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Tamarix gallica L. is a halophytic medicinal shrub traditionally used in the treatment of liver disorders. Leaf and flower infusions are widely used for anti-diarrheic and anti-inflammatory preparations. In this work, we have explored the combined effect of method (Maceration and Decoction) and solvent extraction (70% Methanol, 70% Ethanol, 70% Acetone, and Water) on phenolic composition and biological activities (antioxidant and anti-inflammatory) of different T. gallica organ extracts (Leaves, Flowers, Stems, and Fruits). Obtained results showed that Tamarix leaves reveal more potent antioxidant activity. Methanol (70%) was the best maceration solvent for the extraction of leaves and flowers with high total antioxidant and anti-radical capacities. HPLC analysis showed that catechin, isorhamnetin-3- O -glucoside, isoquercetin were the major phenolics in 70% methanolic extract. Furthermore, this extract showed considerable anti-inflammatory activity. This prospect could be of great importance in the valuation of this halophyte as a source of natural antioxidants and anti-inflammatory drugs.

This study investigates the polyphenol content of Diplotaxis simplex extract and the biological activities of the main organ. The analysed extracts showed that polyphenol contents varied considerably as a function of organs. Furthermore, novel biological activities of this species were assessed. Flower extracts exhibit a potent in vitro antioxidant capacity using oxygen radical absorbance capacity and displayed a strong anti-inflammatory activity, inhibiting nitric oxide release, by 79.3% at 160 μg/mL. Our findings suggested that the Diplotaxis flower is a valuable source of antioxidants and anti-inflammatory agents.

Background: Fe deficiency affects food growth and quality in calcareous soils. In this study, the effect of Fe deficiency on growth parameters, phenolic content and antioxidant capacities of two lettuce shoots varieties (Romaine and Vista) were investigated., Results: Fresh matter production, pigment (chlorophyll and carotenoid) and Fe2+ content were significantly reduced by Fe deficiency in both varieties. However, restriction of these parameters was particularly pronounced in Romaine variety as compared to Vista. Moreover, Fe deficiency caused decreases in the activity of antioxidant enzymes such as catalase and guaiacol peroxidase, whereas ascorbate peroxidase and malondialdehyde concentrations were not significantly affected. On the other hand, Fe deficiency in Vista variety induced an increase in polyphenol and flavonoid content as compared to Romaine variety. In addition, total antioxidant capacity and antiradical test against DPPH radical decreased in leaves of Romaine variety after 15 days of treatment., Conclusion: These results suggest that the higher polyphenol content in Vista variety supports the involvement of these components in the stability of antioxidant capacities and then in its protection against oxidative damage generated by Fe deficiency in lettuce plants., (© 2012 Society of Chemical Industry.)

The antioxidant capacities of the crude extract, aqueous and ethyl acetate partitions of Limoniastrum guyonianum Boiss. (Zita) were investigated in this study. The ethyl acetate phase exhibited a significant antioxidant activity as judged by total antioxidant activity, DPPH test and reducing power. Fractionation of this extract by centrifugal partition chromatography (CPC) using quaternary Arizona solvent systems composed of n-heptane/ethyl acetate/methanol/water led to ten fractions. The antioxidant capacities of these fractions were assessed using the same previous tests. Fraction 8 showed the highest antioxidant capacity (1291.1mg GAE/g DR), the power ability to quench DPPH radical (IC(50)=2μg/ml) and to reduce Fe(3+) (EC(50)=65μg/ml). From this fraction, three powerful flavonoids were isolated (1-3): gallocatechin (1), epigallocatechin (2) and epigallocatechin-3-O-gallate (3). These findings suggest that the antioxidative property of L. guynianum is may be related to the presence of these flavonoids, which can be used in various industrial fields., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Organic wastes were successfully used as soil amendment to improve agrosystems productivity. Yet, the effectiveness of this practice to enhance plant antioxidant capacities has received little attention. Here, we assess the effect of municipal solid waste (MSW) compost (at 40 t ha(-1)) on growth, polyphenol contents and antioxidant activities of Mesembryanthemum edule. MSW compost application significantly increased the soil contents of carbon, nitrogen, calcium, phosphorus and potassium. This was associated with higher nutrient (N, P, and K) uptake, which likely led to the significant improvement of the plant biomass and relative growth rate (RGR) (+93% on average) as compared to the control. In the same way, the fertilizing effect of the added organic matter significantly enhanced the antioxidant potential M. edule, assessed by radical scavenging activity, iron reducing power and β-carotene bleaching capacity. This was associated with significantly higher antioxidant contents, mainly total phenols and flavonoids. Heavy metal (Pb, Cd, Cu, and Zn) concentrations were slightly increased upon compost application, but remained lower than phytotoxic values. Overall, our results point out that short-term MSW compost application at 40 t ha(-1) is efficient in enhancing the productivity together with the antioxidant potentiality of M. edule without any adverse environmental impact., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The current study aimed to evaluate Tunisian Tamarix africana Poir biological activities. In this study, novel biological activities of the shoot extracts related to their phenolics investigated. Secondary metabolite contents, antioxidant, anti-inflammatory and cytotoxic activities of four extracts (hexane, dichloromethane, methanol and water) were investigated. Antioxidant activities were assessed via in vitro and ex vivo assays. Besides, anticancer activity was investigated against human lung carcinoma (A-549) and colon adenocarcinoma (DLD-1) cells. The anti-inflammatory ability was evaluated via inhibition of LPS-induced NO production in RAW 264.7 macrophage cell lines. Methanol and water extracts displayed the highest antioxidant (IC50 = 3.3 and 4.3 µg/mL respectively), which are correlated activities correlated with phenolic contents. Hexane extract exhibited an important anti-inflammatory effect inhibiting NO ability by 100% at 80 µg/mL. Besides, T. africana extracts were found to be active against A-549 lung carcinoma cells with IC50 values ranging from 20 to 34 µg/mL. These results suggested that T. africana is considered as a potential source of readily accessible natural molecules with a promising effect on human health and diseases. [ABSTRACT FROM AUTHOR]

Highlights: [•] Isolation of new dimer and two natural monomers of phenolic acid amides from Limoniastrum guyonianum. [•] Determination of their structures structure and stereochemistry were determined by NMR. [•] Estimation of the antioxidant activities of these molecules. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fractionation of the ethyl acetate partition of Limoniastrum guyonianum by CPC. [•] Assessment of phenolic contents of the 10 fractions. [•] Investigation of the antioxidant activities of Limoniastrum fractions. [•] Exploration of the anti-amyloidogenic and the antibacterial capacities of fractions. [•] Determination of phenolic composition by HPLC of the most active fractions. [ABSTRACT FROM AUTHOR]

Abstract: Suaeda fruticosa is an edible and medicinal halophyte known for its hypoglycaemic and hypolipidaemic activities. In this study, novel biological activities of the shoot extracts related to their phenolics were investigated. Results showed an appreciable total phenolic (31.8mgGAE/gDW) in shoot extracts. The estimation of antioxidant capacities using oxygen radical absorbance capacity (ORAC method) and a cell based-assay (WS1) of four extracts (hexane, dichloromethane, methanol and water) showed that shoot methanol extract exhibit the highest antioxidant activities. The same extract displayed the utmost anti-inflammatory activity, inhibiting nitric oxide (NO) release, by 66.4% at 160μg/ml in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Besides, the dichloromethane extract showed the highest anticancer activity against human lung carcinoma (A-549) and colon adenocarcinoma cell lines (DLD-1, Caco-2 and HT-29) with specificity against DLD-1 (IC50 =10±1μg/ml). These findings demonstrate the remarkable potentiality of this edible halophyte as valuable source of antioxidants which exhibit original and interesting anti-inflammatory and anticancer capacities. [Copyright &y& Elsevier]

Abstract: Antioxidants are the chemical substances that reduce or prevent oxidation. The present study aimed to assess in vitro and ex vivo antioxidant activities of four acetonic extracts Tunisian halophytes (Suaeda fruticosa, Suaeda pruinosa, Suaeda mollis and Suaeda maritima). Various experimental models were used for characterization of antioxidant activities of shoot extracts. Eventually, the promising specie was subjected to phenolic identification using RP-HPLC. The analyzed shoot extracts exhibited that antioxidant activities varied considerably as function of species. The highest DPPHng ability was found in S. mollis with the lowest IC50 value (2.5μg/ml), followed by S. pruinosa, S. fruticosa and S. maritima. The same tendency was observed with ferric reducing power. Concerning β-carotene bleaching assays and total antioxidant activity, results showed that S. fruticosa exhibited the highest antioxidant ability against the inhibition of β-carotene bleaching, and a better total antioxidant capacity. Moreover antioxidant capacities using ORAC method and a cell based-assay showed that S. mollis, S. fruticosa, and S. pruinosa exhibit statistically similar antioxidant activity. The identification of phenolic compounds in S. mollis extract using RP-HPLC revealed that 2,5-dihydroxybenzoic acid and rutin hydrate were the major molecules. These results suggested that Suaeda species showed a variability of their antioxidant activities. [Copyright &y& Elsevier]

Abstract: Mesembryanthemum edule is used as a food ingredient and in traditional medicine. In this study, we investigated antioxidant activities of several extracts (methanol/acidified water, v/v: 20/80; 40/60 and 60/40) obtained from M. edule leaf, stem and root. Then, individual phenolics were characterised by reverse-phase HPLC coupled to electrospray ionisation mass spectrometry and multi-stage MS fragment analysis. Results showed that 40% methanol leaf extract, 40% methanol root extract and 20% methanol stem extract displayed the highest scavenging activity against DPPH and ABTS radicals. Regarding LC/ESI-MS/MS identification of active phenols, there were significant differences among the fractions of interest. In fact, 40% leaf extract mainly contained procyanidins, whereas propelargonidins were the major phenolics in 20% methanol stem extract, while, in 40% root extract, the active compounds remained unidentified. These results indicate that edible M. edule can be used as a nutraceutical in the pharmaceutical industry. [Copyright &y& Elsevier]

Abstract: Diplotaxis species are edible and medicinal plants. This study investigates phenolic contents and biological activities in stems, leaves, and flowers of Diplotaxis harra and Diplotaxis simplex. Flowers exhibited the highest polyphenol content and D. harra was significantly more phenol-rich than D. simplex. Similarly, the highest antioxidant activities were found in D. harra flowers. Fractionation of D. harra extract revealed that 60% MeOH fraction showed the best antioxidant activities. Indeed, flower fractions were assayed for their activity against human pathogenic bacteria and the inhibitory percentages reached 100%. As regards fraction polarity, 60% and 80% MeOH fractions were the most active ones. Moreover, HPLC analysis showed that the main phenolic compound was cafeic acid for the two species, whereas p-Coumaric and 3,4-dimethoxybenzoic acids were identified only in D. simplex and sinapic acid was exclusive to D. harra. Overall, our findings indicate that Diplotaxis flowers could be used as a potent source of natural antioxidants and antibiotics. [Copyright &y& Elsevier]