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This research can be considered as the first complete survey for the valorization of new olive genotypes cultivated in the South-East of Tunisia as well as their oils. The study aimed to characterize the phytochemical composition of virgin olive oil produced from two olive cultivars, namely Nourgou and Gousalani. The pomological characterization of fruits, the quality criteria and the phytochemical profile were quantified. Additionally, antioxidant activity was evaluated using Ferric reducing antioxidant power (FRAP) and Oxygen radical absorbance capacity (ORAC) tests to also obtain a bioactive characterization of these monovarietal olive oils. The obtained results revealed that the analyzed olive oils samples can be classified into Extra Virgin category (EVOO) according to the regulated physicochemical characteristics. Our findings showed a significant variability in the chemical parameters of the analyzed EVOO likely associated with the genetic potential, mainly for chlorophylls contents (1.37–1.64 mg/kg), in carotenoids pigments (3.97–10.86 mg/kg), in α-tocopherol (175.59–186.87 mg/kg), in sterols (1036.4–1931.4 mg/kg) in oleic acid (65.33–68.73%), in palmitic acid (C16:0) (13.32–17.48%), in linoleic acid (C18:2) (11.06–13.47%). Additionally, the HPLC-MS/MS analysis showed that the two EVOOs analyzed contained appreciable amounts of total polyphenols, ranging from 348.03 up to 516.16 mg/kg, in Nourgou and Gousalani oils, respectively. Regarding the individual phenolic compounds, the EVOO samples were mainly characterized by phenolic alcohols, phenolic acids, secoiridoids, verbascoside, flavonoids and phenolic aldehydes. The prevalent simple phenolics detected were secoiridoids with the dominance of the oleuropein aglycone in Gousalani oil. In addition, findings from in vitro antioxidant assays (FRAP and ORAC) revealed that the two studied oils possessed a powerful antiradical activity and a good reducing power capacity. In conclusion, these new EVOOs exhibited a superior quality compared to other Tunisian varieties, considering their antiradical activity and reducing power capacity. [ABSTRACT FROM AUTHOR]

In arid and semiarid regions, salinity may affect alfalfa (Medicago sativa) productivity and survival due to either cultivation on salt‐affected soils or the use of salinized irrigation water. Exploiting germplasm evolved under salt‐stress conditions offers opportunities for crop tolerance improvement. In the first phase of the current study, four reportedly salt‐tolerant landraces originated from stress‐prone areas of West Asia or North Africa and two reference commercial cultivars underwent three evaluation trials according to different methods, namely, seed germination in saline water, in vitro testing of young plants, and greenhouse evaluation of adult plants in Cone‐tainers. Experimental populations obtained by intercrossing landrace genotypes selected according to each evaluation method were subsequently evaluated under stressful field conditions in two regions featuring different salt stress type, namely, southern Tunisia (irrigation with saline water) and northwestern Argentina (rainfed cropping in saline soil). Landrace ranking for salt tolerance differed somewhat depending on the evaluation method, and the proportion of selected plants per landrace depended accordingly on the method. In each field experiment, there were two evaluation phases, and the second phase corresponded in both cases to harsher conditions. The in vitro evaluation and selection resulted in potentially more useful selected germplasm than the other evaluation methods. The field experiments highlighted the large specific adaptation effects that affected the response of salt‐tolerant germplasm across the two regions. Core Ideas: Cultivation on salt‐affected soils or the use of salinized irrigation water affects alfalfa productivity and survival.Landraces evolved in stress‐affected areas are valuable genetic resources for salt tolerance improvement.Selections for salt tolerance from different methods in controlled conditions differ for field‐based tolerance.In vitro evaluation and selection provided potentially more useful selected germplasm than other methods.Specific adaptation affected the field response of salt‐tolerant germplasm across different regions. [ABSTRACT FROM AUTHOR]

A field experiment focusing on the response of Tossa jute (Corchorus olitorius L.) to salt stress at germination and vegetative growth stages was held in the Institute of Arid Lands of Medenine, Tunisia. Results showed that germinating rate after 24 hrs exceeded 50% under salt levels between 0 and 5 g.l-1. Indeed, salt stress levels delayed the initiation process and decreased significantly kinetics and rate of germination, which were severely limited at 9 and 10 g.l-1 NaCl. After one month of growth, Tossa jute seedlings were subjected to salt treatments of 2, 4, 6, and 8 g.l-1 NaCl. After four weeks of stress in pots, morphological responses were reflected by a significant decrease in parameters of growth and yield when salinity reached 8 g.l-1. Indeed, a reduction in the photosynthetic gaseous exchange and a stomata resistance were notified for seedlings subjected to 6 and 8 g.l-1 NaCl treatments. However, in order to tolerate the highest levels of salt, Tossa jute seedlings make different strategies by reducing the size of leaves, which increases their accumulation of osmolytes such as proline (3.1 mg.g-1 DM) and soluble sugars (13.22 μg.g-1 FM) to permitting the osmotic adjustment. [ABSTRACT FROM AUTHOR]

In the present study, the phenolic compounds, mineral composition, of ethanol and water extracts from different Reamuria vermiculata parts (leaves, stems and roots) was investigated. The antioxidant and antimicrobial proprieties were screened using experimental and computational approaches. Results have reported that the fraction aqueous of roots had a higher amount of polyphenol, flavonoid and tanins than stems and leaves (1153.29 mg GAE/g, 308.16 mg CE/g, 31.84 mg CE/g DW) respectively. Also, the same extract has significant scavenging activity to decrease free radicals especially for DPPH (IC50 = 0.04 mg/mL), ABTS radicals (IC50 = 0.002 mg/mL) and ß-carotene (IC50 = 0.06 mg/mL). In addition, the minerals K, Mg, Na, and Ca were detected as considerably high quantities in leaves. Moreover, the ethanol extract of roots exhibited an antimicrobial property against bacterial strains Listeria monocytogenes with MIC =0.0781 mg/ml, staphylococcus aureus and Bacillus subtilis with MIC = 0.3125 mg/ml. The overall results provided some valuable information that spices have powerful antioxidant and antimicrobial potentials, which could be an interesting material for industrial purposes. [ABSTRACT FROM AUTHOR]