Optimization of lutein extraction from scenedesmus almeriensis using pressurized liquid extraction

Lutein is a powerful carotenoid that is used as a feed additive for the colouring properties and as supplement in nutraceutical products. Its principal healthy properties are antioxidant, anti-inflammatory and protective against age-related macular degeneration. Lutein is indeed a macular pigment in human eyes between zeaxanthin and their function is very important for the eyes health. Lutein is found in some vegetables as spinach, parsley, and kale with a content of around 1-10 mg/100 g. The commercial and recognized source of lutein is the plant marigold (Tagetes erecta L.). Lutein is extracted from marigold petals as oleoresin and the lutein content can be around 0.03% (based on dry biomass weight). Since the costs for harvesting are expensive, land and water use are requested for marigold cultivation and due to the seasonality of the growth, an alternative source of lutein has been searched among microalgae. Scenedesmus almeriensis is considered a promising source for lutein production whose content is around 4.5 mg/g dry weight. The aim of this paper is to improve lutein extraction from Scenedesmus almeriensis by using pressurized liquid extraction through accelerated solvent extractor (ASE 200©Dionex). Extractions were performed using different solvent as the mixture chloroform:methanol (1:1 v/v), ethanol, hexane, acetone. Several temperatures were tested from 20° to 80°C and biomass was mechanically pre-treated. Each extraction cycle was repeated until to complete biomass decolouring.