Comparative chemical constituents and antimicrobial activity.

Abstract

Preservative and antimicrobial role of essential oils extracted from spices and the role of their various components in terms of prevention of food spoilage had been studied. A comparison of the antimicrobial activity of essential oils to that of different antibiotics had also been carried out which might yield significant information as to whether extracts can be employed as replacement of preservatives. Different levels of antimicrobial activity depend on chemical components and their relative amount1. Turmeric treated under different conditions (fresh, sun-dried, and oven-dried) were extracted by water distillation and by using a Soxhlet apparatus for 24, 48, and 72 hours to obtain various solvent extracts. The chemical constituents of turmeric oils (Curcuma longa L.) and four commercial essential oils: anise (Pimpinella verum), clove (Eugenia caryophyllata), orange (Citrus sinensis), and peppermint (Mentha x piperita L.), were then analyzed by gas chromatography and mass spectrophotometer to identify their major constituents. All essential oils were evaluated for their antimicrobial activities on six pathogenic bacteria, two fungi, and one yeast: Bacillus cereus ATCC 11778 DMST 5040 (Lot. 1320), Escherichia coli ATCC 25922 DMST 4212 (Lot. 1343), Pseudomonas aerugenosa ATCC 27853 DMST 4737 (Lot. 1342), Staphylococcus aureus ATCC 25923 DMST 8840 (Lot. 1302), Salmonella typhi, Vibrio parahaemolyticus ATCC 17802 DMST 21243 (Lot. 1312), Aspergillus niger ATCC 16404 DMST 15538, Aspergillus flavus, and Candida albican. Two different methods were employed for the determination of antimicrobial activities: disc diffusion method for screening and broth dilution for minimum inhibitory concentrations (MICs) of the essential oils2.