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Anticoagulant Activity of Some Ficus carica Varieties Extracts Grown in Algeria

Abstract

The hemostatic system is a complex balanced system that triggers clot formation to prevent blood loss after trauma. To block abnormal bleeding and maintain intravascular blood in a liquid state, in this study we investigated the possible anticoagulant effect of leaves and fruits extracts from some fig varieties grown in Algeria by determining the quick time (QT). The blood samples of the healthy individuals were used. For in vitro coagulation assays, the clotting times obtained in the presence of polyphenols in different extracts of F.carica samples indicate that they exert a high anticoagulant activity on the exogenous pathway of coagulation. Moreover, the polyphenolic extract of ‘Roudane’ variety presented a substantial increase in coagulation. Based on these preliminary results, it can be suggested that the fig polyphenolic extracts (FPE) of this varieties have anticoagulant activity that could be useful in preventing blood clots.

Open access
Assessment of Antioxidant effect of the essential oil and methanol extract of Centaurea dimorpha Viv. aerial parts from Algeria.

Abstract

The essential oils obtained by hydrodistillation of aerial parts of Centaurea dimorpha Viv. were analyzed by means of gas chromatography-mass spectrometry (GC-MS). The main constituents were Caryophyllene oxide (09.88%), limonene (5.73%), tetradecanoic acid (5.68%), spathulenol (5.44%), methyl hexadecanoate (4.45%), and α-pinene (03.08%). To our best knowledge this is the first study of essential oils from the aerial parts of Centaurea dimorpha growing in Algeria. Moreover the essential oil and methanolic extract were screened for their possible in vitro antioxidant activity by DPPH free radical-scavenging test. The findings showed that the percentage inhibition is 10.67 and 77.01 respectively at a concentration of 1mole/L.

Open access
Comparative Study of the Bacteriological Activity of Zinc Oxide and Copper Oxide Nanoparticles

Abstract

Interest in nanomaterials, especially metal oxides, in the fight against resistant and constantly changing bacterial strains, is more and more expressed. Their very high reactivity, resulting from their large surface area, promoted them to the rank of potential successors of antibiotics.

Our work consisted of the synthesis of zinc oxide (ZnO) and copper oxide (CuO) in the nanoparticle state and the study of their bactericidal effect on various Gram-negative and Gram-positive bacterial strains.

The nanoparticles of metal oxides have been synthesized by sol-gel method. Qualitative analysis and characterization by UV / Visible and infrared spectrophotometry and X-ray diffraction confirmed that the synthetic products are crystalline. The application of the Scherrer equation allows to determine the size of the two metal oxides, namely: 76.94 nm for ZnO and 24.86 nm for CuO.

The bactericidal effect of ZnO and CuO nanoparticles was tested on Gram-positive bacteria (Staphylococcus aureus, Staphylococcus hominis, Staphylococcus haemolyticus, Enterococcus facials) and Gram-negative bacteria (Escherichia coli, Schigella, Klepsiella pneumoniae and Pseudomonas aeruginosa). The results indicate that the tested metal oxides nanoparticles have an effect that varies depending on bacterial species. Indeed, Gram-positive bacteria show greater sensitivity to ZnO nanoparticles whereas Gram-negative bacteria are more sensitive to CuO nanoparticles.

Open access
Design of Dye-Sensitized Solar triphenodioxazine using TiO2 as a semiconductor

Abstract

The present work deals with the synthesis of multichromophores which strongly absorb the solar spectrum to functionalize the nanoparticle oxide semiconductor used in the hybrid cells. At first, we developed a material that forms a chromophore triphenodioxazine. We obtained some triphenodioxazines with high yields up to 70 percent. On the other hand, we have carried out many tests such as UV-Visible, Cyclic voltammetry for our molecules to check their electronic and optical properties. The results confirmed that these chromophores meet the criteria for use in photovoltaic cells. Finally, we have successfully realized photovoltaic cells with triphenodioxazine. The findings were very interesting since the photovoltaic conversion efficiencies ranged from 4.30% to 6.30%. The new synthesis strategy of these chromophores opens a way for the development of organic materials used for photovoltaics.

Open access
Experimental setup for light-to-heat NIR conversion measurements of gold nanoparticle solutions

Abstract

In recent years, there is a constantly increasing interest in the application of nanoparticles for cancer diagnosis and cancer therapy. In this respect, the most promising nano-objects at present are the gold nanoparticles. A very convenient and powerful property of these objects is their ability to increase their temperature under electro-magnetic irradiation with certain wavelength. In our research we have directed our efforts toward particular nano-objects specifically sensitive to electromagnetic radiation in the near-infrared region (NIR). In order to study the photothermic properties of the solutions of gold nanoparticles in the NIR we constructed a specific electronic setup consisting of a laser system with interchangeable laser diodes with different wavelength NIR light, a thermally-insulated cuvette-holder compartment with temperature measuring probes and a NIR spectrometer to control the stimulated fluorescence emission of the nanoparticle solutions. The temperature measurement compartment with the thermal-insulated cuvette holder was designed to maintain the solutions’ temperature at a fixed value right before the moment of laser irradiation. To maintain the measurement setup at a fixed temperature before the irradiation we used a thermal stabilized system based on two Peltier cells with electronic temperature control. The temperatures of the ambient air and the temperature of the cuvette walls were continuously measured in order to make corrections about the temperature dissipation during the irradiation.

Open access
HPLC-DAD profiling and antioxidant activity of the n-butanol extract from aerial parts of Algerian Crithmum maritimum L.

Abstract

In this study, phenolic compounds from Crithmum maritimum L. n-butanol soluble fraction were quantified and identified spectrophotometrically and by using HPLC-DAD technics. They equally investigated for their antioxidant potential utilizing six in vitro assays: DPPH, ABTS•+, O2 •−, Bleaching of β-carotene in linoleic acid, CUPRAC and Ferric reducing power. High amounts of total phenolics and flavonoids were recorded: 161.57± 0.479 μg GAeq.mg−1 and 31.56± 0.291 μg Qeq.mg−1 respectively. Nine compounds among them hydroxicinnamic acid and hydroxybenzoic acid derivatives, coumarins and flavonoids were identified. Chlorogenic acid known for their various pharmacological properties was detected as major compound of the extract. Rutin, vanillin, trans-2-hydroxycinnamic acid, ellagic acid, ferrulic acid, 6,7 dihydroxy coumarin, methyl 1,4 benzoquinone and trans-cinnamic acid were also detected. The extract was found to exhibit strong antioxidant capacities in all systems. Based on these results, it is right to conclude the n-butanol extract is promising source of natural antioxidants.

Open access
In-vivo Antidiarrhoeal and anti-ulcerative activities of the Tetraclinis articulata species of the Cupressaceae family

Abstract

Tetraclinis articulata (Thuya of Barbary), endemic to North Africa, is used as a traditional medicine for the treatment of many diseases [1]. We investigated the antidiarrhoel properties of the butanol extract of Tetraclinis articulata (BETA) in male and female Swiss albino mice to support its traditional use. The antidiarrhoeal activity of the plant extract was evaluated in a model of castor oil-induced diarrhoea model in mice and compared to loperamide (a reference inhibitor of diarrhoea). The effect of (BETA) on gastrointestinal motility was determined by the oral administration of charcoal and Castrol oil-induced intestinal fluid accumulation (enteropooling).The (BETA) showed remarkable antidiarrhoeal activity significantly inhibited gastrointestinal motility and castor oil induced enteropolysis (68,18%), more than to the inhibition achieved in loperamide treated mice (60,16%). The second aim of the present study was to evaluate the anti-ulcerative activity of The (BETA), it produced percent protection of control colitis by 77, 40%, while the standard drug (aspirin) produced 81,39% protection. We conclude that Tetraclinis articulata extracts are potential sources of new anti-ulcer agents and antidiarrhoeal drugs.

Open access
Interaction of 1,2-alkadienephosphonates with propargyl alcohole

Abstract

The reactivity of 1,2-alkadienephosphonates in nucleophilic addition reactions has been investigated.

Open access