Research study on bioethanol weighs alternatives for second generation biofuels

Increased knowledge about genes that may increase sugarcane biomass and resistance to hydric stress includes complementary use of other crops established in Brazil.

By Fernando Cunha, in Tokyo

Agência FAPESP – Recent discoveries about plants that may be considered alternative and complementary to the production of second generation ethanol obtained from biomass were reported during the Japan-Brazil Symposium on Research Collaboration.

Organized jointly by FAPESP and the Japan Society for the Promotion of Science (JSPS), the event was held at Rikkyo University March 15-61, with support from the Embassy of Brazil in Tokyo.

In his lecture entitled Outlook for bioethanol research in Brazil Marcos Silveira Buckeridge, professor at the Biosciences Institute of the University of São Paulo, laid out the major advances achieved through experiments with genes capable of increasing the production of biomass from plants like corn, rice, sorghum, miscanthus and sugar beet.

Supported by agricultural data on crop cycles, yields and energy balance, Buckeridge and his team at the National Institute of Science and Technology of Bioethanol – one of the national institutes of science and technology established in the state of São Paulo in partnership with the National Council for Scientific and Technological Development (CNPq) – developed the Crop Bioenergy Performance Index (CBPI) to rate the performance of each of the crops in producing bioenergy.

According to the researcher, the CBPI can offer strategic information about the direction Brazil might like to take. “Sugarcane, sorghum and corn may be planted and are good solutions for Brazil,” he said.

“We already obtained good results from a series of experiments conducted with a set of genes for the second generation of ethanol,” Buckeridge added. “We analyzed three months’ of production cycles and know how to improve the process through which the plant transforms light energy into biomass using genes that we have already identified with this capacity,” he explained.

The next step will be to conduct the inverse process to improve the production of biomass starting with the results of sugarcane gene sequencing currently underway under the FAPESP Bioenergy Research Program (BIOEN).

According to Buckeridge, this stage will include information from the sugarcane genome in an attempt to pinpoint the genes he is utilizing in his experiments in the plant’s so-called “giant chromosomes” that have already been sequenced.

The researchers have identified the sugarcane genes that are involved in the rupture of the plant’s cell wall, a process that is important for obtaining cellulosic ethanol, and will use the same approach to manage the plant’s increased resistance to hydric stress.

“This super-plant, a much more productive sugarcane that may be developed within the scope of the BIOEN-FAPESP Program, may prevent the need to expand sugarcane fields and open up space for the planting and recovery of forests located up to 2 km from the sugarcane files, a parameter determined by the project, which may be altered,” he said.

Thus, the negative balance between sugarcane’s capacity to assimilate carbon dioxide (CO2) expressed as 7.4 tons/hectares/year, and the storage of carbon from these forests (8.2 t/ha/year) may be neutralized by the recovery or planting of nearly 800 hectares of forests near the sugarcane fields, promoted by the researchers from the BIOTA-FAPESP Program.

With a focus on agriculture, Buckeridge’s lecture described the current scenario of the Brazilian agricultural system, the history of sugarcane production in Brazil, and some of the challenges, such as adapting to global climate change, that prompted the higher research output in an effort to increase the sustainable production of ethanol in Brazil starting in 2006.