Isolation, Characterization, and Biological Activity of some Fatty Acids and Volatile Oils from Iraqi Eucalyptus microtheca Plant

This study aims at investigating the chemical composition, antimicrobial and antioxidant activity of some extracted essential and fixed oils from leaves of Eucalyptus microtheca plant grown in Iraq. Analysis of the isolated oils has been achieved by gas chromatography coupled with mass spectrometry gas chromatography–mass spectrometry (GC-MS) Technology. The study reveals existence of sixteen compounds. Camphene (20.60%), 4-carene (18.53%), 1,8-cineole (11.96%), terpin-4-ol (8.70%) and p-cymene (8.39%) were the highest components in these essential oils. While nine compounds were obtained as fixed oils, pentadecanoic acid (36.47%) and cis-vaccenic acid (30.31%) were the major components. The antimicrobial activity of the leaves extracts was evaluated against six different gram-positive and Gram-negative bacteria using disk diffusion method and exhibited good inhibition activity. Moreover, antioxidant assay (free radical scavenging activity) demonstrated good activity for the extracted oils. The results show that the aerial parts (leaves) of the Iraqi E. microtheca plant possess antibacterial and antioxidant properties and may suggest it as a good candidate to use for medicinal purposes.

ANTIFUNGAL ACTIVITY OF Eucalyptus microtheca LEAVES EXTRACT AGAINST AFLATOXIGENIC FUNGI

Eucalyptus trees are evergreen, fast growing and widely cultivated in Iraq. Its leaves, buds, capsules and even seeds contain several compounds that have antimicrobilal activity. Fresh leaves were collected and let dry in shade at room temperature then alcoholic and aqueous stock ‎solution (200mg/ml) of leaves extract was prepared in 10% DMSO from which ‎different concentrations were done. Antibiotic susceptibility test was performed by disk diffusion method using FLU, KCA, MCL, ECN and ITC antibiotics. Leaves extracts were also examined for its antifungal activity then the MIC and MFC were determined using microdilution method. KCA, ECN and MCL were the most effective antifungal drugs on most isolates. Only two isolates were resistant to all antibiotics and one isolate showed sensitivity to all antibiotics under study. The methanolic and ethanolic extract of Eucalyptus leaves extract showed the highest inhibitory influence on fungal growth in comparison with the aqueous extract. Furthermore, Alcoholic extracts showed MIC at 50mg/ml and MFC at 100mg/ml. The aqueous extract of Eucalyptus had no inhibitory effect on the growth of all Aspergillus isolates. The results of the present research showed the potential antifungal activity of the Eucalyptus microtheca leaves extract against the aflatoxigenic A. niger and A. flavus, which is an indication of the fungicidal value of the plant extract. This research suggests that the plant extract may possess some compounds with antifungal properties against fungi and it can be used as safe and economic alternative against aflatoxigenic fungal food and feed contamination.

The study of antibacterial activity of some plant extracts against causes of pneumonia

Eighty five samples were taken from patients suffering from pneumonia. Seventy-eight isolates were diagnosed as following: Staphylococcus aureus (23), klebsiella pneumoniae (29), Streptococcus pneumoniae (15), Serratia sp. (4), Haemophilus influenzae (4) and Pseudomonas aeruginosa (3). The clinical isolates were tested for antibiotics sensitivity. They appeared highly resistance to penicillin G and Ampicillin at percentage 89.7 and 84.6% respectly while the results showed highly sensitivity to streptomycin at percentege of (12.8%). To study the antibacterial activity of Alium sativum, Eucalyptus microtheca leaves and Cydonia oblonga seeds extracts, five multi resistant strains were used by using agar well diffusion and disk methods at concentrations of (24, 12, 6, 3)%. The agar well diffusion was prefered for both of Alium sativum and Eucalyptus microthesca extracts while both methods were prefered for Cydonia oblonga extract by measuring inhibition zones .The results showed antibacterial activity of Alium sativum on S.aureus and S. pneumoniae at concentration 3-24 % and for klebsiella pneumoniae at concentration of 6-24%While it was 12-24%for Serratia sp. and Pseudomonas aeruginosa. Eucalyptus microtheca extracts showed antibacterial at concentration of 24-3%for S.aureus, S. pneumoniae and Ps. aeruginosa. While K. pneumoniae and Serratia sp sensitive at concartatins of 24%. The ethanol and oil extracts of Cydonia oblonga seeds had anti bacterial activity at all concentrations for all strains except Serratia sp. showed sensitivity at concentrations of 24-6%for both extracts.