Strategy for high-yield astaxanthin recovery directly from wet Haematococcus pluvialis without pretreatment

A novel integrated extraction technique for high recovery of natural astaxanthin from wet encysted Haematococcus pluvialis (H. pluvialis) is demonstrated. The technique can be used to effectively disrupt the cell wall and perform extraction in a one-pot system without a high-energy, cost intensive pre-drying step. The most suitable green solvent was researched in terms of high extraction yield and astaxanthin recovery. Moreover, an optimized condition for the selected green solvents was determined by varying process parameters, viz., the ball milling speed (100-300 rpm) and time (5-30 min). A high recovery of astaxanthin directly from wet H. pluvialis (30.6 mg/g based on its dry mass) and a high extraction yield (58.2 wt%) were achieved using ethyl acetate at 200 rpm after 30 min. Therefore, compared to its counterparts, the biphasic solvent system plays a key role in achieving high extraction yield and astaxanthin recovery from wet H. pluvialis.