Résumé:
This work is concerning the phytochemical study of two Algerian plants, the first belonging to the Fabaceae family (Genista microcephala coss & dur) and Asteraceae family (Jurinea humilis DC). The phytochemical study of the two Algerian medicinal plants allowed the identification of five isoflavonoids from ethyl acetate and butanol extracts of G. microcephala and three flavonoids from butanol extract of J.humilis, isolated for the first time in both plants, The structurs of compounds were elucidated by various spectroscopic methods spectral: 1D and 2D NMR (1H, 13C, DEPT, HMBC and HMQC), UV, mass spectrometry (MS) and by comparison with lettirature valrieus. The biological study carried out to determine the phenolic content and to evaluate the antioxidant and antimicrobial activities of Genista microcephala. Antioxidant activity was evaluated by various in vitro tests, including Ferric Ion Reducing Activity (FRAP), Cupric Ion Reducing Antioxidant Capacity (CUPRAC), and total antioxidant capacities (TAC). The antimicrobial activity of ethyl acetate and butanolic extracts of G. microcephala in addition of fatty acids content of different parts of plant was evaluated against human pathogenic bacteria, fish bacteria and yeast. The used methods were agar diffusion method and the determination of minimal bactericidal and fungicidal concentrations (MBC and MFC). Ethyl acetate extract was the most active regarding antioxidant and antimicrobienne assays. The tested activity seems to be due to the high content of this extract on isoflavonoids.
