A combined bioprocess of biodiesel production by lipase with microbial production of 1,3-propanediol by Klebsiella pneumoniae

A novel integrated bioprocess combining biodiesel production by lipase with microbial production of 1,3-propanediol (1,3-PD) by Klebsiella pneumoniae using a hollow fiber membrane was investigated. Glycerol, a byproduct produced during the transesterification, can pass through the membrane and is converted to 1,3-PD directly by K. pneumoniae. The highest conversion of biodiesel obtained after 20 h was 84%, and the molar yield and productivity of 1,3-PD were 0.47 mol mol−1 and 1.7 g l−1 h−1, respectively. Although partial methanol (11% of the total methanol) penetrated into fermentation broth with glycerol, its effects on cell growth and products formation were not significant. The combined bioprocess avoids glycerol inhibition on lipase, reduces the production cost and raises productivity for biodiesel and 1,3-PD.