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The present paper described the first green synthesis of silver nanoparticles (AgNPs) from the extremophile plant Aeonium haworthii. The characterization of the biosynthesized silver nanoparticles was carried out by using UV-Vis, FTIR and STM analysis. The antioxidant, antidiabetic and antimicrobial properties were also reported. The newly described AgNPs were spherical in shape and had a size of 35–55 nm. The lowest IC50 values measured by the DPPH assay indicate the superior antioxidant behavior of our AgNPs as opposed to ascorbic acid. The silver nanoparticles show high antidiabetic activity determined by the inhibitory effect of α amylase as compared to the standard Acarbose. Moreover, the AgNPs inhibit bacterial growth owing to a bactericidal effect with the MIC values varying from 0.017 to 1.7 µg/mL. The antifungal action was evaluated against Candida albicans, Candida tropicalis, Candida glabrata, Candida sake and non-dermatophytic onychomycosis fungi. A strong inhibitory effect on Candida factors' virulence was observed as proteinase and phospholipase limitations. In addition, the microscopic observations show that the silver nanoparticles cause the eradication of blastospores and block filamentous morphogenesis. The combination of the antioxidant, antimicrobial and antidiabetic behaviors of the new biosynthesized silver nanoparticles highlights their promising use as natural phytomedicine agents. [ABSTRACT FROM AUTHOR]

Polyphenol's extraction varied according to various factors. In this study, the effect of genotype and method of polyphenols extraction were investigated using leaves of two cultivated and two wild olive varieties and four hydromethanolic extraction methods. Quantitatively, significant differences were observed according to the extraction method, the genotype, and the interaction genotype-method of extraction. The heat reflux extraction showed the highest polyphenols content in wild olive leaves having an amount of 841.17 mg GAE/100 g DM. The qualitative phytochemical examination using high performance liquid chromatography (HPLC) of olive leaves showed some significant differences of phenolic compounds between genotypes. For the same oleaster genotype, the extraction method seemed to influence qualitatively the polyphenols profiles. The quinic acid was the dominant phenolic acid and the luteolin-7-Oglucoside was the major flavonoid observed in wild olive leaves having, respectively, 618.24 and 3211.44 mg/kg DM. The quinic acid has an amount of 400.15 and 275.39 mg/kg and the luteolin-7-O-glucoside has an amount of 2059.62 and 1214.49 mg/kg in cultivars leaves. The extraction by Soxhlet of wild olive leaves showed the highest quinic acid (1085.80 mg/kg DM) and luteolin-7-O-glucoside (3720.15 mg/kg DM) amounts. The hydromethanolic extraction assisted by Soxhlet of wild olive leaves constituted the optimal method to obtain high polyphenols contents enriched with phenolic acids and flavonoids. [ABSTRACT FROM AUTHOR]

This study addresses the processing limitations of camel milk for production of textured camel milk cheese by utilising the green carob extract (GCE) as a novel coagulant. The response surface methodology was employed to assess the impact of GCE on the cheese quality parameters. Maximal soft camel cheese yield (24.1%) was achieved using 12% (v/v) of GCE, coagulation at 53.6°C, and incubation time of 9 h 52 min. Compositional analysis revealed the richness of soft camel cheese in dry matter (33.8 ± 81.61%), carbohydrates (3.66 ± 0.45%), and calcium (632.83 ± 68.43 mg/100 g). The addition of GCE enhanced the cheese's flavour and texture. [ABSTRACT FROM AUTHOR]

Abstract Background Oilseed samples from four Acacia species ( A. cyclops, A. ligulata, A. salicina and A. cyanophylla) were analyzed in order to evaluate the potential nutritional value of their unexploited seeds. Methods Samples were collected from different Tunisian geographic locations. Seed oils were extracted and carotenoids, tocopherols and sterols were analyzed using chromatographic methods. Results The studied Acacia seeds seem to be quite rich in lipids (from 6% to 12%). All Acacia species contain mainly the xanthophylls zeaxanthin and lutein compounds: from ca. 38 mg.kg-1 of total lipids (A. cyclops) to ca. 113 mg.kg-1 of total lipids (A. cyanophylla). Total tocopherols varied from ca. 221 mg.kg-1 of total lipids (A. cyclops) to ca. 808 mg.kg-1 of total lipids (A. ligulata). Sterols are highly present and their contents ranged between ca. 7 g. kg-1 of total lipids (A. salicina) and 11 g. kg-1 of total lipids (A. cyclops). Conclusion This study highlights that these unexploited seeds might have a potential nutritional value and encourages researchers to more explore and find developments for these plants for healthy purposes.

There is a growing need to develop an effective process for improving the oxidative stability of edible oils using natural antioxidants. Central composite design of experimental measurements was used to investigate the effects of three process variables (weight of dried powdered oleaster leaves, volume of olive oil, and maceration time) on olive oil enrichment with oleaster (wild olive trees) leaves. By solving the regression model equations and analyzing three-dimensional response surface plots, the optimum conditions were determined for the polyphenol, chlorophyll and carotenoid contents and for the antioxidant activity using 2, 2 diphenyil-1-picrylhydrazyl (DPPH) and 2, 2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS) assays. The optimal conditions were 7.76 g of dried powdered oleaster leaves, 116.44 mL of olive oil and 41.82 h for the maceration time. High polyphenols (354.95 mg/kg), chlorophylls (8.13 mg/kg) and carotenoids (1.51 mg/kg) were determined to be optimism. High-performance liquid chromatography analysis showed that the enrichment process improved the phenolic profile of the enriched olive oil. Furthermore, the DPPH and ABTS activities were 427.30 and 738.50 mg TEAC/kg oil, respectively. The experimental measurements agreed with the predicted values. Oleaster leaves have great potential to be applied as natural sources of bioactive molecules for edible oil processing. [ABSTRACT FROM AUTHOR]

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]

Olive oil is rich in natural antioxidants that conserve its quality under storage conditions. However, there is a growing need to improve the quality of olive oil under storage conditions using phenol-enriched olive oil. In the present study, olive oil from the Chemlali cultivar was enriched with wild olive tree leaves or oleaster. The oil composition was analyzed before and after accelerated storage conditions using a Schaal test. Standard oil parameters, including free acidity; peroxide value; iodine value; specifc extinction K232 and K270; fatty acid profle, and polyphenolic, chlorophyll, and carotenoid content, were evaluated for the control olive oil (COO) and the enriched olive oil (EOO). Polyphenolic compounds were identifed for COO, EOO, and oleaster leaf extracts (OLE) using high-performance liquid chromatography. Antioxidant activity was analyzed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’ azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) tests. The results showed that enriching the olive oil quantitatively and qualitatively improved the polyphenolic composition, pigment contents, and the antioxidant activity. The EOO was more resistant to oxidation under accelerated storage conditions. The addition of wild olive leaves also signifcantly improved the resistance of the olive oil to oxidation and can, therefore, be used as a source of natural antioxidants to improve the oxidative stability of edible oils. [ABSTRACT FROM AUTHOR]

The present study aims to assess the nutritional quality and the antioxidant capacity of (Punica granatum L. 'Gabsi') and date (Phoenix dactylifera L. 'Bouhattam') juices and their combination at three proportions (PPD 2:1, PD 1:1, and PDD 1:2). This investigation revealed the interesting potentialities in terms of bioactive molecules, natural antioxidants, and high organoleptic characteristics of various prepared juice formulations. For all juices, the sugar contents were averaged to 16°Brix. The highest monosaccharide content was obtained at the pomegranate/date juice (PDD) (glucose: 9.52 ± 0.88 g/100 ml, fructose: 9.91 ± 0.44 g/100 ml). The comparative study of the five juice formulations based on phenolic contents showed that they are loaded with phenolic compounds. Indeed, the PD juice had the highest polyphenols content (10.77 mg GAE/ml of juice); however, the pomegranate juice had the highest flavonoids content (5.71 mg RE/ml of juice). The assessment of the antioxidant activity was conducted based on three methods: ferric reduction power, DPPH°, and ABTS+ assays. Our results confirmed that all juices were loaded with natural antioxidants. Moreover, the sensorial test of the five juice formulations showed an acceptable quality by the tasting panel. To conclude, this study reveals that the formulation of a cocktail pomegranate/date juice seems to be an interesting initiative for the processing of noncommercial varieties. [ABSTRACT FROM AUTHOR]