An optimized strategy for lutein production via microwave-assisted microalgae wet biomass extraction process

Lutein is a bioactive substance with functional properties, applicable in food supplementation and food fortification. Wet microalgae biomass processing is a propitious practice, yet receives limited exploration for lutein production. Here, novel microwave-assisted extraction methods utilizing wet biomass are designed. By manipulating the chemical composition and mixing process of the extraction mixture, mass transfer was improved thus maximising lutein liberation from biomass. Through our optimum extraction method, the amount of lutein recovered increases by 1.88 fold (from 8.06 mg/g to 15.14 mg/g), uses - 125.32 fold less amount of KOH solution (from 142.86 ml to 1.14 ml), uses - 8.34 fold less amount of acetone (from 1428.57 ml to 171.3 ml), requires - 1.80 fold less extraction time (from 36 min to 20 min) and consumes - 30.85 fold less energy (from 106.73 kWh to 3.46 kWh) as compared to the dried biomass extraction. Extracted lutein also retained high antioxidant capacity in 0.43 +/- 0.16 mu mol alpha-tocopherol equivalent. This designed process is feasible as wet biomass could be stored in a refrigerator up to 3 weeks without affecting the amount of extractable lutein. The outcome of this proposed lutein production method has achieved high product recovery, quality, remarkable process efficacy and potential sustainability for future industry application.