Antioxidative and antimicrobial activity of ancient Egyptian medicinal plants

Egyptian medicinal plants are being used as pharmaceutical ingredients, and in other innovative ways as in food or feed supplementation [1, 2, 3]. Therefore, the present study was carried out to screen the bioactive compounds in selected Egyptian medicinal plants and to evaluate the antioxidant and antimicrobial activities of plant extracts in model system and in Egyptian food.

Phenolic compounds of methanol extracts were separated and identified using HPLC. The antioxidant activity of plant extracts was tested in β-carotene-methyl linoleate system and also evaluated in sunflower oil at ambient temperature and during frying of potato chips. The antimicrobial activities of extracts were determined by disc diffusion with Gram-positive and Gram-negative species and also evaluated in salted fish [4].

The results showed that rosemary, sage, thyme and garlic extracts (600 ppm each) were the most active natural antioxidants in model system and in sunflower oil during storage in the dark at ambient temperature [3]. Combination of these four extracts (100 ppm each) showed the strongest antioxidant activity in sunflower oil during frying. Garlic, thyme and ginger extracts (1200 ppm, 30mg extract/disc) were found to be active against all tested microorganisms. Combination of extracts (300 ppm each) prevents the growth of Staphylococcus aureus in salted sardine.

It could be concluded that the combination of tested plants showed promising antioxidant and antimicrobial activities, thus justifying their traditional and innovative uses.

References: [1] Abdalla, A.(1999) Adv. Food Sci.(CMTL) 21: 100. [2] Abdalla, A., Roozen, J.(2001) Eur. Food Res. Technol., 212: 551. [3] Abdalla, A. (2004). ^3rd Euro Lipid Congress, Edinburgh Univ., Scotland (5–8 Sept.). [4] Abdalla, A., Daud, S. (1994) J. Agric. Res. Tanta Univ. 20: 252