Abstract

A water activity control system for enzymatic synthesis in organic media, for litre-scale reactors has been constructed. Water activity, a(w), is a key factor when using enzymes in non-conventional media and the optimum value varies for different enzymes. The control system consists of a water activity sensor in the headspace of a jacketed glass reactor (equipped with narrow steel tubes to introduce air), gas-washing bottles containing blue silica gel (a(w)=0) and water (a(w)=1), a PC to monitor water activity and a programmable logic controller (PLC) to control the water activity. The system was evaluated by adjusting water activity in the medium, with a deviation from the set point of less than +/-0.05. Synthesis of cetyl palmitate, under controlled water activity and catalysed by two different lipase preparations, namely, Novozym 435 (immobilised Candida antarctica lipase B) and immobilised Candida rugosa lipase, were also performed. Novozym 435 catalyses reactions very well at extremely low water activity while C. rugosa lipase shows low activity for a(w)<0.5.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.