Abstract: | This work describes an effective combined ultrafiltration (UF)-nanofiltration (NF) membrane process for the separation and concentration of pediocin PA-1 from fermentation broth. Three polysulfone (PS) membranes with MWCOs of 5, 10, and 30 kDa were tested for ultrafiltration effectiveness. The 10 kDa membrane was selected because it displayed high permeability, good pediocin PA-1 recovery and reduced fouling. When the volume concentration factor (VCF) of UF reached 2.5, continuous diafiltration (DF) was carried out. The optimal diafiltration factor (DFF) was 1. The permeate obtained from UF was then concentrated by NF. When the VCF of NF reached 4.5, pediocin PA-1 recovery loss was only 10.5%. This two-stage membrane process improved the loading solutions by 4.5-fold, allowing up to 71.6% recovery of pediocin PA-1. After the membrane process, the NF retentate could be concentrated and subjected to preparative chromatography to obtain purified pediocin PA-1, or it could be dried to obtain a rich pediocin PA-1 preservative. |