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In this study, the phytochemical profile including the fatty acids composition and the minerals, the polyphenols, and the proteins contents were quantified on leaves, pulp, and stone of two oleasters trees from southern Tunisia. Two olive cultivars (Zarrazi and Chemlali) were used for comparisons. The antioxidant activities were conducted using the 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and the 2,2-diphenylpicrylhydrazyl (DPPH) assays. Results showed that the pulp and the stone of oleasters (wild olives) were richer in total lipid having, respectively, 16.30% and 9.42% of Dry Weight basis (DW). Qualitatively, the fatty acids profile of pulp and stone from cultivars and oleasters was identical. The oleic acid is the major fatty acid having the highest percentage in the oils from the stone of oleaster1 (69.08%) followed by linoleic acid. However, quantitatively, significant differences in fatty acids composition were noted. The oleaster stones were richer in storage proteins showing that the globulin is the major fraction (50.47%), followed by albumin (25.72%), prolamin (17.61%), and glutelin (6.19%) fractions. Concerning the minerals, results showed that the pulp is richer in potassium (862.87 mg/100 g DW) than leaves (526.50 mg/100 g DW) and stone (136.50 mg/100 g DW). In contrast, the leaves have the highest phosphorus content (42.74 mg/100 g DW). The highest polyphenols content was 711.55 mg/100 g DW in the pulp followed by the leaves and stone. The leaves, pulp, and stone extracts showed high antioxidant activities using DPPH and ABTS assays. The oleasters seem to be a potential source of edible oil, protein, and antioxidants. They could be used as supplements and/or ingredients in oil and fat industries. [ABSTRACT FROM AUTHOR]

The olive tree is represented in Tunisia by two varieties: var. sylvestris (wild olive trees) and var. europaea (cultivated olive trees including diverse cultivars). Seed (stone) size and shape analysis may provide the basis for relationships between varieties and cultivars as well as to study the responses to environmental conditions. A semi-automated method of image analysis allows to obtain data related with magnitudes descriptive of stone size and shape and to compare between wild and cultivated olives. Also, the effect of bioclimate on size and shape was analyzed in some cultivars. Stone size and shape presents high variability. In cultivated trees stones are larger. Mean seed image area is 0.38 and 0.75 cm2 for wild and cultivated plants respectively. Roundness and circularity were compared as to their potential to define seed shape. Mean values were higher for circularity, but roundness is more variable reaching higher values in some individuals and varieties. Roundness is more useful to compare seed shape variations. In addition, climate factors affect the stone characteristics in cultivars; those of sub-humid region having larger stones. Phenotypic parameters of stone are discriminating parameters for the analysis of intra-specific, intra-varieties and intra-cultivars variability in Olea europaea. [ABSTRACT FROM AUTHOR]

The wild olive trees or oleaster (var. sylvestris) and the cultivated olive trees (var. europaea) constitute the two botanical varieties of Olea eutvpaea L. from Mediterranean. In this study, a partial chemical profile was conducted including the total lipids, the fatty acid profiles, soluble proteins, polyphenols, flavanoids contents and antioxida activities of stone from six oleaster trees. The comparison was made by two olive cultivars cultivated in the same region. The oleaster and cultivar stones were richer in oil content having an average of 8.99 and 7.38 % dry weight basis (DW), respectively. Qualitatively, all studied oils have the same fatty acids profile with the oleic acid C18:1n-9 as the major fatty acid. The oleaster stone oils were richer in monounsaturated fatty acids having an average of 64.87%. They, also, richer in protein content with an average of 198.86 mg/g DW. The globulin is the major fraction, followed by the albumin the prolamin and the glutemin fractions. The oleaster stone extracts contain polyphenols, flavonoids with an average of 151.14 and 11.91 mg gallic acid equivalent/100g of DW, respectively. The studied extracts showed antioxidant activity using the free radical scavenging activity determined by DPPH and ABTS. The unexploited oleaster stone seems to be a source of oil with good fatty acids balance, in protein and antioxidants metabolites and would be useful for the formulation of supplements and/or pharmaceutical ingredients. [ABSTRACT FROM AUTHOR]

Abstract: Olive cultivars are diversified but nothing is known on their origins and if they are local or introduced in any regions. The study aims to determine which traits may help to identify native from introduced cultivars and oleaster trees. We compared cultivars and oleasters from North Tunisia to determine their relationships based on morphological traits, oil composition and SSR genotyping at seven loci. We used those parameters to examine 32 cultivar trees from 17 denominations and 70 oleaster trees sampled. We used multivariate analysis, enabling to retain the best variables, to establish relationships among trees based on morphological and pomological parameters. Gas chromatography was used to determine fatty acid composition of 30 cultivar trees and 13 oleaster trees. We determined for one cultivar Gerboui the steady drupe, pit morphological and oil composition variation ranges in six different contrasted agro-systems. SSR genotyping was performed in polyacrylamide gels after fluorescent labelling. Based on morphology, oleaster trees from agro-ecosystems clustered broadly in an intermediate position between cultivars and oleasters from natural ecosystems. SSR revealed that the feral and genuine oleasters plus cultivars are always overlapping. Relationships between cultivars are displayed in two dendrograms. They revealed six and three main clusters based on Unweighted Pair Group Method (UPGMA) and Ward algorithm, respectively. They mix olive cultivar and oleaster trees suggesting kinship relationships between some cultivar and some oleaster trees. In contrast, on PCA, some morphological parameters split our sample approximately between olive and oleaster trees. Oil composition was similar between cultivar and oleaster trees. Kinship relationships between cultivar and oleaster trees based on molecular polymorphisms suggested that olive cultivars may have origin in local oleasters. Oil composition as fruit descriptors and drupe size appeared inefficient to discriminate between olive and oleaster trees, in comparison to SSR. Our results suggested several domestication events for the olive. It is important to know which cultivars have local origin to promote and sale products from Tunisia as from all around the Mediterranean basin. [Copyright &y& Elsevier]