guaiacol peroxidases (gp) are haem-containing enzymes participating in many physiological processes in plants. the expression pattern of these enzymes is organ-specific and developmentally regulated. methods: the presence of gp activity in extract samples, prepared from crocus sativus l. corms that were either dormant or rooting for 3, 6 and 10 days, was investigated. results: kinetic studies r...

We present evidence of two peroxidases in maize (Zea mays L.) mitochondria. One of these uses guaiacol and the other uses cytochrome c as the electron donor. Treatments of fresh mitochondria with protease(s) indicate that ascorbate and glutathione peroxidases are likely bound to the mitochondria as cytosolic contaminants, whereas guaiacol and cytochrome peroxidases are localized within the mito...

The atypical two-electron oxidation of thioanisole and its p-methyl, p-methoxy, and p-nitro analogues by horseradish peroxidase, contrary to earlier reports, stereoselectively produces the (8) sulfoxides in 6070% enantiomeric excess. Horseradish peroxidase reconstituted with 6-meso-ethylheme has little peroxidase (guaiacol oxidizing) activity, as previously reported, but exhibits increased sulf...

abstract kinetic properties of root of peroxidase of gundelia tournefortii investigated at different ph, temperature and different inhibitors. maximum activity of peroxidase achieved at ph 5.5-6 in according to type of substrate. activity of peroxidase increased at constant concentration of h2o2 and different concentration of guaiacol, catechol and pyrogallol. the maximum activity in presence o...

background: withania somnifera l. dunal, (ashwagandha) belongs to the family solanaceae and is known as ‘indian ginseng’ in the traditional system of medicine. objectives: in the present investigation, comparative analysis was carried out between two different ecotypes of w. somnifera related to total soluble protein and antioxidant enzyme activity [catalase (cat), superoxide dismutase (sod) an...

Solanum melongena fruit juice contains peroxidase activity of the order of 0.125 IU/mL. A method for the 11-fold purification of the enzyme was developed. The Km values of the peroxidase for the substrates guaiacol and hydrogen peroxide were 6.5 mM and 0.33 mM, respectively. The pH and temperature optima were 5.5 and 84 degrees C, respectively using guaiacol as the substrate. Sodium azide and p...

In this study, boroxine derivative (K₂[B₃O₃F₄OH]) was tested as an inhibitor of horseradish peroxidase (HRP) by spectrophotometric and electrochemical methods. The activity of horseradish peroxidase was first studied under steady-state kinetic conditions by a spectrophotometric method which required the use of guaiacol as a second substrate to measure guaiacol peroxidation. The results of this ...

Peroxidase activities of autonomously functioning thyroid tumors (T) and surrounding non-tumorous tissue (N) in 5 patients were determined by employing guaiacol or iodide as the second substrates. The mean values for specific activities of T were 30 times (in iodide oxidation assay) or 4 times (in guaiacol oxidation assay) as high as those in N, being significantly higher than those of non-func...

Environmental pollution has been a serious problem since the start of the industrial revolution. The pollution usually comes from industrial wastes, waste water, heavy metal, etc. Heavy metals such as lead, mercury, tin are considered to be toxic to living organisms and enzyme activities. However, metal ions can play essential role in plants and animals as they are involved in fundamental proce...