Synthesis of flavor compound ethyl hydrocinnamate by Yarrowia lipolytica lipases

Abstract

Two biocatalysts with high lipolytic activity were obtained – freeze-dried supernatant and freeze-dried biomass of Yarrowia lipolytica KKP 379. The biocatalysts were compared with Candida antarctica lipase B in the synthesis of ethyl hydrocinnamate – a flavour compound with a floral-honey aroma. Ester synthesis was completed after 2 h when 3 grams of freeze-dried biomass was used. Using smaller amounts of biomass (1.2 and 0.6 g) also allowed to achieve high ester conversion and results were comparable with those obtained for CALB used as a catalyst. Freeze-dried supernatant showed a weaker lipase activity (22.17 U/g) compared to freeze-dried biomass (46.13 U/g), which resulted in a lower conversion of 3-phenylpropionic acid to its ethyl ester, and after 36 h a conversion peaked at around 70%, then began to decrease and finally the conversion reached 50%. Moreover, antimicrobial and antioxidant properties of the synthesised ester were evaluated. Ethyl hydrocinnamate showed no antibacterial activity and weak antioxidant activity towards DPPH radical. In contrast to bacteria, the obtained compound moderately inhibited the growth of tested yeast species, where inhibition zones ranged from 10 to 16 mm.

Keywords:

• Ethyl hydrocinnamate
• flavour compound
• Yarrowia lipolytica
• lipases
• enzymatic synthesis

Disclosure statement

The authors declare that they have no conflict of interest.