Characterization and Biological Activities of Oils from Seeds of Khaya senegalensis , Eruca sativa and Pisum sativum used in Sudanese Traditional Medicine

Abstract

The Khaya senegalensis , Eruca sativa, Pisum sativum are key species in Sudanese system of medicine. The seed oils of these species were extracted to determine physical properties of oils and evaluate for antimicrobial and antioxidant activity and analyzed by GC-MS. GC-MS analysis of Khaya senegalensis oil showed the presence of 23 constituents dominated by 9-octadecenoic acid (Z) – methyl ester (47.43%). The oil from Eruca sativa showed 30 constituents and major component is 13-Docoenoic acid, methyl ester (31.92%). Pisum sativum oil revealed the presence of 33 constituents dominated by 9, 12-octadecadienoic acid (Z, Z)-, methyl ester (30.69%). Furthermore, these oils were assessed for their antimicrobial activity against pathogenic bacteria: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus Subtilis and fungal species Candida albicans. In the cup plate agar diffusion bioassay Khaya senegalensis oil showed significant activity against Staphylococcus aureus (15 mm) but it was inactive against other test microorganisms. Eruca sativa showed highly significant activity against Escherichia coli (20 mm) and Staphylococcus aureus (20 mm) but it was inactive against other test microorganisms. while Pisum sativum showed highly significant activity against all tested organisms (Pseudomonas aeruginosa 20 mm, Staphylococcus aureus 24 mm, Bacillus Subtilis 20 mm, Candida albicans 20 mm) and significant activity against Escherichia coli (14 mm). In the DPPH radical scavenging assay, Khaya senegalensis, Eruca sativa, and Pisum sativum oil showed significant antioxidant activity (90, 37, and 82%)