Biodegradation kinetics of 2,4-dichlorophenol by acclimated mixed cultures

The biodegradation kinetics of 2,4-dichlorophenol (2,4-DCP) by culture (Culture M) acclimated to mixture of 4-chlorophenol (4-CP) and 2,4-DCP and the culture (Culture 4) acclimated to 4-CP only were investigated in aerobic batch reactors. Also, pure strains isolated from mixed cultures were searched for their ability towards the biodegradation of 2,4-DCP. Culture 4 was able to completely degrade 2,4-DCP up to 80 mg/L within 30 h and removal efficiency dropped to 21% upon increasing initial concentration to 108.8 mg/L. When the Culture M was used, complete degradation of 2,4-DCP in the range of 12.5-104.4 mg/L was attained. A linear relationship between time required for complete degradation and initial 2,4-DCP concentrations was observed for both mixed cultures. It was observed that the Haldane equation can be used to predict specific degradation rate (SDR) (R(2)>0.99) as a function of initial 2,4-DCP concentrations and it adequately describes 2,4-DCP concentration profiles. Both of the mixed cultures settled well, which is important to maintain good removal efficiency for longer periods of time for real full-scale applications. Although the pure strains isolated from mixed cultures were found to have higher SDR of 2,4-DCP compared to mixed cultures, they did not settle well under quiescent conditions.     

The Relationship Between Taurine and 3-Nitrotyrosine Level of Hepatocytes in Experimental Endotoxemia

It has been proposed that taurine may function as an oxidant in a dose-dependent manner in vivo and in vitro. The present study was carried out to investigate the relationship between taurine concentration and 3-nitrotyrosine level, a stable marker of peroxynitrite action, in hepatocytes of guinea pig in endotoxemia before and after taurine administration. The levels of taurine and 3-nitrotyrosine were measured by HPLC method. In the present study, taurine was low concentration in hepatocytes exposed to endotoxemia. In taurine plus endotoxin treated animals, HPLC analysis showed higher taurine level compared with animals only supplemented with taurine. But 3-nitrotyrosine levels were same in both taurine alone and taurine plus endotoxin groups. In conclusion, taurine is able to prevent the damaging effect of peroxynitrite, at concentration measured in hepatocytes, in our experimental conditions.     

Protective effect of modified glucomannans and organic selenium against antioxidant depletion in the chicken liver due to T-2 toxin-contaminated feed consumption

The aim of this work was to assess the effect of T-2 toxin on the antioxidant status of the chicken and to study possible protective effects of modified glucomannan (Mycosorb) and organic selenium (Sel-Plex). Inclusion of T-2 toxin in the chickens' diet (8.1 mg/kg for 21 days) was associated with significant decreases in the concentrations of selenium (Se)(by 32.2%), alpha-tocopherol (by 41.4%), total carotenoids (by 56.5%), ascorbic acid (by 43.5%) and reduced glutathione (by 56.3%) in the liver, as well as a decrease in the hepatic activity of Se-dependent glutathione peroxidase (Se-GSH-Px) (by 36.8%). However, inclusion of modified glucomannans into the T-2 toxin-contaminated diet provided a partial protection against the detrimental effects of the mycotoxin on the antioxidant defences in the chicken liver. For example, the Se concentration in the liver was restored completely, although the Se-GSH-Px activity in the liver increased to only 81% of its control value. These protective effects of modified glucomannas were associated with a 45% reduction of lipid peroxidation in the liver in comparison to the effects of T-2 toxin alone. A combination of modified glucomannas with organic Se was shown to provide further protection against toxin-induced antioxidant depletion and lipid peroxidation in the chicken liver. Thus, the data clearly indicate a major protective effect of the mycotoxin-binder in combination with organic Se against the detrimental consequences of T-2 toxin-contaminated feed consumption by growing chickens.     

Characterization of wound-induced serine protease inhibitor (wip1) genes and proteins in Turkish maize varieties

Protease inhibitors (PIs) are generally small proteins that have been identified in plants. The wip1 gene codes for wound-induced protein, which is similar to serine PIs of the Bowman-Birk family (BBIs). In this study, we analyzed 10 wip1 genes of Turkish maize varieties to understand the structure and characteristics of the wip1 genes and proteins in maize. We found that genetic variability of wip1 genes was higher (π: 0.0173) than reported in previous studies. Tajima’s D value was found to be positive (1.73), suggesting over-dominant selection in these loci. According to phylogenetic analysis of wip1 proteins, monocot and dicot BBIs were separated independently, and Turkish varieties were clustered with each other generally. The 3D structures of wip1 proteins indicated that several wip1 proteins had structural divergence in active loops, containing various numbers of cysteine residues ranging between 7 and 9. Particularly, Cys74 was identified in Kocbey and Gozdem varieties, whereas Cys98 was only in the Gozdem variety. Also, a critical serine residue (Ser98) was observed in two varieties — Antbey and Batem Efe. These results can contribute to understanding the role of wip1 genes and corresponding proteins in maize.     

Effects of maternal dietary supplementation with three sources of carotenoids on the retinyl esters of egg yolk and developing quail liver

The effects of supplementation of the maternal diet of quail with three natural sources of carotenoids (alfalfa nutrient concentrate (PX agrotrade mark), tomato powder and marigold extract) on the accumulation of retinol and retinyl esters in egg yolk and in the liver of the new hatchling and maternal were investigated. The present study showed that the vitamin A in quail egg yolk was present in 4 different forms, namely retinol (R 52-62%), retinyl linoleate (RL 9-11%), retinyl stearate (RS 4%), retinyl oleate (RO 11-15%) and retinyl palmitate (RP 13-22%). The retinyl ester profile of the liver of newly hatched quail (R 2-4%, RL 8-12%, RS 19-21%, RO 12-15%, RP 50-55%) differs from that of egg yolk but was similar to that of the liver of adult quail (R 1%, RL 5-6%, RS 21-28%, RO 9-12%, RP 54-63%). It has been shown that RO and RP concentrations in egg yolk and the liver of day old quail chick significantly increased as a result of carotenoid supplementation of the maternal diet.     

Effects of Taurine on Nitric Oxide and 3-Nitrotyrosine Levels in Spleen During Endotoxemia

Taurine (2-aminoethanesulfonic acid) is a free sulfur-containing β-amino acid which has antioxidant, antiinflammatory and detoxificant properties. In the present study, the role of endotoxemia on peroxynitrite formation via 3-nitrotyrosine (3-NT) detection, and the possible antioxidant effect of taurine in lipopolysaccharide (LPS)-treated guinea pigs were aimed. 40 adult male guinea pigs were divided into four groups; control, endotoxemia, taurine and taurine+endotoxemia. Animals were administered taurine (300 mg/kg), LPS (4 mg/kg) or taurine plus LPS intraperitoneally. After 6 h of incubation, when highest blood levels of taurine and endotoxin were attained, the animals were sacrificed and spleen samples were collected. The amounts of 3-nitrotyrosine and taurine were measured by HPLC, and reactive nitrogen oxide species (NOx) which are stable end products of nitric oxide was measured spectrophotometrically in spleen tissues. LPS administration significantly decreased the concentration of taurine whilst increased levels of 3-NT and NOx compared with control group. It was determined that taurine treatment decreased the levels of 3-nitrotyrosine and NOx in taurine+endotoxemia group. The group in which taurine was administered alone, contradiction to well-known antioxidant effect, taurine caused elevated concentration of 3-NT and NOx. This data suggest that taurine protects spleen against oxidative damage in endotoxemic conditions. However, the effect of taurine is different when it is administered alone. In conclusion, taurine may act as an antioxidant during endotoxemia, and as a prooxidant in healthy subjects at this dose.     

Assessment of genetic diversity of wheat genotypes by resistance gene analog-EST markers

Resistance gene analog-expressed sequence tag (RGA-EST)-based markers have been used for variety discrimination and studies of genetic diversity in wheat. Our aim is to increase the competitiveness of public wheat breeding programs through intensive use of modern selection technologies, mainly marker-assisted selection. The genetic diversity of 77 wheat nucleotide binding site (NBS)-containing RGA-ESTs was assessed. Resistant and susceptible bread wheat (Triticum aestivum) genotypes were used as sources of DNA for PCR amplifications. In our previous studies, the F? individuals derived from the combinations PI178383 x Harmankaya99, Izgi2001 x ES14, and Sonmez2001 x Aytin98 were evaluated for yellow rust resistance at both seedling and adult stages to identify DNA markers. We have now examined the genetic variability among the resistant and susceptible Turkish wheat cultivars for yellow rust disease and the mean genetic distance between the cultivars. The highest similarity was 0.500 between Harmankaya99 and Sonmez2001. The lowest similarity was 0.286 between Aytin98, PI178383 and Aytin98, ES14. A relatively high level (49.5%) of polymorphism was observed with 77 RGA-EST primers across the six wheat genotypes, despite the fact that all of them were local cultivars from geographically close locations. RGA-EST sequences were compared by BlastX algorithms for amino acid sequences to determine the polymorphic categories among the combinations. BlastX analyses of six RGA-ESTs that gave polymorphic patterns for all combinations were NBS-LRR class RGA, NB-ARC domain containing protein, NBS-type resistance protein RGC5, NBS-LRR-S/ TPK stem rust resistance protein, and putative MLA1 proteins, while 38 RGA-EST gave a monomorphic pattern.