Search results for "peroxidases"
showing 6 items of 26 documents
Gold Nanoparticles Supported on Nanoparticulate Ceria as a Powerful Agent against Intracellular Oxidative Stress
2012
Ceria-supported gold nanoparticles are prepared exhibiting peroxidase activity and acting as radical traps. Au/CeO2 shows a remarkable biocompatibility as demonstrated by measuring cellular viability, proliferation, and lack of apoptosis for two human cell lines (Hep3B and HeLa). The antioxidant activity of Au/CeO2 against reactive oxygen species (ROS) is demonstrated by studying the cellular behavior of Hep3B and HeLa in a model of cellular oxidative stress. It is determined that Au/CeO2 exhibits higher antioxidant activity than glutathione, the main cytosolic antioxidant compound, and its CeO2 carrier. Overall the result presented here shows the potential of implementing well-established …
Enzymatic, physicochemical, nutritional and phytochemical profile changes of apple (Golden Delicious L.) juice under supercritical carbon dioxide and…
2018
The impact of supercritical carbon dioxide (SCCD) (10-60 MPa/45 °C/30 min) and subsequent 10 weeks storage at 4 °C on polyphenol oxidase (PPO), peroxidase (POD) activities, phenolic profile, vitamin C, sugars, physicochemical properties of cloudy apple juices was investigated. No significant changes in sugars and total polyphenols were observed, whereas significant degradation (≈28%) of vitamin C and individual polyphenols (≈18%) was noted after SCCD treatment. After 4 weeks storage only 34% of vitamin C was retained and no vitamin C was detected after this time. Ten weeks of storage caused hydrolysis of sucrose in 15%, whereas degradation of individual polyphenols ranged from 43 to 50% dep…
Different strategies to achieve Pb-tolerance by the two Trebouxia algae coexisting in the lichen Ramalina farinacea.
2012
Lichen thalli are permeable to airborne substances, including heavy metals, which are harmful to cell metabolism. Ramalina farinacea shows a moderate tolerance to Pb. This lichen comprises two Trebouxia phycobionts, provisionally referred to as TR1 and TR9, with distinct physiological responses to acute oxidative stress. Thus, there is a more severe decay in photosynthesis and photosynthetic pigments in TR1 than in TR9. Similarly, under oxidative stress, antioxidant enzymes and HSP70 protein decrease in TR1 but increase in TR9. Since Pb toxicity is associated with increased ROS formation, we hypothesized greater Pb tolerance in this phycobiont. Accordingly, the aim of the present study was …
Harnessing nature's insights: synthetic small molecules with peroxidase-mimicking DNAzyme properties.
2011
International audience
Dissociation of airway responsiveness and bronchoalveolar lavage (BAL) cell composition in sensitized guinea-pigs after daily inhalation of ovalbumin
1994
Summary. The association between inflammatory cell influx, cell activation status and change of airway responsiveness to acelylcholine (ACh) after daily inhalation of ovalbumin (OA) in sensitized guinea–pigs was investigated. Starting 3 weeks after sensitization (OA at 50mg/kg s.c. + i.p.) guinea–pigs were exposed daily to 2% OA (10min: undercover of 0.5Smg/kg mepyramine i.p. 15min before OA) for 2 weeks. Concentration–response curves (CRCs) for inhaled ACh were performed 24 h after the last OA–challenge and 24 h after another single OA–inhalation 1 week later. CRCs for inhaled ACh were neither affected 24 h after the last OA challenge (daily for two weeks) nor 24 h after another OA–inhalat…
Comparison of oxidoreductive enzyme activities in three coal tar creosote-contaminated soils
2019
This study used laboratory experiments to compare the effects of coal tar creosote on the activity of oxidoreductive enzymes in sandy loam, loamy sand and sandy clay loam soils. Different amounts of coal tar creosote were added to soil samples as follows: 0 (control), 2, 10 or 50 g kg–1 dry matter. The activity of soil dehydrogenases (DHAs), o-diphenol oxidase (o-DPO), catalase (CAT), nitrate reductase (NR) and peroxidases (POX) was determined. Contamination of soil with coal tar creosote affected oxidoreductase activity. Oxidoreductive enzyme activity following soil contamination with coal tar creosote was in the following order: DHAs > CAT > NR > POX > o-DPO in…