Evaluation Of Total Antioxidant Capacity Research Articles

Engineering an enzyme-like catalytic sensor for on-site dual-mode evaluation of total antioxidant capacity.

Anovel Fe-MoOx nanozyme, engineered with enhanced peroxidase (POD)-like activity through strategic doping and the creation of oxygen vacancies, is introducedto catalyze the oxidation of TMB with high efficiency. Furthermore, Fe-MoOx is responsive to single electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms related to antioxidants and can serve as a desirable nanozyme for total antioxidant capacity (TAC) determination. The TAC colorimetric platform can reach a low LOD of 0.512μM in solution and 24.316μM in the smartphone-mediated RGB hydrogel (AA as the standard). As proof of concept, the practical application in real samples was explored. The work paves a promising avenue to design diverse nanozymes for visual on-site inspection of food quality.

Colorimetric evaluation of total antioxidant capacity based on peroxidase-like nonstoichiometric Cu2-xSe nanoparticles

Antioxidants can help trap and neutralize free reactive oxygen species to reduce their damage. Thus, it is important to evaluate the content of antioxidants in foods and drugs. In this paper, a simple and sensitive colorimetric sensing platform for total antioxidant capacity (TAC) detection was developed based on the peroxidase-like nanozyme of nonstoichiometric copper selenide nanoparticles (Cu2-xSe NPs). The Cu2−xSe NPs with copper vacancy structures can accelerate intramolecular charge transfer and effectively catalyze the oxidation of chromogenic substrate colorless 3,3′5,5′-tetramethylbenzidine (TMB) into blue oxidized TMB (oxTMB), exhibiting that they had good peroxidase-like activity. Base on the good activity of Cu2−xSe NPs peroxidase mimics, a colorimetric sensing array combining UV–vis spectrometer, naked eye and smartphone-based digital image analysis for three typical antioxidant acids (ascorbic acid (AA), gallic acid (GA) and citric acid (CA)) were realized and the platform was successfully used for evaluating the TAC in the medical tablets, beverages and fruit juices.

Correlation Between Phytochemicals and Antioxidant Activities of Different Leaf Extracts of Entada rheedii

The main aim of this study was to determine Total Phenolic Content, Total Flavonoid Content, terpenoid content, steroid content and analyze the antioxidant activity of different leaf extracts of Entada rheedii. Correlation between antioxidant activities and total phenolic content, total flavonoids content, terpenoid content and steroid content were also analyzed. The total phenolic content in E. rheedii hexane, ethyl acetate, methanol, and aqueous leaf extracts were found to be 10.16 mg GAE/g, 24.73 mg GAE/g, 26.11 mg GAE/g, and 24.85 mg GAE/g sample dry weight respectively. The Total flavonoid content of E. rheedii hexane, ethyl acetate, methanol, and aqueous leaf extracts was found to be 8.433 mg QE/g, 8.730 mg QE/g, 8.607 mg QE/g, and 8.545 mg QE/g respectively. Hexane extract showed the highest steroid content at 32.75 g/mL, followed by ethyl acetate extract at 31.37 g/mL. The methanol extract and aqueous extract had the lowest steroid content at 22.2 g/mL and 21.21 g/mL, respectively. Terpenoid content was the highest in hexane extract with 62 mg/100 mg of dry extract, followed by the ethyl acetate extract with 45 mg/100 mg dry extract. The total content of terpenoids in the methanol extract was 25 mg/100 mg dry extract and the total content of terpenoids was lowest in the aqueous extract with 18 mg/100 mg dry extract. In 1-1-diphenyl- 2-picryl hydrazine Free Radical Scavenging (DPPH) Assay, the methanol extract displayed the highest antioxidant activity with an IC50 value of 173.581 μg/mL while the hexane extract showed the lowest activity; with IC50 value of 389.13 μg/mL. Reducing power assay was evaluated and aqueous extract was shown to possess the highest reducing power. Evaluation of total antioxidant capacity by phosphomolybdenum assay indicated that methanol extract had the highest antioxidant capacity. Significant correlations were also found between Total Phenol Content, Total flavonoid Content, and antioxidant activities of different leaf extracts of Entada rheedii.

A multi-line platinum nanozyme-based lateral flow device for the colorimetric evaluation of total antioxidant capacity in different matrices.

The evaluation of Total Antioxidant Capacity (TAC), namely the complete pattern of antioxidant species in a complex medium, is of major interest in many fields ranging from health monitoring to quality control in the food industry. In this framework, point-of-care (POC) testing technologies are a promising diagnostic solution for rapid on-site analyses, unlike laboratory based-assays, which are often limited by centralized analyses, time-consuming and costly procedures, and invasiveness in the case of health diagnostics. In this work, we developed a POC methodology that evaluates TAC in different matrices, exploiting the peroxidase-like properties of 5 nm platinum nanoparticles (PtNPs), combined with a colorimetric paper-based device. Notably, we designed and optimized a multi-line PtNPs-based Lateral Flow Assay (LFA), which relies on three sequential test lines with increasing concentrations of platinum nanozymes, to get a non-invasive, accurate, and fast (10 minutes) colorimetric evaluation of the body TAC in saliva samples. Furthermore, we employed the device as a prototype of a quality control tool in the food industry, for the determination of the TAC in fruit juices.

A polymetallic nanozyme with high peroxidase mimetic activity for rapid evaluation of total antioxidant capacity

Consumption of foods with high total antioxidant capacity (TAC) can reduce the risk of several illnesses in humans caused by the overproduction of pro-inflammatory cytokines in the body. Therefore, it is awfully important to build a rapid and sensitive platform for detecting TAC. In this work, a one-pot synthesized Bi0.3Fe1.7MoO6 with intrinsic peroxidase-like activity was made up for the shortcomings of natural enzymes for TAC detection. The peroxidase-like activity was evaluated by TMB chromogenic system in the presence of H2O2. Bi0.3Fe1.7MoO6 showed a higher affinity for H2O2 and TMB than that of natural horseradish peroxidase (HRP) and can be used to establish ascorbic acid (AA) sensing platform, which achieved a low detection limit (0.77 nM) and a good linear range (8–64 μM). The method has been proved to be applicable for the selective, stable, and reproducible TAC determination of food samples. Furthermore, the established TAC detection method applied to actual samples endows great potential for nutrition assessment.

Carbon dots as light-responsive oxidase-like nanozyme for colorimetric detection of total antioxidant capacity in fruits

Evaluation of total antioxidant capacity (TAC) in fruits is essential for dietary guidance and health monitoring. Here, we have exploited light-response carbon dots (CDs) as oxidase-like nanozyme to determine the TAC of fruits. The CDs possess excellent oxidase-like activity with light stimulation due to the accelerated intramolecular charge transfer caused by abundant electron donating/drawing groups in precursors. The scavenger experiment reveals that the catalytic intermediate could be hydroxyl radical, which can oxidize the colorimetric substrate. With the introduction of antioxidants, the oxidization of colorimetric substrate will be alleviated due to the scavenging of this intermediate by antioxidants. Based on this, we have successfully detected three antioxidants and obtained TAC of fruits with desirable results. This work affords a rapid, cost-effective and convenient analysis tool for TAC, as well as building a strong bridge between CDs and the development of photo-responsive oxidase-like nanozymes.

Automated electrochemical determination of beer total antioxidant capacity employing microdialysis online-coupled with amperometry

Electrochemical techniques are rarely applied for the evaluation of total antioxidant capacity of beers due to severe electrode inactivation (fouling) by adsorbed oxidation products of the species present in the samples. In this work, we show that microdialysis online-coupled with amperometry is suitable for beer analysis, permitting also an assay automation. The working electrode of the amperometric detector employs a carbon fiber microelectrode that is regenerated between the analyses by short (1 sec) rapid (50 Hz) sinusoidal potential cycling between 0 and 2.9 Vvs Ag/AgCl. This step, along with the sample cleanup by microdialysis effectively removes electrode fouling. The suitability of this approach for beer analysis was studied using eight different beers produced by international manufacturers. The results were compared with standard Kaneda diphenylpicrylhydrazil (DPPH) assay. Steady state currents, obtained at 600 mV vs Ag/AgCl correlate well with the results obtained with Kaneda method and thus can be used for quantification of beers' antioxidant capacities. HPLC-ED of microdialysates with and without DPPH treatment were employed to get an insight into DPPH reactivity with beer components.

Investigation on the Peroxidase-like Activity of Vitamin B6 and Its Applications in Colorimetric Detection of Hydrogen Peroxide and Total Antioxidant Capacity Evaluation.

The peroxidase-like activity of vitamin B6 (VB6) was firstly demonstrated by catalyzing the peroxidase chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) at the existence of H2O2. The influence of different factors on the catalytic property of VB6, including pH, temperature, VB6 concentration, and incubation time, were investigated. The steady-state kinetic study results indicate that VB6 possesses higher affinity to H2O2 than natural horseradish peroxidase and some other peroxidase mimics. Besides, the radical quenching experiment results confirm that hydroxyl radical (•OH) accounts for the catalytic process. Based on the excellent peroxidase-like catalytic activity of VB6, the colorimetric methods for H2O2 and gallic acid (GA) detection were developed by measuring the absorbance variance of the catalytic system. Under the optimal conditions, the linear ranges of the methods for H2O2 and GA determination with good selectivity are 50.0–600.0 μM and 10.0–50.0 μM, respectively. In addition, the developed method was applied in the detection of H2O2 in milk samples and evaluation of total antioxidant capacity of different tea infusions. This study may broaden the application prospect of VB6 in environmental and biomedical analysis fields, contribute to profound insight of the physiological functions of VB6, as well as lay foundation for further excavation of small-molecule peroxidase mimics.

Evaluation of Total Antioxidant Capacity in Al-Daura Oil Refinery Workers and Its Relation to Oral and Periodontal Conditions

Introduction: Total antioxidant capacity (TAC) is an important marker to be measured to explore the effect of oil fume on oral tissue. This study examined the effect of longtime exposure to oil fume on oral and periodontal tissue. Materials and Methods: A total of 52 participants consisted of four groups of 13 participants each. Oral examination and periodontal indices were taken. TAC was analyzed. Results: The study groups showed highly significant differences in plaque, gingival index, and clinical attachment level (P < 0.001) compared to the control. The older workers have shown the highest total antioxidant capacity levels. The oil group has expressed a significant lowest total antioxidant capacity level (P > 0.05) in comparison to the control. Oral lesions including ulcerations and white and red patches were absent in workers. Conclusion: Total antioxidant capacity is an important biomarker in the diagnosis of oral and periodontal diseases.

Ultrasensitive Pd nano catalyst as peroxidase mimetics for colorimetric sensing and evaluation of antioxidants and total polyphenols in beverages and fruit juices

Herein, we developed a new Pd NP from the aq extract of Elsholtzia blanda Benth. flower that showed efficient peroxidase mimetic activity. The catalytic mechanism was confirmed through colorimetric analysis. The optimizations of temperature, concentration, PH and time were done to find out the best procedure to implement the intrinsic catalytic activity in practical applications. Michaelis-Menten constants were evaluated for both TMB and H2O2 substrate to investigate the affinity of Pd NP towards them. Km was observed to be 42.35 mM for H2O2 and 0.0076 mM for TMB. Antioxidants were sensed using the peroxidase mimetic property up to nanomolar levels with a LOD = 0.78 nM for Gallic acid 0.85 nM for Tannic acid. The method was further implemented in comparing the radical scavenging power of different phenolic compounds. Smart-phone based analysis was done for observing the change in colour which could further be utilized as an analytical tool for study the antioxidant activity. R-Square values of 0.97 and 0.96 for detection of gallic acid and tannic acid respectively suggest good linearity of the plot. Lastly, the system was utilized in the evaluation of total antioxidant capacity (TAC) and total phenolic content (TPC) in commercially available juices and beverages.

Evaluation of total antioxidant capacity in human seminal plasma

Evaluation of total antioxidant capacity in human seminal plasma

Evaluation of Total Antioxidant Capacity in Serum and Follicular Fluid of Women Undergoing ICSI and its Association with Implantation Failure

Purpose: Total antioxidant capacity (TAC) in women serum and follicular fluid (FF) which surroundingoocytes may be related to the implantation failure .Therefore, we herein examined the relationship betweentotal antioxidant capacity status in serum and FFand it is association with implantation failureMethod: One hundred and seventeen of non-reproductive women who underwent intra-cytoplasmic sperminjection (ICSI)included in this study and conducted between March 2018 and April 2019 in Kamal ALSamaraiHospital, center of fertility and IVF. Serum and follicular fluid were collected from non-reproductivewomen aged ranged 20-45 years and BMI (ranged 21.9-36.3kg/m2), TAC were measured using sandwichELISA in serum and follicular fluid specimen of 21 women of successful implantation compared to 96experienced implantation failures.Results: TAC was increased in serum of implantation failure compared to successful but not significantdifferences between two study groups. Whereas TAC levels were highly significant (P=0.002) inFFof women who had successful implantation (1.08 ± 0.64mmol/L) whereas in failure were lower(0.55 ±0.42 mmol/L). In addition to that, when evaluating the frequency of TAC category in FF revealed highlysignificant differences (P=0.003) between two groups, the majority of failure groups(84.4%) had low TACcompared with (40%) in successful groups, while a significant increase of sufficient TAC in successful thanfailure groups (50% versus 6.1% respectively), whereas the borderline TAC were (9.1% versus 10%) infailure and successful groups.Conclusions: TAC in FF may be potential markers for implantation successful in ICSI cycle.

All‐trans retinoic acid improves pancreatic cell proliferation on induced type 1 diabetic rats

All-trans retinoic acid (ATRA) has been extensively studied as an integrating component of endocrine functions in the pancreas. The aim of this study was to evaluate the effects of ATRA on physiopathological biomarkers in an experimental model of rat with type 1 diabetes induced by alloxan (T1D). Twenty Wistar rats were divided equally into five groups, each receiving a different treatment: a control group (CG), a diabetic group without T1D treatment, a diabetic group treated with ATRA, a diabetic group supplemented with vitamin E (VIT E), and a group that was given olive oil (V). The administration of ATRA for 17days produced a significant reduction in weight and glucose levels, compared to the T1D and VIT E groups. The evaluation of total antioxidant capacity (TAC) and lipoperoxidation showed no relevant difference among the groups. The results of the histological analysis showed similarities both in the size and in the number of islets of Langerhans in the pancreatic tissue obtained from the ATRA group and the CG. ATRA displayed a significant reduction of glycemic values in diabetic rats. Ultrastructurally, ß-cells, acinar, and ductal cells restored their normal appearance. ATRA can contribute to the recovery of pancreatic damage due to alloxan induction. It seems that the antioxidant effect of ATRA is not responsible for the differences observed.

Evaluation of Total Antioxidant Capacity and Total Oxidant Status of Preterm and Term Breast Milk during the Course of Lactation and within a Nursing Session

Breast milk (BM) contains antioxidant molecules which may offer protection against oxidative stress (OS). We aim to investigate oxidant-antioxidant balance in preterm BM during the course of lactation and within a nursing session. Total antioxidant capacity (TAC) and total oxidant status (TOS) were measured in colostrum, transitional, and mature BM samples of preterm infants born earlier than 34th week of pregnancy and healthy term infants. Oxidative stress index (OSI) was calculated. Foremilk and hindmilk samples were collected separately. In colostrum and transitional milk, TAC (p < 0.001 and p = 0.001, respectively) and TOS (p = 0.005 and p < 0.001, respectively) were lower in preterm BM compared with term BM. OSI was also lower in preterm BM, but it was statistically significant only in transitional milk (p < 0.001). TAC was highest in colostrum and decreased through the course of lactation. However, the decrease in TAC was not statistically significant in preterm BM. Lowest values of TOS and OSI were observed in colostrum. In transitional term BM, hindmilk had a better oxidant-antioxidant profile as indicated by lower TOS and OSI. Oxidant-antioxidant balance is preserved in BM in every stage of lactation. Preterm BM has lower OSI which may offer benefits to preterm newborn against OS.

A comparative evaluation of total antioxidant capacity of saliva in children with and without Gingivitis

Gingivitis is a reversible and non-destructive form of periodontal disease. Oxidative stress contributes in the pathogenesis of periodontal diseases5. The oxidative stress has been implicated as one of the important contributory etiologic factors in many of the oral inflammatory pathologies including gingivitis. This research analyzed the Total antioxidant (TAC) of biological fluids including saliva. The present cross-sectional study was conducted to evaluate the total antioxidant capacity (TAC) of saliva in children with/ without gingivitis and its relation with Age and Gender. For measuring the TAC of saliva: Cayman's Antioxidant Assay Kit was used and Gingival Index Measured through The Gingival Index (Loe and Silness, 1963). The results were analyzed using descriptive statistics and making comparisons between cases and control by using SPSS software version 20. In this result, mean TAC of saliva in case children group was found lower 0.203 ± 0.053 compared to control children group was higher 0.236 ± 0.048. While, in male and female children of aged 3-5 years were found antioxidant activity (TAC) lower in compared to control groups. But among males aged 6-13 years it was found that the mean antioxidant capacity of saliva in case group was 0.259 ± 0.040 while in control group it was 0.295 ± 0.026. The TAC of saliva in males was found high compared to female. A weak negative correlation was found between the TAC and gingival index. In conclusion TAC decreases in children with gingivitis compared to healthy children. The gingivitis was more observed in female leading to lower TAC value

Evaluation of total antioxidant capacity before &amp; after administration of iron therapy in iron deficient pregnant women

Evaluation of total antioxidant capacity before &amp; after administration of iron therapy in iron deficient pregnant women

Nitroxide-enhanced magnetic resonance imaging of kidney dysfunction in vivo based on redox-imbalance and oxidative stress.

This study reports a non-invasive magnetic resonance imaging (MRI) of kidney dysfunction in mice, based on the induction of redox-imbalance and oxidative stress in the renal tissues, using mito-TEMPO as redox-sensitive contrast probe. Kidney dysfunction was triggered by hypercholesterolemia. The mice were divided in three groups: (i) on normal diet (ND); (ii) on cholesterol diet (CD); (iii) on cholesterol plus cholestyramine diet (CC). After 15 weeks feeding, the mice were subjected to the following analyses: plasma cholesterol levels; serum test for renal functionality; nitroxide-enhanced MRI of tissue redox-status in vivo; histochemical staining of tissue section to visualize renal damage; evaluation of total antioxidant capacity and oxidative stress on isolated tissue specimens. MRI signal of mito-TEMPO in the kidney was characterized by: high intensity and long life-time in CD mice, indicating a high oxidative capacity of renal tissues; poor intensity and short life-time in ND mice, indicating a high reducing capacity; moderate intensity and relatively short life-time in CC mice, indicating a protective effect of lipid-lowering drug. The data were confirmed on isolated tissue specimens, using conventional tests. They suggest that hypercholesterolemia induces redox-imbalance in kidney and this process could be visualized using MRI and mito-TEMPO as a redox-sensitive contrast.

Effect of Short-Term Swim Exercise on Cardiac Dysfunction Induced by Doxorubicin in Rats

AbstractBackground: Long-term exercise could confer protection against Doxorubicin-induced cardiotoxicity, yet, the effect of short-term exercise just prior to exposure to Doxorubicin (Dox) is still unclear.Aim: To investigate the effect of short-term exercise on cardiac dysfunction induced by Dox treatment.Material and Methods: Sixty nine female albino rats were assigned into 4 groups: Group 1: Control (sedentary rats, n=17), Group 2: Dox (rats received single intraperitoneal injection of Dox in a dose of 20mg/kg, n=18), Group 3: Exc, (n=16), Group 4: Exc +Dox (n=18). Rats were subjected to recording of the ECG, measurement of arterial blood pressure, echocardiograghy, analysis of serum parameters of SGOT, LDH, CPK-MB, troponin I (cTnI) and evaluation of total antioxidant capacity, Malondialdehyde (MDA) and heat shock protein (Hsp20) in the cardiac tissue.Results: Compared to the control, Dox-treated rats showed significant prolongation of QT interval, with insignificant depression of the R voltage and the elevation of systolic (SBP), diastolic (DBP), mean (MAP) blood pressures were statistically insignificant. These changes were accompanied by significant elevation of serum SGOT and cardiac tissue MDA and Hsp20. Also, compared to the control, rats exposed to 3 days exercise just before Dox injection (Exc + Dox) showed significant prolongation of QT even more than in Dox group. However, the depression of the R voltage and the elevation of the SBP, DBP, and MAP become statistically significant compared to the control. These changes were associated with significant increase in SGOT. However, compared to Dox group, the Exc+Dox demonstrated significant prolongation in QT, significant reduction in the ejection fraction with significant reductions in MDA and Hsp20.Conclusion: Short-term swim exercise training just prior to doxorubicin exposure is risky and makes the heart more predisposed to arrhythmia despite of the relative improvement in cardiac oxidative status.

L-ascorbic acid and α-tocopherol attenuate arsenic trioxide-induced toxicity in H9c2 cardiomyocytes by the activation of Nrf2 and Bcl2 transcription factors

Arsenic trioxide (As2O3) is a potent drug for the treatment of acute promyelocytic leukemia (APL) and has achieved remarkable remissions in patients. Unfortunately, clinical reports have shown that the treatment is associated with cardiotoxicity. Many efforts have been made to mitigate drug-mediated cardiac damage using naturally occurring antioxidant compounds possessing free radical scavenging activity. The present investigation aims to explore protective role of L-ascorbic acid (L-AA) and α-tocopherol (α-TOC) from As2O3-induced oxidative stress in H9c2 cardiomyocytes through the evaluation of Nrf2 (nuclear factor erythroid 2-related factor 2) and Bcl-2 (B-cell lymphoma 2) transcription factors. The in vitro study was conducted using H9c2 cardiomyocytes. The evaluation of total antioxidant capacity, mitochondrial membrane potential, cellular calcium concentration and reactive oxygen species generation was performed. Oxidative stress (Nrf2) and anti-apoptotic (Bcl2) signaling indicators were measured by reverse transcriptase polymerase chain reaction. A depletion of the total antioxidant capacity and mitochondrial transmembrane potential were observed in As2O3-treated cardiomyocytes. In addition, the cellular calcium concentration and ROS generation were found to be increased on treatment with As2O3 with the alterations in the activity of transcription factors, Nrf2 and Bcl2. Co-treatment of antioxidant vitamins with As2O3 resulted in a significant reversal of oxidative stress and alteration on the antioxidant defense through the activation of Nrf2 and Bcl2. L-AA and α-TOC alleviates As2O3-induced oxidative stress in cardiac cells by activating Nrf2 and Bcl2 transcription factors that results in increased cell survival and prevents apoptosis.

Evaluation of Total Antioxidant Capacity (TAC) of Saliva in Caries Active and Caries free Tribal School Going Children of Wardha District.

Evaluation of Total Antioxidant Capacity (TAC) of Saliva in Caries Active and Caries free Tribal School Going Children of Wardha District.