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Fabaceae seeds are reported to be used for varying medicinal and pharmaceutical purposes. However, knowledge of the nutritive value of Astragalus tenuifoliosus seeds is largely based on very limited data and remains unexplored, we report here the protein content, phenolics as well as the antioxidant potential of plant seeds to give adequate information on its suitability as a new source of natural bioactive compounds. The protein content was determined using the Kjeldahl and Bradford assays. The phytochemical contents were evaluated, and the extracts were further subjected to high-performance liquid chromatography-electrospray ionization – mass spectrometry (HPLC-ESI-MS) analysis. The antioxidant potential was evaluated using the total antioxidant capacity and the free DPPH radical scavenging activity. The results obtained from the protein analysis showed that the total content was 59.43 % of the dry matter basis. The globulins constituted the dominant fraction and followed by albumins, glutelins, and prolamins. The phytochemical investigation showed considerable amounts of polyphenol, flavonoid and condensed tannin amounts. The LC-ESI/MS analysis revealed the presence of 18 phenolics including 8 phenolic acids and 10 flavonoids mostly predominated by quinic acid (255.4 µg g-1 DW), p-coumaric acid (65.39 µg g-1 DW), quercetin (97.21 µg g-1 DW), and cirsiliol (29 µg g-1 DW). The seeds possessed strong antioxidant potential evidenced by their DPPH radical scavenging activities and total antioxidant capacity. The obtained findings contribute to the limited bibliographic information concerning A. tenuifoliosus seeds and represent a starting point to evaluate its potential as a valuable source of proteins, natural antioxidants, and safe bioactive compounds. Resumen. Las semillas de las Fabaceae se utilizan para diversos fines medicinales y farmacéuticos. Sin embargo, el conocimiento del valor nutritivo de las semillas de Astragalus tenuifoliosus se basa en gran medida en datos muy limitados y sigue sin explorarse. Aquí se reporta el contenido de proteínas, fenoles y el potencial antioxidante de las semillas de plantas para brindar información adecuada sobre su idoneidad como nueva fuente de compuestos bioactivos naturales. El contenido de proteína se determinó utilizando los ensayos de Kjeldahl y Bradford. Se evaluaron los contenidos fitoquímicos y los extractos se sometieron a análisis de cromatografía líquida de alto rendimiento, ionización por electropulverización y espectrometría de masas (HPLC-ESI-MS). El potencial antioxidante se evaluó utilizando la capacidad antioxidante total y la actividad de captación de radicales libres DPPH. Los resultados obtenidos del análisis de proteína mostraron que el contenido total fue de 59.43% con base en el peso seco. Las globulinas constituyeron la fracción dominante, seguidas por las albúminas, las glutelinas y las prolaminas. La investigación fitoquímica mostró cantidades considerables de polifenoles, flavonoides y taninos condensados. El análisis medinate LC-ESI/MS reveló la presencia de 18 fenoles, incluidos 7 ácidos fenólicos y 11 flavonoides, predominando en su mayoría el ácido quínico (255.4 µg g-1 DW), el ácido p-cumárico (65.39 µg g-1 DW), la quercetina (97.21 µg g-1 DW), y el cirsiliol (29 µg g-1 DW). Las semillas poseen un fuerte potencial antioxidante, evidenciado por sus actividades de eliminación de radicales DPPH y su capacidad antioxidante total. Los hallazgos obtenidos contribuyen a la limitada información bibliográfica sobre las semillas de A. tenuifoliosus y representan un punto de partida para evaluar su potencial como fuente valiosa de proteínas, antioxidantes naturales y compuestos bioactivos seguros.

Quantification of germination niches under salt stress, temperature, and their interaction using population-based threshold models is important to predict seedling emergence patterns. Seeds of Sarcocornia fruticosa, Sarcocornia alpini, and Salicornia emerici were treated with various temperatures at different NaCl concentrations. Results indicated that the median base NaCl concentration was roughly steady (0.68, 0.73, and 0.70M, respectively) at sub-optimal temperature, then decreased linearly at supra-optimal temperature until the ceiling temperature (Tc). The estimated base, optimum and ceiling temperatures, in water, were − 0.5, 15 and 29°C for Sarcocornia fruticosa, − 2.5, 11 and 24°C for Sarcocornia alpini, and 9.5, 25 and 40°C for Salicornia emerici, respectively. At all species, the base temperature has not changed with the salinity while both optimum and ceiling temperatures decreased. Also, Salicornia emerici showed rapid and synchronized germination when salinity decreases during the rainy season coinciding with favorable temperatures compared with other species.

The design of the current study was to determine the functional properties of P. maritimum seeds by evaluating their mineral content, fatty acid composition, and biactive compounds. Results showed that seeds contained remarkable amounts of Na, K, Ca, Mg, Cu, Zn, and Fe. The oil yield was found to be 4.58% and contained higher unsaturated fatty acids predominated by linoleic and oleic acids. The colorimetric investigation revealed high total polyphenol (33.56 mg gallic acid equivalent/g), flavonoid (46.3 mg quercetin equivalent/g), and condensed tannin (22.3 mg catechin equivalent/g) contents. Furthermore, the LC-ESI/MS analysis revealed the presence of 13 phenolics mostly predominated by (+) catechin, quercetin-3-O-galactoside, gallic acid, and quinic acid. The seeds possessed strong antioxidant potential evidenced by ABTS and DPPH radical scavenging activities, total antioxidant capacity, and reducing power. The present findings suggest that P. maritimum seeds may be used as a potential source of biologically active natural products.

Periploca angustifolia (Labill.) is a multipurpose xerophytic shrub widely distributed in arid zones. It is used in rehabilitation programs; its exploitation and utilization require the understanding of its behavior under stress conditions such as drought. To evaluate drought response and at what level it becomes irreversible, a new analysis of physiological and biochemical performances of this threatened shrub was conducted to assess possible mechanisms of drought tolerance and how these relate to its ecological success. Eleven-month-old plants, grown under semi-controlled conditions, were subjected to a well-watered control treatment or progressive drought by withholding water for 7, 14 and 21 d with subsequent recovery for 7-d. After 7 days of drought, followed by rewatering period, no significant effect on all studied parameters was recorded for P. angustifolia . However, from 14 until 21 days of withholding irrigation, drought becomes irreversible causing plant damages, may be rewatering has no effect to reduce these damages. A water deficit of 21 days RWC (33%), chlorophyll a content (0.083 mg·g − 1 DW), transpiration 14.7%, as well as water and osmotic potential (− 3.40 and − 3.78 MPa) decreased significantly compared with control. While, proline content (0.25 μmol·g − 1 FW), soluble sugars (80.52 mmol·g − 1 DW) and vitamins C, E (1.9 mM·g − 1 FW) increased significantly that could indicate ability of osmotic adjustment in this species. Also the increases in RWC, water and osmotic potentials values after rewatering period indicate the good recovery of this plant. Based on these experiments, responses of P. angustifolia to water stress were typical of those of xerophytic plants.

Polygonum is the largest genus of Polygonaceae and 5 species are reported in Tunisia. In order to characterized flower, seed, and fruit development in Polygonum, flower and fruit of Polygonium equisetiforme (var. graecum and peyerinhoffi), P. aviculare and P. maritimum, collected from Tunisia, were examined. Flowers are composed of five oblong tepals. P. equisetiforme and P. aviculare have whitish-pink distylous flowers with dimorphism of style, filament and anther height, pollen diameter and stigma size. In contrast, P. maritimum shows white homostylous flowers. The floral vasculature showed that the tepals are inserted in one whorl and their traces arise independently in 3+2 manner. The eight stamens are arranged in a 5+3 manner and the staminal bundles arise independently in the two whorls. The epidermis and endothecium cells width were higher in P. maritimum and the lowest endothecium width was observed in P. aviculare. Polygonum aviculare and P. equisetiforme showed circular pollen with shallow colpi and trilobite pollen shape with deep colpi, while P. maritimum rarely showed shallow colpi. The ovule is anatropous with basal placentation in P. equisetiforme and P. aviculare and apical placentation in P. maritimum. The young seed coat was formed by an endotesta with thick-walled cells, a mesotesta and exotesta with thin-walled cells and a tegmen composed of radially elongated cells. The fruits of the studied species are trigonous with ovate-lanceolate shape. In P. aviculare, the exocarp is thicker compared to the two other species, in P. equisetiforme, the mature exocarp consists of smaller rectangular cells with narrow cavities, and in P. maritimum showed a thinner exocarpIn conclusion, P. equisetiforme and P. aviculare are a typically distylous species from the morphological point of view and we discussed the significance of heterostyly in Polygonaceae. From this first morpho-anatomical study of Polygonum species in North Africa, we can conclude mainly that there is no significant difference between P. equisetiforme var. graecum and var. peyerinhoffi supporting a taxonomic grouping of these two varieties.

The present study was designed to study the effect of drought on root, stem and leaf anatomy of Astragalus gombiformis Pomel. Several root, stem and leaf anatomical parameters (cross section diameter, cortex, root cortical cells, pith, leaf lamina and mesophyll thickness) were reduced under moderate to severe water deficit (20–30 days of withheld irrigation). The stele/cross section root ratio increased under moderate water deficit. The root’s and stems vascular systems showed reduced xylem vessel diameter and increased wall thickness under water deficit. In addition, the root xylem vessel density was increased in these drought conditions while it was unchanged in the stems. The stomata density was increased under prolonged drought conditions whereas the stomata size was untouched. The leaf vascular system showed reduced xylem and phloem tissue thickness in the main vein under moderate to severe water deficit. However, in the lamina the vascular tissue and the distance between vascular bundle were unaffected. Our findings suggest a complex network of anatomical adaptations such as a reduced vessel size with increased wall thickness, lesser cortical and mesophyll parenchyma formation and increased stomata density. These proprieties are required for the maintenance of water potential and energy storage under water stress which can improve the resistance of A. gombiformis to survive in arid areas.

This study was carried out to evaluate the effect of long-term natural aging on germination ability and several biochemical characteristics regarding soluble sugars and polyphenol matter contents and radical scavenging activity of Periploca angustifolia Labill. (Asclepiadaceae) stored seeds for 1, 3, 7, 10, 11 and 15-years, dry storage compared to freshly collected seeds. The long-term aging caused an important decrease of germination percentage, seed vigor index, seeds’ viability, moisture content and seed vigor except for seeds stored for seven-years. The latter showed the highest percentages of germination and viability, seed vigor index and seed vigor under a 7.3% moisture content when compared to the oldest seeds (15-years old) which presents the lowest moisture content. In our study, aged seeds showed the lowest radical scavenging percentage activity and amounts of polyphenol, keeping free radicals and peroxides at high levels causing thereby seeds deterioration. P. angustifolia seeds undergo a process of after-ripening under the storage conditions, possibly depending on the low, but steady water loss down to an optimal storage water content of approx. 7.3%, thereafter undergoing some deterioration as indicated by reduced amounts of soluble sugars by polyphenol contents and experimentally tested antioxidant activities, which is in line with increased membrane leakages as indicated by increased electrical conductivities of solution from experimentally soaked seeds. Keywords : Periploca angustifolia Labill, polyphenol, germination African Journal of Biotechnology Vol. 12(15), pp. 1760-1768

Aegilops geniculata Roth (Poaceae) is a potential source of genetic variation for wheat improvement. In order to distinguish and evaluate different genetic of Aegilops and Triticum using RAPD markers, thirteen Aegilops geniculata populations and three durum wheat varieties (Triticum durum Desf.) were collected from different regions of Tunisia (North and central). Aegilops geniculata Roth populations (Goussa, Djebel Abderahmen, Tabarka, Djebel Ressas), (Bizerte, Zaghouan), (Mekna, Ain Zana), (Djebel Oust, Souk jemaa, Sbeitla), (Djebel Serj, Nefza) constitute different groups. Complement gene locus were amplified by nineteen RAPD primers witch produced 212 bands, that 182 bands (about 86%) were polymorphic. The results revealed that genetic diversity within populations was relatively high. Nei’s genetic diversity (H) and Shannon’s index (I) were 0.324, 0.484 respectively. Global AMOVA showed that genetic variation within populations accounted 80% occurring (ΦPT =0.205 p

A collection of nine Tunisian faba bean (Vicia faba) populations belonging to three botanical classes (Var. minor, var. equina and var. major) was evaluated using twenty seven agro-morphological traits. Analysis of variance, correlation coefficients and principal components analysis (PCA) were performed based on MVSP 3.13 program. Significant differences between populations were noted for most agromorphological traits in four main groups. The first group, positively correlated to the two axes, isrepresented by ‘Bachaar’ belonging to V. faba. var. minor, the second group, including V. faba. var. minor population (‘Massri’ and ‘Badï’), is positively correlated to the PC1 and negatively correlated to the PC2 while the third group, is composed of two V. faba var. major (‘Malti’ and ‘Batata’) and were positively and negatively correlated to the PC2 and PC1, respectively. Finally, the fourth group negatively correlated to the two axes, gathers the remaining population (‘Chahbi’, ‘Chemlali’, ‘Aguadulce’ and ‘Super Aguadulce’). The dendrogram based on Nei's genetic distance of the 9 populations using UPGMA method, show some genetic drift between populations.Key words: Faba bean, agromorphological traits, principal components analysis, UPGMA method.

This study used sequence specifc amplifcation polymorphism (SSAP) markers to investigate the genetic diversity and population genetic structure of nine Tunisian Vicia faba populations belonging to the minor and major faba bean’s sub-species. Three primers were used (PDR1, Tps19 and Tvf4) in this study. These primers gave good SSAP marker profiles, high number of bands obtained per gel and a high percentage of polymorphic bands as confirmed in a previous study. Indeed, these primers provided a total of 173 amplified bands, with 123 of them being polymorphic. Shannon indexes ranges from 0.166 to 0.248 with an average of 0.207. The genetic diversity within population of 0.743 was clearly higher than that of among population genetic diversity (Dst = 0.138), indicating an out-crossing predominance in the studied populations. The Dst value showed that 15.6% of the total genetic variation resided among populations, a little lower than that of out-crossing species. The dendrogram grouping the populations by unweighted pair-group method with arithmetic averages (UPGMA) method revealed three main clusters. The local major faba bean ‘Batata’ was the most divergent population and was separated from other population.Key words: Vicia faba, SSAP marker, Genetic diversity, Tunisia.

Seven isozyme systems (Sod, 6-Pgd, Me, Est, Skdh, Fdh and Gdh) representing nine loci were used to study the genetic diversity of nine faba bean populations. Seven loci revealed polymorphic bands and showed the same quaternary structure as that found in several species. They revealed a high number of phenotypes. Indeed, from 3 to 9 phenotypes per locus were investigated in this study. The percentage of polymorphic loci (P = 59.3 %) was higher than that mentioned in the autogamous species (P = 20.3 %) and less than the optimum (P=96 %) indicated for allogamous plants. Total genetic diversity (H T) and within population genetic diversity (H S) were estimated with the isozyme markers. The contribution of among population genetic diversity (D ST) to total genetic diversity was 22%. Enzyme markers pointed out an average inbreeding level for whole population (F IT) and within population (F IS). Within population genetic diversity represents 78% of total diversity. Intra-population genetic diversity (H S = 0.206) was ranged with the respect of allogamous species and was clearly higher than that of among population genetic diversity (D ST = 0.057) indicating an out-crossing predominance in the studied populations. The expected heterozygosity was higher than that observed heterozygosity at the allogamous species was confirmed in this study. Although, the mean estimated gene flow was less than 1(Nm=0.814), the dendrogram based on Nei's genetic distance of the 9 populations using UPGMA method showed some genetic drift between populations. © 2011 The Genetics Society of Korea and Springer Netherlands.