Increase In Antioxidant Power Research Articles

A Novel Strategy to Enhance Antioxidant Content in Saccharomyces Cerevisiae Based on Oxygen Pressure.

Antioxidant foods represent a potent lever to improve diets while creating value. Yet, their cultivation is often tied to a specific area and climate, limiting availability and increasing market cost. Therefore, microorganism-based antioxidant production emerges as a promising technology to solve these problems. In this view, a novel process was investigated for antioxidant accumulation in yeast culture. S. cerevisiae cells were exposed to various hyperbaric air conditions from 1 to 9 bar (A). Yeast cultures exhibited an increased reactive oxygen species content, which induced oxidative defense expression. After a few hours, reactive oxygen species levels decreased while antioxidant contents remained high, leading to a net increase in antioxidant power. At 6 bar (A), yeast achieved the highest net antioxidant power (phenolics content +48.3 ± 18.6 %, reducing power +120 ± 11.4 %) with an acceptable growth rate (0.27 h-1). Regarding time evolution, a 2 h exposure seems to be the optimum: cells have the lowest reactive oxygen species level while their antioxidant power is increased. From a biotechnological perspective, this finding highlights air pressure as an antioxidant-manipulating stress strategy. Moreover, the proposed process led to a patent that could potentially reduce energy and chemical consumption in such antioxidant accumulation processes.

Effect of seeds roasting time on physicochemical properties, oxidative stability, and antioxidant activity of cactus ( Opuntia ficus‐indica L.) seed oil

Cactus (Opuntia ficus-indica L.) seed oil, which is extracted from prickly pear fruit seeds, might constitute an alimentary source of substances of nutraceutical value. Physicochemical properties, chemical composition, antioxidant activity, and oxidative stability of prickly pear seed oil prepared from unroasted seeds were evaluated and compared with those of oil that was prepared from seeds roasted for different times. Prolonged roasting time had no significant influence on the protein content of the seeds. However, an increase in total phenolic compounds was observed from 225.9 mg GAE/100 g oil to 362.7 mg GAE/100 g oil after 40 min of roasting at 110℃. Consequently, an increase in antioxidant power which will induce a better oxidation resistance was found by the 1.1-diphenyl-2-picrylhydrazyl method expressed as EC50 value that was reduced from 0.6 to 0.1 mg/ml. No significant change was observed in triacylglyceride and fatty acid composition, whereas tocopherol (512.8 to 542.1 mg/kg after 40 min of roasting) and sterol (8,292 to 8,629 mg/kg after 40 min of roasting) levels increased. Oxidative stability increased remarkably from 3.1 to 7.6 hr after 40 min of roasting with the increase in roasting time. The current study revealed that prickly pear seeds and the resulting oil have excellent nutritional qualities that were significantly elevated after roasting. Practical applications Cactus seed oil is one of the most expensive vegetable oils and roasting of the seeds before pressing can help to improve not only the sensory quality of the oil but also the oxidative stability. Therefore, it is important to know more about the influence of roasting time on the quality of the oil. With this information, it is possible to optimize the roasting process regarding oil stability but also the release of bio-active compounds such as tocopherols or phenolic compounds. Overall, this will significantly improve the acceptance of this oil.

Melatonin modulates swine luteal and adipose stromal cell functions.

Based on our previous study in follicles, the first aim of this work was to evaluate the effect of melatonin in the swine corpus luteum (CL). Luteal cells were exposed to 10 and 20pg mL-1 melatonin. We evaluated the effect on proliferation (bromo-deoxy-uridine uptake), steroidogenesis (progesterone) and redox status by means of Griess test (nitric oxide production), WST-1 test (superoxide anion generation) and FRAP test (non-enzymatic antioxidant power). The results showed a significant increase in antioxidant power, as well as a reduction in the other parameters analysed. These data and the expression of MT2 observed in luteal cells allow us to hypothesise a physiological role of melatonin in the regulation of CL functionality. The reproductive function is dependent on energy reserves stored in adipose tissue. Therefore, we sought to verify the effect of melatonin on adipose stromal cells (ASCs). MT2 receptor expression was detected in ASCs and the presence of gene markers (PPARγ and leptin) before and after adipogenic differentiation was verified. The differentiation was significantly inhibited by melatonin, as well as cell viability. In conclusion, present results suggest that melatonin exerts a potential inhibitory action on luteal function and adipogenesis, possibly mediated by MT2.

Effects of apple polyphenols on oxidative stress and cerebral vasospasm after subarachnoid hemorrhage in a rabbit double hemorrhage model

Subarachnoid hemorrhage (SAH) is almost always caused by ruptured cerebral aneurysms, and the most serious complication after SAH is cerebral vasospasm. Oxidative stress due to free radicals released from subarachnoid hemorrhage clots causes cerebral vasospasm, as proven by animal experiments. Apple polyphenols have already been demonstrated to strongly suppress oxidized low-density lipoprotein (ox-LDL) and lectin-like oxidized LDL receptor-1 (LOX-1) derived from reactive oxygen species (ROS), and to improve cerebral vasospasm. However, it is unclear how apple polyphenol acts downstream of ROS. The purpose of this study is to reveal a more detailed mechanism of functioning for apple polyphenols in suppressing oxidative stress and cerebral vasospasm. Using the double-hemorrhage rabbit subarachnoid hemorrhage (SAH) model, we investigated the effect of apple polyphenols by measuring the basilar artery diameter, endothelial NO synthase (eNOS) expression, diacron reactive oxygen metabolites (d-ROM), biological antioxidant potential (BAP), and malondialdehyde (MDA). The mean diameter of the basilar artery in the apple polyphenol treatment group was significantly larger than in the SAH group (p < 0.01). The expression of endothelial nitric oxide synthase (eNOS), evaluated by immunohisto-chemistry in the apple polyphenol treatment group, was higher than in the SAH group (p < 0.05). The BAP test in the apple polyphenol treatment group showed a significant difference, while there was no significant difference in the values of d-ROM and MDA. The results of the present study revealed that apple polyphenol significantly improved cerebral vasospasm and eNOS. In spite of a significant increase in antioxidant power expressed by increased BAP, oxidative stress measured by the d-ROM value was not significantly suppressed. Either the number of experimental animals was not sufficient to reach statistical significance, or the eNOS increase due to apple polyphenols and suppression of vasospasm are attributable to pathways other than lipid oxidation detected by MDA.

The Protective Effect of Melissa officinalis L. in Visceral Hypersensitivity in Rat Using 2 Models of Acid-induced Colitis and Stress-induced Irritable Bowel Syndrome: A Possible Role of Nitric Oxide Pathway.

Background/AimsThe aim of present study is to estimate the effects of Melissa officinalis L. (MO) on visceral hypersensitivity (VH), defecation pattern and biochemical factors in 2 experimental models of irritable bowel syndrome (IBS) and the possible role of nitric oxide.MethodsTwo individual models of IBS were induced in male Wistar-albino rats. In the acetic acid model, the animals were exposed to rectal distension and abdominal withdrawal reflex, and the defecation patterns were determined. In the restraint stress model, the levels of TNF-α, myeloperoxidase, lipid peroxidation, and antioxidant powers were determined in the (removed) colon. Rats had been treated with MO, L-NG-nitroarginine methyl ester (L-NAME), aminoguanidine (AG), MO + AG, or MO + L-NAME in the mentioned experimental models.ResultsHypersensitive response to rectal distension and more stool defecation in control rats have been observed in comparison to shams. MO-300 significantly reduced VH and defecation frequency in comparison to controls. VH and defecation pattern did not show significant change in AG + MO and L-NAME + MO groups compared to controls. Also, significant reduction in TNF-α, myeloperoxidase, thiobarbituric acid reactive substances (TBARS), and an increase in antioxidant power in MO-300 group was recorded compared to controls. AG + MO and L-NAME + MO groups showed a reverse pattern compared to MO-300 group.ConclusionsMO can ameliorate IBS by modulating VH and defecation patterns. Antioxidant and anti-inflammatory properties along with its effect on the nitrergic pathway seem to play important roles in its pharmacological activity.

The antioxidant capacity of erythrocyte concentrates is increased during the first week of storage and correlated with the uric acid level.

Red blood cells (RBCs) suffer from lesions during cold storage, depending in part on their ability to counterbalance oxidative stress by activating their antioxidant defence. The aim of this study was to monitor the antioxidant power (AOP) in erythrocyte concentrates (ECs) during cold storage. Six ECs were prepared in saline-adenine-glucose-mannitol (SAGM) additive solution and followed during 43days. The AOP was quantified electrochemically using disposable electrode strips and compared with results obtained from a colorimetric assay. Haematological data, data on haemolysis and the extracellular concentration of uric acid were also recorded. Additionally, a kinetic model was developed to extract quantitative kinetic data on the AOP behaviour. The AOP of total ECs and their extracellular samples attained a maximum after 1week of storage prior to decaying and reaching a plateau, as shown by the electrochemical measurements. The observed trend was confirmed with a colorimetric assay. Uric acid had a major contribution to the extracellular AOP. Interestingly, the AOP and uric acid levels were linked to the sex of the donors. The marked increase in AOP during the first week of storage suggests that RBCs are impacted early by the modification of their environment. The AOP behaviour reflects the changes in metabolism activity following the adjustment of the extracellular uric acid level. Knowing the origin, interdonor variability and the effects of the AOP on the RBCs could be beneficial for the storage quality, which will have to be further studied.

Promising effect of Magliasa, a traditional Iranian formula, on experimental colitis on the basis of biochemical and cellular findings

To investigate the efficacy of Magliasa, a traditional Iranian formula, on experimental colitis. After botanical authentication of herbal ingredients, formulation of Magliasa, quantitative determination of total glucosinolates and total phenolic content, and analysis of the thin layer chromatography profile were performed. Colitis was then induced in male rats by instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS) in all groups, aside from the Sham group. The experimental groups consisted of: the Sham group that received only normal saline; the Mag-50, Mag-100 and Mag-200 groups, which received 50, 100 and 200 mg/kg per day of Magliasa, respectively; the control group, which received vehicle water orally; the infliximab group, which received infliximab (5 mg/kg per day, subcutaneously); and the Dexa group, which received dexamethasone (1 mg/kg per day, orally). After completing the treatment period (2 wk), the rats were sacrificed, the colon was removed, its macroscopic and microscopic changes were recorded, and tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), total antioxidant capacity, myeloperoxidase (MPO), and lipid peroxidation (LPO) were assessed in colon homogenate. The mean value of total glucosinolates in one gram of Magliasa was 19 ± 1 μmol. The mean value of the total phenolic content was 293.8 ± 17.6 mg gallic acid equivalents per 100 gram of Magliasa. Macroscopic scores were significantly decreased in Mag-100 (1.80 ± 0.58, P = 0.019) and Mag-200 (1.20 ± 0.20, P = 0.001) compared to the control group (3.40 ± 0.24), although some inflammation and hyperemia were evident. Treatment of rats by dexamethasone (0.33 ± 0.21, P < 0.001) and infliximab (0.83 ± 0.31, P < 0.001) remarkably attenuated scores where mild hyperemia was observed macroscopically. In comparison to the control group (4.00 ± 0.32), only Mag-200 (1.60 ± 0.40) showed a significant decrease in colonic histopathological scores (P = 0.005). Minimal mucosal inflammation was observed in the Dexa group (0.67 ± 0.21, P < 0.001). The levels of TNF-α, IL-1β and MPO were significantly lower in all groups compared to the controls (P < 0.05). A significant decrease in LPO was seen in the Mag-200 (3.27 ± 0.77, P = 0.01) and Dexa (3.44 ± 0.22, P = 0.011) groups in comparison to the control group (6.43 ± 0.61). Only dexamethasone caused a significant increase in antioxidant power in comparison to the control group (346.73 ± 9.9 vs 228.33 ± 2.75, P < 0.001). Infliximab and different doses of Magliasa did not show any remarkable increase in antioxidant capacity (P > 0.05). The effect of Magliasa in all of mentioned parameters, except antioxidant capacity, was dose dependent. The effects of Magliasa in TNBS-induced colitis are encouraging and warrant clinical trials for further confirmation.

On the benefit of magnetic magnesium nanocarrier in cardiovascular toxicity of aluminum phosphide

The present study was designed to determine the effect of a new (25)Mg(2+)-carrying nanoparticle ((25)MgPMC16) on energy depletion, oxidative stress, and electrocardiographic (ECG) parameters on heart tissue of the rats poisoned by aluminum phosphide (AlP). (25)MgPMC16 at doses of 0.025, 0.05, and 0.1 median lethal dose (LD50 = 896 mg/kg) was administered intravenously (iv) 30 min after a single intragastric administration of AlP (0.25 LD50). Sodium bicarbonate (Bicarb; 2 mEq/kg, iv) was used as the standard therapy. After anesthesia, the animals were rapidly connected to an electronic cardiovascular monitoring device for monitoring of ECG, blood pressure (BP), and heart rate (HR). Later lipid peroxidation, antioxidant power, ATP/ADP ratio, and Mg concentration in the heart were evaluated. Results indicated that after AlP administration, BP and HR decreased while R-R duration increased. (25)MgPMC16 significantly increased the BP and HR at all doses used. We found a considerable increase in antioxidant power, Mg level in the plasma and the heart and a reduction in lipid peroxidation and ADP/ATP ratio at various doses of (25)MgPMC16, but (25)MgPMC16-0.025 + Bicarb was the most effective combination therapy. The results of this study support that (25)MgPMC16 can increase heart energy by active transport of Mg inside the cardiac cells.(25)MgPMC16 seems ameliorating AlP-induced toxicity and cardiac failure necessitating further studies.

In vitro and in vivo antioxidant potential of the methanolic extract of Cassia singueana Delile (Fabaceae) Lock leaves

The antioxidant activity of Cassia singueana Delile (Fabaceae) Lock methanol leaf extract was investigated in vivo and in vitro using malondialdehyde (MDA) test, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), and ferric reducing/antioxidant power (FRAP) photometric assays. The leaves have been of interest to researchers because of its use in the treatment of various disease conditions in Nigerian traditional medicine. C. singueana leaf extract gave a significant (P < 0.05) dose-dependent increase in antioxidant power with the FRAP assay. The DPPH assay showed 66% antioxidant activity at 400 μg/ml of the crude extract but ascorbic acid showed 79% at the same concentration. All doses (0.25, 0.5, and 1.0 g/kg) of the extract exhibited significant (P < 0.05) reduction in MDA value of test rats compared to control from the onset of the investigation up to day 56. Thereafter, the extract showed no protective activity against lipid peroxidation. These findings demonstrate that the extract has antioxidant effects on experimental models and validate its use in Nigerian traditional medicine for the treatment of peptic ulcer. Even in its crude form, the effects were comparable to that of ascorbic acid, a compound with proven antioxidant activity. This finding suggests that the extract could be a potential source of a novel antioxidant.

Effects of Hypericum perforatum extract on rat irritable bowel syndrome.

Context:In irritable bowel syndrome (IBS), disturbance of bowel motility is associated with infiltration of inflammatory mediators and cytokines into the intestine, such as neutrophils, myeloperoxidase (MPO), tumor necrosis factor alfa (TNF-α), and lipid peroxide.Aims:Regarding promising anti-inflammatory and anti-oxidative effects of Hypericum perforatum (HP) extract, besides its anti-depressant effect, this study was designed to evaluate the effects of HP in an experimental model of IBS.Settings and Design:IBS was induced by a 5-day restraint stress in rats. The HP extract was administered by gavage in doses of 150, 300, and 450 mg/kg for 26 days. Fluoxetine and loperamide were used as positive controls. Gastric emptying and small bowel and colon transit, besides the levels of TNF-α, MPO, lipid peroxidation, and antioxidant power, were determined in colon homogenates.Statistical Analysis Used:Data were analyzed by one-way ANOVA followed by Tukey's post hoc test for multiple comparisons.Results:A significant reduction in small bowel and colonic transit (450 mg/kg), TNF-α, MPO, and lipid peroxidation and an increase in antioxidant power in all HP-treated groups (150, 300, and 450 mg/kg) were seen as compared with the control group. Gastric emptying did not alter significantly when compared with the control group. Treatment with loperamide (10 mg/kg) significantly inhibited gastric emptying and small bowel and colonic transit, while flouxetine (10 mg/kg) decreased gastric emptying, TNF-α, MPO, and lipid peroxidation and increased the antioxidant power of the samples in comparison with the control group.Conclusions:HP diminished the recruitment of inflammatory cells and TNF-α following restraint stress not in a dose-dependent manner, possibly via inhibition of MPO activity and increasing colon antioxidant power, without any difference with fluoxetine. The HP extract inhibits small bowel and colonic transit acceleration like loperamide but has minimal effect on gastric emptying.