Phenolic compounds were measured in leaf tissues of apple cvs Jonagold and Golden Delicious, healthy and infected by Venturia inaequalis. Leaves were sampled from May to September 2005 and analyzed by high performance liquid chromatography. Hydroxycinnamic acids detected were chlorogenic, caffeic, ferulic and pcoumaric. In addition, the presence was ascertained of the dihydrochalcone phloridzin...

free radicals involved in a number of diseases due to the oxidative damage to dna, lipids, and proteins and which can result in failure of cellular functions. dried plant bulbs and leaves methanolic and ethanolic extracts were prepared. total antioxidant activities of the methanolic extracts of romulea ramiflora and gagea fibrosa were determined using β-caroten-linoleic acid assay. romulea-bulb...

A method for the colorimetric estimation of manganese by reduction of the phosphomolybdicphosphotungstic acid phenol reagent has been described (Abul-Fadl, 1948). Cobalt was also found to give a similar colour reaction in the presence (but not in the absence) of amino-acids. Conversion of cobalt into the cobaltinitrite did not affect its response to this reaction. As methods for the estimation ...

the green synthesis of metallic nanoparticles is an active research area in nanotechnology. in the present study, antioxidant potential, total reducing capacity and silver nanoparticles (ag nps) synthetic potential of methanolic leaf extracts of seven plant species were evaluated and compared. antioxidant capacity, expressed as µmol trolox equivalents g-1 dw (µmol te g-1 dw), ranged from 116.0 ...

In the calorimetric methods for the determination of tyrosine and tryptophane, described by Folin and Ciocalteu (1) in 1927, 1 or 2 gm. of protein material are taken for the preliminary hydrolysis. It has seemed desirable to try to adapt these methods to the use of smaller amounts of material (0.1 gm.) in order to broaden the applicability of the methods. While this work was in progress, there ...

Methods available for the measurement of antioxidant capacity are reviewed, presenting the general chemistry underlying the assays, the types of molecules detected, and the most important advantages and shortcomings of each method. This overview provides a basis and rationale for developing standardized antioxidant capacity methods for the food, nutraceutical, and dietary supplement industries....

The main objective of this study was the screening of some selected aromatic plants very popular in Greece, with respect to their total phenolic content, antioxidant capacity, reducing activity, and oxidative stability. All plants were extracted with the conventional method, reflux with methanol. The essential oils of the plants were also analyzed for their antioxidant properties. The total phe...