All aerobic biological systems, including N(2)-fixing root nodules, are subject to O(2) toxicity that results from the formation of reactive intermediates such as H(2)O(2) and free radicals of O(2). H(2)O(2) may be removed from root nodules in a series of enzymic reactions involving ascorbate peroxidase, dehydroascorbate reductase, and glutathione reductase. We confirm here the presence of thes...

Inhibition of manganese peroxidase by cadmium was studied under steady-state and transient-state kinetic conditions. CdII is a reversible competitive inhibitor of MnII in the steady state with Ki approximately 10 microM. CdII also inhibits enzyme-generated MnIII-chelate-mediated oxidation of 2,6-dimethoxyphenol with Ki approximately 4 microM. CdII does not inhibit direct oxidation of phenols su...

BACKGROUND 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 Kine...

The Alicyclobacillus species, which are spore-forming acidophil bacilli, remain in fruit juices, survive through usual sterilizing conditions for acidic beverages, and may cause deterioration. A. acidoterrestris has a D95°C value of 5.3 min, a growth pH range of 2.5 to 5.5, and a growth temperature range of 20°C to 55°C. A major consequence of deterioration in fruit juice is production of guaia...

To assess nickel-induced toxicity in plants, Zea mays seeds were germinated and cultured on nutrient solution with nickel concentrations of 50-200 μM for a period of two weeks. Observed biological makers included biomass, soluble and total protein contents, and the activities of guaiacol peroxidase (GPX), ascorbate peroxidase (APX), catalase (CAT), and phenylalanine ammonia-lyase (PAL) in the l...

Superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and the comet assay (SCGE) were used as biomarkers to evaluate the oxidative stress and genotoxicity of toluene, ethylbenzene and xylene in earthworms (Eisenia fetida). The results indicated that the exposure of the three pollutants caused a stress response of the three enzymes, an approximate bell-shaped change (a tendency ...

The antifungal efficacy of seed extracts (propanol, ethanol, methanol and sterile deionised water) of Camelina sativa cv. Calena (EC643910) against Rhizopus stolonifer was investigated by agar disc diffusion method. Among all extracts, methanolic seed extract (Disc 3) showed significant activity against R. stolonifer. However, no activity was observed against rest of the extracts (Disc 1, 2 and...

To investigate the effects of Cd on tolerance and antioxidant activities of castor, two different castor (Ricinus communis L.) cultivars (Zibo No. 5 and Zibo No. 8) were used for a hydroponic experiment (0, 1 and 2mg/L Cd) and a pot experiment using Cd-contaminated soil (34mg/kg) with the addition of ethylenedinitrilotetraacetic acid (EDTA). The results indicated that there were significant dif...

abstract pythium aphanidermatum is one of the most important agent of root and foot rot of cucumber, particularly in the warm humid climate. induction of host resistance by microorganisms or by the synthetic compounds is recently considered as one of the biological control method of disease. trichoderma harzianum bi is a good candidate for induction of resistance in plant against diseases. the ...