Scientific challenges of bioethanol production in Brazil

Zhu

Journal of Environmental Sciences

et al. 2014

a b s t r a c tA pot experiment was conducted to investigate the feasibility of growing energy sugarcane (Saccharum spp.) in three different metal mine tailings (Cu, Sn and Pb/Zn tailings) amended with uncontaminated soil at different mixing ratios. The results indicated that sugarcane was highly tolerant to tailing environments. Amendments of 20% soil to Sn tailings and 30% soil to Cu tailings could increase the biomass of cane-stem for use as the raw material for bioethanol production. Heavy metals were mostly retained in roots, which indicated that sugarcane was useful for the stabilization of the tailings. Bagasse and juice, as the most valuable parts to produce bioethanol, only accounted for 0.6%-3% and 0.6%-7% of the total metal content. Our study supported the potential use of sugarcane for tailing phytostabilization and bioenergy production.

Section: Introductionmentioning

confidence: 99%

Growth and metal uptake of energy sugarcane (Saccharum spp.) in different metal mine tailings with soil amendments

Zhu

Journal of Environmental Sciences

et al. 2014

“…Based on the various technological options discussed in this article for the production of ethanol, Table 2 provides a summary of the challenges that need to be addressed by technologists 66,67 .…”

Section: Technological Challengesmentioning

confidence: 99%

Viable Feedstock Options and Technological Challenges for Ethanol Production in India

2016

Though improvements in processing and technology are important, the fluctuating price of inputs such as molasses, corn, sugar beet, sugarcane, sweet sorghum, starch, etc. and their seasonal availability play an important role in ethanol industry. As a matter of fact, the ethanol industry based on conventional resources has reached its saturation point. Technologies for ethanol production from lignocellulosics are being developed by scientists world over with the objective of exploiting the potential of a resource, which is otherwise considered a waste, to generate energy. The focus has been to produce ethanol in a cost-effective manner, besides aiming to find use of its by-products as food supplements for cattles, etc. Recent developments like adoption of technologies such as dry grind fractionation, which is now commercially viable, would reduce the cost of milling; wet milling being costintensive and dry milling requiring smaller plants.

Afr. J. Microbiol. Res.

“…Most Brazilian industrial processes utilize the Melle-Boinot method, where by yeast cells are recovered from the process and subjected to an acid wash treatment before starting a new fermentation cycle (Amorim et al, 2011). Most commercial Saccharomyces cerevisiae strains utilized in the Brazilian processes are not the result of induced D1 to D5 End genetic modifications.…”

Section: Introductionmentioning

confidence: 99%

Morphophysiological and molecular characterization of wild yeast isolates from industrial ethanol process

Viana¹,

Portugal²,

Cruz³

2017

Wild yeasts are commonly found during the fermentation process, displaying different survival and competition strategies that commonly enable their successful spread in the medium. Identifying these yeasts by biological and molecular monitoring, and knowing their traits is vital for the fermentation yield, and this can be done by simple methods such as differential mediaplating, growth rate evaluation and DNA sequencing. The aim of this work was to perform morphophysiological and molecular characterization of 14 yeast isolates from a bioethanol plant in the State of Sao Paulo, Brazil. This was done by employing different culture media to assess the growth and the morphophysiological characteristics of the isolates. The molecular characterization was also done in order to identify the samples in intra-specific levels, compared to the reference strains. The Saccharomyces cerevisiae CAT-1 and PE-2, Brazil's two main commercial strains, were used as reference. The results suggest that a single ethanol-producing unit may display a highly diversified microbiome, with the occurrence of distinctive wild yeast strains disclosing diverse morphophysiological traits, as observed in the differential media plating and growth rate assay results. The molecular characterization shows that these yeast isolates differ from the reference strains, as observed in interdelta-based PCR fingerprint banding patterns. These findings are a statement of the yeast diversity found in the fermentation process, and are of interest for the ethanol industry, being that many of the commercial strains were firstly isolated from the local biome.