Wanderley Dantas dos Santos

The Biotechnology Roadmap for Sugarcane Improvement

Due to the strategic importance of sugarcane to Brazil, FAPESP, the main São Paulo state research funding agency, launched in 2008 the FAPESP Bioenergy Research Program (BIOEN, http://bioenfapesp.org). BIOEN aims to generate new knowledge and human resources for the improvement of the sugarcane and ethanol industry. As part of the BIOEN program, a Workshop on Sugarcane Improvement was held on March 18th and 19th 2009 in São Paulo, Brazil. The aim of the workshop was to explore present and future challenges for sugarcane improvement and its use as a sustainable bioenergy and biomaterial feedstock. The workshop was divided in four sections that represent important challenges for sugarcane improvement: a) gene discovery and sugarcane genomics, b) transgenics and controlled transgene expression, c) sugarcane physiology (photosynthesis, sucrose metabolism, and drought) and d) breeding and statistical genetics. This report summarizes the roadmap for the improvement of sugarcane.

Bioenergy and the Sustainable Revolution

In this chapter, we will discuss some unexpected consequences that renewable energy policies might present for technological development and present an overview about the main current approaches to produce Biofuels. The technological barriers and alternatives investigated to overcome them are also discussed. In the first section, we argue that such radical changes in the way we think and sustain our development might imply that we are facing a new revolution in our energy production system. We proceed to elucidate some principles that are likely to determine the ideal and actual scenario of renewable fuels, including how ethanol can succeed and how biotechnological approaches chosen to produce second generation ethanol imply coping with the high complexity of lignocellulosic material. We also discuss the principles of biodiesel production, the importance of this incipient biofuel might offer to the setting of ethanol industry. Finally, we discuss the advantages and main perspectives in the short-term developments expected by the promising area of themochemistry to biofuel production.

Trans-aconitic acid inhibits the growth and photosynthesis of Glycine max

Grasses producing trans-aconitic acid, a geometric isomer of cis-aconitic acid, are often used in Glycine max rotation systems. However, the effects of trans-aconitic acid on Glycine max are unknown. We conducted a hydroponic experiment to evaluate the effects of 2.5-10u202fmM trans-aconitic acid on Glycine max growth and photosynthesis. The results revealed that the enhanced H2O2 production in the roots increased the membrane permeability and reduced the water uptake. These effects culminated with a reduced stomatal conductance (gs), which seems to be the main cause for a decreased photosynthetic rate (A). Due to low gs, the limited CO2 assimilation may have overexcited the photosystems, as indicated by the high production of H2O2 in leaves. After 96u202fh of incubation, and due to H2O2-induced damage to photosystems, a probable non-stomatal limitation for photosynthesis contributed to reducing A. This is corroborated by the significant decrease in the quantum yield of electron flow through photosystem II in vivo (ΦPSII) and the chlorophyll content. Taken together, the damage to the root system and photosynthetic apparatus caused by trans-aconitic acid significantly reduced the Glycine max plant growth.

Lignin-induced growth inhibition in soybean exposed to iron oxide nanoparticles

Plants are occasionally exposed to environmental perturbations that limit their growth. One of these perturbations is the exposure to and interaction with various nanoparticles (NPs) that are discarded continuously into the environment. Hitherto, no study has been carried out evaluating the effects of iron oxide (γ-Fe2O3) NPs on soybean growth and lignin formation, as proposed herein. For comparative purposes, we also submitted soybean plants to non-nanoparticulate iron (FeCl3). Exposure of the plants to γ-Fe2O3 NPs increased cell wall-bound peroxidase (POD) activity but decreased phenylalanine ammonia lyase (PAL) activity due, probably, to the negative feedback of accumulated phenolic compounds. In contrast, FeCl3 decreased cell wall-bound POD activity. Both γ-Fe2O3 NPs and FeCl3 increased the lignin content of roots and stems. However, significant lignin-induced growth inhibition was noted only in stems after exposure to NPs, possibly due to changes in lignin monomer composition. In this case, γ-Fe2O3 NPs decreased the guaiacyl monomer content of roots but increased that of stems. The high levels of monomer guaiacyl in stems resulting from the action of γ-Fe2O3 NPs decreased syringyl/guaiacyl ratios, generating more highly cross-linked lignin followed by the stiffening of the cell wall and growth inhibition. In contrast, FeCl3 increased the contents of monomers p-hydroxyphenyl and syringyl in roots. The observed increase in the syringyl/guaiacyl ratio in plant roots submitted to FeCl3 agrees with the lack of effect on growth, due to the formation of a less condensed lignin. In brief, we here describe that γ-Fe2O3 NPs and FeCl3 act differently in soybean plants.

Ten Simple Rules for Developing a Successful Research Proposal in Brazil

Writing well is fundamental to publishing and having a successful scientific career [1], and being able to write a good research proposal is critical for obtaining financial support [2]. In emerging economies, such as Brazil, it is necessary to confront drawbacks not encountered in high-income countries [3]. The developing world has growing investments in science, technology, and innovation in many areas [4–6], including computational biology [7]. These investments have produced positive results in scientific quality in developing countries [8]. Although this is remarkably positive, the emergence of high-level research groups creates a highly competitive environment. We suggest a roadmap of ten simple rules for writing a consistent and convincing research project, which may be useful for researchers in Brazil and other emerging economies. There are several funding agencies in Brazil, and two of them—the National Council for Research Development (CNPq) and the Sao Paulo Research Foundation (FAPESP)—are used as examples of how proposals can be better adjusted in order to be successful. The latter represents the state funding agencies. Our ten rules will consider these agencies as the generic targets of proposals. When describing the ten rules below, we consider applications for research grant proposals and for MSc and PhD fellowships.

Phenolic Compounds in Plants: Implications for Bioenergy

Lignin is a copolymer of three main hydroxycinnamyl alcohols identified as p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) units. The highly condensed matrix (core lignin) may also be associated with low-molecular phenolics as hydroxycinnamic acids mainly p-coumaric, caffeic, ferulic, and sinapic acids dubbed noncore lignins. Lignin confers hydrophobicity and mechanical and chemical strength for tissues, providing a barrier against the attack of pathogens and herbivores. The content and composition of lignin are strongly affected by biotic and abiotic stresses. Besides core and noncore lignin, free phenolic compounds perform a relevant activity in response to plant stresses. The toxicity of allelochemicals is partially due to their ability to bind and inhibit enzyme activities. The presence of lignin imposes a physical barrier to the action of enzymes in saccharification of plant cell wall polysaccharides to the production of cellulosic ethanol. The presence of endogenous phenolic compounds as well as treatments to degrade lignin, in turn, release phenolic compounds that adsorb and inhibit cellulases, xylanases, and accessory enzymes. This chapter provides basic information on phenolic compounds of interest to support the sustainable use of alga and plant biomasses as raw materials for the production of biofuels discussing the main approaches ongoing to reduce their negative impact in biomass saccharification.