Influence of Extraction Methods on Thermal Properties and Antimicrobial Activity of Moringa peregrina Seeds Oil

The aim of the present study was to investigate the effect of extraction methods on the thermal properties and the antimicrobial activity of Moringa peregrina seeds oil. The oil was extracted by cold pressing (CP) and maceration in n hexane (MH). The yields of the oils were 9.12% % and 21.87% respectively. Except the peroxide value, the chemical properties of the oil extracted by the two methods remained fairly unchanged. Additionally, the results have revealed that the oil which was extracted by cold pressing has higher activity against all tested organisms (Bacillus subtilis, Staphylococcus aureus Escherichia coli, Pseudomonas aeruginosa, Candida albicans) in comparison to the one obtained by maceration method. Furthermore, the thermogravimetric analysis has demonstrated significant variations in the onset of degradation between the oil samples extracted with the two methods; 200◦C (cold pressing) against 274◦C (maceration). The maximum mass loss for the oil extracted by the two methods does not differ significantly whereas the final degradation temperature almost similar. Finally, the differential scanning calorimeter thermograms for the oil extracted by the two methods showed somewhat similar characteristics regarding the melting temperatures and melting enthalpies as well as crystallization temperatures and crystallization enthalpies.