A biocatalyst discovered by Brazilian researchers has the potential to increase renewable biofuel output by removing obstacles in technology and production processes, as well as enhancing the manufacturing of bioplastics and biopolymers.
“After three and a half years of research, we identified an enzyme that can replace the traditional catalysts used in thermochemical routes for the production of aviation biokerosene,” said Letícia Zanphorlin, principal investigator for the project and head of the Brazilian Biorenewables National Laboratory (LNBR) at the Brazilian National Center for Research in Energy and Materials (CNPEM).
The enzyme discovered by the CNPEM group is OleTPRN, a “polyunsaturated alkene-producing decarboxylase belonging to the cytochrome P450 superfamily”. This metalloenzyme derived from the bacterium Rothia nasimurium promises to be the key to development of novel biotechnological routes in the production of renewable hydrocarbons for aviation from different feedstocks, such as oleaginous biomass from soy, macaw palm or corn, among others, and lignocellulosic biomass from sugarcane bagasse or straw and in the paper industry.
“Compared with conventional or chemical catalysts, the novel enzyme decarboxylates fatty acids with high yields and is selective for different sizes and types of carbon chain. It promotes deoxygenation, which is one of the trickiest processes to master in producing SAF,” Zanphorlin explained.
Oxygen can damage aircraft parts and engines, she added, which helps understand why biofuels already mass-produced in Brazil, such as ethanol and biodiesel, are not used in aviation and explains the demand for novel biocatalysts. In general, conventional catalysts used in aviation fuel production involve metals such as cobalt, platinum, nickel or palladium.
“To produce the deoxygenation reaction, these metallic catalysts must be applied under severe conditions, particularly high temperature and pressure, and can be environmentally harmful, producing technological waste and leading to financial losses,” she said.
The full article on the research is published in Proceedings of the National Academy of Sciences (PNAS).
To implement the technology, biofuel production facilities would need to be adapted, but the distribution infrastructure used by fossil fuels could be shared by renewables acting as “drop-in” fuels – substitutes for petroleum-derived hydrocarbons that would not require adaptation of engines, fuel systems or distribution networks.
The researchers are optimistic about applications in several industrial sectors. “The versatility of this enzyme makes it adaptable for use in different sectors. Alkenes are produced by enzyme reaction and are the basis for some two-thirds of the products made by the chemical industry today, especially polymers and plastics. They’re also essential to the food, cosmetics, pharmaceutical and transportation sectors,” Zanphorlin said.
