Antioxidant and antibacterial properties of anise (Pimpinella anisum L.)

Background There is a great interest in the discovery of novel natural bioactive compounds in today's world. Plants, in particular, from different ecological niches and taxonomic groups are known to produce a high number of naturally occurring secondary metabolites, many of them with unique pharmacological activities. Therefore, the primary aim of the study was to investigate the antioxidant and antimicrobial activities of anise. Materials and methods The antioxidant and antimicrobial properties of different solvent extracts (ethanol and water) prepared from two parts (seeds and aerial parts) of Pimpinella anisum were evaluated. The antioxidant capacity was studied through the evaluation of the free radical-scavenging effect on the 1,1-diphenyl-2-picrylhydrazyl radical. The antimicrobial activity was analyzed using the well diffusion method, where zones of inhibition were used as indicators of antimicrobial activity. Results and conclusion The highest percentage of radical-scavenging activity (91.31.8%) was recorded for the ethanolic extract of seeds at a concentration of 0.3mg/ml, followed by the aqueous extract of seeds (82.01.2%), whereas the aqueous extract of aerial parts demonstrated the lowest frequency of radical-scavenging activity (39.01.7%) at the same tested concentration. The largest inhibition zones were determined to be 21.01.2, 18.31.5, 9.71.2, and 7.01.2mm for Bacillus cereus, Staphylococcus aureus, Salmonella typhimurium, and Escherichia coli, respectively. On the whole, the results demonstrated the superiority of seed extracts over aerial part extracts. The results also indicated the stronger activity of ethanolic extracts compared with aqueous extracts. These results offer insights into the antioxidant and the antimicrobial potency of this Egyptian local plant and provide a basis for further phytochemical and pharmacological research.