In-Vitro Antioxidant Activity and Total Phenolic Content of Ruta montana L. Extracts

The aim of this study is to evaluate in vitro antioxidant activities of Ruta montana L.  extracts. This activity was evaluated by three methods : DPPH (2, 2'-diphenyl- 1- picrylhydrazy), bleaching of β-carotene and chelation of ferrous iron. Results showed that ethyl acetate extract (EAE) represents the highest amount of total polyphenols, tannins and flavonoids with 257,1 ± 0,703µg gallic acid equivalent/mg of extract,  251 ± 1.41 µg tannic acid equivalent /mg of extract,117,4 ± 3,451 µg quercetin equivalents/mg of extract, 139,5 ± 4,107 µg rutin equivalents/mg of extract, respectively. In the DPPH assay, ethyl acetate extract showed the higher scavenging capacity (IC50 = 0.044 ± 0.001 mg/ml) followed by methanol, aqueous and chloroform extract. Whereas, AqE showed the best chelating effect and the best inhibitory capacity of the coupled oxidation of linoleic acid/ β-carotene. Keywords: Ruta montana L; polyphenols; antioxidant activity; free radical scavenging

Antioxidant Activity of Centaurium erythraea Extracts

Phototherapy has known a great evolution all the world and some medicinal plants are importance remedies of some diseases. Centaurium erythraea is one of the medicinal plants widely used in this field. In this study, we have evaluated the total polyphenolic and the flavonoid contents of the methanolic (ME) and aqueous (AqE) extracts of the plant Centaurium erythraea as well as its antioxidant activity using the DPPH (2'2-diphenylpicrylhydrazyl), β-carotene /linoleic acid bleaching and reducing power assays. The total polyphenolic content of the methanolic extract was 35,45± 0,041 μg AGE/mg extract and flavonoids was 6,65 ± 0,060 μg QE/mg. The total polyphenolic content of the aqueous extract was 54,27 ± 0,023 μg AGE/mg extract and flavonoids was 3,275 ± 0,003 μg QE/mg. The results of the DPPH test showed a powerful antioxidant activity with a very similar IC50 for the methanolic (IC50=0.232 ± 0.002mg/ml) and aqueous (0.208 ± 0.002mg/ml) extracts. The inhibitory activity of the tow extracts in the β-carotene/linoleic acid assay was (86.781 ± 0.17%) for the methanolic extract and (77.816 ± 0.69%) for the aqueous extract. ME has the higher reducing power (IC50 = 0.35 ± 0.066 mg / ml) compared to the AqE (IC50 = 1.31 ± 0.047 mg / ml). Keywords: Centaurium erythraea, antioxidant activity, polyphenols, DPPH scavenging, β-carotene, reducing power

Polyphenols contents and antioxidant Activity of extracts from Leaves and flowers of Thymelaea hirsuta

Thymelaea hirsuta  is a medicinal plant, belonging to the genus Thymelaea (Thymelaeaceae) widely used in Mediterranean countries especially in Algeria. In this study, we have evaluated the total polyphenols and flavonoids contents of methanolic and aqueous extracts of Leaves and flowers of Thymelaea hirsuta as well as its antioxidant activity using the DPPH (2'2-diphenylpicrylhydrazyl) and β-carotene /linoleic acid bleaching assays. The yield of the methanolic and aqueous extract was 11, 55% and 13, 25% respectively. The total polyphenols content of the methanolic extract was 295, 22 µg GAE/ mg extract and flavonoids was 09, 40 µg QE/mg and 26, 42 µg RE/ mg extract. The total polyphenols content of the aqueous extract was 57, 95 µg GAE/ mg extract and flavonoids was 4.59 µg QE/ mg and 10.66 µg RE/ mg extract. In the DPPH assay, methanolic extract showed the higher scavenging capacity (IC50 = 0.03 ± 0.004 mg/ml), followed by aqueous extract with IC50 of 0.275 ± 0.019 mg/ml. In the test of β-carotene /linoleic acid, the percentage of inhibition was 39.1±1.33% for the aqueous extract and 41.05±2.72% for methanolic extract. Keywords: Thymelaea hirsuta, antioxidant activity, polyphenols, DPPH scavenging, β-carotene

Resonance fluorescence revival in a voltage-controlled semiconductor quantum dot

We demonstrate systematic resonance fluorescence recovery with near-unity emission efficiency in single quantum dots embedded in a charge-tunable device in a wave-guiding geometry. The quantum dot charge state is controlled by a gate voltage, through carrier tunneling from a close-lying Fermi sea, stabilizing the resonantly photocreated electron-hole pair. The electric field cancels out the charging/discharging mechanisms from nearby traps toward the quantum dots, responsible for the usually observed inhibition of the resonant fluorescence. Fourier transform spectroscopy as a function of the applied voltage shows a strong increase of the coherence time though not reaching the radiative limit. These charge controlled quantum dots act as quasi-perfect deterministic single-photon emitters, with one laser pulse converted into one emitted single photon

Acute and Sub-acute Toxic Effects of Algerian Peganum harmala L. Crud Extract

The present study was carried out to evaluate the acute and sub-acute toxicity of Algerian Peganum harmala L. seeds (Zygophyllaceae). For the acute toxicity assessment, oral administration of P. harmala crud extract to mice in single doses of 0-12 g/kg caused dose-dependent general behavior adverse effects and mortality with LD50 of 2,86 g/kg. In the sub-acute study, daily oral administration of the crude aqueous extract for 28 consecutive days did not result no mortality. However, our results showed a significant difference in organs weights between control and treated animals. In the biochemical analysis, significant changes occurred in Bilirubin, uric acid (UA) and alkaline phosphatase (ALP) in the treated animals when compared to the control ones. Hematological analysis showed differences in WBC count and Hemoglobin estimation. However, urinalysis was negative for all parameters except Glucose in the treated group. Pathologically, a few gross abnormalities and histological changes were observed in hepatic and nephritic tissues. Keywords: Peganum harmala L., Acute and Sub-Acute Toxicity, Hematological parameters, Biochemical parameter

Acute Toxicity Study of Aqueous Extracts of Thymelaea hirsuta Leaves And Flowers in Rabbits

Thymelaea hirsuta is a medicinal plant known for its therapeutic virtues in traditional medicine. The objective of this study was to evaluate the acute toxicity of aqueous extract of leaves and flowers of Thymelaea hirsuta in rabbit. Aqueous extract was administered to rabbit in single doses of 2.5, 4, 5.5 and 7 g/kg given by gavage. General behavior, adverse effects and mortality were determined for up to 7 days. Biochemical parameters aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), cholesterol (CHOL) and glucose (GLU) were determined after 7 days. The results showed no mortality was observed during the 7 days of the observation period, an increase in AST and  ALT in treated groups at the doses of 4, 5.5 and 7 g/kg, and a decrease in both cholesterol and glucose levels in treated groups compared to control. Keywords: Thymelaea hirsuta, Acute toxicity, Biochemical parameters, adverses effects

Passive harmonic mode-locking by mode selection in Fabry-Perot diode lasers with patterned effective index

We demonstrate passive harmonic mode-locking of a quantum well laser diode designed to support a discrete comb of Fabry-Perot modes. Spectral filtering of the mode spectrum was achieved using a non-periodic patterning of the cavity effective index. By selecting six modes spaced at twice the fundamental mode spacing, near-transform limited pulsed output with 2 ps pulse duration was obtained at a repetition rate of 100 GHz.Comment: 3 page

Agent-based self-management of MPLS DiffServ-TE domain

MPLS DiffServ-TE presents the solution awaited so much by the network service providers by allowing a differentiation of services and a traffic engineering based on a fast packet switching technology. However, the management of such a network is not a simple function and could not be done manually. In this paper, we propose a novel architecture based on the Multi-Agent Systems (MAS) capable of managing automatically MPLS DiffServ-TE domains. Based on the network states, our intelligent agents take the appropriate decisions. They, for example, reconfigure the network accordingly5th IFIP International Conference on Network Control & Engineering for QoS, Security and MobilityRed de Universidades con Carreras en Informática (RedUNCI