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Number of results: 4
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Abstract

Applying pesticides to crops is one of the causes of water pollution by surface runoff, and chlorpyrifos, trifluralin and chlorothalonil are used respectively as insecticide, herbicide and fungicide for crop plants widely. To explore effects of three pesticides on aquatic organisms, superoxide dismutase (SOD) and glutathione S-transferase (GST) activities were determined after 24 h and 48 h exposure of D. magna with ages of 6–24 h to several low concentrations of chlorpyrifos (0.36, 0.72, 1.43, 2.86, 5.72 μg∙L−1), trifluralin (0.17, 0.33, 0.66, 1.33, 2.65 mg∙L−1) and chlorothalonil (0.09, 0.18, 0.36, 0.72, 1.43 mg∙L−1) respectively. Main reproductive parameters including first pregnancy time, first brood time, the number of first brood and total fecundity after 21 d exposures at the same concentrations of pesticides as described above were also measured. The results showed that the activities of GST increased in lower concentrations and decreased in higher concentrations after 24 h exposure to three pesticides, respectively. The activities of SOD showed the same changes after 48 h exposure. With the time prolonged, the activities of GST decreased while the activities of SOD increased. After 21 d exposure, the first pregnancy time and first brood time were delayed, while the number of the first brood and total fecundity per female decreased with increasing concentrations. These results corroborated that GST activity was more sensitive to those pesticides than SOD activity, and there was a significant relationship between total fecundity and pesticides-dose(r>0.94, n=6), GST activity after 48 h exposure and total fecundity after 21 d exposure (r>0.92, n=6).
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Abstract

In our previous Genome-wise Association Study we found that Cystic Fibrosis Transmem- brane Conductance Regulator gene (CFTR) is a candidate gene for sperm motility in fresh semen of Holstein-Friesian bulls. Since in cows thawed semen is commonly used for the artificial insem- ination (AI) we have decided to find out whether functional polymorphism within CFTR gene coding sequence is associated with selected parameters of thawed sperm, including their motility evaluated by computer-assisted sperm analysis (CASA), the activity of three antioxidant enzymes: glutathione peroxidase (GPx) catalase (CAT), superoxide dismutase (SOD), ATP con- tent and integrity of sperm membranes. One hundred twenty Holstein Friesian bulls kept in uni- form environmental conditions (one AI company) were included in the study. Significant associ- ations between genotypes of missense mutation within exon 11 of the CFTR gene (Met468Leu) and the activity of antioxidant enzymes and sperm mitochondrial function were revealed. No effect of CFTR genotypes on sperm motility was observed. Significant differences in CAT and SOD activity were found between AA and TT homozygous individuals. Bulls with TT genotype had the lowest activity of both antioxidant enzymes. The same bulls also showed the lowest num- ber of sperm with active mitochondria. Our results demonstrate that missense mutation Met468Leu within CFTR gene is associated with antioxidant enzyme activity and mitochondrial function of bovine thawed sperm without affecting their motility.
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Abstract

Chitin deacetylase is the only known enzyme which is able to deacetylate N-acetyl-D-glucosamine units in chitin or chitosan chains. As chitin can hardly be dissolved in organic/inorganic solvents, new solvents are still searched. Ionic liquids are promising for that application and for homophase enzymatic deacetylation. The aim of the work was to investigate the influence of selected ionic liquids on activity of chitin deacetylase. It has been shown that [Amim] ionic liquids increase the activity of chitin deacetylase. The highest activity was observed for [Amim][Cl]. Ionic liquids with shorter (ethyl (C2)) and longer side chain (buthyl (C4)) only insignificantly influenced the activity of the enzyme. All tested ionic liquids with [Br] anion increased the activity of chitin deacetylase while the [Emim] and [Bmim] cation in combination with [Cl] anion inhibited the activity of the enzyme.
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Abstract

Three transgenic soybean lines expressing the Cry1Ia5 gene were developed using the Agrobacterium transformation system. The integration of the Cry1Ia5 gene in the genome of the transgenic plants was approved using specific primers for PCR and real time PCR analysis, respectively. The insecticidal activity of three transgenic lines (L1, L2 and L3) against 2nd larval instars Spodoptera littoralis was tested. The data indicate that L2 exhibited the highest mortality percentage 9 days post feeding (60%) followed by L3 (40%) then L1 (20%) while the control showed 0% mortality. The larvae fed transgenic material appeared smaller in size than compared to the control larvae. The reduction in insect size and weight was due to the accumulation of higher phenoloxidase activity in insect tissues. The higher mortality observed in L2 was due to a significant decrease in the acetylcholine esterase activity that leads to accumulation of acetylcholin at higher levels which causes paralysis and death. The developed transgenic line 2 could be used to construct an insect resistant soybean cultivar.
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