Search

In this study, we examined the combined effect of moderate salinity (100 mM NaCl) and three phosphorus (P) levels: low, moderate and high (5 µM, 60 µM and 180 µM KH2PO4, respectively) on several physiological parameters in the facultative halophyte Aeluropus littoralis. Our results showed that plants cultivated under low P availability exhibited higher leaf hair and trichome densities, root length, and shoot soluble sugars concentrations. The response of plants to combined salinity and P deficiency was similar to that of plants cultivated under P deficiency only. Furthermore, in the absence of salt, A. littoralis plants reached maximum biomass at 180 µMP. However, in the presence of 100 mM NaCl, plants exhibited maximum growth from 60 µMP which suggests that salt supply decreased P requirements of A. littoralis plants. Moreover, salinity has no significant effect on biomass production, shoot water content and shoot potassium (K+) content when combined with 5 µMP and it significantly decreased gradually these parameters when combined with 60 µMP and 180 µMP. This was associated with higher values of P and K use efficiencies, leaf hair and trichome densities, total polyphenol content, and total antioxidant capacity in plants cultivated under combined effects of salinity and P deficiency. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterise phenolic compounds of olive flower obtained from Olive tree cultivar Chemlali and to investigate their anticancer effect on MCF-7 cells. Phenolic characterisation was determined using LC/MS-MS. Cytotoxicity of the extract was determined using MTT. Biochemical markers of apoptosis were evaluated by immunoblotting. Our results showed that olive flower contained significant amounts of phenolic compounds mainly flavonoids, secoiridoids and simple phenols. Furthermore, the phenolic extract exerted a significant reduction in MCF-7 cell viability (EC50 values equal to 220.8 μg/ml). Western blot analysis revealed the presence of the cleaved forms of Parp-1. The DAPI staining analysis demonstrated a significant reduction in the number of cells and a considerable change in the morphology of the treated cells. In conclusion, Olea europaea. L flower contained great amounts of different bio-phenols able to reduce the proliferative activity of breast cancer MCF-7 cells by the induction of apoptosis. [ABSTRACT FROM AUTHOR]

Artemisia herba-alba (Aha) is an aromatic and medicinal plant rich in health-promoting flavonoids compounds that play an important role as antioxidant. For better utilization of this resource, the ultrasound-assisted extraction (UAE) of flavonoids and antiradical activities of obtained extracts from Aha using response surface methodology was assessed. A four-factor five-level central composite rotatable design was employed to discuss these extracting parameters: ethanol concentration (X1), temperature (X2), extraction time (X3) and solvent to sample ratio (X4). The optimum extraction conditions for simultaneous maximization of total flavonoids (TF) and scavenging activity were solvent concentration of 50%, temperature of 55 °C, extraction time of 50 min and solvent to sample ratio of 90 mL/g. Under these conditions, the experimental yield of TF and DPPH-radical scavenging activity IC50% were respectively 102.49 mg CE/g DM and 7 µg/mL. Additionally, good and moderate linear correlation was observed between antiradical activity and TF content (R2 = 0.709) which indicated that these compounds are responsible for antioxidant activity of Aha. When compared to the most conventional extraction, antioxidant activity and amounts of major flavonoids are enhanced when using UAE with reduced extraction time. [ABSTRACT FROM AUTHOR]

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]