OPTIMIZATION OF EXTRACTION CONDITIONS OF NATURAL DYE FROM EUCLEA DIVINORIUM USING RESPONSE SURFACE METHODOLOGY

Abstract

Dyes acquired from diverse natural sources are biodegradable and require minimal use of chemicals during extraction which makes them appropriate alternatives to synthetic dyes which are non-biodegradable and toxic to the environment. In this research optimization of extraction conditions of natural dye extract from Euclea divinorium was conducted using Response Surface Methodology (RSM). M:L (material to liquor ratio), temperature and time were optimised using methanol and water as the extraction solvents. The combined effects of the investigated extraction conditions on absorbance at maximum wavelength of 339nm 341nm for aqueous and methanolic extractions, respectively, were studied using Central Composite Design (CCD) of experiment. Analysis of variance (ANOVA) was used to evaluate the efficiency of the statistical model fitted to the experimental design. The optimum values for aqueous dye extraction were found to be 7.5g:100mL, 84C and 146 minutes while the optimum values for methanolic dye extraction were found to be 7.5g:100mL, 60C and 129 minutes with absorbance values of 1.051 and 1.092, respectively. The theoretical and the experimental optimum absorbance verified experimentally were in agreement hence the statistical model was found to be valid.

Keywords

• natural dye
• e. divinorium
• optimization
• response surface