Isocyanate-mediated immobilization of Candida antarctica lipase B onto resin for efficient 1,3-diacylglycerol bio-synthesis

In this work, isocyanate-based strategy was developed for efficient immobilization of Candida antarctica lipase B (CALB). Of 41 commercial resins, EP109 was chosen and hydrophobized with hydroxyl-terminated polydimethylsiloxane (HTPDMS) for tert-butyl isocyanate (tBIC)-based CALB immobilization due to high loading amount and specific activity. The tBIC-based strategy exhibited shorter immobilization time, higher loading and activity than adsorption strategy by hydrophobic interaction. When compared with free CALB, EP109-HTPDMS-tBIC@CALB owned improved stability (against acid, alkali, and heat) and storability. Subsequently, EP109-HTPDMS-tBIC@CALB was employed in the bio-synthesis of 1,3-diacylglycerol in a solvent-free system with a yield of 76.31%, which was higher than commercial Novozym 435 (53.93%). EP109-HTPDMS-tBIC@CALB exhibited 76.34% of residual activity after 20 repeat uses.