Lipase-mediated hydrolysis of hempseed oil in a packed-bed reactor and in-line purification of PUFA as mono- and diacylglycerols

Mono- and diacylglycerols (MAG and DAG, respectively) of polyunsaturated fatty acids (PUFA) are raising an increasing interest as novel non-ionic food emulsifiers owing to the recognized health-promoting effects of PUFA. We here reported on the lipase-catalyzed hydrolysis of hempseed oil in a homogeneous medium based on oil and t-BuOH/water carried out in a continuous flow packed-bed reactor (PBR). The biotransformation was carried out by feeding the reaction mixture upwards the PBR at varying flow rates through a peristaltic pump. The system was coupled in-line with a second glass column filled with an ion-exchange resin to retain hydrolyzed free fatty acids (FFA), thus allowing the straightforward purification of the glyceride component. A mixture of MAG and DAG (yield 40%, 620 mg) composed of linoleic and α-linolenic acid (82%) and oleic acid (16%) was obtained in less than 2 h. The lipase-based PBR was used for 10 cycles without any loss of activity.