Extraction of carotenoids from <Emphasis Type="Italic">Lycium ferocissimum</Emphasis> fruits for cotton dyeing: Optimization survey based on a central composite design method

Studies were carried out to assess the extraction yield of carotenoids from the African boxthorn (Lycium ferocissimum Miers, Solanaceae) fruits with different solvents and solvent mixtures, to optimize the extraction conditions for maximum recovery and to improve the extraction efficiency. Among other solvents, a mixture of hexane and acetone gave the highest carotenoid extraction. Extraction conditions, such as hexane percentage in hexane/acetone solvent mixture, solvent-solid ratio, and extraction time were optimized using a statistically designed experiment. A regression equation for predicting the carotenoid yield as a function of three extraction variables was derived by statistical analysis. The optimized conditions for maximum carotenoids yield were 45 % hexane in solvent mixture, solvent-solid ratio of 70 (ml/g) and extraction time 70 min. The dyeability of cotton with carotenoids extract has also been studied. Unmordant and postmordanted bleached cotton fabric with alum and ferrous sulphatewas dyed. Color measurements and fastness properties as light, rubbing and wash were tested.