دراسة التركيب الكيميائي و التضاد البكتيري للزيوت العطرية المستخلصة من قشور ثمار الحمضيات

الملخص EN

Essential oils from peels of 6 citrus species were extracted.

The species were lemon (Citrus limon), orange (C.

sinensis), grapefruit (C.

paradisi), pomelo (C.

maxima), mandarin (C.

reticulata) and bitter lemon (C.

aurantium) using hydro-distillation (Clevenger type).

The chemical composition of the extracted essential oils was identified using Gas Chromatography-Mass Spectrometry (GC-MS).

The total number of identified compounds was 45.

The components and their percentage varied according to the citrus species.

The most common component with the highest percentage was limonene.

Antimicrobial activity of the oil extracts was tested against five Gram-positive bacteria (Staphylococcus aureus, S.

epidermidis, S.

xylosus, S.

lentus and Bacillus subtilis) and nine Gramnegative bacteria (Klebsiella pneumoniae, Enterocobacter cloacae, Citrobacter freundii, Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis, Morganella morganii, Hafnia alvei and Salmonella sp.).

Concentration of oils applied ranged from 4 to 100 µl/ml of Meuller Hinton Broth.

Oil extracted from Citrus limon peel showed the highest antimicrobial activity.

In general Gram-positive bacteria were more sensitive to the oil extracts tested than Gram-negative bacteria, and P.

aeruginosa was the most sensitive within the Gram-negative group.