Mixture Of Α-tocopherol Research Articles

Comparative screening of organic solvents, ionic liquids, and their binary mixtures for vitamin E extraction from deodorizer distillate

Although it is well known that solvent is one of the most important decision variables in liquid-liquid extraction processes, many previous studies focused on a specific class of solvents while neglecting alternatives. This work presents a comparative screening of two types of most extensively studied solvents, i.e., organic solvents (OS) and ionic liquids (ILs), as well as their binary systems for the extraction of vitamin E from methylated oil deodorizer distillates (modelled as a mixture of α-tocopherol and methyllinoleate). For this practically relevant task, the ternary liquid-liquid equilibria (LLE) of {OS or IL + α-tocopherol + methyllinoleate} are first calculated by use of the COnductor-like Screening Model for Real Solvents (COSMO-RS), after which the physical and environmental, health, and safety (EHS) properties of solvents are assessed to identify the top-ranked OS and ILs. To intensify the separation performance, binary solvent systems are also explored, where one of the pre-selected ILs is taken as the first solvent for α-tocopherol and an OS is screened as the second solvent for methyllinoleate. Then, the IL-OS combinations are investigated regarding their binary immiscibility and ranked with respect to the LLE performance in the quaternary system {IL + α-tocopherol + methyllinoleate + OS}. By comparing the extraction distribution coefficient and the selectivity of the top-ranked OS, ILs and IL-OS systems, the notable intensified performance of binary solvent system is proven.

Efecto de la inclusión de carne cruda en un paté cocido de carne mecánicamente recuperada de trucha arcoíris

The fishing industry generates large quantities of by-products, most of which are not used and are therefore discarded. The objective of the present research was the elaboration of a pâté-type sausage from mechanically recovered meat of rainbow trout (Oncorhynchus mykiss). The meat was obtained from trout skelons, which were passed through a grinder and sprayed with a mixture of α-tocopherol (0.02%) and ascorbic acid (0.05%). The formulation of the pate was as follows: mechanically recovered trout meat (74.4%), salt (1.3%), sodium tripolyphosphate (0.8%), starch (2%), soy protein isolate (2.4%), margarine (16.7%), soy lecithin (1.9%), onion powder (0.2%), garlic powder (0.2%) and pepper powder (0.1%). Three formulations were prepared: PCR1 (80% cooked meat and 20% raw meat), PCR2 (90% cooked meat and 10% raw meat) and PCR3 (100% cooked meat). For each formulation, the following were evaluated: texture profile, color and sensory evaluation, the latter with the participation of 30 untrained panelists using a 9-point hedonic scale, in which each formulation obtained an average of 6 ("I like it moderately"). The best formulation was PCR3, whose proximate composition was determined: 64% moisture, 16% fat, 12.5% protein, and 3.5% ash. The pâté of mechanically recovered trout meat proved to have a high nutritional value and a good level of sensory acceptance, demonstrating that it is a good alternative for the use of trout fillet by-products.

Antioxidants enhance the recovery of three cycles of bleomycin, etoposide, and cisplatin–induced testicular dysfunction, pituitary-testicular axis, and fertility in rats

To investigate the effects of an antioxidant cocktail (AC) on bleomycin, etoposide, and cisplatin (BEP)-induced testicular dysfunction. In vivo study. Research laboratory. Adult male and female Sprague-Dawley rats. The rats were treated with three cycles of 21 days each of therapeutically relevant dose levels of BEP (0.75, 7.5, and 1.5 mg/kg) with or without the AC (a mixture of α-tocopherol, L-ascorbic acid, Zn, and Se). Sperm parameters, fertility, serum hormone levels (ELISA), testicular histopathology, and expression of proliferating cell nuclear antigen (PCNA), and transferrin (Western blotting and immunohistochemistry) were evaluated at the end of treatment and a 63-day recovery period. At the end of treatment, the AC improved BEP-induced decrease in sperm motility and increase in abnormality but had no effect on reduced sperm count, fertility, and tubular atrophy, although it up-regulated germ cell proliferation. The AC normalized reduced inhibin B levels, but had no effect on decreased transferrin and testosterone and elevated LH levels. At the end of the recovery period, the AC enhanced the expression of PCNA and transferrin, repopulation of germ cells, LH-testosterone axis, and fertility, but had no effect on reduced FSH and elevated inhibin B levels. The antioxidants protect and then enhance the recovery of testicular and reproductive endocrine functions when administered concomitantly with BEP therapy. The AC may be beneficial to regain testicular functions after chemotherapy.

Oxidative reactivity of unsaturated fatty acids from sunflower, high oleic sunflower and rapeseed oils subjected to heat treatment, under controlled conditions

The oxidation kinetics of three vegetable oils (sunflower, high oleic sunflower and rapeseed) were followed during heat treatment (100 °C, 120 °C and 150 °C for 6 h), in the absence or presence of α-tocopherol (around 15 × 10−4 molL−1) or a mixture of α-tocopherol and chlorogenic acid (around 15 × 10−4 molL−1 of each). The kinetics were followed by measuring several chemical markers: fatty acids, conjugated dienes, hydroperoxides and aldehydes. The results showed that the unsaturation degree of the oils tested was the predominant parameter influencing the progress of oxidation kinetics. In this sense, sunflower oil was systematically more oxidized than rapeseed oil, which itself was more oxidized than high oleic sunflower oil.Oxygenation conditions and oil temperature were also determinant inducers of oxidation. The addition of α-tocopherol significantly delayed the formation of oxidation products while chlorogenic acid did not enhance the oxidative stability of oils but protected α-tocopherol during heating.

α-Tocopherol impact on oxy-radical induced free radical decomposition of DMSO: Spin trapping EPR and theoretical studies

EPR spin trapping and theoretical methods such as density functional theory (DFT) as well as combined DFT and quadratic configuration interaction approach (DFT/QCISD) were used to identify the radicals produced in the reaction of oxy-radicals and dimethyl sulfoxide (DMSO) in the presence and absence of α-tocopherol. Additionally, the mixtures of α-tocopherol with linolenic acid and glyceryl trilinoleate as well as bioglycerols (glycerol fractions from biodiesel production) were tested. α-Tocopherol inhibited oxidation of the main decomposition product of DMSO, •CH 3 to •OCH 3 but did not prevent the transformation process of N-t-butyl- α-phenylnitrone (PBN) into 2-methyl-2-nitrosopropane (MNP). Theoretical investigations confirmed the structures of proposed spin adducts and allowed to correlate the EPR parameters observed in the experiment with the spin adducts electronic structure.

Suppressive Effect of .ALPHA.-Tocopherol Complexed with .BETA.-Cyclodextrin on the Oxidation of Methyl Linoleate

α-Tocopherol complexed with β-cyclodextrin was prepared, and its suppressive effect on the oxidation of methyl linoleate was kinetically examined using the Weibull model. The rate constant, k, of the Weibull equation, for α-tocopherol oxidation of methyl linoleate was nearly equal to that observed with a mixture of α-tocopherol and β-cyclodextrin. Doubling the amount of α-tocopherol further reduced the k value, but the extent of the reduction was not large. All k values with the inclusion complex were lower than those without it. As the amount of free α-tocopherol only slightly affected the suppressive activity, the inclusion complexing of α-tocopherol with β-cyclodextrin contributes to lowering the k value. The suppressive effect of α-tocopherol complexed with β-cyclodextrin on methyl linoleate oxidation is due to the protection of α-tocopherol by its inclusion in β-cyclodextrin and the gradual release of α-tocopherol from the inclusion complex to the lipid phase.

Liposomal antioxidants in combating ischemia-reperfusion injury in rat brain

Liposome-encapsulated antioxidants have been tested in vivo to prevent oxidative attack during cerebral ischemia and reperfusion. Oxidative stress is a causal factor in the neuropathogenesis of ischemic-reperfusion injury. From the therapeutic point of view free chemical antioxidants were almost ineffective to protect cerebral tissues from those oxidative attacks. Thus an attempt has been made to prevent the oxidative damage due to the cerebral ischemic insult by the introduction of chemical antioxidants, ascorbic acid and α-tocopherol either encapsulated or intercalated in small unilamellar liposomes. The effectiveness of antioxidant-loaded liposomes was tested against an experimental in vivo rat model of global cerebral ischemia. Oxidative free radical attack on cerebral tissues by the ischemic insult and brief reperfusion was accounted for by the amount of diene production per unit of tissue protein. Diene production in ischemic reperfused rat brain increases almost twofold over that of the normal rats. Prevention of excess diene production has been attributed to rats when they were treated either with L-ascorbic acid-encapsulated liposomes or α-tocopherol intercalated liposomes 2 hours prior to the cerebral ischemic insult. Complete restriction of excess diene generation has also been achieved when a mixture of α-tocopherol and L-ascorbic acid-encapsulated liposomes were injected 3 hours before the ischemic infraction.

Synergistic Antioxidant Effects of Rosemary and α-Tocopherol at Different Storage Temperatures and Its Application for Inhibiting Dried Sardine Meat Oxidation

A mixture of α-tocopherol and rosemary extract, as additives each at 0.035 % (total 0.07 %), expressed very strong antioxidant activity in sardine oil stored at 30°C, 50°C and dried sardine meat at 5°C. In sardine oil, their combination not only inhibited the formation of hydroperoxides much more effectively than when present separately but the activity of tocopherol was retained for a longer period. In dried sardine meat, combined application caused the lowest PV, and (EPA + DHA)/16:0 was higher. There was also lesser decomposition of triacylglycerol due to oxidation

Enhancing the antioxidant effect of α-tocopherol with rosemary in inhibiting catalyzed oxidation caused by Fe 2+ and hemoprotein

A mixture of α-tocopherol and rosemary extract (0·035% + 0·035%) was used to inhibit fish lipid oxidation catalyzed by Fe 2+ or hemoprotein. In a sardine oil model system, a mixture of α-tocopherol and rosemary extract showed a significantly stronger antioxidant effect, as it prolonged the induction period for 10 and 16 days longer than α-tocopherol alone and rosemary extract alone, respectively. In addition, the effective lifetime of α-tocopherol in samples treated with the α-tocopherol and rosemary extract mixture was 10 days longer than in samples with only α-tocopherol added even though the amount of added α-tocopherol in the latter case was twice that for the mixture. In fish dark muscle, the mixture of α-tocopherol and rosemary extract also showed a stronger anti-oxidant effect than either tocopherol or rosemary extract alone. Treatment of samples with this mixture also led to a lower rate of decomposition of highly unsaturated fatty acids, myoglobin and hemoglobin, and triglyceride compared to samples treated with tocopherol or rosemary extract alone.