The aim of the study was to evaluate the impact of different rearing systems (organic, conventional and traditional) on the physicochemical properties and oxidation states of pork meat. Samples (M.biceps femoris) were obtained from producers directly 3 days after slaughtering. Chemical composition (dry matter, protein, collagen, fat, ash), colour (L*, a*, b*) and oxidation state (Thiobarbituric acid reactive substances -TBARS, free fatty acid -FFA and antioxidant capacity-2,2-diphenyl-1-picrylhydrazyl) of the meat samples were determined. The results indicated that the rearing system affects most of the evaluated parameters. The significant difference (P < 0.05) was observed in colour parameter L* and b*, where the conventional pork was darker and the organic pork yellower. Total protein content in meat of conventional pigs was higher, whereas the fat content in the meat of organically reared pigs was higher than the meat of pigs from both other rearing systems. Organic pork was more susceptible to oxidation process due to its higher TBARS and FFA values and lower antioxidant capacity, which may result in inferior technological properties of meat.

BACKGROUND: Lower limb skeletal muscle ischemia-reperfusion (IR) injury associated with increased morbidity and mortality is common in several clinical situations such as aortic aneurysms repairment, peripheral arterial surgery, vascular injury repairment, and shock. Although it is generally accepted that oxidative stress mediators have a significant role in IR injury, its precise mechanism is still unknown. Anecdotally, it is sustained not only by structural and functional changes in the organ it affects but also by damage to distant organs. The purpose of this report is to illustrate the effect of proanthocyanidin on IR injury. METHODS: In our study, 18 male Wistar albino rats were used. The subjects were divided into three groups of six each. (Group Control-C, Group Ischemia-Reperfusion -IR, Group Ischemia-Reperfusion and Proanthocyanidin-IR-PRO). Intraperitoneal proanthocyanidin was given to the IR and proanthocyanidin groups 30 minutes before laparotomy and 1-hour ischemia led to these two groups. After one hour, reperfusion started. Muscle atrophy-hypertrophy, muscle degeneration-congestion, fragmentation-hyalinization, muscle oval-central nucleus ratio, leukocyte cell infiltration, catalase enzyme activity, and TBARS were all examined in lower-limb muscle samples after one hour of reperfusion. RESULTS: When skeletal muscle samples were evaluated histopathologically, it was discovered that muscle atrophy-hypertrophy, muscle degeneration-congestion, fragmentation-hyalinization, and leukocyte cell infiltration with oval-central nucleus standardization were significantly higher in the IR group than group control and group IR-proanthocyanidin. Besides, oval-central nucleus standardization was significantly higher in the IR and proanthocyanidin group than in the control group. TBARS levels were significantly higher in the IR group than in the control and IR-proanthocyanidin groups while, catalase enzyme activity was found to be significantly lower in the IR group than in the control and IR and proanthocyanidin groups. CONCLUSION: As a consequence of our research, we discovered that proanthocyanidins administered before IR have a protective impact on skeletal muscle in rats. Further research in this area is required.

Cardiac aging is characterized by alterations in contractility and intracellular calcium ([Ca²⁺]_i) homeostasis. It has been suggested that oxidative stress may be involved in this process. We and others have reported that in cardiomyopathies the NADPH oxidase (NOX)-derived superoxide is increased, with a negative impact on [Ca²⁺]_i and contractility. We tested the hypothesis that in the aged heart, [Ca²⁺]_i handling and contractility are disturbed by NOX-derived superoxide. Contractility was evaluated isolated hearts, challenged with isoproterenol. To assess [Ca²⁺]_i, isolated cardiac myocytes were field-stimulated and [Ca^2+]_i was monitored with fura-2. Cardiac concentration-response to isoproterenol was depressed in aged compared to adults hearts (p < 0.005), but was restored by NOX inhibitors apocynin and VAS2870. In isolated cardiomyocytes, apocynin increased the amplitude of [Ca²⁺]_i in aged myocytes (p < 0.05). Time-50 [Ca²⁺]_i decay was increased in aged myocytes (p < 0.05) and reduced towards normal by NOX inhibition. In addition, we found that myofilaments Ca²⁺ sensitivity was reduced in aged myocytes (p < 0.05), and further reduced by apocynin. Finally SERCA levels but not phospholamban were reduced in aged hearts (p < 0.05). In conclusion, β-adrenergic‒induced contractility was depressed in aged hearts, and NOX inhibition restored back to normal. Moreover, altered Ca²⁺ handling in aged myocytes was also improved by NOX inhibition. These results suggest a NOX-dependent effect in aged myocytes at the level of Ca²⁺ handling proteins and myofilaments.

This study aimed to evaluate the antioxidant activities (AA) of lyophilized rosemary extract and lyophilized sage extract and their effects on the oxidative stability of poultry pátê. For this purpose, four poultry pátê formulations with rosemary, sage, sodium erythorbate, and a control (without antioxidants) were produced. The rosemary and sage were characterized according to total phenolic compounds (TPC), and AA by several methods. The poultry pátês stored at 4°C were evaluated by the lipid oxidation. High concentrations of TPC were detected in rosemary extract and sage extract (46.48 and 41.61 mg GAE/g: Gallic acid equivalent respectively). The AA of rosemary and sage extracts by free radical-scavenging were 4745.72 and 2462.82 µmol Trolox/g, respectively. The high concentration of catechin, rutin, myricetin and p-coumaric acids in these extracts may be responsible for the strong inhibitory action against food pathogens. Besides these compounds can be responsible for the best performance in inhibiting lipid oxidation in poultry pátês during the storage. This study suggests that rosemary and sage extracts may be used as a natural antioxidant in meat products.