Objectives: Menopause with oxidative imbalance causes metabolic disorders. These disorders are involved in the pathogenesis of various diseases. Olive leaf is a rich source of phenolic compounds that are biologically active and have better antioxidant activity, anti-inflammatory and radical scavenging effect. The aim of this study was to evaluate the effects of olive leaf extract on antioxidant activity of liver tissue in ovariectomized rats.Materials and Methods: In this study, 21 male Wistar rats weighting 220±20 g were randomly selected and were divided into three groups (n=7): 1) control group (healthy animals), 2) OVX group (ovaries removed by surgery) and 3) OVX-OLE group (ovaries removed and received olive leaf extract). The third group of animals received olive leaf extract for 30 days in dose of 100 mg/kg orally and through gavages. At the end of the study, samples of liver tissue were taken and the activities of super oxide dismutase (SOD), glutathione peroxidase (GPX), malondialdehyde (MDA) and catalase were measured.Results: The results showed that ovariectomy reduced rates of SOD (P=0.001), GPX (P=0.003) and catalase (P=0.001) significantly compared to controls. It was also found that the average level of MDA in OVX group than the OVX-OLE and control group was significantly higher (P=0.001).Conclusion: This study showed that oral administration of olive leaf can increase the activity of antioxidant ENZYMES in the liver tissue.

Soybean (Glycine max) is one of the tropical plants that are also cultivated in temperate regions. Because of the nutritional and medical importance of this crop and its sensitivity to growth medium temperature and vital role of impact biomembranes, the effect of low non-freezing temperature and plants response to it was investigated. Plants were exposed to 15°C (cold-acclimated) or 25oC (nonacclimated) for 24h, under 250 mmol m-2s-1 photo synthetically active radiations (PAR). Then all plants were exposed to 4oC (chilling temperature) for 24h and allowed to recover at 25oC for 24h. We analyzed the activity of ascorbate peroxidase (APX) and guaiacol peroxidase (GPX), electrolyte leakage in leaves and roots. Chilling sensitive soybean plants can be made tolerant to cold by cold acclimation via exposing the plants to nonfreezing low temperatures.

To assess nickel-induced toxicity in plants, Zea mays seeds were germinated and cultured on nutrient solution with nickel concentrations of 50-200 mM for a period of two weeks. Observed biological makers included biomass, soluble and total protein contents, and the activities of guaiacol peroxidase (GPX), ascorbate peroxidase (APX), catalase (CAT), and phenylalanine ammonia-lyase (PAL) in the leaves and roots of maize. The fresh and dry weight of leaves and roots increased in 50 mM nickel but decreased in 100 and 200 mM. Soluble and total protein contents were significantly increased by increasing nickel concentrations up to 200 mM nickel in both roots and leaves of maize. Significant increases of ascorbate peroxidase (the highest activity at 200 mM nickel), catalase (the highest activity at 50 mM nickel), and phenylalanine ammonia-lyase (the highest activity at 100 mM nickel) were observed in the leaves and roots of Zea mays seedlings at all tested nickel concentrations. Guiacol peroxidase activity was decreased in the leaves and roots of Zea mays seedlings exposed to different levels of nickel. The present results suggested that treatment with different levels of nickel may enhance the antioxidant activities in the leaves and roots of Zea mays seedlings, thus alleviate Ni-induced oxidative damage and enhance Ni tolerance.

BACKGROUND: Stocking density induced stress that affects energy intake, growth rate, enzymatic activity and oxygen consumption in fish. OBJECTIVES: In this study the development of antioxidant enzyme Glutathione peroxidase (GPX), catalase (CAT) and superoxide dismutase (SOD) in egg and larvae of rainbow trout (Oncorhynchus mykiss) that kept in different stocking density was investigated. METHODS:Four groups of eggs, cultured in pans (size16×9.5×10 cm, volume 10 L) with density of 400egg/l (group1 as routine density), 200egg/l (group2 as low density) and 600egg/l (group3 as high density) in triplicate. Eggs were held in tanks supplied with flow-through freshwater at 10.8oC. samples were taken at day1 (fertilization), 3 (Cleavage), 8(organogenesis), 16 (eyed egg), 31 (hatch) and 48 (active feeding). RESULTS:Asignificant increase in GPX and SOD activity was seen from fertilization till eggs were eyed. (p<0.001).The activity of these ENZYMES decreased to active feeding (p<0.001), meanwhile this activity was higher than the fertilization starts. Similar changes were seen in SOD and GPX activities in higher and lower densities (Group 2, 3). CAT activity increased from fertilization to organogenesis and then toward active feeding significantly decreased in compare to fertilization (p<0.001). Pattern of changes of catalase activity in high density group was similar to routine density but in low density group it was higher until eggs were eyed. GPX, SOD and CATactivities did not show significant difference in similar days among different groups (p<0.05). CONCLUSIONS: Our results showed that rearing densities used in this study could not affect antioxidant defense development in early life stages of O. mykiss.  

Reactive oxygen species, which lead to oxidative stress and related diseases via both intra- and extracellular pathways, could be identified and cleaning through some of the bacterial ENZYMES. Bearing in mind, the assessment of the structure, function and hosting of the ANTIOXIDATIVE ENZYMES while lead to disclose species of bacteria with probiotics capability, provides approaches to designing genetics constructs. In this regard, the nucleotide and protein sequences of the katA, katE, katE*, sodA, sodA*, gshR, gshR1, gshR4, trxB1 and trxR genes were retrieved from databases. Then the structural, functional,topological and physicochemical properties of the protein sequences of related ENZYMES were investigated. Moreover, their hosting in bacterial microorganisms were explored. The results of this study whilst disclosed the physicochemical properties of these ENZYMES reveal that KATE, KATA, KATE* and SODA are secretory capacity. Structural monitoring of these ENZYMES introduced collaborative and pragmatic domains with the ability to remove reactive oxygen species, hydrogen peroxide decomposition and regulation of redox reactions as well as immunomodulatory effects and ammonia removal in some of them. In this regard, examination the binding affinity of these ENZYMES to oxidant agents revealed high binding affinity of them, in particular KATA, to O2-. Additionally, checking the host of these ENZYMES revealed the presence of homologous sequences especially sequences like to TRXB1 and TRXR in different species of Weissella, Pediococcus, Leuconostoc, Tetragenococcus, Peptoniphilus and Listeria. Meanwhile, similarity search lead to detection seven encoding sequences with ANTIOXIDATIVE capacity in the genomic context of the Pediococcus acidilactici, Lactobacillus pentosus and Lactobacillus plantarum.