Phytochemical profile, antioxidant and antimicrobial activities of Traganum nudatum Delile aerial parts organic extracts collected from Algerian Sahara’s flora

The aim of this study was to investigate for the first time the antioxidant and the antimicrobial activities of organic extracts from Traganum nudatum Delile using in vitro models. The extracts which exhibited the highest activities were then submitted to RP-HPLC–PDA analysis. The phytochemical screening revealed the presence of flavonoids, tannins, alkaloids, saponins and quinones. The highest amounts of polyphenols, flavonoids and flavonols were recorded in ethyl acetate fractions. The strongest DPPH scavenging ability was attributed to ethyl acetate fraction of crude extract prepared by maceration EAFM with IC50 value of 20 ± 0.11 µg/mL, ethyl acetate fraction of crude extract prepared by infusion EAFI was found to possess the highest ferric reducing power with EC50 of 35 ± 0.4 µg/mL. The highest antioxidant capacity 200.21 ± 0.2 mg AAE/g was exhibited by n-butanol fraction of crude extract prepared by maceration BFM. The antimicrobial activity was proven against all the tested microorganisms except on Candida albicans strains. The extracts were more active on Gram positive than Gram negative bacteria. The strongest inhibition was provided against Bacillus subtilis, Bacillus cereus and Listeria monocytogenes. The identification of phenolic compounds using RP-HPLC–PDA technique revealed the presence of sinapic, syringic, ferulic, p-coumaric acids, catechin, naringenin and vanillin that may be responsible for the bioactivities of the reported specie. Our results indicate that T. nudatum Delile may provide a rich and novel source of natural antioxidants for industrial utilization replacing synthetic ones.