Potential of giant reed (Arundo donax L.) for second generation ethanol production

AbstractBackgroundThe production of second generation ethanol from lignocellulosic biomasses that have not had their potential fully explored as feedstock is of great importance. Arundo donax is one these biomasses. It is a promising grassy plant to be used as a renewable resource for the production of fuels and chemicals, because of its fast growth rate, ability to grow in different soil types and climatic conditions. The present study evaluated its use as feedstock for the production of second generation ethanol.ResultsInitially its chemical characterization was carried out, and a protocol for fractioning the biomass through diluted acid pretreatment followed by alkaline pretreatment was developed, providing a solid fraction which was undergone to enzymatic hydrolysis reaching 42g/L of glucose, obtained in 30h of enzymatic hydrolysis. This partially delignified material was subjected to a simultaneous saccharification and fermentation (SSF) process, resulting in an ethanol concentration of 39g/L at 70h.ConclusionsThe fermentability of the pretreated biomass was performed successfully through the conception of simultaneous saccharification and fermentation resulting in approximately 75L of ethanol per ton of cellulose

Potential of giant reed ( Arundo donax L.) for second generation ethanol production

Background: The production of second generation ethanol fromlignocellulosic biomasses that have not had their potential fully explored as feedstock is of great importance. Arundo donax is one these biomasses. It is a promising grassy plant to be used as a renewable resource for the production of fuels and chemicals, because of its fast growth rate, ability to grow in different soil types and climatic conditions. The present study evaluated its use as feedstock for the production of second generation ethanol. Results: Initially its chemical characterization was carried out, and a protocol for fractioning the biomass through diluted acid pretreatment followed by alkaline pretreatmentwas developed, providing a solid fractionwhich was undergone to enzymatic hydrolysis reaching 42 g/L of glucose, obtained in 30 h of enzymatic hydrolysis. This partially delignified material was subjected to a simultaneous saccharification and fermentation (SSF) process, resulting in an ethanol concentration of 39 g/L at 70 h. Conclusions: The fermentability of the pretreated biomasswas performed successfully through the conception of simultaneous saccharification and fermentation resulting in approximately 75 L of ethanol per ton of cellulose

Chemical pretreatment of Arundo donax L. for second-generation ethanol production

Background: Pretreatment of lignocellulosic biomass is essential for using it as a raw material for chemical and biofuel production. This study evaluates the effects of variables in the chemical pretreatment of the Arundo biomass on the glucose and xylose concentrations in the final enzymatic hydrolysate. Three pretreatments were tested: acid pretreatment, acid pretreatment followed by alkaline pretreatment, and alkaline pretreatment. Results: The amounts of glucose and xylose released by the enzymatic hydrolysis of the Arundo biomass obtained from acid pretreatment ranged from 6.2 to 19.1 g/L and 1.8 to 3.1 g/L, respectively. The addition of alkaline pretreatment led to a higher yield from the enzymatic hydrolysis, with the average glucose concentration 3.5 times that obtained after biomass hydrolysis with an acid pretreatment exclusively. The use of an alkaline pretreatment alone resulted in glucose and xylose concentrations similar to those obtained in the two-step pretreatment: acid pretreatment followed by alkaline pretreatment. There was no significant difference in 5-hydroxymethylfurfural, furfural, or acetic acid concentrations among the pretreatments. Conclusion: Alkaline pretreatment was essential for obtaining high concentrations of glucose and xylose. The application of an alkaline pretreatment alone resulted in high glucose and xylose concentrations. This result is very significant as it allows a cost reduction by eliminating one step

Melhoramento genético visando a qualidade do grão de aveia

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Capacidade combinatória de genótipos de milho para tolerância ao encharcamento do solo

No sul do Brasil, a cultura do milho pode ser uma alternativa de cultivo para áreas de várzea; entretanto, o desenvolvimento de genótipos tolerantes ao encharcamento é condição fundamental para viabilizar economicamente esta opção. O objetivo do presente trabalho foi determinar a capacidade geral e específica de combinação e os efeitos recíprocos para tolerância ao encharcamento do solo de genótipos de milho. A análise foi baseada em um cruzamento dialélico envolvendo quatro linhagens: duas tolerantes ao encharcamento do solo (CT954280 e CT954330) e duas sensíveis (CT966200 e CT966208). O trabalho experimental foi realizado durante os anos de 2000 e 2001 em casa de vegetação localizada na Embrapa Clima Temperado, Pelotas, RS. As variáveis analisadas foram matéria seca da raiz, matéria seca da parte aérea, estatura de planta, comprimento de raiz e conteúdo de clorofila na folha. Os resultados demonstraram a existência de variabilidade genética entre os genótipos estudados, sendo que ambos os efeitos aditivos e não aditivos foram de importância na determinação da herança da tolerância ao encharcamento em milho. A escolha do genitor feminino é fundamental para a obtenção de híbridos tolerantes, uma vez que o efeito materno observado foi elevado. Dentre os dois genótipos tolerantes analisados, a linhagem CT954330 foi a que apresentou a maior CGC e pode ser indicada como genitor preferencial em cruzamentos que visem incrementar a tolerância ao encharcamento.In southern Brazil, corn could be an alternative for cultivation in flooded areas. However, the development of genotypes tolerant to flooding is fundamental to make this option economically feasible. The objective of this paper was to determine the general and specific combining ability and reciprocal effect for flooding tolerance in corn genotypes. The analysis was based on a Diallel cross among four inbreds: two flooding tolerant (CT954280 and CT954330) and two sensitive inbreds (CT966200 and CT966208). The experiment was conducted in 2000 and 2001 under greenhouse conditions at Embrapa Clima Temperado, Pelotas, RS. Root dry matter, plant dry matter, plant high, root length, and leaf chlorophyll content were measured. Genetic variability among the inbreds was detected. Both additive and non-additive effects were important in the determination of the inheritance of flooding tolerance in corn. The correct choice of the female parent is fundamental for tolerant hybrids production, since maternal effects were relevant. Among the analyzed genotypes, the inbred CT954330 presented the highest GCA and may be indicated as a preferential progenitor in crossings that aim to increase flooding tolerance

Capacidade combinatória de genótipos de milho para tolerância ao encharcamento do solo

No sul do Brasil, a cultura do milho pode ser uma alternativa de cultivo para áreas de várzea; entretanto, o desenvolvimento de genótipos tolerantes ao encharcamento é condição fundamental para viabilizar economicamente esta opção. O objetivo do presente trabalho foi determinar a capacidade geral e específica de combinação e os efeitos recíprocos para tolerância ao encharcamento do solo de genótipos de milho. A análise foi baseada em um cruzamento dialélico envolvendo quatro linhagens: duas tolerantes ao encharcamento do solo (CT954280 e CT954330) e duas sensíveis (CT966200 e CT966208). O trabalho experimental foi realizado durante os anos de 2000 e 2001 em casa de vegetação localizada na Embrapa Clima Temperado, Pelotas, RS. As variáveis analisadas foram matéria seca da raiz, matéria seca da parte aérea, estatura de planta, comprimento de raiz e conteúdo de clorofila na folha. Os resultados demonstraram a existência de variabilidade genética entre os genótipos estudados, sendo que ambos os efeitos aditivos e não aditivos foram de importância na determinação da herança da tolerância ao encharcamento em milho. A escolha do genitor feminino é fundamental para a obtenção de híbridos tolerantes, uma vez que o efeito materno observado foi elevado. Dentre os dois genótipos tolerantes analisados, a linhagem CT954330 foi a que apresentou a maior CGC e pode ser indicada como genitor preferencial em cruzamentos que visem incrementar a tolerância ao encharcamento.In southern Brazil, corn could be an alternative for cultivation in flooded areas. However, the development of genotypes tolerant to flooding is fundamental to make this option economically feasible. The objective of this paper was to determine the general and specific combining ability and reciprocal effect for flooding tolerance in corn genotypes. The analysis was based on a Diallel cross among four inbreds: two flooding tolerant (CT954280 and CT954330) and two sensitive inbreds (CT966200 and CT966208). The experiment was conducted in 2000 and 2001 under greenhouse conditions at Embrapa Clima Temperado, Pelotas, RS. Root dry matter, plant dry matter, plant high, root length, and leaf chlorophyll content were measured. Genetic variability among the inbreds was detected. Both additive and non-additive effects were important in the determination of the inheritance of flooding tolerance in corn. The correct choice of the female parent is fundamental for tolerant hybrids production, since maternal effects were relevant. Among the analyzed genotypes, the inbred CT954330 presented the highest GCA and may be indicated as a preferential progenitor in crossings that aim to increase flooding tolerance

Technological characterisation of wood from Australian red cedar after first thinning of a plantation at five years

Australian red cedar (Toona ciliata M. Roem.) is a forest species planted in Brazil especially for lumber production. This study aimed to evaluate technological properties of the wood after selective first thinning of a plantation 5 years after planting. The technological properties evaluated were: (i) physical – apparent specific mass at 12% moisture content and shrinkage; (ii) mechanical – modulus of elasticity (E), modulus of rupture (σ), and brittleness; (iii) weathering; (iv) surface macrostructure – colour and roughness; (v) chemical – soluble and insoluble lignins, and holocellulose and ash contents; and vi) thermal – thermogravimetric analysis and calorific value. Apparent specific mass was 380 g m−3; the calculated shrinkage anisotropy of 1.04 and swelling anisotropy of 1.14 fit the classification ‘excellent quality’; the elasticity modulus was calculated as 4 700 MPa, and strength to flexion was 45 MPa. The mechanical properties other than brittleness were not compromised with weathering exposure. However, the accelerated weathering testing as a simulation of natural weathering showed modified colour of the wood and reduction of the mechanical properties. The calorific value of the wood (4 634.03 Kcal g−1) was similar to that reported for other fast-growing woods at even more advanced planting ages. Thermal stability of the wood was comparable to other fast-growing species used for energy purposes, owing especially to high holocellulose content. Keywords: accelerated weathering; calorific value; holocellulose; thermal stability; wood characteristic

Valoração do rejeito do processo do carvão: estudo preliminar

O presente trabalho tem como objetivo caracterizar os rejeitos do processamento do carvão e sintetizar sólidos que posteriormente serão analisados para aplicações na remoção de contaminantes em efluentes. Cabe salientar, que este estudo faz parte do projeto “Valoração do Rejeito do Processamento do Carvão Aplicado ao Tratamento de Efluentes” do grupo de pesquisa “Tecnologias e Soluções Sustentáveis”, portanto, resultados preliminares da pesquisa

Las Provincias : diario de Valencia: Año 67 Número 20550 - 1932 Agosto 23

O objetivo deste trabalho foi determinar frações de fibra em genótipos de aveia e avaliar o potencial do NIRS, utilizando grãos inteiros e moídos. Grãos descascados, inteiros e moídos, dos genótipos UFRGS 7, UFRGS 14, UFRGS 17 e de 99 linhagens recombinantes F7, de UFRGS 7 x UFRGS 17, foram analisados quanto aos teores de fibras total, solúvel e insolúvel, pelo método enzimático gravimétrico. Amostras de grãos, descascados inteiros e grãos moídos, foram também analisadas pelo NIRS. Os resultados indicaram que a utilização do NIRS, para avaliação do teor de fibras a partir de grãos inteiros, é eficaz e pode ser empregada na seleção desse caráter em aveia.The objective of this work was to determine fiber fraction in oat genotypes and to evaluate the use of NIRS with whole and ground groats. Whole oat groats of UFRGS 7, UFRGS 14 and UFRGS 17 and 99 F7 recombinant inbred lines from UFRGS 7 x UFRGS 17, were analyzed for total fiber, soluble fiber and insoluble fiber contents, by gravimetric-enzymatic method. Samples of whole and ground groats, were also analyzed by NIRS. The results showed that the NIRS method was efficient to determine fiber content using whole grain, and it is possible to use it for selection in oat

Chemical pretreatment of Arundo donax L. for second-generation ethanol production

Background: Pretreatment of lignocellulosic biomass is essential for using it as a raw material for chemical and biofuel production. This study evaluates the effects of variables in the chemical pretreatment of the Arundo biomass on the glucose and xylose concentrations in the final enzymatic hydrolysate. Three pretreatments were tested: acid pretreatment, acid pretreatment followed by alkaline pretreatment, and alkaline pretreatment. Results: The amounts of glucose and xylose released by the enzymatic hydrolysis of the Arundo biomass obtained from acid pretreatment ranged from 6.2 to 19.1 g/L and 1.8 to 3.1 g/L, respectively. The addition of alkaline pretreatment led to a higher yield from the enzymatic hydrolysis, with the average glucose concentration 3.5 times that obtained after biomass hydrolysis with an acid pretreatment exclusively. The use of an alkaline pretreatment alone resulted in glucose and xylose concentrations similar to those obtained in the two-step pretreatment: acid pretreatment followed by alkaline pretreatment. There was no significant difference in 5-hydroxymethylfurfural, furfural, or acetic acid concentrations among the pretreatments. Conclusion: Alkaline pretreatment was essential for obtaining high concentrations of glucose and xylose. The application of an alkaline pretreatment alone resulted in high glucose and xylose concentrations. This result is very significant as it allows a cost reduction by eliminating one step