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PRODUCCIóN DE ETANOL A PARTIR DE ALMIDóN DE YUCA UTILIZANDO LA ESTRATEGIA DE PROCESO SACARIFICACIóN- FERMENTACIóN SIMULTáNEAS (SSF)
CASTA?O P,Hader I; MEJIA G,Carlos E;
Vitae , 2008,
Abstract: the world trend on fuel management, in special biofuels like ethanol, have gone to explorer new methodologies of process to optimize its production by this reason in this research is about simultaneous sacarification fermentation process and evaluate initial concentration of reducing sugar, and enzyme dosing of spirizyme fuel? are evaluated on productivity and final concentration of ethanol, under ssf (simultaneous saccharification and fermentation) process, from the product of the licuefaction process of cassava starch as substrate. the ssf process is evaluated against shf (independent saccharification and fermentation) process as control. only the factor, initial concentration of substrate presents effect over ethanol productivity. the kinetic of ssf process, in opposite to the shf process, presents time diminution of the global process around 47 y 33% to substrate levels of 150 and 200 g/l respectively. the productivity values are most at a 33% to 150 g/l of reducing sugar, and they keep constant to 200 g/l reducing sugar. the glucose in ssf strategy, at the time it is producing, it is transformed to ethanol, does not allowing to reach superior concentration to 100 g/l of reducing sugar, this implicates there is not substrate inhibition. the ethanol concentration doesn't affect the enzymatic process of sacharification. the ssf process demonstrates his technical viability on the ethanol production, to reduce time an energy requirements on the ethanol production from cassava flour.
Producción de etanol a partir de la cáscara de banano y de almidón de yuca  [cached]
JOHN F. MONSALVE G.,VICTORIA ISABEL MEDINA DE PEREZ,ANGELA ADRIANA RUIZ COLORADO
DYNA , 2006,
Abstract: En este trabajo se evaluó la hidrólisis ácida del almidón presente en yuca y de la celulosa presente en cáscara de banano y su posterior fermentación a etanol, se ajustaron los medios de fermentación para los microorganismos Saccharomyces cerevisiae NRRL Y-2034 y Zymomonas mobilis CP4. Se caracterizó la cáscara de banano, la cual posee un contenido de almidón, celulosa y hemicelulosa que representan más del 80 % de la cáscara ameritando el estudio de ésta como fuente de carbono. La hidrólisis ácida de cascara de banano produce 20 g/l de azúcares reductores. Para la Yuca con 170 g/l de almidón a; pH 0.8 en 5 horas se logra conversión completa a azúcares reductores y no se nota ningún efecto inhibitorio por parte de los cultivos realizados con cáscara de banano y yuca por la presencia de cianuro en la yuca y por la formación de compuestos tóxicos al hidrolizar la celulosa en banano. Para la fermentación realizada con Sacharomyces cerevisiae se logra una concentración de etanol de 7.92±0.31% y no se aprecia una producción considerable de etanol (menor de 0.1 g/l) para ninguno de los medios fermentados con Zymomonas mobilis.
PRODUCCIóN DE ETANOL A PARTIR DE HARINA DE YUCA EN UN SISTEMA DE HIDRóLISIS ENZIMáTICA Y FERMENTACIóN SIMULTáNEA  [cached]
HADER CASTA?O PELAEZ,MARIANA CARDONA BETANCUR,CARLOS MEJíA GOMEZ,ALEJANDRO ACOSTA CáRDENAS
DYNA , 2011,
Abstract: La necesidad mundial en la producción de biocombustibles, ha llevado a explorar nuevas estaretegias de proceso y a usar materias primas alternativas con el objetivo de optimizar la producción; por tal razón se desarrolla en esta investigación el estudio del proceso de producción de etanol a partir de harina de yuca integrando las etapas de hidrólisis enzimatica (licuefacción y sacarificación) y fermentación simultaneamente (HEFS), mediante el uso del complejo enzimático Stargen TM 001. El dise o experimental fue una Superficie de Respuesta de un dise o Central Compuesto de dos factores a dos niveles (48 - 80 ° C y 400 - 600 rpm) en la etapas de prelicuado, y luego la temperatura se ajusto a 37 °C manteniendo las otras condiciones de proceso en la integración de los etapas. La experimentacion se desarrollo con una concentración de sólidos de la harina de yuca de 28% p/v, pH de 5.3, inóculo de 0.75 g/l de la levadura Ethanol Red y una carga enzimática de 4 ml/l. La temperatura es la variable de mayor efecto sobre la producción de etanol si se compará con la agitación; aunque, ambos factores presentan significancia estadístca sobre la variable de respuesta. A 64° C y 500 rpm se alcanza una concentración de etanol de 14.6% v/v y una productividad de 2.5 g/lh (48 horas de proceso).
compara??o entre processos em SHF e em SSF de baga?o de cana-de-a?úcar para a produ??o de etanol por Saccharomyces cerevisiae
Santos, Julliana Ribeiro Alves dos;Souto-Maior, Ana Maria;Gouveia, Ester Ribeiro;Martín, Carlos;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000400027
Abstract: in this work, four different process configurations, including three simultaneous saccharification and fermentation (ssf) schemes and one separate hydrolysis and fermentation (shf) scheme, were compared, at 8% water-insoluble solids, regarding ethanol production from steam-pretreated and alkali-delignified sugar cane bagasse. two configurations included a 16 h lasting enzymatic presaccharification prior to ssf, and the third one was a classical ssf without presaccharification. cellulose conversion was higher for the delignified bagasse, and higher in ssf experiments than in shf. the highest cellulose-to-ethanol conversion (around 60% in 24 h) and maximum ethanol volumetric productivities (0.29-0.30 g/l.h) were achieved in the presaccharification-assisted ssf.
Evaluación ambiental de la producción de etanol a partir de yuca (Manihot esculenta, Crantz), variedad M-THAI 8  [cached]
VANESSA Zú?IGA CERóN,JóSE LUIS LóPEZ VELASCO,LUZ MARINA FLóREZ PARDO
El Hombre y la Máquina , 2011,
Abstract: La búsqueda de fuentes alternas de biocombustibles que no compitan con los alimentos por uso del suelo, es una necesidad no solo ética sino económica y social, que busca valorizar materias primas que no han sido explotadas en todo su potencial. En este sentido, la yuca amarga variedad M-THAI 8 ha mostrado, por estudios técnicos y de prefactibilidad económica, tener una alta viabilidad para la producción de etanol. Sin embargo, esta viabilidad debe verse desde el punto de vista ambiental (residuos sólidos y líquidos) para hacer los ajustes al proceso y disminuir la carga contaminante. Por tal motivo, a partir de estudios previos de optimización de la hidrólisis de almidón de yuca se siguieron dos protocolos para obtener etanol, cuya diferencia se encuentra en la fuente de nitrógeno en la etapa de fermentación (A. Inti y Quantum Yeast. B. sulfato de amonio), posterior a obtener el mosto, éste se destiló y a las vinazas resultantes se les hizo un análisis fisicoquímico. Como resultado de este estudio se encontró que estas contienen altos valores de DBO5 y DQO, así como de nitratos, fosfatos y sólidos totales que exceden la legislación colombiana. Para disminuir la carga contaminante desde el punto de vista del proceso se sugiere, entre otras cosas, en la etapa de presacarificación del almidón aumentar la relación sólido-líquido.
Producción de etanol a partir de harina de yuca utilizando diferentes estrategias en modo continuo
Casta?o Peláez,Hader; Mejía Gómez,Carlos; Ríos Márquez,óscar;
Producción + Limpia , 2012,
Abstract: introduction. ethanol production from starchy raw materials includes the cooking, liquefaction, saccharification, fermentation and distillation stages. the technological bases of the process have been studied, but must be improved by means of the introduction of innovations that allow an energy use reduction and higher volumetric ethanol productivity. objective. the project evaluates the ethanol production from the conversion of yucca four by means of the independent study in a continuous way of the liquefaction, saccharification and fermentation processes (lsfc), the serial connection of the three stages and the integration of the saccharification and fermentation stages in a simultaneous way (sfsc). materials and methods. the termamyl 120 l y glucoamylase amg 300l enzymes were used in the liquefaction and saccharification processes. the saccha-romyces cerevisiae yeast was used in the fermentation process. the experimental strategy evaluated the effect of the dilution rate (d h-1) (0,07, 0,1, 0,15, 0,20, 0,25 and 0,30) on the conversion and the productivity of the independent processes. with the identification of the d that allowed the integration of the processes, an evaluation was performed to the coupling of the lsfc process and in the ssfc mode. results. according to the d chosen (0,1 h-l) during the execution of the experiment, the values productivity, concentration and ethanol yield obtained were: fermentation (4,5 g/lh, 5,8 % v/v, 0,4 g/g), lsfc (5 g/lh, 5,4% v/v and 0,46 g/g) and sfsc (4,75 g/lh, 4,7 %v/v and 0,4 g/g), respectively. conclusions. developing the lsfc and sfsc strategies was possible at a d= 0,1 h-l. there were no significant differences in the productivity, concentration and yield in the strategies serially evaluated. the integration of the processes in a continuous way was technically validated.
Proceso de sacarificación y fermentación simultáneas para la conversión de la fracción celulósica del residuo de la extracción del aceite de oliva en etanol
Ballesteros, I.,Oliva, J. M.,Negro, M. J.,Manzanares, P.
Grasas y Aceites , 2002,
Abstract: In this work, the residue generated in the new two-step centrifugation process for olive oil extraction is assessed for the production of bioethanol. Both olive pulp and fragmented stones fractions comprised in such residue are analyzed and tested at laboratory scale for bioconversion to ethanol by a simultaneous saccharification and fermentation (SSF) process. Firstly, optima conditions for the enzymatic hydrolysis step of steam-exploded pretreated sustrates were determined. Then, simultaneous saccharification and fermentation process was assayed using the thermotolerant yeast Kluyveromyces marxianus in different assay conditions. For the selected conditions, 9 kg of unpretreated pulp or 6 kg of pretreated fragmented stones (both based on dry matter) would be necessary to obtain 1 liter of ethanol. En el presente trabajo se estudia la producción de etanol-combustible a partir de la celulosa contenida en las distintas fracciones (pulpa y fragmentos de huesos) que componen el residuo de la extracción de aceite de oliva mediante un proceso en dos fases. El trabajo ha consistido en una caracterización de las dos fracciones y en el estudio de la producción de etanol mediante un proceso de hidrólisis enzimática y fermentación simultáneas (SFS), a escala de laboratorio. Se ha estudiado el efecto que un pretratamiento termomecánico de explosión a vapor, previo a la etapa de hidrólisis enzimática y fermentación, tiene sobre la acción del complejo celulolítico. Por último, se han determinado las condiciones óptimas de ensayo para la sacarificación y fermentación simultáneas utilizando una cepa termotolerante de Kluyveromyces marxianus. En las condiciones de ensayo óptimas, serían necesarios 9 kg. de pulpa o 6 kg. de hueso pretratado (ambos sobre peso seco), para obtener 1 litro de etanol.
PRODUCCIóN DE ETANOL A PARTIR DE HARINA DE YUCA EN UN SISTEMA DE HIDRóLISIS ENZIMáTICA Y FERMENTACIóN SIMULTáNEA
CASTA?O PELAEZ,HADER; CARDONA BETANCUR,MARIANA; MEJíA GOMEZ,CARLOS; ACOSTA CáRDENAS,ALEJANDRO;
DYNA , 2011,
Abstract: the global need for the production of biofuels, has led to explore new strategies process and use alternative raw materials in order to optimize production, for this reason this research is developed in the study of the ethanol production process from flour cassava integrating the stages of enzyme hydrolysis (liquefaction and saccharification) and fermentation simultaneously (hefs), using the enzyme complex stargen tm 001. the experimental design was a response surface central composite design with two factors and two levels (temperature: 48 - 80 ° c and agitation: 400 - 600 rpm) in liquefaction stages previous, and then the temperature was adjusted to 37 ° c keeping the other conditions in the integration process of the stages. the experimentation was developed with a solids concentration of cassava flour of 28% w/v, ph 5.3, inoculums of 0.75 g/l of yeast ethanol red ?, and an enzyme concentration of 4 ml / l. the temperature is variable with greatest effect on the production of ethanol when compared to the agitation, though; both factors have statistic significance on the response variable. a 64 ° c and 500 rpm is reached an ethanol concentration of 14.6% v/v and a productivity of 2.5 g/lh (at 48 hours of processing)
Simultaneous Saccharification and Fermentation (SSF) of pretreated sugarcane bagasse using cellulase and Saccharomyces cerevisiae - Kinetics and modeling  [cached]
Sasikumar Elumalai,Viruthagiri Thangavelu
Chemical Engineering Research Bulletin , 2010, DOI: 10.3329/cerb.v14i1.4156
Abstract: Optimization of process variables in the bioconversion of pretreated sugarcane bagasse using cellulase and Saccharomyces cerevisiae by Simultaneous Saccharification and Fermentation (SSF) was investigated in the present study. A 23 five level Central Composite Design (CCD) experiments with central and axial points were used to develop a statistical model for the optimization of process variables such as incubation temperature , pH and fermentation time. Data obtained from Response Surface Methodology (RSM) on ethanol production were subjected to the analysis of variance (ANOVA) and analyzed using a second order polynomial equation and the contour plots were used to study the interactions among three relevant variables of the fermentation process. The fermentation experiments were carried out using an online monitored modular fermenter 2L capacity. The processing parameters setup for reaching a maximum response for ethanol production was obtained when applying the optimum values for temperature (35°C), pH (5.5) and fermentation time (114 h). Maximum ethanol concentration (4.80 g/l) was obtained from 50 g/l pretreated sugarcane bagasse at the optimized process conditions in aerobic batch fermentation. Various kinetic models such as Monod, Modified Logistic model, Modified Logistic incorporated Leudeking – Piret model and Modified Logistic incorporated Modified Leudeking – Piret model have been evaluated and the constants were predicted. Keywords: Optimization, response surface methodology (RSM), simultaneous saccharification and fermentation (SSF), ethanol, Saccharomyces cerevisiae DOI = 10.3329/cerb.v14i1.4156 Chemical Engineering Research Bulletin 14 (2010) 29-35
Evaluation of Potential Fungal Species for the in situ Simultaneous Saccharification and Fermentation (SSF) of Cellulosic Material
Vincent, M.,Pometto III, A. L.,Leeuwen, J.
Malaysian Journal of Microbiology , 2011,
Abstract: Three fungal species were evaluated for their abilities to saccharify pure cellulose. The three species chosen represented three major wood-rot molds; brown rot (Gloeophyllum trabeum), white rot (Phanerochaete chrysosporium) and soft rot (Trichoderma reesei). After solid state fermentation of the fungi on the filter paper for four days, the saccharified cellulose was then fermented to ethanol by using Saccharomyces cerevisiae. The efficiency of the fungal species in saccharifying the filter paper was compared against a low dose (25 FPU/g cellulose) of a commercial cellulase. Total sugar, cellobiose and glucose were monitored during the fermentation period, along with ethanol, acetic acid and lactic acid. Results indicated that the most efficient fungal species in saccharifying the filter paper was T. reesei with 5.13 g/100 g filter paper of ethanol being produced at days 5, followed by P. chrysosporium at 1.79 g/100 g filter paper. No ethanol was detected for the filter paper treated with G. trabeum throughout the five day fermentation stage. Acetic acid was only produced in the sample treated with T. reesei and the commercial enzyme, with concentration 0.95 and 2.57 g/100 g filter paper, respectively at day 5. Lactic acid production was not detected for all the fungal treated filter paper after day 5. Our study indicated that there is potential in utilizing in situ enzymatic saccharification of biomass by using T. reesei and P. chrysosporium that may lead to an economical simultaneous saccharification and fermentation process for the production of fuel ethanol.
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