Biodiesel program in Brazil: learning
curve over ten years (2005–2015)
Nogueira, L. A.H., et al., Biofuels, Bioprod. Biorefin.10: 728–737,
The biodiesel blending mandate was launched at 2005 in Brazil,
by a governmental program based mainly on sustainability concerns,
especially toward social and environmental aspects. Since 2007, B7,
i.e., 7% biodiesel in diesel, in volume terms, has been mandatory,
and B10 is the next target. In this context, this paper aims to evaluate the biodiesel program along the ten years from 2005 to 2015 in
Brazil, considering the evolution of the estimated costs and the auction prices intending to verify some tendency in a learning curve perspective. A decreasing tendency of the biodiesel production costs and
prices was observed, with a reduction of the profit margin in recent
years, suggesting a learning trend. The Progress Ratio (PR) of the
whole period was 101.7%, but in the 2011–2015, it was estimated at
59.3%. Relevant technology changes in biodiesel production process
were not verified, but the increased competitiveness in the market,
the gains of scale of plant profiles, and mainly the decrease of soybean
oil prices explain this evolution.
Protein-based drugs are used in the treatment of every
kind of malady, from cancer to heart disease to rheumatoid
arthritis. But the proteins are almost always modified with
chemical appendages that help them navigate through the
body or target specific tissues. A new study by Hao, Y., et al.,
“Molecular basis for the broad substrate selectivity of a peptide prenyltransferase,” Proc. Natl. Acad. Sci. USA, online
first, http://dx.doi.org/10.1073/pnas.1609869113, reveals an
efficient means of attaching lipids to peptides (the building
blocks of proteins). This can improve the molecules’ drug-de-livery capabilities.
“Medicinal chemistry has focused on using peptides as
scaffolds for drugs because of the ease of their production and
the chemical diversity of their amino-acid building blocks,”
said Satish K. Nair, a biochemistry professor at the University
of Illinois, Urbana-Champaign, Illinois, USA, who led the new
research with Thomas Cheatham and Eric Schmidt of the
University of Utah. “However, peptides are generally ineffective drugs because they are poorly absorbed, cannot penetrate
the blood-brain barrier, and are easily broken down,” Nair said.
Attaching lipids “improves all of these properties, enabling
peptides to be more drug-like,” he said. Current methods for
attaching lipids to peptides require the use of either harsh
chemical solvents or expensive biological catalysts.
Nair and his colleagues focused on a little-known group of
enzymes isolated from water-dwelling bacteria that have the
remarkable ability to add lipids to a wide variety of proteins. The
team performed a series of experiments on one family of these
enzymes to discover how they recognize and interact with the
peptides they modify.
The researchers discovered that one type of enzyme recognizes a simple, two-amino-acid sequence within its target
proteins. They added this motif to two peptides selected at random and exposed the peptides to the enzyme. This caused the
enzyme to add a lipid appendage to the proteins. The transformation was fast and efficient.
“Now that we have a very efficient way of attaching lipids
to peptides, this opens up the possibility of using this approach
to make large libraries of molecules that are more drug-like than
peptides,” Nair said.
New way to attach lipids to proteins
could streamline drug development