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

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

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

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

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

PHYTOCHEMICAL PROFILES, ANTIOXIDANT CAPACITY AND PROTECTIVE EFFECT AGAINST AAPH-INDUCED MOUSE ERYTHROCYTE DAMAGE BY DAPHNE GNIDIUM L. SHOOTS EXTRACTS

Objective: Various biological activities have been reported for Daphne gnidium, the aim of the present study was to determine polyphenols and some biological activities of extracts from the shoots of this plants.Methods: Phenolic and flavonoids contents of D. gnidium extracts (DGE) were determined by Folin-Ciocalteau and identified by HPLC–DAD/MS. Free radical scavenging and antioxidant potential of the crude (CE), chloroform (CHE) and ethyl acetate (EAE) extracts of D. gnidium shoots were investigated using several in vitro and ex vivo assays, including 2, 2-diphenyl-picrylhydrazyl radical scavenging, superoxide anion scavenging (by both enzymatic and nonenzymatic methods) and hydroxyl radical scavenging capacity methods. The antioxidant activity of the extracts was measured using the xanthine oxidase (XO) inhibitory activity, reducing power and ß-carotene-linoleic bleaching assays. Inhibition of lipid peroxidation and oxidative hemolysis were also performed to confirm the protective effect of these extracts.Results: It was found that values of phenolics varied between 130.84±5.99 and 137±7.66 mg gallic acid equivalent/g dry extract. HPLC analysis revealed the presence of cinnamic acid derivatives and other metabolites from the flavonoids family. All extracts exhibited a superoxide scavenging capacity. The EAE had the highest antioxidant activity as measured by DPPH radical and hydroxyl radical scavenging activity. The extracts showed an inhibitory effect on xanthine oxidase, the IC50 rangesfrom 0.021±0.001 to 0.061±0.001 mg/ml. The EAE showed also potent reducing power ability. CHE possess an inhibition ratio of (92.11%) in the linoleic acid oxidation assay close to that of BHT (96.77%). All extracts exhibited antioxidant activity in the linoleic acid emulsion system (3.87-61.11 %). Under the oxidative action of AAPH, EAE and CE showed higher protective effect against erythrocytes hemolysis than the CHE. The percentage of hemolysis (H%) determined for EAE and CE after 1 h of incubation were 0% and 1.9%, respectively.Conclusion: This study indicates that DGE contains relevant antioxidant compounds responsible, at least in part, for its antioxidant and radicals scavenging activity. Flavone derivatives were determined as the main active component of the shoots part and the CHE was the most active extract.Â

In vitro antioxidant activity and gastroprotective effect of ethanolic extract from Cucumis melo L. var. inodorus fruit on ethanol-induced gastric ulcer in rats

The aim of this study was to estimate the content of polyphenols, flavonoids and tannins and to evaluate the antioxidant property and the antiulcer activity of the ethanolic extract of melon (Cucumis melo L. var. inodorus) pulp on ethanol-induced gastric ulcers in rats.  Ferric reducing power and hydroxyl radical scavenging tests were applied to evaluate the in vitro antioxidant activity. The polyphenolic and flavonoids contents of    melon extract were found to be 56.5 ± 2.49 mg GAE/g of dry extract and 0.43 ± 0.09 mg QE/ g of dry extract, respectively. Whereas the tannins content was 48. 30 ±  0. 9 mg ETA/ g of dry extract.  Melon pulp  extract exhibited  a good reducing potential   with  an  EC50 of  4.23 ± 0.08 mg/ml and high hydroxyl radical scavenging activity with IC50 of  1.83± 0.09 mg/ml. Oral administration of the melon pulp extract at doses of  200 and 600 mg/kg to rats  reduced gastric mucosal lesions  dose-dependently  with percentage protection of 56.56 and 93.79% compared to omeprazole (95.92 %) as reference drug. These results showed that the melon pulp extract had a good antioxidant activity and gastroprotective potential suggesting it use as an adjuvant in the treatment of gastric ulcer. Keywords: Cucumis melo var. inodorus, Polyphenols, Flavonoids, Tannins, Ulcer, Rat

Protective effects of Trigonella foenum-graecum crude extract over damage induced by Sreptozotocin diabetes rats

The seeds of Trigonella foenum-graecum (fenugreek) are used for treatment of diabetes mellitus in traditional medicine. This paper examines the protection effects of fenugreek from the damage induced by streptozotocin diabetes rats. Tannins content of T. foenum-graecum was also estimated in vitro. Normoglycemic male Wistar rats, weighing 170-250 g, were selected and randomly divided into five groups (n= 6): normal control, diabetic + TFGE (200mg/kg), diabetic+ TFGE (600mg/kg), diabetic + Glibil (3mg/kg), untreated group. Diabetes was induced after a single intraperitoneal injection of streptozotocin (50 mg/kg body weight) and Fenugreek was given every day via orogastric tube for 18 days. At the end of experiment, rats were sacarificed. Organ weight was estimated of all groups. Trigonella foenum-graecum administration significantly improved the polydipsia, polyphagia, and it also compensated weight loss of diabetic rats (P<0.05, P < 0.01). Moreover, fenugreek had a significant concentration of tannins (806.22 ±0.036 µg TAE/gE). The results revealed that fenugreek improves the damage in diabetic rats that in some ways validates the traditional use of this plant in treatment of diabetes. Keywords: Antidiabetic activity, Protective effect, Streptozotocin, Tannins, Trigonella foenum-graecu

Antioxidant Evaluation and Polyphenol Contents of Hydro Ethanolic Extract’s Fractions from Ephedra nebrodensis

Ephedra nebrodensis, is a medicinal plant, traditionally in Algeria used for the cure of various ailments such as hepatic disorders. On this basis in present study the phytochemical screening and in vitro antioxidant activity of various fractions (n-hexane, chloroform, ethyl acetate, n-butanol and water) of ethanol extract obtained by maceration from aerial parts of E. nebrodensis were investigated. Different fractions were accessed for their yield percentage, total polyphenol content (TPC), total flavonoid content (TFC), total tannins content (TTC) and antioxidant potential (DPPH - 2,2-diphenyl-1-picrylhydrazyl; ABTS - 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid), reducing power assay (FRAP - ferric reducing antioxidant power activity),and bleaching of β-carotene test . Results showed that ethyl acetate fraction (EF) represents the highest amount of total polyphenols, flavonoids and tannins with 269.669 ± 0.031 µg gallic acid equivalent/mg of DE, 44.507 ± 0.003 µg quercetin equivalents/mg of DE and 228.487 ± 1.362 µg tannic acid equivalents/mg of DE, respectively. In antioxidant assays, ethyl acetate fractions (EF) showed the strongest DPPH and ABTS antioxidant (IC50: 0.009 and 0.004 µg/mL) and FRAP potential (EC50: 0.005 ± 0.000 µg/mL), which significantly correlate to its high content of polyphenolics, flavonoids and tannins. Further, fractions were rich in phenolic compounds. The present results support the possible use of the ethyl acetate fraction from E. nebrodensis in pharmaceutical industries as a natural antioxidant. Keywords: Ephedra nebrodensis, polyphenols, flavonoids, tannins, antioxidant capacity

Screening of Antimicrobial and Antioxidant Secondary Metabolites from Endophytic Fungi Isolated from Wheat (Triticum Durum)

Abstract: The emergence of antibiotic-resistant micro-organisms calls for inventive research and development strategies. Inhibition of these pathogenic micro-organisms may be a promising therapeutic approach. The screening of antimicrobial compounds from endophytes is a promising way to meet the increasing threat of drug-resistant strains of human and plant pathogens. In the present study, a total of 20 endophytic fungi and 23 endophytic actinomycetes have been isolated from wheat (Triticum durum). Mohamed Ben Bachir variety collected from Bordj Bou Arreridj region (Algeria) during winter 2010. The isolates were screened and evaluated for their antimicrobial and antioxidant activities. Antimicrobial activity was evaluated for crude ethyl acetate extracts using an agar dif-fusion assay against twelve pathogenic bacteria, yeast, and two phytopathogenic fungi. All extracts showed inhibitory activity on at least one or more pathogenic microorganisms, with an average zone of inhibition varied between 7 mm to 25 mm, and the largest zone was of 25 and 25.3 mm against candida albicans and Escherichia coli respectively. The antioxidant capacity of the extracts was evalu-ated by β-carotene/linoleic acid assay. Results showed that 60 % of these extracts have antioxidant activity, exhibiting 50, 57 % to 78, 96 % inhibitions. While the inhibitory activity for oxidation of linoleic acid of 40 % of them was less than 50%. From the present work it is possible to conclude that these microorganisms could be promising source of bioactive compounds, and warrant further study. Key words: endophytic microorganisms, antimicrobial activity, antioxidant activity, Triticum duru