دراسة كيميائية للزيت الطيار المستخلص من أوراق نبات الريحان Ocimum basilicum وتقييم فعاليته التثبيطية في بعض الأحياء المجهرية المرضية

Abstract

This study include extraction of volatile oil from Ocimum basilicum leaves with steam distillation method using clavenger devise, which was 0.6 %.Volatile oil of the O. basilicum leaves had special aromatic odour, pale yellow color, slightly pungent taste, not dissolved in water, but it dissolved in some organic solvents like ethanol, hexane, ether and chloroform. The specific gravity, refractive index and optical rotation were (0.9243), (1.5155) and (– 1.3) respectively. Regarding the chemical properties, the acid number was (1.68), saponification number was (48.6) and the iodine number was (88.9).The quantities and qualities of the volatile oil were estimated by the high performance liquid chromatography (HPLC) and it was found that it contained 30 volatile compounds, thirteen of them were recognized including α-The inhibition activity of the O. basilicum Volatile oil extracts were studied on some pathogenic microorganisms like Staphylococcus aureus, Salmonella typhi, Escherichia coli, Vibrio cholerae, Aeromonas hydrophila, Serratia marcescens, Klebsiella pneumonia and Candida albicans. Results showed that the volatile oil had an inhibition effect on the growth of all microorganisms, and it gave the higher inhibition effect on the growth of Staph. aureus in which the inhibition zone reached to (21) mm The minimum inhibition concentration (MIC) and the minimum bactericidal concentration (MBC) of the volatile oil extract of the O. basilicum leaves were determined. The highest value of (MIC, MBC) with Staph. aureus was (0.625 , 1.25)%, while the lowest value of (MIC, MBC) with S. marcescens and E. coli were (2.5 and 5) % respectively