In recent years, the production of renewable fuels such as biodiesel has
attracted considerable interest as an alternative to fossil fuels. The conventional alkalicatalyzed
processes of biodiesel production present a number of drawbacks to which
enzymatic processes present interesting solutions. Fungal lipases are among the most
used biocatalysts in the enzymatic synthesis of biodiesel. Different strategies are
currently under study in order to reduce the biocatalyst cost and to obtain a more robust
biocatalyst with high activity and stability. This article reviews the status and
possibilities for biodiesel production using fungal lipases, and discusses the critical
aspects that influence lipase activity and stability, including choice of raw material and
alcohols, type of biocatalyst, use of solvents, and water activity. Moreover, the
development of whole-cells as a new promising technology, the exploration of
alternative low-cost oils as potential feedstock and the evaluation of possible reactor
configurations are also reported. In conclusion, considerations on the process and an
economic efficacy analysis of industrial enzymatic biodiesel production are presented.
Keywords: Batch-Stirred-Tank Reactor, biocatalyst, biodiesel, esterification,
ethanol, ethyl ester, free fatty acids, fungal lipases, glycerol, hydroesterification,
immobilized lipase, methanol, methyl ester, microbial oil, Packed-Bed Reactor,
transesterification, triglycerides, vegetable oils, waste oil, whole-cells.
