Malagasy aromatic plants: Essential oils, antioxidant and antimicrobial activities

This work examined the chemical profile of nine volatile oils from Madagascar and evaluated their antimicrobial and antioxidant activity. Essential oils with the highest levels of eugenol exhibited the highest antioxidant activity. Clove bud (Syzygium aromaticum) oil appeared the most promising for potential applications as a food preservative because showed the highest antioxidant and antimicrobial against bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa) and fungi (Aspergillus niger, Saccharomyces cerevisiae). Cinnamon leaf (Cinnamomum zeylanicum) oils with a very high antioxidant activities were also effective though less than the clove bud oil against the growth of the microorganisms tested. Cinnamon bark (C. zeylanicum) oil exhibited a low antioxidant activity yet had a high antimicrobial activity against the five tested microorganisms. Linalool basil oil (Ocimum basilicum) showed an intermediate antioxidant activity and was most active against A. niger and E. coli. P nigrum essential oil was most active against fungi (A. niger, S. cerevisiae), while Tagetes minuta was most active against S. aureus. The bark essential oil of Ravensara aromatica showed low antioxidant and antimicrobial activity.