Background:Rhamnus alaternus (Rhamnaceae) L. has been traditionally used for treatment of many diseases.Objective:In this study, we determined the antioxidant/free radical scavenger properties, the flavonoid profile and the cytotoxicity of aqueous and methanolic extracts obtained by maceration from Algerian R. alaternus bark, like also of aqueous extract prepared by decoction according to the traditional method. This to estimate the usefulness of the drug traditional preparation and compare it with those made in the laboratory.Materials and Methods:The antioxidant activity of the extracts was evaluated using five different redox-based assays, all involving one redox reaction with the oxidant. High-performance liquid chromatography/diode array detection/electrospray ionization mass spectrometry analysis was used to identify and quantify the flavonoids content. Cytotoxicity on human monocytic leukemia cells (U937) was also carried out.Results:All the extracts tested showed a good antioxidant/free radical scavenger activity and a similar flavonoid fingerprint. However, the methanolic one presented the best antioxidant activity that can be due to the highest flavonoid amount and significantly reduced the proliferation of leukemia cells. The results confirm that the extract prepared by decoction contains efficient antioxidant compounds and this justifies in part the therapeutic and preventive usefulness. Moreover, the methanolic extract exerted excellent cytotoxicity on U937 that could be attributed to kaempferol and rhamnocitrin glycosides.

In Algeria, the olive tree is one of the main fruit species and plays a very important socioeconomic role. The objective of this study was firstly, to identify and quantify the phenolics of some Algerian olive oils, and secondly, to assess the antioxidant activity of the samples. The olive oils used in this study were derived from Algerian cultivars, including Tefahi, Gelb Elfarroudj, Chemlal, and imported cultivar Manzanilla and Zebboudj. For this purpose, gas chromatography—mass spectrometry (GC-MS) was used to identify olive oil fatty acids profile, while the individual phenolic compounds were assessed by ultra-high-performance liquid chromatography–electrospray ionization–high-resolution mass spectrometry (UHPLC-HESI-MS). To verify the antioxidant capacity, five in vitro free radical assays were used. Questionable values of particular physico-chemical parameters, such as the high value of free acidity and the low concentration of monounsaturated fatty acids in oil from the Zebboudj cultivar, indicate that improvements in olive cultivation and oil production practices are needed. Gelb Elfarroudj, Tefahi, and Manzanilla oils contain quantities of monounsaturated fatty acids in accordance with EU regulations. The oil obtained from the Zebboudj cultivar is not usable for food purposes due to the high value in free acidity and the low concentration of monounsaturated fatty acids. Tefahi and Manzanilla cultivars have given oils with the best antioxidant activity as compared to other studied cultivars; this is attributable to their composition in bioactive phenolic compounds, such as secoiridoids, which play an important role in human health as scavengers of free radicals. The results are interesting for producers and consumers to promote the culture of olive oils derived in particular from the Tefahi cultivar. However, in order to improve the health qualities of this oil, the agronomic techniques essentially linked to the time of harvesting of the olives destined for oil production must be improved.

Retama sphaerocarpa occurs in the Mediterranean area of North-east Africa and in the Iberian Peninsula, and grows on a variety of soil types and climatic conditions. Used in Algerian folk medicine, it is a valuable species for revegetation and soil restoration. The aim of this study is to evaluate flavonoid composition and antioxidant and antiglycation properties of methanolic and aqueous extracts from R. sphaerocarpa fruits. HPLC-PDA/ESI-MS was used to identify/quantify flavonoid content. Antioxidant activity was evaluated by Folin-Ciocalteu, ORAC, FRAP, TEAC, and DPPH assays, and antiglycation capability by glucose/fructose-BSA assay. Results showed that fruits contain isoflavones (daidzein and genistein derivatives) and flavonols (apigenin, isorhamnetin, kaempferol and quercetin derivatives), and extracts (especially the methanolic one, richer in flavonoids) possess good in vitro antioxidant and antiglycation properties. These findings evidence that R. sphaerocarpa fruits are a source of valuable phytochemicals, with potential applications in the field of phytopharmaceuticals and in food industry.

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