1,2-Propanediol-betaine as green solvent for extracting α-mangostin from the rind of mangosteen fruit: Solvent recovery and physical characteristics

Deep Eutectic Solvents (DESs) are emerging as alternative green solvents. Unlike ionic liquids, DESs are more environmentally friendly and non-toxic, so that they are more suitable to be used in pharmaceutical and food production processes. Few studies reported that DESs, which are liquid at room temperature, can be applied for extracting bioactive compounds from plants. In this study, DESs were formed by mixing betaine as the hydrogen bond acceptor with 1,2-propaneddiol as as the hydrogen bond donors. The aims of the study were to evaluate the extraction condition of mangostins from the mangosteen (Garcinia mangostana L.) rind using 1,2-propanediol-betaine DES and the recovery of solvent by separating the mangostin from DES after extraction. The extractions were conducted in a temperature range of 27-75 °C and the extracts were analyzed using high performance liquid chromatography. The highest a-mangostin extraction yield of 4.14 % (g/g) was obtained using 1,2-propanediol betaine DES at 55 °C. Back extraction of mangostins from DES using ethyl acetate can regain mangostins as much as 88.4% (g/g). The results showed the potential of 1,2-propanediol betaine DES as solvent for extraction of mangostin at mild condition with easy solvent recovery.