Paper Title
Prediction of Oil Yield from Loofah Seeds (Luffa cylindrica L.) Using Response Surface Method

Abstract
In Nigeria, Luffa cylindrica plant grows in the wild, uncompleted buildings and fenced walls in villages and towns. The seed which contains about 30 % oil content is often discarded as waste and literature is sparse on optimum oil extraction of the seed. The oil extracted from Luffa can be used for biodiesel production which is now gaining wide acceptance because of low CO2 emission and other considerations. This research work focuses on oil extraction from loofah seed using a solvent extraction method. Optimum conditions for oil extraction were determined using Response Surface Methodology of Central Composite Rotatable Design. A total of 20 experimental runs were used to investigate the optimum condition considering three independent variables at five levels each: extraction temperature (55, 60, 65, 60, 75ºC), seed/ solvent ratio (0.04, 0.05, 0.06, 0.07, 0.08 g/ml) and extraction time (4, 5, 6, 7, 8 hr.). An empirical model equation was developed to predict oil yield as a function of the independent variables, and the optimum oil yield obtained was 27.43% at the corresponding extraction temperature (74.05ºC), seed/solvent ratio (0.05 g/ml) and extraction time (5.35hr). The Analysis of Variance results showed that the coefficients of determination were significant (p = 0.05). The R2 and R2 adj. value of 0.9656 and 0.9346 respectively indicated good fitness. The result showed that the selected independent variables had a significant effect on the oil yield, thus an optimum condition was established. Keywords - Loofah seed, Solvent extraction, Oil yield, Optimization, Model equation.