Harvesting of microalgae by flocculation with poly (γ-glutamic acid)

► Poly (γ-glutamic acid) is tested for harvesting oleaginous microalgae. ► Application the optimized flocculation methods to microalgae gives higher than 90% flocculation efficiency. ► Poly (γ-glutamic acid) causes no damage to cell integrity during flocculation. ► Poly (γ-glutamic acid) is proved to be feasible for harvesting microalgae.