ANTIMICROBIAL AND ANTIOXIDANT ACTIVITIES OF SOME PLANT EXTRACTS

El-Naggar, Mahdy N.; Abdulla, G.; El-Shourbagy, Gehan A.; El-Badawi, A. A.; El Sohaimy, S. A.

doi:10.21608/zjar.2017.52305

ANTIMICROBIAL AND ANTIOXIDANT ACTIVITIES OF SOME PLANT EXTRACTS

Document Type : Original Article

Authors

¹ Food Technol. Dept., Arid Land Cultivation Res. Inst., City of Sci. Res. and Technol. Applications, Univ. and Res. Cent. District, New Borg El Arab, 21934 Alex., Egypt

² Food Sci. Dept., Fac. Agric., Zagazig Univ., Egypt

10.21608/zjar.2017.52305

Abstract

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. sppusing 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.

Keywords