scholarly journals Relationship between tocopherols depletion and polymerised triacylglycerols formation during heating of vegetable oils

2019 ◽  
Vol 36 (No. 6) ◽  
pp. 441-451
Author(s):  
Jakub Fišnar ◽  
Monika Sabolová ◽  
Zuzana Réblová
Keyword(s):  
Soybean Oil ◽  
Antioxidant Capacity ◽  
Vegetable Oils ◽  
Palm Oil ◽  
Total Antioxidant Capacity ◽  
Alpha Tocopherol ◽  
Degree Of Unsaturation ◽  
Total Antioxidant ◽  
Typical Temperature

Alpha tocopherol and total tocopherols depletion in relation to polymerised triacylglycerols formation were studied during the heating of nine vegetable oils (olive, palm, peanut, sunflower, rapeseed, soybean, grapeseed, maize and rice) at oil temperature 180°C (as a typical temperature during frying practise). It was observed that the rate of tocopherols depletion (expressed as the function of polymerised triacylglycerols content) decreased with the increasing degree of unsaturation and total antioxidant capacity of the tested oils (P < 0.05). Consequently, no tocopherols were present in olive, peanut and palm oil at their half lifespan (i.e., at 6% of polymerised triacylglycerols), whereas tocopherols in maize, sunflower, grapeseed, rice and, particularly, soybean oil were present even at the end of their lifespan, (i.e., at 12% polymerised triacylglycerols). These findings have not been published yet, or only little published.

Estimate of antioxidant capacity and lipid peroxidation in plasma of healthy subjects

Open Medicine ◽  
2006 ◽  
Vol 1 (1) ◽  
pp. 23-34
Author(s):  
Anna Gorąca ◽  
Beata Skibska
Keyword(s):  
Ascorbic Acid ◽  
Uric Acid ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Plasma Concentrations ◽  
Beta Carotene ◽  
Alpha Tocopherol ◽  
Elderly Subjects ◽  
Total Antioxidant

AbstractSerum contains various antioxidant molecules that may provide important protection against free radical attack. The aim of this work was to assess the total antioxidant capacity of plasma and a marker of lipid per oxidation [(thiobarbituric acid-reactive substances (TBARS)] in plasma of healthy smoking and non-smoking young and elderly subjects. In addition, we investigated plasma concentrations of α-tocopherol, β-carotene, and ascorbic acid. In in vitro experiments, the effects of exogenous compounds (ascorbic acid, uric acid, Trolox) on total ferric-reducing activity of plasma (FRAP) were also tested. We demonstrated that total antioxidant capacity of plasma obtained from healthy non-smoking young subjects was significantly higher than plasma antioxidant capacity of smoking elderly subjects. The concentration of TBARS in young non-smoking volunteers was lower than that in young smokers. The concentration of TBARS in elderly non-smoking volunteers was lower than in elderly smokers. Plasma concentrations of alpha-tocopherol, beta-carotene and ascorbic acid were significantly lower in elderly smoker than in elderly non-smokers of the same age. No difference in the plasma levels of alpha-tocopherol, beta-carotene and ascorbic acid were found in 22-year-old smoking and non-smoking subjects. In vitro addition of ascorbic acid, uric acid, or Trolox to plasma samples significantly increased their total antioxidant capacity. Decrease of FRAP values and increase of TBARS concentrations is a significant physiologic condition of the aging process. Supplementation of antioxidants could be useful for the enhancement of antioxidant screen in plasma.

Trans-resveratrol supplement lowers lipid peroxidation responses of exercise in male Wistar rats

2020 ◽  
pp. 1-6 ◽  
Author(s):  
Masoud Nasiri ◽  
Saja Ahmadizad ◽  
Mehdi Hedayati ◽  
Tayebe Zarekar ◽  
Mehdi Seydyousefi ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Wistar Rats ◽  
Enzymatic Antioxidants ◽  
Acute Response ◽  
Total Antioxidant ◽  
Male Wistar Rats ◽  
Exercise Induced ◽  
And Control

Abstract. Physical exercise increases free radicals production; antioxidant supplementation may improve the muscle fiber’s ability to scavenge ROS and protect muscles against exercise-induced oxidative damage. This study was designed to examine the effects of all-trans resveratrol supplementation as an antioxidant to mediate anti-oxidation and lipid per-oxidation responses to exercise in male Wistar rats. Sixty-four male Wistar rats were randomly divided into four equal number (n = 16) including training + supplement (TS), training (T), supplement (S) and control (C) group. The rats in TS and S groups received a dose of 10 mg/kg resveratrol per day via gavage. The training groups ran on a rodent treadmill 5 times per week at the speed of 10 m/min for 10 min; the speed gradually increased to 30 m/min for 60 minutes at the end of 12th week. The acute phase of exercise protocol included a speed of 25 m/min set to an inclination of 10° to the exhaustion point. Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activity, non-enzymatic antioxidants bilirubin, uric acid, lipid peroxidation levels (MDA) and the total antioxidant capacity (TAC) were measured after the exercise termination. The data were analyzed by using one-way ANOVA. The result showed that endurance training caused a significant increase in MDA level [4.5 ± 0.75 (C group) vs. 5.9 ± 0.41 nmol/l (T group)] whereas it decreased the total antioxidant capacity [8.5 ± 1.35 (C group) vs. 7.1 ± 0.55 mmol/l (T group)] (p = 0.001). In addition, GPx and CAT decreased but not significantly (p > 0.05). The training and t-resveratrol supplementation had no significant effect on the acute response of all variables except MDA [4.3 ± 1.4 (C group) vs. 4.0 ± 0.90 nmol/l (TS group)] (p = 0.001) and TAC [8.5 ± 0.90 (C group) vs. 6.6 ± 0.80 mmol/l (TS group)] (p = 0.004). It was concluded that resveratrol supplementation may prevent exercise-induced oxidative stress by preventing lipid peroxidation.

Summer Day/Night Gender Differences in Serum Total Antioxidant Capacity as a Methodological Pitfall in Human Antioxidant Research

2016 ◽  
Vol 4 (2) ◽  
Author(s):  
Armando L. Morera-Fumero ◽  
Pedro Abreu-Gonzalez ◽  
Lourdes Fernandez- Lopez ◽  
Estefanía Díaz-Mesa ◽  
Maria del Rosario Cejas-Mendez
Keyword(s):  
Gender Differences ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Total Antioxidant

EXTRACTION OPTIMIZATION AND ANTIOXIDANT ACTIVITY OF PHENOLIC COMPOUNDS FROM AVOCADO PEEL

2019 ◽  
pp. 49-59
Author(s):  
Nu Linh Giang Ton ◽  
Thi Hoai Nguyen ◽  
Quoc Hung Vo
Keyword(s):  
Antioxidant Activity ◽  
Response Surface Methodology ◽  
Antioxidant Capacity ◽  
Response Surface ◽  
Total Antioxidant Capacity ◽  
Total Phenolic Content ◽  
Phenolic Content ◽  
Quadratic Model ◽  
Total Phenolic ◽  
Total Antioxidant

Avocado peel has been considered as a potential source of natural antioxidants in which phenolics are among the most important compounds. Therefore, this study aims to optimize the extraction process of phenolics using response surface methodology and evaluate the corresponding antioxidant activity. From the quadratic model, the optimal condition was determined including the ethanol concentration 54.55% (v/v), the solvent/solute ratio 71.82/1 (mL/g), temperature 53.03 oC and extraction time 99.09 min. The total phenolic content and the total antioxidant capacity at this condition with minor modifications were 26,74 ± 0,04 (mg GAE/g DW) and 188.06 ± 1.41 (mg AAE/g DW), respectively. The significant correlation between total phenolic content and total antioxidant capacity was also confirmed. Key words: response surface methodology, central composite rotatable design, total phenolic content, total antioxidant capacity, avocado peel

Evaluation of Salivary Antioxidants and Oxidative Stress Markers in Male Smokers

2019 ◽  
Vol 22 (7) ◽  
pp. 496-501
Author(s):  
Fatemeh Ahmadi-Motamayel ◽  
Parisa Falsafi ◽  
Hamidreza Abolsamadi ◽  
Mohammad T. Goodarzi ◽  
Jalal Poorolajal
Keyword(s):  
Oxidative Stress ◽  
Uric Acid ◽  
Free Radicals ◽  
Antioxidant Capacity ◽  
Cigarette Smoke ◽  
Total Antioxidant Capacity ◽  
The Body ◽  
Total Antioxidant ◽  
The Mean ◽  
And Oxidative Stress

Background: Cigarette smoke free radicals can cause cellular damage and different diseases. All the body fluids have antioxidants which protect against free radicals. Objective: The aim of this study was to evaluate salivary total antioxidant capacity and peroxidase, uric acid and malondialdehyde levels in smokers and a nonsmoking control group. Methods: Unstimulated saliva was collected from 510 males. A total of 259 subjects were current smokers and 251 were non-smokers. The levels of salivary total antioxidant capacity, uric acid, peroxidase and malondialdehyde were measured using standard procedures. Data were analyzed with t test and ANOVA. Results: The smokers were younger and dental hygiene index was higher than healthy nonsmoking controls. The mean total antioxidant capacity in smokers and nonsmokers was 0.13±0.07 and 0.21±011, respectively (P=0.001). Smokers had significantly lower peroxidase and uric acid levels than healthy controls. In addition, the mean malondialdehyde levels in the smokers and nonsmokers were 4.55 ±2.61 and 2.79 ±2.21, respectively (P=0.001). Conclusion: Cigarette smoke produces free radical and oxidative stress, causing many side effects. Salivary antioxidant levels decreased and malondialdehyde levels increased in smokers, indicating the high oxidative stress among smokers compared to nonsmokers. Cigarette smoke had deleterious effects on main salivary antioxidants levels.

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