Antibacterial activity of Pulicaria odora leaf phenolics collected in Algeria

Background: Pulicaria is a genus of the Asteraceae family, tribe Inuleae, containing 100 species with a distribution from Europe to North Africa to Asia. Objective: In this work, the study is focused on the difference in phytochemical and antibacterial activity of Pulicaria odora harvested in two regions of northern Algeria. Methods: Two maceration extraction methods were used; at room temperature and bath shaker at 37 °C. Total phenolics and flavonoids were carried out using folin ciocalteu and aluminium chloride methods, respectively. Antibacterial activity was evaluated by agar diffusion method on four bacterial strains Listeria innocua, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa. Results: The results found showed that the highest total polyphenol content was 271,8 ± 22,52 mg gallic acid equivalent / g dry matter (mg GAE/g of DM); the best flavonoid content is 51,53 ± 4,42 mg quercetin equivalent / g of dry matter (mg QE/g of DM) harvested in Bejaia. The best level of total polyphenols and flavonoids from the plant harvested in the region of Tizi-Ouzou are 218,23 ± 12.33 mg GAE / g of DM, 54,15 ± 5,98 mg QE / g DM respectively. The two phenolic extracts obtained by the two solvents at a concentration of 70% are more active against S. aureus (17.66 mm for the sample of Bejaia at the concentration 1mg /20µL), while a moderate sensitivity is recorded against other strains for the two samples. Conclusion: Pulicaria odora leaf extract is strong against bacterial infection and can be used as medicinal remedy and in food industry.