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The combined effects of NaCl-salinity and phosphorus deficiency on biomass production, nutritional status, and photosynthetic activity were studied in Catapodium rigidum: an annual Poacea with fodder potential. Plants were grown in hydroponic conditions for 55 days under two phosphorus (P) supply: 5 (low) or 180 µmol KH2PO4 (sufficient), in the absence or presence of 100 mM NaCl. Obtained results demonstrated that both salinity and P deficiency treatments applied separately reduced substantially plant growth and CO2 assimilation rate with a more marked impact of salt stress. Salinity has no substantial effect on both shoot P concentrations and phosphorus acquisition efficiency independently of P availability. The highest decrease in plant growth (−91%) was observed in plants simultaneously submitted to both stresses suggesting an additive effect of the two stresses and that P deficiency increased the susceptibility of C. rigidum to salinity. This may be linked to a significant decrease in potassium acquisition (−95%), K/Na selectivity ratio (−73%), stomatal conductance (−66%), CO2 assimilation rate (−64%), and shoot water content (66%). Furthermore, plants cultivated under combined salinity and sufficient P supply displayed higher stomatal conductance, CO2 assimilation rate, K/Na selectivity ratio, and plant growth than plants cultivated under combined effects of salinity and P deficiency. These results suggest that adding P to saline soils could be an alternative for alleviating the negative effects of salinity and may ameliorate salinity tolerance. [ABSTRACT FROM AUTHOR]

O-Methylated and glucuronosylated flavonoids were isolated fromTamarix gallicaas α-glucosidase inhibitors. Structure–activity relationship of these flavonoids suggests that catechol moiety and glucuronic acid at C-3 are factors in the increase in α-glucosidase inhibitory activity. Furthermore, rhamnetin, tamarixetin, rhamnazin, KGlcA, KGlcA-Me, QGlcA, and QGlcA-Me exhibit synergistic potential when applied with a very low concentration of acarbose to α-glucosidase from rat intestine. [ABSTRACT FROM PUBLISHER]

Sea barely (Hordeum marinum Huds.) is known as a salinity-tolerant annual grass species. Its use in the rehabilitation of degraded arid and semiarid rangelands or in crop plant improvement programs is of great interest. In this study, we investigated the phenotypic variation within and among 150 single-seed descent families representing 10 Tunisian populations of H. marinum using eight quantitative traits. The experiment was conducted under greenhouse conditions. For each population, seeds from 15 mother plants were evaluated with five replicates per mother plant. Our results showed significant variation within and between populations for most measured traits. Most phenotypic variation was found to occur within populations. The QST measurement of differentiation between populations varied according to traits from 0.03 for number of tillers to 0.309 for the weight of aerial part, with an average of 0.149. Pairwise QST grouped studied populations into three major clusters; the first group included Tabarka and Sidi Othman populations showing the lowest values for spike number and weight. The second group included Lessouda, Bouficha, and Mouthul having the highest values for the number and weight of spikes, while the third group included populations Lac de Bizerte, Sebkhet Ferjouna, Bkalta, Medjez El Bab, and Soliman and had moderate spike number and weight. Furthermore, there was no significant association between population differentiation and ecogeographical parameters. [ABSTRACT FROM AUTHOR]

In this work we studied the effect of salinity (ranging from 50 to 500mM NaCl) on the physiological and the antioxidant responses of the local halophyte Limonium delicatulum Kuntze. We based our analysis on 12 biochemical assays that are commonly used to measure the antioxidant responses under stress such as oxidative stress markers, enzymes activities and polyphenolic compounds. Our aim was to study parameters that are strongly correlated with the growth response to salinity. Results showed two different growth responses depending on the concentration of NaCl in the medium. Under 50 to 200 mM, the growth was stimulated before it decreased significantly at 300-500 mM. L. delicatulum revealed a good aptitude to maintain photosynthetic machinery by increasing the concentrations of photosynthetic pigments, which is essential for the stabilisation of photosystems and the photosynthesis process under optimal NaCl concentration. Their breakdown at higher salinity decreased the photosynthetic performance of plants resulting in growth inhibition. Moreover, to reduce the damaging effect of oxidative stress and to tolerate the accumulation of salt ions, L. delicatulum induced the activities of their antioxidant enzymes more than their contents in polyphenolic compounds. [ABSTRACT FROM AUTHOR]

The presentstudydescribes the biochemical evaluation of Silybum marianum seed. The analysis of essential oil composition of Silybum marianum seed by Gas Chromatography-Mass Spectrometry GC-MS showed the presence of14 volatile components with the predominance of γ-cadinene (49.8%) and α-pinene (24.5%). Whereas, the analysis of fatty acids composition, showed the predominance of linoleic (50.5%) and oleic (30.2%) acids. Silybum marainum presented also an important polyphenol contents with 29mgGAE/g DW, a good antiradical activity (CI50=39μg/ml) but a lower reducing power ability. Flavonoid and condensed tannin contents were about 3.39mg EC/g DW and 1.8mg EC/gDW, respectively. The main phenolic compounds identified by RP-HPLC, were silybin A (12.2%), silybin B (17.67%), isosilybin A (21.9%), isosilybin B (12.8%), silychristin (7.9%) andsilydianin (7.5%). [ABSTRACT FROM AUTHOR]

Taking into account that oxidative stress is among the factors causing cancer-related death; chemoprevention which consists in using antioxidant substances such as phenolics could prevent cancer formation and progression. In the present study, phenolic contents and antioxidant activities of methanolic extracts from the halophyte Tamarix gallica shoots were determined. Moreover, the anticancer effect of this species on human colon cancer cells and the likely underlying mechanisms were also investigated. Shoot extracts showed an appreciable total phenolic content (85 mg GAE/g DW) and a high antioxidant activity (IC 50 = 3.3 μg/ml for DPPH test). At 50 and 100 μg/ml, shoot, leaf, and flower extracts significantly inhibited Caco-2 cell growth. For instance, almost all plant part extracts inhibited cell growth by 62 % at the concentration 100 μg/ml. DAPI staining results revealed that these extracts decrease DNA synthesis and confirm their effect on Caco-2 cells proliferation, principally at 100 μg/ml. More importantly, cell mitosis was arrested at G 2/M phase. The changes in the cell-cycle-associated proteins (cyclin B1, p38, Erk1/2, Chk1, and Chk2) are correlated with the changes in cell cycle distribution. Taken together, our data suggest that T. gallica is a promising candidate species to be used as a source of anticancer biomolecules. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to evaluate the ability of the indifferent halophyte Sulla carnosa Desf. to desalinize a moderately-salt-affected soil. Seeds were sown on a fertile soil added or not with 1.5 g NaCl. kg−1. Analogous treatments without plantation (control and salinized) were also used. Plant culture was performed under greenhouse conditions in non-perforated pots containing 10 kg soil each and irrigated with non-saline tap water. After 80 days of treatment, shoots were harvested. Soil samples were also collected after division of soil column in each pot into two horizons. Our results showed that salt addition increased electrical conductivity of saturation paste extract (ECe) from 3.3 to 8.4 dS. m−1 and soluble sodium concentration from 0.32 to 1.15 g. kg−1 soil in the upper horizon. In the lower horizon however, Na+ concentration was quasi-constant and then ECe was less increased. Plant culture inversed this pattern of sodium accumulation and salinity. Its productivity and phytodesalination capacity in 80 days were 5.0 t DW. ha−1 and 0.3 t Na+. ha−1 (24% of the added quantity), respectively. Interestingly, sodium dilution within biomass (41.5–45.6 mg. g−1 DW) and the non-altered nutrition make this plant suitable for forage as second use after phytodesalination. [ABSTRACT FROM AUTHOR]

In the present work, we studied the effectiveness of the predominant halophytes of Soliman sabkha (Tecticornia indica and Suaeda fruticosa) to promote soil biological activities and ecosystem productivity. Soil Arylsulphatese ARY, β-glucosidase β-GLU, phosphatase PHO, invertase INV, urease URE, and dehydogenase DES activities in Extra- and Intra-tuft halophytes and plant productivity were assessed. Results revealed a high increase of microbial community and ARY, β-GLU, PHO, INV, URE and DES activities (+298%, +400%, +800%, +350%, +320%, +25% and +759%, respectively) in Intra-tuft rhizosphere as compared to Extra-tuft one, which is likely due to the significant decrease of salinity in the rhizosphere of Tecticornia indica and Suaeda fruticosa. Both perennial plants exhibited high productivities (7.4 t dry weight ha−1 and 2.2 t dry weight ha−1, respectively) and Na+-hyperaccumulating capacities (0.75 t Na+ ha−1 and 0.22 t Na+ ha−1, respectively), reducing salt constraint and favouring soil fertility. This constitutes a promising alternative to enhance productivity in such a salt-affected biotope by offering suitable microhabitat for annual glycophytes. [ABSTRACT FROM PUBLISHER]

Energy metabolism is a very important process to improve and maintain health from the point of view of physiology. It is well known that the intracellular ATP production is contributed to energy metabolism in cells. Cistus monspeliensis is widely used as tea, spices, and medical herb; however, it has not been focusing on the activation of energy metabolism. In this study, C. monspeliensis was investigated as the food resources by activation of energy metabolism in human intestinal epithelial cells. C. monspeliensis extract showed high antioxidant ability. In addition, the promotion of metabolites of glycolysis and TCA cycle was induced by C. monspeliensis treatment. [ABSTRACT FROM AUTHOR]

Saline habitats contain various salt types that differently affect seed germination and subsequent seedling establishment. Most studies on the germination process have been carried out using NaCl, which may limit the accuracy of the conclusions drawn, especially regarding the plant behaviour under field conditions. We compare here the impact of iso-osmotic solutions of four salts (NaCl, Na2SO4, MgCl2 and MgSO4 ) and mannitol on seed imbibition, germination, germination recovery, viability and seedling ion relations of the halophyte Crithmum maritimum L. Seed imbibition percentage declined as osmotic potentials decreased. MgCl2 and NaCl were the most and less adverse salt on the germination, respectively. As for seed germination and viability, K+, Ca2+, NO3- and PO43- contents within seedlings appeared to be salt-diminished. This was associated with higher ion (K+ and Ca2+ ) leakage. In conclusion, both osmotic and toxic salt components impaired seed germination. This may be related to the effects of different salts on ion content, seed imbibition, and nutrient leakage through membranes. [ABSTRACT FROM AUTHOR]

Reaumuria vermiculata is a xero-halophytic specie widely distributed in the south of Tunisia. In the current study, antioxidant, anti-inflammatory and anticancer activities of Reaumuria vermiculata shoot extracts as well as its phenolic compounds were investigated in different solvent extracts (hexane, dichloromethane, methanol and water). Results showed a strong antioxidant activity, using the ORAC method and a cell based-assay, in methanol extract as well as an important phenolic composition (117.12 mg GAE/g). Hexane and dichloromethane proved an interesting anticancer activity against A-549 lung carcinoma cells, with IC50 values of 17 and 23 µg/ml, respectively. Besides, dichloromethane extract displayed the utmost anti-inflammatory activity, inhibiting NO release over 100 % at 80 µg/ml in LPS-stimulated RAW 264.7. Taken together, these finding suggest that R. vermiculata exhibited an interesting biological activities which may be related to the phenolic composition of this plant. Moreover, the identification of phenolic compounds in R. vermiculata dichloromethane extract using RP-HPLC revealed that myricetin was the major molecule. These results allow us to propose R. vermiculata as a valuable source for bioactive and natural compounds exhibiting interesting biological capacities.