An Environmentally Friendly and Efficient Method for Extraction of PHB Biopolymer with Non-Halogenated Solvents

The present study developed an efficient and environmentally friendly method for recovering polyhydroxybutyrate (PHB) from Cupriavidus necator. Several non-halogenated solvents were tested and it was found that butyl acetate and ethyl acetate are powerful solvents for the biopolymer. Testing was performed to examine the effects of temperature (25 °C until temperature below solvent boiling points) and heating incubation time (0-60 min) on the two solvents. Butyl acetate had a higher recovery level (96%) and product purity (up to 99%) than ethyl acetate at 103 °C and a heating incubation time of 30 min. Under these conditions, PHB recorded the highest molecular weight of 1.4 × 10(6) compared with the standard procedure (i.e., recovery using chloroform). The proposed strategy showed that butyl acetate is a good alternative to halogenated solvents such as chloroform for recovery of PHB.