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Micromeria inodora (Desf.) Benth. is most studied for the antimicrobial activity of their essential oils; nevertheless there are no reports on the phenolic compounds of this species and their antioxidant activity. In this study, aqueous and organic extracts were assayed for their antioxidant activity. The polyphenol and total flavonoid content, varied between 175.50 to 332.62 mg GAE/g extract and 65.38 to 86.30 mg catechin equivalent/g extract, respectively.The results of antioxidant activity have shown that all extracts reported an important activity and the ethyl acetate extract showed the stronger effect, higher than some standards molecules. Its IC 50 value of scavenging DPPH is 1.5 ± 0.001μg/mL; β-Carotene Bleaching assay (BCB) IC 50 = 28.1± 0.001μg/mL and the Ferric Reducing Antioxidant Power (FRAP) IC 50 = 6.96 0.05 μg/mL. RP-HPLCPDA analysis of phenolic compounds revealed the presence of phenolic acids and flavonoids as: gallic acid, quercetin, rutin, vanillin and naringenin.

In this research, the antimicrobial function of the aqueous and organic essences obtained from Ziziphus jujuba pulp fruits was investigated against strains of bacteria and fungi. The RP-HPLC-PDA analysis was observed in the hydro-acetone (EA) and ethyl acetate extracts (Acet1, Acet2) in the presence of gallic acid, quercetin, and rutin. Most extracts present a slight antimicrobial activity with an inhibition zone not exceeding 6.5 mm diameter, except for S. aureus which was the most sensitive strain. The Minimum Inhibitory Concentration (MIC) values ranged between 450 and 110 mg/mL, E. coli and S. aureus are the most sensitive strains for all extracts. No particular antifungal activity of extracts was observed against C. albicans strain. The antimicrobial activity of Z. jujuba pulp fruits has not been reported before, and the present study has revealed that the phenolic compounds identified in jujube fruit extracts cannot provide an important antimicrobial effect to jujube pulp fruits.

The aim of this study is to evaluate the antioxidant activity of dried fruit extracts of Zizyphus jujubaMill. Polyphenols and flavonoids content determined in aqueous extract (aq), hydromethanolic (EM), hydroacetonic (EA) extracts, and their ethyl acetate (Acet) andn-butanol (n-but) fractions reveal variable rates; 42.84–94.70 mg gallic acid equivalent per g extract and 47.02–427.33 mg catechin equivalent per g extract. The antioxidant activity was evaluated by different assays using total antioxidant capacity, 2,2-Diphenyl-1-picrylhydrazyl (DPPH), β-carotene bleaching assay, and ferric reducing antioxidant power (FRAP). In DPPH assay, all extracts showed an interesting scavenging effect, an estimated reduction rate about 75.58–97.71% was determined with the IC50(the half maximal inhibitory concentration) values ranging from 12 to 503.6 μg/ml. In β-carotene bleaching assay, 500 μg/ml of each extract showed a large inhibition (51.14–85.01%) with IC50values ranging from 48 to 462 μg/ml compared to butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and tannic acid 0.6, 2.00, and 461 μg/ml, respectively. The results of FRAP show that the crude extracts (aq ˃ EM ˃ EA) are less efficient than their fractions (Acet/aq˃ Acet/EA˃n-but/EA) which demonstrate an important activity. Concerning total antioxidant capacity essay (TAC), the highest capacity was noticed for Acet/aq (71.98 μg gallic acid equivalents [GAE]/mg extract) and Acet/EA extract (64.62 μg GAE/mg of extract). The antioxidant activity of dried fruit extracts ofZ. jujubais mainly related to its polyphenol content essentially on flavonoids, which qualifies this species as a source of natural antioxidant.