Inhibition Of Thiobarbituric Acid Reactive Substances Research Articles

Stabilization of rose hip oil with pomegranate peel extract during accelerated storage

Rose hip seed oil is a rich source of polyunsaturated fatty acids, as well as tocopherols, carotenoids, sterols, phospholipids, and phenolic compounds. On the other hand, due to the high content of polyunsaturated fatty acids, this oil is prone to oxidation. The aim of this study was to investigate the influence of a natural antioxidant, i.e., pomegranate peel extract, and its combination with butylated hydroxytoluene as a commonly used synthetic antioxidant, on the stability of rose hip oil. The stability of samples without and with different antioxidants was monitored through analysis of the fatty acid composition and measurement of the quality and stability parameters of the oil (peroxide value, p-anisidine value, thiobarbituric acid reactive substances inhibition, total phenolic content and antiradical activity) during a storage period of 12 days at 65 ?C. Pomegranate peel extract (0.1 %) inhibited more effectively the second stage of oxidation than butylated hydroxytoluene (0.02 %), while the first stage of oxidation was better prevented by the synthetic antioxidant. Furthermore, the addition of pomegranate peel extract increased the total phenolic content of the rose hip oil as well as its antiradical activity. Thus, pomegranate peel extract could be used as a potent natural antioxidant for the stabilization of beneficial but unstable rose hip oil.

Antioxidant and anti-inflammatory properties of selected polyherbal preparations: Oroki herbal, Swedish bitters and Yoyo bitters

Objective: Polyherbal preparations are extracts obtained from different medicinal plants. These herbal preparations are orally administered as therapy against numerous oxidative stress and inflammation mediated diseases. This study was designed to evaluate the antioxidant and anti-inflammatory properties of Oroki herbal, Swedish bitters and Yoyo bitters using in vitro models. Methods: Antioxidant studies were carried out using total antioxidant capacity (TAC), thiobarbituric acid reactive substances (TBARS), ferric reducing antioxidant power (FRAP) and 1’1’-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assays while anti-inflammatory studies were performed using human red blood cell (HRBC) membrane stabilization and anti-denaturation of bovine serum albumin (BSA) assays. Results: Data showed that Oroki herbal had the highest TAC, inhibition of TBARS, FRAP absorbance range, DPPH scavenging activity while Swedish bitters had the highest stabilization of hypotonicity-induced hemolysis of HRBC and inhibition of heat-induced BSA denaturation when compared with other herbal preparations. Conclusion: Findings from this study indicated that Oroki herbal exhibited the highest antioxidant activity while Swedish bitters had the highest anti-inflammatory property in vitro. Furthermore, the medicinal properties of these polyherbal preparations could be attributed to their antioxidant and anti-inflammatory activities that could mitigate against oxidative stress and inflammation mediated diseases.

Cytoprotective effect of palm kernel cake phenolics against aflatoxin B1-induced cell damage and its underlying mechanism of action.

BackgroundPalm kernel cake (PKC), a by-product of the palm oil industry is abundantly available in many tropical and subtropical countries. The product is known to contain high levels of phenolic compounds that may impede the deleterious effects of fungal mycotoxins. This study focused on the evaluation of PKC phenolics as a potential cytoprotective agent towards aflatoxin B1 (AFB1)-induced cell damage.MethodsThe phenolic compounds of PKC were obtained by solvent extraction and the product rich in phenolic compounds was labeled as phenolic-enriched fraction (PEF). This fraction was evaluated for its phenolic compounds composition. The antioxidant activity of PEF was determined by using 1,1-diphenyl-2-picryl-hydrazil scavenging activity, ferric reducing antioxidant power, inhibition of ß-carotene bleaching, and thiobarbituric acid reactive substances assays. The cytotoxicity assay and molecular biomarkers analyses were performed to evaluate the cytoprotective effects of PEF towards aflatoxin B1 (AFB1)-induced cell damage.ResultsThe results showed that PEF contained gallic acid, pyrogallol, vanillic acid, caffeic acid, syringic acid, epicatechin, catechin and ferulic acid. The PEF exhibited free radical scavenging activity, ferric reducing antioxidant power, ß-carotene bleaching inhibition and thiobarbituric acid reactive substances inhibition. The PEF demonstrated cytoprotective effects in AFB1-treated chicken hepatocytes by reducing the cellular lipid peroxidation and enhancing antioxidant enzymes production. The viability of AFB1-treated hepatocytes was improved by PEF through up-regulation of oxidative stress tolerance genes and down-regulation of pro-inflammatory and apoptosis associated genes.ConclusionsThe present findings supported the proposition that the phenolic compounds present in PKC could be a potential cytoprotective agent towards AFB1 cytotoxicity.

Phenolic profile and antioxidant properties of commercial and wild Fragaria vesca L. roots: A comparison between hydromethanolic and aqueous extracts

The phenolic profile of hydromethanolic extracts, infusions and decoctions of commercial and wild samples of Fragaria vesca (wild strawberry) roots was obtained by HPLC-DAD/ESI-MS, and further correlated with their antioxidant properties. Commercial and wild samples showed similarities in terms of flavan-3-ols (TF3O), with catechin derivatives, mainly procyanidins, as major compounds in both samples. The commercial sample presented ellagic acid glycosides, whereas the wild sample presented flavonols (TF) and dihydroflavonols (TdhF, taxifolin derivatives). The infusion of wild sample gave the highest content of total phenolic compounds (TPC), DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity, reducing power and TBARS (thiobarbituric acid reactive substances) inhibition. The antioxidant capacity (mainly β-carotene bleaching and TBARS inhibition) observed for the wild sample is correlated with TF3O, TF and TPC. Overall, the high antioxidant potential of F. vesca roots was demonstrated and could be achieved directly by consumption of infusions/decoctions or by incorporating hydromethanolic extracts in antioxidant formulations.

Effect of Soy Protein Isolate Coating on Meat Quality of Pork Fresh Cut during Refrigerated Storage

Soy protein isolate (SPI)-based edible coating, with and without carboxymethyl cellulose (CMC), were used to reduce oxidative degradation of cut pork stored at <TEX>$4^{\circ}C$</TEX> for 5 days. The SPI coating reduced (p<0.05) thiobarbituric acid-reactive substances (TBARS) and peroxide value (PV), compared with controls. The inhibition of TBARS and PV for SPI-coated porks with and without CMC, compared with the control was 19.1 and 23.9, and 25.7 and 37.7%, respectively. The SPI coating prevented loss of <TEX>$L^*$</TEX> and <TEX>$a^*$</TEX> values of porks compared to the control. The ability of the SPI coating to provide a moisture barrier for the porks was reduced (p<0.05). The SPI-coated porks with and without CMC reduced moisture loss by 37.3 and 44.6%, respectively, over the control. However, SPI coating of porks did not inhibit the growth of either total plate counts or L. monocytogenes. The result revealed that SPI can effectively be used as a natural antioxidative coating to extend quality and shelf life of pork.

Comparison of solvent and microwave extracts of cranberry press cake on the inhibition of lipid oxidation in mechanically separated turkey

Cranberry press cake, an under utilized by-product of the cranberry processing industry is a potential source of food antioxidants. The objective of this research were (1) to prepare extracts from cranberry press cake using solvent extraction (SE) and microwave assisted solvent extraction (MASE), and (2) to test the ability of these extracts to inhibit lipid oxidation in mechanically separated turkey (MST). Water, ethanol and acetone were used as extraction solvents. Heating press cake prior to extraction with 70% ethanol increased antioxidant efficacy compared to extracting unheated press cake. Water extracts were least effective in inhibiting lipid oxidation. The most effective extracts were obtained by SE with 100% acetone or MASE with 100% ethanol. A poor correlation of 0.69 was obtained between the total phenols in the extracts and their ability to inhibit thiobarbituric acid reactive substances (TBARS) formation in MST. The correlation coefficient between the amount of quercetin in the extracts and the number of days of TBARS inhibition in MST was 0.87. This indicates that although quercetin may be good inhibitor of lipid oxidation, polyphenols other than quercetin are likely have a role in the inhibition of TBARS in MST. For a similar yield of the extracts, MASE extract using 100% ethanol was a better inhibitor than 100% ethanol SE extract of lipid oxidation in MST. In terms of choice of solvent, based on their flammability and toxicity, MASE with 100% ethanol would be a more likely a choice over SE with 100% acetone, for inhibiting oxidation in MST.

Antrodia Camphoratain Submerged Culture Protects Low Density Lipoproteins Against Oxidative Modification

Antrodia camphorata is well known in Taiwan as a traditional Chinese medicine. In this study, we have investigated the antioxidant properties of a fermented culture broth of Antrodia camphorata (FCBA) and the aqueous extracts of mycelia from Antrodia camphorata (AEMA) on the oxidative modification of human low-density lipoproteins (LDL), as induced by either copper sulfate (CuSO(4)) or 2,2'-azo-bis(2-amidinopropane) hydrochloride (AAPH). Under such oxidant stress, FCBA and AEMA appear to possess antioxidant properties with respect to oxidation of LDL in a time-and concentration-dependent manner, as assessed by inhibition of thiobarbituric acid-reactive substances (TBARS) formation, conjugated diene production, and cholesterol degradation of oxidized LDL. In addition, both FCBA and AEMA exhibited a remarkable ability to rescue the relative electrophoretic mobility and fragmentation of the Apo B moiety of the oxidized LDL. Furthermore, FCBA and AEMA effectively protected the endothelial cells from the damaging effects of the CuSO(4)-oxidized LDL. Our findings suggest that the antioxidant properties of Antrodia camphorata may also provide effective protection from atherosclerosis.

Influence of dietary vitamin E supplementation on "heavy" pig carcass characteristics, meat quality, and vitamin E status.

Crossbred "heavy" pigs (average weight 120 kg, slaughter weight above 160 kg) were supplemented with all-rac-alpha-tocopheryl acetate during the last 60 d of late finishing at doses of 25 (control), 50, 100, 200, or 300 mg/kg of diet. At the end of this period, the pigs were slaughtered. Carcass characteristics and the meat quality of pork chops from longissimus muscle (LM) at the last lumbar vertebra were evaluated on eight barrows from each dosage group. Alpha-tocopherol levels were determined in plasma during supplementation and in LM muscle after slaughter. Thiobarbituric acid reactive substances (TBARS) and drip loss were also evaluated in meat. Plasma alpha-tocopherol levels increased (P < .005) during supplementation in treated animals compared to controls, with a peak at 40 d. Alpha-tocopherol levels were higher (P < .05) in LM from pigs treated with 300 mg/kg than in controls (8.4 vs 5.6 microg/g). Dressing percentages correlated (P < .05) with the ratio of plasma alpha-tocopherol levels to the sum of cholesterol and triglycerides. Inhibition of TBARS during storage was related (P < .005) to vitamin E supplementation level, but drip losses in chops were not related to supplementation levels. We concluded that dietary vitamin E supplementation to heavy pigs during the last 60 d of finishing improves dressing percentage, reduces lipid oxidation, and increases the alpha-tocopherol concentration of tissues.