Characteristics of low molecular weight heparin production by an ultrafiltration membrane bioreactor using maltose binding protein fused heparinase I

Low molecular weight heparin (LMWH) produced by the degradation of heparin has been widely used for clinical use, because it retains heparin's anticoagulant activity while has fewer side effects. In this study, a bioprocess for efficient production of LMWH was established by an ultrafiltration (UF) membrane bioreactor using maltose-binding protein (MBP)-heparinase I. The absorption of the reaction mixture at 235 nm (A235) was used as an indicator for monitoring the enzymatic reaction and product quality. When A235 of the reaction mixture reached 45, the produced LMWH reached a weight-average molecular weight (Mw) of approximately 5038 Da, a number-average molecular weight (Mn) of 3498 Da, the anti-factor Xa activity of 154.95 ± 5.80 IU/mg, and the ratio of anti-factor Xa activity to anti-factor IIa activity of 2.2, which all meet the standard of European Pharmacopoeia 5.0. The average molecular weight of LMWH showed a good linear relationship with the increment in A235. These results indicated that the qualified LMWH could be produced by the UF membrane bioreactor using the fusion enzyme.