Optimization of inulin extraction from sisal wastes using Response Surface Methodology

Abstract

Inulin, a natural prebiotic dietary fiber with several health benefits, is commonly extracted from Jerusalem and Chicory plants. Even though boles and sisal wastes contain a high amount of inulin, extraction of inulin from such materials has not been well explored or optimized. The conventional methods that are normally used in inulin extraction from other plant sources have created a foundation for the extraction of inulin from sisal wastes. However, the methods need to be optimized to improve yield and quality. The purpose of this study was to identify and optimize important factors that influence inulin extraction. The Response Surface Methodology (RSM) with Box–Behnken design involving three levels of three independent variables (i.e. extraction temperature, extraction time, and solvent composition) was used. A second-order polynomial equation was formulated to describe the relationship between the dependent and independent variables. The optimal extraction conditions, which had high a inulin yield (18.24%), were extraction temperature of 80°C, time of 90 min, and solvent composition of 40%. The analysis of variance (ANOVA) indicated that the model was highly significant, with a coefficient of determination (R²) of 0.9205. The optimization of the extraction process of inulin from sisal waste resulted in a significant increase in the yield of the extracted inulin. Therefore, sisal waste can be a potential source of inulin, and the optimized extraction process can be useful in industrial applications.