Modification of the effects of aflatoxin B1 on the glutathione system and its regulatory genes by zeolite

The purpose of the present study was to use oxidative stress markers for investigating the effect of zeolite (315 mg/kg of complete feed) in the case of aflatoxin B1 contamination (92 μg/kg complete feed). In a 21-day feeding trial with broiler chickens, oxidative stress parameters such as conjugated dienes, conjugated trienes, malondialdehyde, reduced glutathione content and glutathione peroxidase activity were not changed significantly by supplementation with this mycotoxin absorbent. The relative gene expression of transcription factors KEAP1 and NRF2 was not modified by the absorbent either. Still, the expression of GSS, GSR and GPX4 genes increased significantly due to the aluminosilicate supplementation. The results suggest that zeolite reduced lipid peroxidation in the blood plasma but not in the red blood cell haemolysate or the kidney. The relative expression of the genes encoding the glutathione redox system also changed as a result of zeolite supplementation, but these changes were not found at the protein level.

Step-wise and one-pot synthesis of highly substituted conjugated trienes from 2-oxobenzo[h]chromenes/2H-pyran-2-ones

The synthesis of conjugated trienes by ring contraction of 2-oxobenzo[h]chromenes/2H-pyran-2-ones followed by decarboxylative rearrangement has been developed.

Analysis of Pro- and Antioxidant Status in Women with Endocrine Infertility

The aim of our study was to identify the changes in the indicators of lipid peroxidation (LPO) and antioxidant defense (AOD) in women with endocrine infertility. Methods and Results: The study included 358 women of reproductive age. Based on clinical and laboratory data, two groups were formed: the control group (CG) and the main group (MG). CG consisted of 61 healthy fertile women (mean age of 22±2.3 years). MG consisted of 297 women (mean age of 26±5.6 years) with endocrine infertility. The blood levels of antioxidant parameters (total antioxidant activity [TTA], SOD activity, α-tocopherol and retinol) and primary/secondary products of LPO (conjugated dienes [CD], ketodienes and conjugated trienes [KD-CT], and thiobarbituric acid reactants [TBARs]) were determined using spectrophotometric and fluorometric methods. The levels of sex hormones and cortisol were determined by radioimmunoassay and EIA. In MG, we found a significant increase in the blood levels of total lipid, DB, CDs, KD-CT, and TBARs, compared to CG. The results of a comparative analysis of the AOD parameters showed a significant increase in the total AOA level by 31% in MG, while the levels of α-tocopherol and retinol significantly decreased by 22% and 15%, respectively, compared to CG. In women of MG, the serum level of prolactin increased by 2 times. Conclusion: The results obtained reflect the adaptive and disadaptive mechanisms of LPO-AOD participation in the formation of female infertility of endocrine origin. The complex changes in the LPO-AOD system (increased levels of the substrates of oxidation and all intermediates of the LPO process amid falling values of the AOD parameters) indicate the presence of OS in women with endocrine infertility.

Рarameters of Oxidative Stress in Women with Diffuse Mastopathy in the Menstrual Cycle Course

Background: Despite the active study of the main pathogenetic mechanisms of benign breast diseases, there is still insufficient information on the lipid peroxidation – antioxidant defense processes activity in women with diffuse mastopathy in the course of menstrual cycle. Such knowledge is necessary for the early detection and prevention of hyperplastic processes and for the development of pathogenically based antioxidant therapy. Research hypothesis: the parameters of the lipid peroxidation – antioxidant defense system in women with diffuse mastopathy vary depending on the period of the menstrual cycle. Objective: to assess the activity of lipid peroxidation and antioxidant system reactions in women with diffuse mastopathy during the menstrual cycle. Materials and Methodology: The study included 29 women: 12 healthy ones (mean age 29.6 ± 2.32 years) and 17 women with diffuse mastopathy (mean age 28.8 ± 3.2 years). All women underwent standard collection of anamnesis and clinical examinations. For all women laboratory tests were performed to determine the concentration of lipid peroxidation products and antioxidant defense components. The tests were conducted every 3 days – on days 1–3, 4–6, 7–9, 10–12, 13–15, 16–18, 19–21, 22–24, and on days 25–28. Spectrophotometric and fluorometric methods were used. Results: Patients with diffuse mastopathy showed an increase in double bonds on days 1–3 (by 1.3 times), days 7–9 (by 1.22 times), 19–21 (by 1.19 times), and on days 22–24 (by 1.53 times); in conjugated dienes – on days 1–3 (by 1.4 times), 4–6 (by 1.2 times), 7–9 (by 1.47 times), 16–18 (by 1.48 times; P = .02), and on days 19–21 (by 1.38 times); in ketodienes and conjugated trienes (during the whole cycle) – on days 1–3 (by 2.64 times), 4–6 (by 1.6 times), 7–9 (by 1.72 times), 10–12 (by 1.39 times), 13–15 (by 1.36 times), 16–18 (by 3.46 times), 19–21 (by 2 times), 22–24 (by 2.54 times), and on days 25–28 (by 3.1 times); in thiobarbituric acid reactants – on days 19–21 (by 1.36 times) and 22–24 (by 1.27 times) compared with the control group. Patients with diffuse mastopathy showed an increase in total antioxidant activity on days 10–12 (by 1.67 times) and 16–18 (by 1.5 times); a decrease in superoxide dismutase activity – on days 16–18 (by 1.09 times) and 25–28 (by 1.25 times), in oxidized glutathione levels – on days 16–18 (by 1.23 times), 22–24 (by 1.14 times), and days 25–28 (by 1.25 times); an increase in reduced glutathione – on days 1–3 (by 1.3 times); a decrease in retinol content – on days 1–3 (by 1.64 times), 4–6 (by 1.2 times; P = .044), 10–12 (by 1.36 times), 19–21 (by 1.24 times) and on days 25–28 (by 1.18 times), and in ascorbate content – on days 7–9 (by 1.11 times) and 10–12 (by 1.16 times). Conclusion: During our study, we revealed an imbalance of lipid peroxidation – antioxidant defense system. For normalizing the balance in lipid peroxidation – antioxidant defense system, patients with diffuse mastopathy in the luteal phase of the menstrual cycle are recommended to use antioxidant drugs. To prove the general hypothesis further clinical trials are warranted.

Temperature Dependence of Oxidation Kinetics of Extra Virgin Olive Oil (EVOO) and Shelf-Life Prediction

Producers have to guarantee the extra virgin olive oil (EVOO) quality characteristics reported in the Regulation (CEE) 2568/91 throughout the product shelf-life (SL). Unfortunately, due to the development of oxidative reactions, some quality indices change during storage leading to a progressive deterioration of EVOO quality. To avoid the risk of product downgrading in the virgin oil category, the development of effective shelf-life prediction models is extremely important for the olive oil industry. In this research, the accelerated shelf-life testing (ASLT) protocol was applied to evaluate the temperature dependence of selected oxidation indexes as well as to develop a shelf-life predictive model. The evolution of conventional (peroxide value, K232, K270, polyphenols, tocopherols and hexanal) and unconventional parameters (conjugated trienes and pyropheophytin a) was monitored in bottled EVOO stored in the dark at increasing temperature (25, 40, 50 and 60 °C). Accordingly, for well-packed products with reduced oxygen in headspace, the best shelf-life index allowing the ability to predict EVOO SL turned out to be K270. In addition, pyropheophytin a (%) has been shown to be more sensitive to temperature changes than the secondary oxidation indices, thus suggesting its use as a freshness indicator for storage temperatures higher than 25 °C.

An insight into regioselectivity in the transformation through a ruthenacycle

Ru(0)-Catalysed cross-dimerisation of unsymmetrical internal alkynes with conjugated dienes yields two conjugated trienes depending on the regioselectivity. The regioselectivity is dominantly controlled by the induction effect of the substituents.

Stereoselective synthesis of conjugated trienes via 1,4-palladium migration/Heck sequence

An efficient 1,4-palladium migration/Heck sequence was developed for the highly stereoselective synthesis of conjugated trienes.

Oxidative stabilization of corn oil with spinach extract

The present study was aimed to analyze the antioxidant activity of spinach (Spinacia oleracea) extract in oxidative stabilization of refined, bleached and de-odorized (RBD) corn oil (CO). Corn oil was supplemented with three different concentrations 600, 1200 and 1800 ppm of methanolic spinach extract and then stored at 25oC and 60oC. Different oxidation measuring parameters such as peroxide value (PV), free fatty acid (FFA) value, iodine value (IV), conjugated dienes (CD), conjugated trienes (CT) and para-anisidine value (PAV) were examined. The potency of spinach extract as natural antioxidant was found to be as effective as the synthetic antioxidants BHA and BHT used as standards and highest stabilization was observed in the order CO-1800>CO-1200>CO-BHT> CO-BHA>CO-600>CO-control. The results showed a significant effect of spinach extract in enhancing the oxidative stability of corn oil. Bangladesh J. Sci. Ind. Res.54(4), 375-382, 2019

The ratio of erythrocyte populations in the blood of puppies during postnatal oxidative stress

The article presents new scientifi c data on the ratio of erythrocyte populations in puppies' blood during postnatal oxidative stress. It was established that the number of erythrocytes in the blood of one-day-old puppies was 5.64 ± 0.12 T / l, and half of these cells belonged to the population of "mature", 40% - "young" and 10% - "old". In day-old puppies, the content of lipid peroxidation products in erythrocyte hemolysates is quite high, which indicates the development of postnatal oxidative stress. Thus, the content of diene conjugates, ketodienes and Schiff bases is respectively 1,406 ± 0,023 Conv. units, 0.676 ± 0.004 Conv. units and 0.135 ± 0.003 Conv. units. From one to fi ve days age of puppies the number of erythrocytes in the blooddecrease by 1.5 times (p<0.001), mainly due to the decrease in the number of "mature" cells (by 1.6 times; p<0.001). The intensity of peroxide oxidation in the body of puppies even a month after birth is relatively high, as indicated by the content of Schiff bases in the erythrocytes of the blood of these animals - 0.185 ± 0.002 Conv.units. The inverse correlations of the content of Schiff bases in erythrocyte hemolysate with their number in the bloodstream were found to be r = -0.83 (p<0.001). It should also be noted the direct correlation of the content of diene conjugates in the blood of puppies with the number of erythrocytes in their blood (r = 0,58 p <0,05), but the content of ketodienes and conjugated trienes is inversely related to the content of "young" erythroid cells in the puppies' blood (r = -0.57 p <0.05). Consequently, post-natal adaptation of puppies results in the replacement of fetal erythrocytes by postnatal cells, and this process is associated with the intensifi cation of peroxide oxidation and accumulation of the end products of peroxidationin the cells. This process isaccompanied by an acceleration of the process of "aging" of young forms of erythrocytes, as a result of which prerequisites for the development of anemiaare created. Key words: erythrocytes, oxidative stress, puppies, Schiff bases, ketodienes, diene conjugates.

Oxidative Stability of Soybean Oil Supplemented with Pod Coat Extracts of Cluster Bean

The aim of present work was to determine the potency of phenolic extracts from cluster bean pod coats in improving shelf life of soybean oil. Pod coats of cluster bean were extracted with three solvents (acetone, ethylacetate and chloroform). Crude soybean oil samples were stabilised by adding different extracts at 1000 and 2000 ppm concentration and effect of addition of these extracts on oxidative stability of crude soybean oil at 50°C was observed. Rate of oxidative degradation of crude soybean oil was lowest in the sample treated with acetone extract (2000 ppm). The value of various oxidative quality parameters of crude soybean oil supplemented with acetone extract (2000 ppm) after 28 days of incubation are peroxide value (26.77 meq/kg oil), free fatty acids content (2.637%), p-anisidine value (25.18), TOTOX value (78.72), conjugated dienes (28.47%), conjugated trienes (13.97%) and TBA value (31.59 meq malonaldehyde/g). Results of present study indicate that pod coat extracts of cluster bean possess remarkable antioxidant potential and considerably lowered the rate of oxidative deterioration of crude soybean oil.