Chemical Composition and Antimicrobial Activity of Flower Essential Oil of Jacaranda acutifolia Juss. against Food-Borne Pathogens

Aims: To investigate the chemical composition and antimicrobial activity of the hydrodistilled flower essential oil of Jacaranda acutifolia Juss. (Bignoniaceae) to validate some of its ethnopharmacologial uses such as treatment of wounds and dermatitis.

Study Design: Volatile oil isolation, component identification and antimicrobial activity.

Place and Duration of Study: Faculty of Pharmacy, Ain Shams University, and the flowers were collected on 15 April 2012 and the study is completed within four months.

Methodology: The essential oil of the flowers of Jacaranda acutifolia was extracted by hydrodistillation, analysed by capillary gas chromatography (GC/FID) and gas chromatography–mass spectrometry (GC/MS). Antimicrobial activity was studied in vitro; this included both antibacterial activity against food-borne pathogens and antifungal activity using agar diffusion method.

Results: Forty six components, comprising almost 81.36 of the total peak area, were identified in the analysis. The main components were n-dodecanoic acid (17.48%), n-tetradecanoic acid (15.59%), n-hexadecanoic acid (10.98%), hexahydrofarnesyl acetone (8.2%), n-decanoic acid (7.9%), and nonacosane (7.71%). According to the observed inhibition zone, which ranged from 13 to 26.5 mm, the oil showed significantly high in-vitro antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans with minimum inhibitory concentration (MIC) values ranging from 0.09 up to 1.09 mg/ml, and moderate antimicrobial activity against Salmonella typhimurium and Shigella flexneri. The potency of the oil was calculated as compared to standard antibiotics, and 1 mg oil was equivalent to 1.05 µg penicillin against S. aureus; 2.72 µg nystatin against C. albicans; 13.55, 1.3 and 272 µg gentamicin against E. coli, Samonella and Shigella species respectively.

Conclusion: The essential oil of Jacaranda acutifolia exhibited promising antimicrobial activity, and this makes its local traditional uses rational.