this study, the effects of a number commonly used pesticides on activity polyphenol oxidase (PPO) enzyme from pesticide-free and pesticide-applied 'Jonagold' apples were comparatively evaluated. Substrates 4-methylcatechol, pyrocatechol, pyrogallol L-tyrosine to determine substrate specificity PPO obtained apple. According results, contrary, apple did not show any against which is monophenolic ...

OBJECTIVES Most clinical laboratories replaced their manual precipitation techniques for the determination of urinary protein with automated dye binding assays or benzethonium chloride-turbidimetric assays. Few studies have validated these assays for the measurement of urinary proteins in the normal range. DESIGN AND METHODS This study compares four automated assays for the measurement of uri...

Electrogenerated chemiluminescence (ECL) of CdSe quantum dots (QDs) dispersed in aqueous solution was studied with bare electrode. The ECL emission was observed at -1.4 V vs. Ag/AgCl and the ECL spectrum peak is similar to that of the defect photoluminescence (PL) spectrum, indicating the surface defects played a critical role in the emission process. The experiment results suggested that disso...

Discs of network polyvinyl alcohol-glutaraldehyde (PVAG) were synthesized and coated with polyaniline (PANI) using glutaraldehyde as a chemical arm (PVAG-PANIG-HRP disc). The best conditions for the immobilization were established as about 1.0 mg mL(-1) of protein, for 60 min and pH 5.5. The soluble enzyme lost all of its activity after incubation at 70°C for 15 min, whereas the PVAG-PANIG-HRP ...

The glycine betaine (betaine), interacts with several types of proteins with diverse structures in vivo, and in the contact regions, the aromatic rings of protein residues are frequently found beside the trimethylammonium group of betaine, implying the importance of the cation−π interactions in recognition of this molecule. The crystal structures determined by X-ray crystallography of the compl...

The encapsulation of chloroperoxidase from Caldariomyces fumago (CPO) in block copolymer polymersomes is reported. Fluorescence and electron microscopy show that when the encapsulating conditions favour self-assembly of the block copolymer, the enzyme is incorporated with concentrations that are 50 times higher than the enzyme concentration before encapsulation. The oxidation of two substrates ...

This work deals with the use of pruning ANNs in conjunction with genetic algorithms for resolving nonlinear multicomponent systems based on oscillating chemical reactions. The singular analytical response provides by this chemical system after its perturbation was tted to a gaussian curve by least-square regression and the estimates were used as inputs to the ANNs. The proposed methodology was ...

Atmospheric conditions, as well pollutants, can induce changes in the viability and germinability of pollen grain. This process frequently occurs cities due to high rate air pollution that alter quality pollen, affecting its biological functions. In this work, effect different environmental stress factors, mainly UV-B radiation polluting gases (CO, NO2 SO2), on maturity four ornamental tree-spe...

18O labeling studies on the catechol 1,2-dioxygenase-catalyzed oxidative cleavage of pyrogallol demonstrate that the enzyme functions both as a dioxygenase and a monooxygenase in this reaction. Two products are observed, 2-pyrone-6-carboxylic acid, 99% singly labeled at the carboxylate, and 2-hydroxy-cis,cis-muconic acid, 74% doubly labeled (one 18O at each carboxylate) and 24% single labeled (...