Antimicrobial and antioxidant activities of some plant extracts

Abstract EN

In this study, three plants; rosemary, ginger, and peppermint, were extracted using three solvents; ethanol, methanol and water.

A comparison was held between different extracts concerning: chemical composition, efficiency of the extraction method, yield, antimicrobial and antioxidant potentials.

Phenolic compounds profile were studied via High Performance Liquid Chromatography (HPLC).Antimicrobial activity of the extracts was examined against: Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus pyogenes, Candida albicans, Klebseilla pneumonia, Bacillus subtilis and Streptococcus.

spp using agar well diffusion method.

The inhibition zones diameter (IZD) were ranged between 11- 37 mm.

The results showed that ethanol extraction had the highest yield of rosemary and peppermint (19.17 and 17.19%, respectively).

While; the lowest was obtained from ginger methanol extracts (12.78%).

Rosemary water extract had the highest total phenolic contents (271.66 ± 12.2 µg/mg, while ethanol extract of ginger and peppermint gave 201.31 ± 8.99 and 165 ± 4.74 mg gallic acid equivalent (GAE/g) respectively.

Concerning the total flavonoid contents; rosemary methanol extract gained the highest content (123.9 ± 2.99 µg/mg), while in ethanol extracts of ginger and peppermint showed the best results (44.06 ± 0.55, 89.54 ± 2.63 µg/mg, respectively).

Antioxidant activity was used as a parameter to evaluate the protective antioxidant ability of examined herbs represented in IC50 (inhibition concentration).

Results showed that in rosemary water extract 24.5µg/ml, while in ginger and peppermint ethanol extracts was 38.98 and 80 µg/ml, respectively.

Depending on results stated above, it can be recommend using water for rosemary extraction and ethanol 70% for ginger and peppermint extractions for the best antioxidant and antimicrobial impact.