Onur Atakisi

Subclinical mastitis causes alterations in nitric oxide, total oxidant and antioxidant capacity in cow milk.

The aim of this study was to investigate total antioxidant (TAC), and oxidant capacity (TOC) and nitric oxide (NO) levels in milk of cows with subclinical mastitis. Brown Swiss and Holstein breed cows were screened with California Mastitis Test (CMT) to determine mammary glands with subclinical mastitis. Moreover, somatic cell counts (SCC) were determined electronically in all milk samples. Mammary quarters were classified as healthy (n=25) or subclinical mastitis (n=35) based on CMT scores and somatic cell count (SCC: < or =200,000/ml or >200,000/ml) in milk. Nitric oxide, TOC and SCC levels were significantly higher (p<0.001, p<0.005 and p<0.001, respectively) in milk from mammary quarters with subclinical mastitis compared to those from healthy mammary quarters. In conclusion, subclinical mastitis results in higher NO concentrations, TOC and SCC, and NO and TOC were positively correlated with SCC. Moreover, alterations in NO levels and TOC in milk could be used as an alternative diagnostic tool to screen for subclinical mastitis.

Histopathologic, biochemical and genotoxic investigations on chronic sodium nitrite toxicity in mice.

The aim of this study was to investigate the effects of long term Sodium nitrite (NaNO2) consumption. Swiss albino mice were given NaNO2 (0, 10 and 20 mg/kg/day) as mixed in feed for 8 months. At the end of treatments, animals were sacrificed and selected organs were processed for histopathologic, imunohistochemical, biochemical and genotoxic investigations. Mild to moderate degenerative changes were observed in liver, kidney, intestine, lung and spleen of NaNO2-given mice. Inducible nitric oxide synthase and nitrotyrosine activities increased in liver and kidney of NaNO2-given mice. Proliferating cell nuclear antigen activity increased in liver. Apoptotic cell death was observed in livers of the treatment groups. Liver malondialdehyde level was higher in the treatment groups while no change was seen in kidney. Nitric oxide levels in both liver and kidney of the treatment groups were lower than those of the control group. In genotoxic investigations, the number of chromosome and chromatid breaks, chromatid association, and polyploidy increased while mitotic index decreased in NaNO2-given mice. The results showed that NaNO2 would cause histopathologic changes, nitrosative tissue damage, and lipid peroxidation in liver and kidney, as well as induce chromosomal aberrations even if it was given at low levels for long time.

Total oxidant and antioxidant capacities and nitric oxide levels in cattle with traumatic reticuloperitonitis

TRAUMATIC reticuloperitonitis (TRP) is a relatively common disease in adult cattle resulting from trauma caused by ingested foreign bodies ([Radostitis and others 1994][1], [Aiello 1998][2]). These foreign bodies, such as nails or pieces of wire, perforate the wall of the reticulum and cause various

A novel detergent additive: Organic solvent- and thermo-alkaline-stable recombinant subtilisin

Subtilisins are serine alkaline proteases produced by Bacillus species. For the personal care industry, thermo-active and stable under alkaline conditions protease variants are of especial interest for detergent formulations. In the present work, subtilisin gene from Bacillus subtilis PTTC 1023 was synthesized, cloned into the vector pD441-NH and expressed in E. coli BL21 (DE3). Recombinant subtilisin was purified in a single-step procedure by affinity chromatography. The molecular mass of the purified protein was determined to be about 40kDa by SDS-PAGE. The optimum pH and temperature values of its proteolytic activity were 10.5 and 50°C, respectively and retained more than 70% and 89% of its activity in pH range of 7–12 and 30–60°C, respectively. Enzyme purity was estimated to be about 200- fold greater than that of the crude extract and subtilisin had a specific activity of 56.16U/mg, with a yield of about 87.9%. It was completely inhibited by phenylmethanesulfonyl fluoride, which strongly suggests its belonging to serine protease family. Interestingly, subtilisin protease displayed a significant compatibility with commercial detergents, and tolerance organic solvent, metal ion and surfactant. The findings obtained demonstrated that protease of B.subtilis could potentially be used in future applications as an additive in detergent formulations.In the present work, subtilisin gene from Bacillus subtilis PTTC 1023 was synthesized, cloned into the vector pD441-NH and expressed in E. coli BL21 (DE3). Recombinant subtilisin was purified in a single-step procedure by affinity chromatography. The molecular mass of the purified protein was determined to be about 40kDa by SDS-PAGE. The optimum pH and temperature values of its proteolytic activity were 10.5 and 50°C, respectively and retained more than 70% and 89% of its activity in pH range of 7-12 and 30-60°C, respectively. Enzyme purity was estimated to be about 200- fold greater than that of the crude extract and subtilisin had a specific activity of 56.16U/mg, with a yield of about 87.9%. It was completely inhibited by phenylmethanesulfonyl fluoride, which strongly suggests its belonging to serine protease family. Interestingly, subtilisin protease displayed a significant compatibility with commercial detergents, and tolerance organic solvents, metallic ions and surfactants. The findings obtained demonstrated that protease of B. subtilis could potentially be used in future applications as an additive in detergent formulations.

Proteinase K hybrid nanoflowers (P-hNFs) as a novel nanobiocatalytic detergent additive

In this study, enzyme-inorganic hybrid nanoflowers were synthesized using proteinase K and Cu2+ ions. The synthesized proteinase K-Cu2+ hybrid nanoflowers (P-hNFs) were characterized by their morphology and chemical point of view by using different techniques such as SEM, FTIR, EDX, and XRD. The proteolytic activities and some important characteristics such as optimum pH and temperature of the P-hNFs were also evaluated by comparison with free proteinase K. Optimum pH values of free proteinase K and P-hNFs were determined as pH 10 and pH 11, respectively. Optimum temperatures recorded for both free proteinase K (at pH 10) and P-hNFs (at pH 11) were 40 °C. In our study, for the first time, using some commercial detergents and surfactants, the utility of the P-hNFs as a detergent additive was also systematically evaluated. In these studies, the P-hNFs exhibited better activity than free proteinase K in the presence of all surfactants (CHAPS, DOC, SDS, Triton X-100 and Tergitol) except for Tween 80. Importantly, the P-hNFs was more stable and compatible with all tested solid laundry detergents. The findings demonstrated that the P-hNFs could potentially be used as an additive in detergent formulations.