In Vitro Effect of Plant Parts Extract of Senecio glaucus L. on Pathogenic Bacteria

Senecio glaucus L. is an annual herb that grows in several Egyptian desert habitats. The diversity of habitats inhabited by this species, as well as its distribution, chemical composition, and biological activity, are all unknown. This research aimed to examine the chemical composition of S. glaucus from various environments in Egypt, as well as the antioxidant and antimicrobial activities. The general assessment of the analytical results for different parts of S. glaucus showed that the capitula and leaves in both inland and coastal samples were rich in bioactive constituents than the other parts as following (capitula > leaf > root > stem). Based on the results of IC50, the antioxidant properties of the eight parts of two samples follows the sequence capitula ˃ root ˃ leaf ˃ stem for the coastal sample, and capitula ˃ leaf ˃ stem ˃ root for the inland sample. The IC50 values ranged from 25.94 to 41.20 mg/ml in coastal sample, where the IC50 values ranged from 28.02 to 42.83 mg/ml in desert sample, compared to ascorbic acid (IC50 = 13.30 mg/ml). The antimicrobial potential of MeOH extracts of S. glaucus parts collected from different habitats exhibited different inhibitory spectrum behavior with varying degrees of inhibition against six Gram-positive bacteria and four Gram-negative bacteria. In both coastal and inland samples, the E. coli inhibition zone was the most susceptible bacterium. Whereas, in the case of the coastal sample, the inhibition zone of B. subtilis was the most sensitive bacterium. The results of the antibacterial test were compared with 3 standard antibiotics.