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Polyphenolic compounds and antioxidant activity in eggplants (Solanum melongena L.) seem to depend on cultivar, maturity stage, environmental conditions and the part of the fruit. In this work, the polyphenolic content and antioxidant activity of pulp, whole fruit and peel from fresh dark-purple and white eggplant varieties cultivated in Southern Algeria were measured. Total phenolic content were determined by Folin-Ciocalteu test, and antioxidant activity measured using cyclic voltammetry. Correlations between antioxidant activity and total phenolic content were also examined. Within each cultivar, the total phenolic content and antioxidant activity were highest in the peels, followed by the whole fruit and the pulp. In the peel, whole fruit and pulp the dark-purple eggplant had the highest total phenolic contents and the highest total antioxidant activities.

Spectrophotometrical technics based assay were developed for the calculation of binding parameters like binding constant, ratio of binding constants and binding free energy of two potential antioxidants 2-(ferrocenylmethylamino)benzonitrile (2FMAB) and 3-(ferrocenylmethylamino)benzonitrile (3FMAB) with 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH). 3FMBA shows highest binding constant and highest binding free energy (2.28×10-5 M-1) and (30.06 KJmol-1) respectively. Binding free energy of DPPH-3FMAB is three times greater than that of the standard antioxidant ascorbic acid (10.93 KJmol-1).

In the present work the oxidation of ferrocene, , to the ferrocenium cation, , was examined in the solvents dichloromethane, and aqueous ethanol using the technique of cyclic voltammetry. The anodic (Epa) and the cathodic (Epc) peak potentials, as well as the corresponding anodic (ipa) and cathodic (ipc) peak currents, were obtained at different scan rates (0.05, 0.10, 0.30, 0.50 V.s-1). The diffusion coefficients (D) have been calculated using the Randles-Sevcik equation. The effects of changing the scan rate on the electrochemical behavior of ferrocene have been examined.

The oxidative electrochemistry of N'-Ferrocenylmethyl-N'-Phenylbenzohydrazide FcX was studied in acetonitrile with tetrabutylammonium hexafluorophosphate as the supporting electrolyte and aqueous ethanol using the electrochemical technique. This study using cyclic (CV) and rotating disk electrode (RDE) voltammetry showed that the FcX/FcX+ redox couple is reversible in this electrolytes. The effects of changing the scan rate on the electrochemical behavior of ferrocene have been examined. A comparison of the electrochemical behavior of ferrocene and N'-Ferrocenylmethyl-N'-Phenylbenzohydrazid have been examined.

In this work, we studied the efficiency of corrosion inhibition of carbon steel XC70 in H2SO4 0.5 M aqueous solution using ferrocenyl derivatives synthesized in our laboratory, this compound is: 3-(ferrocenylmethylamine)benzonitrile. The inhibitory potential of this compound was determined by electrochemical techniques based on Tafel segments. The results show that the studied compound has an efficiency of inhibition which depends on its concentration. The adsorption of these compounds on the surface of the metal is a chemical adsorption. The inhibition of corrosion reached 84 % at a concentration of 50 ppm.

The present work is to develop software to predict the value yield and the distribution coefficient in the process of liquid-liquid extraction of components of a mixture, from mathematical models expressing these entities, based on equations equilibrium between liquid-liquid phases, and predict the conditions under which the extraction operation is favorable, unfavorable or impossible to realize, by studying the variation of the entities cited, based on the parameters influencing the extraction, which are: initial concentrations, rate of solvent and pH, in the case of a simple extraction (extraction of neutral products) or when it is reactive (extraction of complex acids or bases) for one or more components.The programming language used is "Delphi" which is a very powerful oriented object programming under Windows.

In this study the antioxidant capacity of ethanolic EE and water WE extracts from different parts (calyx, peel, and pulp) of eggplant (Solanum melongena L) were evaluated using cyclic voltammetry. The antioxidant capacity of different parts of eggplant was measured using ascorbic acid equivalent antioxidant capacity assays. The peel extracts of both dark purple and white samples showed the highest antioxidant capacity (66.78 and 75.62 mg/g) followed by pulp (16.54 and 30.56 mg/g), and calyx (14.82 and 21.27 mg/g). These results indicate that antioxidant capacity of eggplant varied by parts and solvents.

The aim of this study was to assess the nutritional compositionand antioxidant activity of bee pollen produced in the North western region of Algeria.The content of total phenolic compounds,flavonoids, and antioxidant activity using the molybdate ion reductionmethod were determined. The meancontents of phenolic compounds and total flavonoids were 30.46 ± 8.22 mgof GAE.g–1 pollen and 8.92 ± 5.5 mg of RE.g–1 pollen, respectively. Highantioxidant activities were found for the molybdate ion reductionmethod, with values that ranged from 71.95 to 101.5μg of GAE.g–1 pollen. The bee pollen ofBoufarikshowed high antioxidant activity probably due to the high contentof phenolic compounds present in pollen.

The aim of the present study was to evaluate the physical and chemical properties of five Algerian unifloral types of honey. Several physical parameters of honey, such as pH, moisture content, electrical conductivity, total dissolved solids, color intensity and total sugar content, were measured. The mean pH, moisture content, EC and water insoluble solids of Algerian honey were 4.41± 0.58, 15.3 ± 1.5%, 0.324± 0.116 mS/cm and 0.141± 0.065%, respectively. The mean color was 81 ± 72 mm Pfund. The majority of honey samples test results (moisture content, electric conductivity and acidity) levels were within the acceptable range of world honey standards.

In this work we present a theoretical approach for the determination of octanol/water partition coefficient of selected ferrocenes bearing different substituents, the calculation is based on the adaptation of the Rekker method. Our prediction of obtained theoretical partition coefficients values of logP for all studied substituted ferrocene was confirmed by comparison with known experimental values obtained mainly from literature. The results obtained show that calculated partition coefficients are in good agreement with experimental values. For estimation of the octanol/water partition coefficients of the selected compounds, the average absolute error of log P is 0.13, and The correlation coefficient is R2 = 0.966.

In this work, we studied the efficacy of corrosion inhibition of carbon steel X70 in HCl 1M solution using ferrocenyl compounds prepared in VPRS laboratory, these compounds are: N-(férrocenyl méthyl)-2-nitro aniline(Fc12), N-(férrocenyl méthyl)-3-nitro aniline(Fc13) and N-(férrocenyl méthyl)-4-nitro aniline(Fc14).The inhibitory potency of these compounds was determined by the electrochemical impedance spectroscopy (EIS). The overall results show that these compounds have varying percentages of inhibition. The adsorption of these compounds on the surface of the metal is a chemical adsorption.In HCl 1M, the compound Fc12 had the best ability of inhibition at a concentration of 70ppm (R = 91.24%).

A simple sensitive square wave voltammetric method for the determination of lead contamination of several kohl samples purchased from Algeria retail stores was developed using glassy carbon electrode. The peak current response of 5 standards aqueous solution of lead in NaNO3 as supporting electrolyte was observed showing a linear calibration curve in the concentration range of 4×10-3 – 2.5×10-4 mol/l of lead. Over this concentration range, the equation obtained from the linear calibration graph for lead is Y = 0.00068 + 0.0093x with a correlation coefficient of r2 = 0.987. Following this step, the potential of an aqueous solution of 12 kohl samples containing 2 M nitric acid solution as supporting electrolyte is then swept in the same range of potential (-400 to -700 mV). The amount of lead is then deduced using the linear calibration graph for lead. The results showed up to 52.14% of lead present in kohl, this concentration was over the safe limits of lead set by the world health organization standards. However; only five commercial samples of kohl tested contained less than 0.001% lead. Complete recovery of lead from the kohl was obtained by simple nitric acid digestion.

The aim of the present study was to evaluate the physical and chemical properties of five Algerian unifloral types of honey. Several physical parameters of honey, such as pH, moisture content, electrical conductivity, total dissolved solids, color intensity and total sugar content, were measured. The mean pH, moisture content, EC and water insoluble solids of Algerian honey were 4.41± 0.58, 15.3 ± 1.5%, 0.324± 0.116 mS/cm and 0.141± 0.065%, respectively. The mean color was 81 ± 72 mm Pfund. The majority of honey samples test results (moisture content, electric conductivity and acidity) levels were within the acceptable range of world honey standards.

The antioxidant of ethanolic extract of two species of Origanum and essential oil of plant Origanum vulgare were investigated and also the total phenolic and flavonoid content measured. The radical scavenging activity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Total phenolic and flavonoid contents were estimated by Folin-Ciocalteu and aluminum chloride methods, respectively. According to the results the leaves extracts have very important values for polyphenols (266.86 mg GAE / g and 194.78 mg GAE / g) and high antioxidant activity; DPPH (IC50 = 1.37 g / l and IC50 = 1.53mg / l ) for species majorana, and vulgare respectively; also the DPPH of essential oil of Origanum vulgare was IC50 = 15.360 mg/l . This data suggest of these extracts as a natural source of phenolic compounds and antioxidant.

In this work, we studied the efficiency of corrosion inhibition of carbon steel XC70 in H2SO4 0.5 M aqueous solution using ferrocenyl derivatives synthesized in our laboratory, this compound is: 3-(ferrocenylmethylamine)benzonitrile. The inhibitory potential of this compound was determined by electrochemical techniques based on Tafel segments. The results show that the studied compound has an efficiency of inhibition which depends on its concentration. The adsorption of these compounds on the surface of the metal is a chemical adsorption. The inhibition of corrosion reached 84 % at a concentration of 50 ppm.

The aim of this study was to assess the nutritional composition and antioxidant activity of bee pollen produced in the North western region of Algeria. The content of total phenolic compounds, flavonoids, and antioxidant activity using the molybdate ion reduction method were determined. The mean contents of phenolic compounds and total flavonoids were 30.46 ± 8.22 mg of GAE.g–1 pollen and 8.92 ± 5.5 mg of RE.g–1 pollen, respectively. High antioxidant activities were found for the molybdate ion reduction method, with values that ranged from 71.95 to 101.5 μg of GAE.g–1 pollen. The bee pollen of Boufarik showed high antioxidant activity probably due to the high content of phenolic compounds present in pollen.

In this study the antioxidant capacity of ethanolic EE and water WE extracts from different parts (calyx, peel, and pulp) of eggplant (Solanum melongena L) were evaluated using cyclic voltammetry. The antioxidant capacity of different parts of eggplant was measured using ascorbic acid equivalent antioxidant capacity assays. The peel extracts of both dark purple and white samples showed the highest antioxidant capacity (66.78 and 75.62 mg/g) followed by pulp (16.54 and 30.56 mg/g), and calyx (14.82 and 21.27 mg/g). These results indicate that antioxidant capacity of eggplant varied by parts and solvents.