Optimization of SWIETENIA MAHAGONI seed in supercritical carbon dioxide extraction

Abstract

Supercritical carbon dioxide extraction has been used for extraction of essential oil from Swietenia mahagoni seed. The effect of different particle sizes on diffusivity coefficients, D (m2/s) were studied by applying second Fick’s law of diffusion proposed by Crank. Particle size of 710 µm showed the highest D of 3.1 x 10-12 m2/s. Gas compression at pressure of 30 MPa and temperature of 60 oC on seeds caused swelling thus allowed faster diffusion of carbon dioxide through porous structure of Swietenia mahagoni seed. For optimization of Swietenia mahagoni seed oil extraction, a three-level factorial design in response surface methodology was used to analysis the effect of pressure (20 – 30 MPa) and temperature (40 - 60 oC) on extraction oil yield. The highest extraction oil yield of 29.70% was obtained at pressure of 30 MPa and temperature of 40 oC. This explained that increased pressure and low temperature increased the carbon dioxide density. Thus, higher solute bonding in solvent phase and consequently higher the extraction yield was obtained. Qualitative phytochemical analysis showed the presense of alkaloid, saponin, triterpenoid, phenolic hydroquinone and tannin but absense of flavonoid. Toxicity test of Swietenia mahagoni seed extract using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on human skin fibroblast cell (HSF 1184) showed cell viability above 80%. The result showed that Swietenia mahagoni seed extracts at studied concentrations (10, 1, 0.1, 0.01, 0.001, 0.0001 mg/ml) are non toxic.