Extraction, Characterization and Antibacterial Screening of Oil from the Heartwood of Pterocarpus Erinaceus (African Rosewood Powder)

Kolawole Olorunsola Praise, Ad

Abstract

Oil was extracted from Pterocarpus erinaceus (African rosewood) powder with n-hexane using a soxhlet apparatus. The percentage yield of the oil was 5.1%. The oil had saponification value of 144 mg KOH/g; iodine value of 3.03 g I2/100 g; acid value of 3.78 mg KOH/g; peroxide value of 3.4 m Eq/Kg; refractive index of 1.473 and specific gravity of 0.7424. Thin-layer chromatography of the oil with hexane/chloroform (3:1) revealed three different components with retention factors of 0.4328, 0.2388 and 0.1493. The components of the oil were determined using Gas Chromatography-Mass Spectrometry. The fatty acids detected include palmitic acid, linoleic acid and stearic acid. Some saturated hydrocarbons were also identified. The antibacterial activity of the oil was tested on Staphylococcus aureus, Escherichia coli, Bacillus cereus, Salmonella dysenteriea, Enterococcus faecalis, Pseudomonas aeruginosa, Klebsiella spp and Salmonella typhae using Agar-diffusion method. The results of the physicochemical parameters and antimicrobial activity study show that the oil obtained from Pterocarpus erinaceus powder is non-drying oil containing saturated hydrocarbons and fatty acids. It can find application in the soap and cosmetic industries. It can also be used as hydraulic brake fluid and as lubricant, but it cannot be used as antibacterial agent.