2-induced cytotoxicity. It reduced intracellular hydroperoxide levels at the concentrations of 5 and 10 μg/mL and extracellular hydroperoxide levels at the concentrations of 2.5-10 μg/mL. Pretreatment with citral significantly increased the FRAP value in intra- and extracellular fluids at the concentration range of 1.25-10 μg/mL. Antioxidant and cytoprotective effects were found for citral against oxidative damage induced by H2O2 in human endothelial cells. However, more studies in this area are needed to assess its clinical value for prevention and treatment of cardiovascular diseases.

SEASONAL VARIATIONS IN ANTIOXIDANT CAPACITIES AND PHENOLIC CONTENTS OF TEA LEAF EXTRACTS

Objectives: The objective of the study was to estimate the seasonal variations in the antioxidant capacities, total polyphenol content (TPC), total flavonoid content (TFC), and tannin content (TC) of tea leaf extracts from two different plantation sites.&#x0D; Methods: Samples were collected from two tea gardens in Tuli and Ungma situated at N 26°39’19.3 E 094°39’22.7 and N 26°17’30.6 E 094°28’29.2, respectively, under the Mokokchung district of Nagaland, India. TPC, TFC, and TC from sample extracts were determined using Folin–Ciocalteu reagent, aluminum chloride colorimetric, and Folin–Ciocalteu assay. Apart from these, antioxidant capacities were analyzed using ferric reducing ability of plasma (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay.&#x0D; Results: The concentrations of total polyphenol, flavonoid, and tannin varied from 552.029±8.079 to 305.647±1.744 mg gallic acid equivalent/g, 238.770±0.508–148.457±1.653 mg catechin equivalent/g, and 26.453±0.485–20.173±0.173 mg tannic acid equivalent/g, respectively. FRAP and DPPH assay displayed value ranging from 2.564±0.023 to 1.074±0.023 mmol Fe(II) equivalent/g and 3.612±0.053–2.076±0.028 mmol Trolox equivalent/g. Significant seasonal variations in concentrations of these compounds were observed and a positive correlation between antioxidant capacities and phenolics of tea leaf extracts was established.&#x0D; Conclusion: Tea (Camellia sinensis (L.) O. Kuntze) has been regarded as a plant of immense medicinal and therapeutic value since time immemorial. The tea leaf extracts analyzed in this study gave high TPC, TFC, and TC, as well as high antioxidant activity in terms of DPPH and FRAP value. Studying such properties in tea leaves contributes more to our understandings of health benefit potentials in tea leaves and the quality of tea leaves on the basis of seasons and sites where they are planted.

Combined Multi-assay Evaluation of the Antioxidant Properties of Tree Bark

Abstract Wood logging generates considerable amounts of bark by-product, which are a potential antioxidant source well worth extracting and using. The present work compares the antioxidant properties of the bark of the following selected Hungarian forest tree species: white poplar (Populus alba L.), black locust (Robinia pseudoacacia L.), sessile oak (Quercus petraea Liebl.), black poplar (Populus nigra L.), silver birch (Betula pendula Roth), European larch (Larix decidua Mill.), scots pine (Pinus sylvestris L.), wild cherry (Prunus avium L.), European hornbeam (Carpinus betulus L.) and sweet chestnut (Castanea sativa Mill.). Inner and outer bark were investigated separately. Total polyphenol content (TPC) was determined by the Folin-Ciocâlteu method, whereas antioxidant capacity was assayed using the ferric reducing ability of plasma (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), and ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) methods. The overall antioxidant power of the samples was evaluated using a scoring system that combined the FRAP, DPPH, and ABTS assay results. The TPC levels did not always follow the FRAP, DPPH, and ABTS assay values. Differing reaction mechanisms and sample compositions are possible reasons for this. The presented scoring evaluation was suitable for the assessment and comparison of complex antioxidant properties of tree bark samples. According to the scores, inner bark showed higher scores compared to outer bark for most species with the exceptions of black poplar, black locust, white poplar, sweet chestnut, and European larch. The highest overall antioxidant capacities were determined in the inner bark of wild cherry and the outer bark of sweet chestnut. The species with the overall lowest scores were black locust and black poplar.

Fatty Acids Predominantly Affect Anti-Hydroxyl Radical Activity and FRAP Value: The Case Study of Two Edible Mushrooms.

Compared to plants, nowadays mushrooms attract more attention as functional foods, due to a number of advantages in manipulating them. This study aimed to screen the chemical composition (fatty acids and phenolics) and antioxidant potential (OH•, 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and ferric reducing ability of plasma (FRAP)) of two edible mushrooms, Coprinus comatus and Coprinellus truncorum, collected from nature and submerged cultivation. Partial least square regression analysis has pointed out the importance of some fatty acids—more precisely, unsaturated fatty acids (UFAs) followed by fatty acids possessing both short (C6:0 and C8:0) and long (C23:0 and C24:0) saturated chains—and phenolic compounds (such as protocatechuic acid, daidzein, p-hydroxybenzoic acid, genistein and vanillic acid) for promising anti-OH•, FRAP and anti-DPPH• activities, respectively. However, other fatty acids (C16:0, C18:0 and C18:3n3) along with the flavonol isorhamnetin are actually suspected to negatively affect (by acting pro-oxidative) the aforementioned parameters, respectively. Taken together, design of new food supplements targeting oxidative stress might be predominantly based on the various UFAs combinations (C18:2n6, C20:1, C20:2, C20:4n6, C22:2, C22:1n9, etc.), particularly if OH• is suspected to play an important role.

Clinical Biomarkers for Diagnosis of Damages in Individuals with Long-Term Exposure to X-Rays.

To determine altered manifestation of plasma proteins in X-rays technicians who are regularly exposed to low doses of radiations over a long period during their job. Descriptive study. District Headquarters Hospital and Mufti Mahmood Memorial Teaching Hospital; from January 2017 to January 2018. The study enrolled 70 individuals consisting of 50 X-ray technicians working 8 to 12 hours/day for five days per week and 20 unexposed healthy controls. The serum protein expression pattern (concentrations of various serum proteins) was evaluated through cellulose acetate electrophoresis and serum antioxidant status was measured through ferric reducing ability of plasma (FRAP) assay. The antioxidant assay showed significantly low trolox-equivalent antioxidant capacity (TEAC) status and FRAP value in X-ray technicians as compared to controls (p<0.001). Analysis of serum protein demonstrated a significantly reduced concentrations of albumin (p<0.001) and elevated level of the Ɣ-globulins (p<0.001), while other globulins fractions like α1 and β remain unchanged. There was a strong negative correlation (p<0.001) according to Pearson coefficient (r=87%⁽⁻⁾) between albumin and Ɣ-globulins fraction. Whereas, a positive correlation (p<0.001) (r=46%⁽⁺⁾) between alpha 1 globulin and albumin fraction was observed. A correlation between other globulin fractions and albumin was found statistically significant (p<0.001). Elevated serum gamma globulins may be a potential protein biomarker for triage and detection of X-radiation induced damages.

Protective properties of Myrtus communis extract against oxidative effects of extremely low-frequency magnetic fields on rat plasma and hemoglobin

Purpose: This study investigates the protective properties of Myrtus communis extract against the oxidative effects of extremely low-frequency magnetic fields (ELFMF). Also, this study is aimed to analyze the conformational changes of hemoglobin, oxidative damages to plasma proteins and antioxidant power of plasma following exposure to ELFMF.Materials and methods: Adult male rats were divided into 3 groups: (1) control, (2) ELFMF exposure, and (3) ELFMF exposure after M. communis extract administration. The magnetic field (0.7 mT, 50 Hz) was produced by a Helmholtz coil for one month, 2 hours a day. The M. communis extract was injected intraperitoneally at a dose of 0.5 mg/kg before exposure to ELFMF. The oxidative effects of ELFMF were studied by evaluating the hemoglobin, methemoglobin (metHb) and hemichrome levels, absorption spectrum of hemoglobin (200–700 nm), oxidative damage to plasma proteins by measuring protein carbonyl (PCO) levels and plasma antioxidant power according to the ferric reducing ability of plasma (FRAP). The mean and standard errors of the mean were determined for each group. One-way ANOVA analysis was used to compare the means of groups. The significance level was considered to be p < .05. Moreover, artificial neural network (ANN) analysis was used to identify the predictive parameters for estimating the oxyhemoglobin (oxyHb) concentration.Results: Exposure to ELFMF decreased the FRAP which was in concomitant with a significant increase in plasma PCO, metHb and hemichrome concentrations (p < .001). Oxidative modifications of Hb were shown by reduction in optical density at 340 nm (globin-heme interaction) and 420 nm (heme-heme interaction). Administration of M. communis extract increased FRAP values and decreased plasma POC, metHb, and hemichrome concentrations. Also, a significant increase in Hb absorbance at 340, 420, 542, and 577 nm showed the protective properties of M. communis extract against ELFMF-induced oxidative stress in erythrocytes. ANN analysis showed that optical absorption of hemoglobin at 520, 577, 542, and 630 nm and concentration of metHb and hemichrome were the most important parameters in predicting the oxyHb concentration.Conclusions: Myrtus communis extract enhances the ability of erythrocytes and plasma to deal with oxidative conditions during exposure to ELFMF. Also, ANN analysis can predict the most important parameters in relation to Hb structure during oxidative stress.

Oxidative stress among informal caregivers

Abstract Objective: to evaluate oxidative stress and non-enzymatic antioxidant defenses in informal caregivers, and correlations with anxiety, health satisfaction and quality of life. Method: a case-control analytical study was performed, where the case was represented by the main informal caregiver and the control was paired with individuals with identical characteristics to the case, but who were not informal caregivers. The following instruments were used: a sociodemographic questionnaire, the Beck anxiety scale and the WHOQoL-Bref. Oxidative stress was measured through blood by analysis of the Ferric Reducing Ability of Plasma (FRAP) and Thiobarbituric Acid Reactive Substances (TBARS) markets. Results: most informal caregivers were females. There was no difference in the degree of anxiety between the Case and Control groups. Among informal caregivers, 9.4% said they were very dissatisfied and 53.1% dissatisfied with their health. Most caregivers (43.8%) rated their quality of life as poor and 12.5% as very poor, while most controls rated it as good (68.8%). The TBARS and FRAP values were lower in the Case group than in the Control group. Conclusion: The informal caregivers, who were mostly women, defined themselves as dissatisfied or very dissatisfied with their health. Nevertheless, they did not manifest a higher degree of anxiety in comparison with the control population. In addition, they presented a lower degree of oxidative stress than the non-caregiving participants, perhaps due to a greater mobilization of the non-enzymatic antioxidant defenses present in the body.

English

Phytochemicals possessing free radical scavenging and antiproliferative activities play an important role in cancer chemoprevention. In this study, the ethanolic extracts prepared from fresh and dried leaves, bark, and seed skin of Pra (Elateriospermum tapos Blume.) were tested for their antioxidant activity using a ferric reducing ability of plasma (FRAP) assay. The antiproliferative activities against four human cancer cell lines, breast (MCF-7), colon (HT-29, HCT116) and cervical (HeLa) cancer cells, were examined using the MTT assay. Fresh leaf extract exhibited the greatest antioxidant activity by giving the greatest FRAP value, followed by bark, seed skin and dried leaf extracts, respectively, which were strongly correlated to their flavonoid content. Dried leaf extract with the highest total phenolic content exhibited the greatest antiproliferative activity against all cancer cell lines tested. The growth of cervical cancer cell line (HeLa) was the most sensitive to all plant part extracts tested with IC50 values of 5.44 ± 0.57 µg/ml (fresh leaf), 5.41 ± 0.37 µg/ml (dried leaf), 6.39 ± 1.16 µg/ml (bark) and 7.03 ± 0.07 µg/ml (seed skin) at 72 h exposure. The non-cancer cell line (Vero) was more resistant to all plant part extracts when compared with the cancer cell lines. The ethanolic extracts of all E. tapos plant parts are promising for further purification and drug development. Key words: Antioxidant, antiproliferation, chemoprevention, Elateriospermum tapos, ethanolic extract.

Correlation of antioxidant activity of dried berry infusions with the polyphenols and selected microelements contents

Antioxidant activity was measured by ferric reducing ability of plasma (FRAP) assay in seven types of infusions prepared from commercial dried berry fruit products: Rosa canina , Vaccinium vitis-idaea , Hiphophae rhamnoides , Hibiscus sabdariffa and three fruit mixtures. Total polyphenols (TP), total anthocyanins and the polyphenolic compounds were determined by HPLC equipped with diode array detector. To estimate the amount of elements released from fruits into the water extracts, levels of Fe, Mn, Zn and Cu in dried samples and in infusions were determined by flame atomic absorption spectrometry. The correlation between polyphenols content and the antioxidant activities and the microelements in the infusions and the antioxidant activities were estimated using the Pearson’s correlation test. The results showed a high, positive and significant correlation (r = 0.9465) between the FRAP values and TP content, meaning that the concentration of phenolic compounds may be a good indicator of the reducing capacity in the infusions. Correlations varied (positive, negative and weak) between antioxidant and mineral extractability of berry infusions. Among the polyphenolic compounds, gallic acid contributed particularly to the antioxidant capacity of the studied samples (r = 0.563). The correlation of antioxidants, total polyphenols with mineral extractability showed the influence of antioxidant compound on mineral bioavailability. KEY WORDS : Mixed berry infusion, Antioxidant activity, Phenolic compounds, Microelements Bull. Chem. Soc. Ethiop. 2018 , 32(1), 1-12 DOI: https://dx.doi.org/10.4314/bcse.v32i1.1

The effect of different dietary levels of dl-methionine and dl-methionine hydroxy analogue on the antioxidant and immune status of young turkeys

ABSTRACTThe hypothesis postulating that the antioxidant and immunological effects of dietary methionine (Met) in young turkeys (1–8 weeks of age) can be differentiated by level and source of Met was investigated in this study. A total of 544 female Hybrid Converter turkeys were divided into four groups and fed diets in which Met content was tailored through supplementation with dl-methionine (dl-Met) or dl-methionine hydroxy analogue (MHA) to levels recommended by NRC (1994) (Groups dl-MetL and MHAL) and exceeding them by 50% (Groups dl-MetH and MHAH). Regardless of its source, the increased dietary Met content led to significantly higher body weight gains but had no effect on feed conversion rates. Moreover, an increased Met content lowered lipid peroxide concentrations in breast meat and increased selected indicators of the plasma antioxidant status like uric acid levels, activity of superoxide dismutase (SOD), glutathione (GSH) concentrations, the ferric-reducing ability of plasma (FRAP), increased immunoglobulin A (IgA) plasma levels and decreased interleukin 6 levels. In comparison with dl-Met, MHA decreased the activities of SOD and catalase, and GSH concentrations in plasma. A dosage by source interaction revealed that the lower MHA content was associated with the lowest plasma GSH concentrations, FRAP values and activities of SOD and catalase. The higher dietary MHA level resulted for most parameters similar values, except for a decrease in lipid peroxide concentrations and an increase in plasma IgA levels. It can be concluded that an increased dietary dl-Met and MHA content (about 150% of the recommendations given by NRC 1994) not only increased the growth rate of young turkeys but also improved their antioxidant status. MHA appears to be a less desirable source of dietary Met for young turkeys when the inclusion level of Met matches the current recommendations. Therefore, a further debate is needed to establish the dietary requirements for Met in poultry.

Three-phase partitioning for efficient extraction and separation of polysaccharides from Corbicula fluminea

Three-phase partitioning (TPP), which is a simple, efficient, and green bioseparation technique, was used to extract and separate polysaccharides from Corbicula fluminea (CFPS). The optimal parameters with a high yield of 9.32% were as follows: mass fraction of (NH4)2SO4, 20.0% (w/v); amount of t-butanol, 9.8mL; temperature, 35.3°C; extraction time, 30min; and pH 6.0. The purified CFPS after TPP consisted of d-glucose, d-glucosamine, and d-mannose in a molar ratio of 57.1: 5.6:1.0 with high purity (86.5%) and different molecular weights (1311.1 and 41.5–92.8kDa). Amino acid analysis, UV–vis absorption and Fourier transform-infrared spectra indicated that the purified CFPS was a proteoglycan with O-glycosidic bonds. Moreover, the purified CFPS possessed strong free-radical scavenging abilities and antioxidant activities in vitro. The obtained Trolox equivalent antioxidant capacity and ferric-reducing ability of plasma values were 95.01μmol Trolox/g sample and 38.30μmol Fe2+/g sample, respectively.