Peels and fresh pomegranate extracts were used in the present study for the determination of the physic-chemical properties and DPPH-ABTS scavenging activities. Total sugars of juice are fructose (ca. 7 g/100 ml) and glucose (ca. 8 g/100 ml). Contents of soluble proteins in juice extracts are about 7 g/l (Bradford assays) and 22% (Kjeldhal assays) from dry pulp. Minerals in peel and juice are respectively 9.43+/-0.93 and 9.46+/-1.05 mg/100 ml for posphorus and 210.86+/-10.70 and 271.94+/-60.59 mg/100 g for potassium. The sodium contents are nearly 7 mg/100 ml in both peel and juice. Highly antioxidant contents in peels were confirmed. Free radical scavenging is about 3.58+/-0.38 microg/ml in peel. The antioxidant capacity value determined by ABTS was 7.364+/-0.403 mM Trolox equivalent antioxidant capacity/100 g dry weight. These findings implied that bio-active compounds from the peel might be potential resources for the development of antioxidant function dietary food.

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The Ceratonia siliqua fruits contain several substances known to have high adaptability to environmental conditions. The aim of this paper is to evaluate the changes in physicochemical properties of different Tunisian provenances of carob pulps harvested at three ripening stages. Furthermore, six provenances were investigated during the ripening process in terms of their moisture, ash, minerals, bioactive compounds, antiradical activity and sugar profile. The results demonstrated that all examined parameters are highly influenced by geographic origin. Concerning ripening impact, our data showed that water and ash content significantly decreased during the development of six provenances, as well as the bioactive and mineral contents. Thus, the total polyphenols (TP), total flavonoids (TF) and condensed tannins (CT) contents exhibited the highest levels in the unripe fruits. The antiradical activity trend was positively correlated to the behavior of the bioactive compounds content. Moreover, the sucrose, glucose and fructose were the main sugar qualified and quantified in carob pods at different ripening stages. At the maturity stage, the monosaccharide contents (glucose and fructose) were slightly reduced, while, the sucrose was rapidly accumulated. In conclusion, the ripening process diversely affected the nutritional composition and generally extended the exploitation of carob fruits. The study could provide valuable information about the suitability of carob pods at different maturity stages as potential biomaterials for nutraceutical applications.

Barley "Ardhaoui" (Hordeum vulgare L.) is a local landraces cropped in southern Tunisia characterized by its resistance to drought and salinity. Salt tolerance of barley changes according to the growth stages. In order to study the salinity tolerance of (Hordeum vulgare L.), fourteen barely accessions, were grown in soil and exposed to four salinity levels (5, 7, 13 and 20 dS/m).To evaluate its salt tolerance using multiple parameters, fourteen barley accessions from two regions in the southern Tunisia (costal and mountainous regions) were grown in soil and exposed to four salinity levels (5, 7, 13 and 20 dS/m). Plant growth parameter, total biomass at final harvest, straw yield and yield compound associated with salt tolerance during the different growth stages were determined. The results showed negative effects of salinity on the growth and the development of the barley. However, the salt sensitive accessions showed a greater reduction in tiller number (e.g. by about 80 %) than tolerant ones (e.g. by about 57 %) at 20 dS/m. These decrease on the growth of leaves, tillers and the aerial part constitute a strategy developed by the barely in vegetative phase to reduce the salt stress. Tiller and spikelet numbers were more affected by the salinity at 13 and 20 dS/m the different results showed significant correlation between the spikes numbers and the tiller number (r = 0.872). The salinity affected negatively these two parameters, which both initiate during early growth stages. So, the salinity has a greater influence on final grain yield than on yield components in the later stages. The studied parameters showed significant differences (p<0.05) between the barely accessions.The cluster analysis using agronomic parameters at all growth stage showed that the accessions "Ettalah" and "Elhezma" were ranked as the most tolerant to salinity. However, "Boughrara" and "Edwiret Elgdima" accessions were ranked as moderate and presented a change of their degree of tolerance with the different growth stage. The remaining accessions showed the lowest tolerance to salinity. A highest tolerance was observed on the accessions from plain zones compared at those of mountainous zones.The response differences between accessions of local population of barley "Ardhaoui" reflecting an important internal genetic variability against the salinity. This variability could be more explored and used for the barley breeding program.

Effects of salinity, temperature and their interactions on the rate and final percentage of germination were evaluated for two populations (Msarref, Oued dkouk) of the invasive glycophyte Lotus creticus Linné, grown under arid environmental conditions of the Tunisia. Seeds that were not treated with NaCl germinated well in a wide range of temperatures. For both populations, maximum germination occurred in distilled water at 25°C and lowest germination for all salinities was at 35°C. Germination was substantially delayed and significantly reduced with an increase in NaCl to levels above 300 mm. Compared to the Oued dkouk population, final germination and germination rate of the Msarref population was completely inhibited at 300 mm NaCl. The interactive effect of temperature and NaCl concentration on final germination and germination rate was significant (P < 0.01), indicating that the germination response to salinity depended on temperature. The inhibition of Oued dkouk population seed germination at high salt concentration was mostly due to osmotic effects while ionic effects were noted at Msarref population. The germination behaviour of the Oued dkouk population would therefore imply adaptive mechanisms to saline environments, while in the Msarref population such mechanisms seem to be absent. Since seed germination is more sensitive to salinity stress than the growth of established plants, the greater tolerance to salinity of Oued dkouk population would be an adaptive feature of this population to saline environment.