Effect of sulphur on yield and chemical composition of essential oil of Ocimum basilicum L.

Abstract

This study aimed at assessing the effect of using different sulphur dilutions in the yield and composition of essential oil of Ocimum basilicum L. (basil). Sulphur was applied at different dilution rates with a centesimal scale ranging from 0c (control), 6c, 12c, 24c, to 30c. The experiment was conducted in pots at open atmosphere for 5 months, using a weekly dosage of 250 ml of the different dilution rates. Parameters evaluated were: Yield of essential oil by hydrodistillation (g%) and chemical composition analysis by gas chromatography-mass spectrometry (GC-MS). Results confirmed the effect of sulphur dilutions in the yield and composition of basil essential oil. Both the 6c and the 12c dilution rates led to the highest yield of essential oil (0.15%) when compared to the control (0.08%) and to other dilution rates (P≤0.05). The major chemical components of essential oil changed as the sulphur increased, the concentration of linalol: 33.14%(12c); 30.92%(6c); 27.13%(30c); 23.86%(24c); 7.41%(0c) and eugenol: 33.11%(24c); 32.14%(12c); 28.57%(30c); 26.51%(6c) and 7.8%(0c); in comparison with the control (0c). Economically, the increase of linalol and engenol concentrations are considered important as the essential oil of basil with high concentration of linalool is highly prized in the international market. Key words: Essential oil, Ocimum basilicum, linalool, Eugenol, Sulphur, centesimal scale, dilutions.