Leafy Stems of Phagnalon saxatile subsp. saxatile from Algeriaas a Source of Chlorogenic Acids and Flavonoids with Antioxidant Activity: Characterization and Quantification Using UPLC-DAD-ESI-MSn.

Phagnalon saxatile subsp. saxatile is a wild species widespread in Algeria which is utilized for medicinal purposes as analgesic and anticholesterolemic. However, information is still scarce regarding its phytochemical content. The objective of this study was to identify and quantify the phenolic compounds from different extracts of its leafy stems. For this purpose, the effects of four extracting solvents were investigated on the content of phenolic compounds and the antioxidant activity of this plant. The extracts prepared with polar solvents (methanol and water) contained higher amounts of phenolic compounds and showed better antioxidant activity than the extracts with apolar solvents (hexane, dichloromethane). The methanolic extract, richest in total phenolic and total flavonoid, had significant antioxidant activity as regarded by DPPH° scavenging capacity (IC50 of 5.5 µg/mL), ABTS+° scavenging capacity (IC50 of 63.8 µg/mL) and inhibition of oxidation of linoleic acid (IC50 of 22.7 µg/mL), when compared to synthetic antioxidants. Chlorogenic acids and several flavonoids were identified and quantified by UPLC-DAD-MSn. The di-O-caffeoylquinic acids isomers were the most concentrated phenolics (25.4 mg/g DW) in the methanolic extract.

Antioxidant activity profiling by spectrophotometric methods of aqueous methanolic extracts of Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile.

AIM: The aqueous methanolic extracts of two plants from Algeria, Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile, were investigated for their antioxidant activity. METHOD: Total phenolics, flavonoids, and tannins were determined by spectrophotometric techniques. In vitro antioxidant and radical scavenging profiling was determined by spectrophotometric methods, through: Total antioxidant capacity, and radical scavenging effects by the DPPH and ABTS methods, reducing and chelating power, and blanching inhibition of the ß-carotene. RESULTS: All of the extracts showed interesting antioxidant and radical scavenging activity. The highest contents in phenolics, tannins, and the highest total antioxidant capacity as gallic acid equivalents of 97.5 ± 0.33 mg GAE/g DW was obtained for the flowers of H. stoechas subsp. rupestre extract in the phosphomolybdenum assay. An extract of the leafy stems of P. saxatile subsp. saxatile revealed the highest content of flavonoids, and the highest antioxidant activity by the radical scavenging and ß-carotene assays when compared with standards. The best activity was by the scavenging radical DPPH with an IC50 value of 5.65 ± 0.10 µg·mL(-1). CONCLUSION: The studied medicinal plants could provide scientific evidence for some traditional uses in the treatment of diseases related to the production of reactive oxygen species (ROS) and oxidative stress.

Evaluation of antioxidant activity of hydromethanolic extracts of some medicinal species from South Algeria.

BACKGROUND: Phytochemicals are found in abundance at different levels in many medicinal plants. It is important to measure the total phenolic compounds correctly in such medicinal plants, the better to assess their antioxidant capacity. METHODS: Our study sought to evaluate the total phenolic, flavonoid, and tannin contents of three Algerian medicinal plants: Echium pycnanthum Pomel, Haloxylon articulatum Boiss, and Solenostemma oleifolium Bull. & Bruce. We employed six different testing methods to help ascertain whether these compounds have an antioxidant capacity, including total antioxidant capacity, 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid(+), ß-carotene, reducing, and chelating assays. RESULTS: Our study showed that these medicinal plants exhibited significantly different total polyphenol contents varying from 27.3 ± 2.1 mg to 120.3 ± 5.6 mg gallic acid equivalents/g dry weight. The phenolic content in H. articulatum was superior to those in E. pycnanthum and S. oleifolium. The same tendency was observed for the relative amounts of flavonoids and condensed tannins in the three medicinal plants. The antioxidant activities varied greatly among the different plants used in this study. Indeed, H. articulatum shoots exhibited the strongest antioxidant activity, with the lowest IC50 (6.3 ± 0.25 µg/mL) and EC50 (0.21 ± 0.01 mg/mL) values for 1,1-diphenyl-2-picrylhydrazyl and iron reducing tests, respectively. In addition, the superiority of this plant was more marked as compared to positive controls. Strong and positive correlations were found between phenolic classes and antioxidant activities with a correlation coefficient reaching R ≥ 0.99. CONCLUSION: This investigation confirmed that several medicinal herbs from South Algeria possess high in vitro antioxidant potency. Overall, our results can be considered very promising in the continuing effort to utilize plant species successfully for medicinal purposes in humans, providing further justification for the hypothesis that phenolic compounds in these plants can provide substantial antioxidant activity.

Chemical composition and antimicrobial activity of the essential oils from four Ruta species growing in Algeria.

Antimicrobial properties of plants essential oils have been investigated in order to suggest them as potential tools to overcome the microbial drug resistance and the increasing incidence of food borne diseases problems. The aim of this research is to study the antibacterial and antifungal effects of four traditional plants essential oils, Ruta angustifolia, Ruta chalepensis, Ruta graveolens and Ruta tuberculata, against standard bacterial and fungal strains. The chemical compounds of the oils were examined by GC/MS. Results revealed a powerful antifungal activity against filamentous fungi. Aspergillus fumigatus and Cladosporium herbarum are the most sensitive strains to these oils with MIC values less than 3.5 µg ml(-1) for certain oils, reaching 7.8 µg ml(-1) for other. GC/MS essay exhibited ketones as the most abundant constituent of these oils except for R. tuberculata essential oil which has a completely different composition, monoterpenes alcohols being the most abundant. These compositions explain their potential antifungal activity.