Title:Production of n-Propyl Cinnamate (Musty Vine Amber Flavor) by Lipase Catalysis in a Non-Aqueous Medium
VOLUME: 1 ISSUE: 3
Author(s):Abhishek Thakur, Ashok Kumar and Shamsher S. Kanwar
Affiliation:Department of Biotechnology, Himachal Pradesh University, Summer Hill, Shimla-171 005, India.
Keywords:Cross-linking, esterification, glutaraldehyde, immobilization, lipase, n-propyl cinnamate, DMSO, silica-bound lipase, carboxyester, esterases, lipases, mono-acylglycerols, glycerol, fatty acids
Abstract:The enzymatic esterification of n-propanol with cinnamic acid was carried out with a commercial lipase
(Lipolase 100T) immobilized onto silica. The silica pretreated with 1% (v/v) glutaraldehyde showed 95% protein binding
efficiency. Esterification reactions were carried out at 45oC under shaking (160 rpm) with 75 mM: 100 mM of cinnamic
acid and n-propanol, respectively in DMSO. The maximum yield of n-propyl cinnamate (94 mM) was achieved in 2.5 h at
45oC using 25 mg of silica-bound biocatalyst. Addition of molecular sieves to the reaction mixture had little effect in
improving the ester synthesis. In esterification reaction among the tested salt ions, a pre-exposure of the silica-bound
lipase to Ca2+ and Cu2+ ions (1 mM) improved the ester yield in DMSO. The silica-immobilized lipase retained ~39% of
its original efficiency after 7th repetitive cycle of esterification. The n-propyl cinnamate synthesis when scaled up to 50 ml
batch reaction yielded 79 mM of the ester. Thus the study achieved a good yield of n-propyl cinnamate synthesis in
DMSO in a scaled-up reaction system under optimized conditions using silica-bound lipase.