last blog entry? :(

For this last blog entry we were asked to write about the posters we reviewed during our first BioMinds Research Day and Poster Session. It was pretty cool to get to review my peers’ posters. It was a new experience and  I had never judged research projects at a science fair or anything.

We were supposed to review 3 posters but because of time constraints and lack of flowing space I was only able to review two.

The first poster I reviewed belonged to L. C. Almodovar. Her poster title was ‘Heavy Metal Removal in Water Treatment Plants in Mayagüez and Adjuntas’. It complied with each one of the poster requirements and was well organized. Ms. Almodovar showed ample domain of the topic answering mu questions appropriately. I found her topic very interesting because I had worked with water quality in previous research projects and was able to understand her work.

The second poster I reviewed belonged to Arnaldo Carrera and Carlos Acevedo. The title was  ‘Characterizing Inositul 1,4,5-triphosphate’.  The poster was well prepared and complied with all requirements. I’m a chemical engineering student, and have never dealt with genetic engineering or cell physiology yet this student was able to explain his work to me in a simple yet interesting enough way for me to understand it and keep my attention. So he definitely proved he had complete domain of the topic and he also answered patiently all of the questions I had to ask for not being a biology student.

Well bloggers I hope I could keep writing through this medium after I finish my period within the BioMinds program but, in case this is isn’t so, it was cool becoming an rookie blogger during this year and a half long research experience. I wish you all the best.

Cheers,

Di

1st Assessment

Since my presented objectives were long-term goals, I have not met them.  They were proposed to be achieved by the end of the semester. Yet, we have been making some progress towards these objectives. Concepts from all of our proposals were merged and we have developed a statistical study directed to find the optimum growth conditions during fermentations with P. Stipitis. Therefore, I could say that on the progress scale from 1 to 5 we would get a 2. The main difficulty here is going to be time because the poster session date is early in the semester considering our objectives were set for the end of it.

Eitherway, we have submitted our abstract for the poster session. If you are interested in our topic of producing cellulosic ethanol, you may read our abstract provided below.

Bioprocess Engineering Studies to Improve Production of Cellulosic Ethanol

Optimizing xylose-fermentation processes involving Pichia Stipitis

Biofuels stand today as a serious solution to the volatilely-priced fossil fuels, first as very poor producers of greenhouse gases (GHG) and second, as being less energy-intensive in process and production stages than their counterparts (Lago et.al., 2006). Obtaining ethanol from sugar cane bagasse is regarded as a possible source of this alternative fuel for two reasons: it does not hinder food accessibility and, reduces solid waste generation from sugar cane processing. Cellulose, hemicellulose and lignin are the main components of bagasse: cellulose can be hydrolyzed into glucose yet hemicellulose is hydrolyzed into glucose and other pentoses, where xylose is abundant. Unlike glucose, xylose can only be fermented by a limited number of yeast strains. A previous screening study showed that Pichia stipitis NRRL Y-11545, was the best xylose fermenting strain, although it was found to have a poor growth rate during experiments. This project aims to study the effects of environmental factors on P. stipitis growth under anoxic conditions in batch fermentation reactors. Xylose fermentation by P. stipitis can be optimized by performing fermentations for each selected parameter combinations in order to achieve higher ethanol yields, cell growth and substrate consumption. Maximum and minimum values in a 23 factorial design for initial xylose concentration, temperature and agitation are 50-80 g/L, 30-40°C, and 80-125 rpm respectively. A minimum of two runs will be run at each of these values in order to observe the interaction of these variables with each other. To control the inoculum quality, the initial culture will be preserved in glycerol so that each batch run will have an inoculum with the same effectiveness. Malt extract will be added as a new ingredient to the batch culture media. Batch culture data for the effect of the combinations will be analyzed by means of periodical optical density measurements, dry biomass weighting and HPLC analysis for xylose and ethanol. The factorial design experiments will be analyzed using an ANOVA (Analysis of Variance) with MINITAB, a statistical software. Previous experiments found in literature have confirmed that higher initial xylose concentration increases the ethanol production, since higher amount of cells are available for ethanol conversion. In addition, experiments executed around 30˚C have produced higher overall yield. Finally, low agitation level (50-100 rpm) has been proven to achieve higher ethanol production.

Local engineer proposes green-based economic development plan

Check out this site.

http://www.caribbeanbusinesspr.com/news02.php?nw_id=937&ct_id=28

Comienzo del final: continuación del futuro

Es    Este semestre estaré presentando una propuesta individual. El propósito de la misma es hallar las condiciones óptimas de temperatura y concentración de azúcar para el crecimiento de la levadura P. Stipitis, la cual no ha sido alterada genéticamente, en la fase de fermentación.

Para el final del semestre espero

1) haber hallado las condiciones idóneas de crecimiento

2) Integrar mis resultados con los de compañeros que estudien los niveles de oxigenación

3) Obtener crecimientos vigorosos de nuestra levadura para lograr fermentaciones azucares a etanol más exitosas y mejor calidad de data de peso seco de biomasa.

Esto complementará nuestro proyecto del semestre anterior ya que mejorará el crecimiento de P. Stipitis en estado anóxico lo cual permitirá estudios más exitosos y reproducibles sobre la cinética de la fermentación de xilosa por esta levadura.

Esperamos desarrollar una nueva técnica de cultivo la cual consiste en concentrar por centrifugación la biomasa obtenida luego de un cultivo inicial. Con esto esperamos también mejorar la rapidez de crecimiento de P. Stipitis.

November, Novembre, Noviembre

Hey there,

Against all odds this month we were able to finish our research project and we even prepared a poster. Here’s a briefing of our findings.

First, for the sake of a recap (da cappo) I will remind you a few things. Ethanol has been produced by fermenting sugar cane cellulose since almost forever, at least 30 years if you are thinking about Brazil using ethanol as fuel and many more if you are thinking about rum production. Yet, when ethanol is produced only from cellulose, many parts of the cane are wasted. These wastes are either burned or sent to fill up a space at a landfill. Most of it is known as bagasse which is rich in hemicellulose and lignocellulose. The objective of our project is to make use of these parts of the cane to reduce waste. Now, sugars obtained fron lignin hydrolization have been found to be very hard to ferment by wild yeasts. Nonetheless, hemicellulose can be hydrolized into xylose and glucose. Fermenting glucose is piece of cake (relatively) but xylose fermentation is a tougher case and this case is what we chose as our project.

Unlike glucose, xylose can only be fermented by a limited number of wild yeast strains. During this project, the main objective is to determine the kinetics and ethanol yields of xylose-fermenting yeast strains Pichia stipitis, Pachysolen tannophilus and Candida shehatae to screen for the most efficient xylose-fermenting strain. Batch fermentations for each strain were conducted at a pH range between 4.5 and 5.5 and, temperature and agitation of 32 C and 115 rpm, respectively. Batch culture data and ethanol production were determined by means of periodical optical density measurements, dry biomass weighing and HPLC analysis for xylose and ethanol. 

The maximum specific growth rate, μ_max, overall ethanol yield, Y_P/S and Y_P/X, and overall biomass yield, Y_X/S , were obtained for each strain. Y_P/S is defined as ethanol yield as a function of substrate (xylose) concentration, Y_P/X as  ethanol yield as a function of yeast cell concnetration and as Y_X/S cell concentration as a function of xylose concentration. During experimentation, Pachysolen strain showed random data variability so we were not able to obtain coherent results for it. We did obtain results for Candida and Pichia.
For Pichia stipitis and Candida shehatae μ_max values were 0.036 h^-1 and 0.0586 h^-1, respectively. Based on data analysis, Pichia stipitis offers the highest ethanol yield from xylose fermentation.

The next stage of this project will be to combine Pichia Stipitis and an effective glucose fermenting yeast in a co-fermentation of xylose and glucose. The objective of this stage is to develop a process in which hemicellulosic and cellulosic elements of sugar cane can be employed simultaneously in the production of ethanol.

I hope this was informative and interesting enough for you. Happy holidays. Joyeux Noël =)

Hunting for October

Hey bloggers,
We have good news for this month of October. Facilities in our lab were improved and we were able to start performing our fermentation runs scheduled for October. There were several mishaps with instrumentation but that is an expected side of using an instrument for the first time. After those first steps we’ve been able to improve our culture transfer and sample analysis techniques. Personally, I have been able to make culture transfers successfully and have been able to take part in each of the lab procedures that embody our fermentation process. In addition, we have learned to adapt our experimental procedures according to gathered results and available resources. I think this last one is a very valuable lesson. The lab group had several goals to hunt for in October and, up to today, very important ones have been met. And, before the month ends there still time to meet those that haven’t been reached, including preparing a research poster to be presented at national conference. Alluring, isn’t it?  I think we deserve a 4. 

Preliminary results confirm previous expectations of Pichia Stipitis being the best xylose fermenting yeast of our three strains. Upcoming xylose fermentation runs will give more information regarding these results. If the designed experimentation routine is completed effectively, it will be possible for this lab group to propose a new co-fermenting pair of yeasts to obtain ethanol from parts of vegetation that usually just occupy space in a trash can or a landfill.

Entrada de Septiembre

Disculpen la tardanza bloggers.

En este período hemos sido entrenados en tomar el peso de la biomasa en una muestra. Esta técnica nos servira’ como otra de medida del progreso de nuestra fermentacion.

Nuestro laboratorio aun no esta’ apto para la experimentación. Nuestro “hood” de ascepcia esta’ averiado. No tenemos autoclave y el bioreactor tiene una bomba dañada, ademas el techo del lab tiene muchas goteras. Esto ultimo promueve la humedad y la proliferacion de organismos que pueden contamnar nuestros cultivos. Debido a estas razones no hemos podido empezar nuestra experimentación. Lamentablemente, la burocracia hace aun mas lento el proceso. Creo que al final hemos logrado cumplir con algunos objetivos ya que hemos empezado a diseñar nuestros propios experimentos y hemos aprendido nuevas tecnicas de cultivo.  Personalmente, nos daria un 3.

Aterrizando

Wow, parece que llegué hace mucho de mi internado en UC Berkeley, CA, pero han pasado solo dos semanas. Estuve trabajando en un proyecto relacionado a otra fuente alterna de energía, las celdas de hidrógeno. Definitivamente, fue muy diferente a lo que es mi proyecto acá en PR en el cual trabajo con levaduras y producción de etanol como biocombustible. Allá, mis experimentos no trataban con ente vivo alguno. El único compuesto orgánico que utilicé fue iso-propanol para limpiar mis herramientas de trabajo. Se trataba de estudiar con la técnica de NMR en Estado Sólido nuevos materiales cerámicos inorgánicos como medios conductores de protones. Fue muy interesante practicar esta técnica. Primero, es retante ya que muy poca gente la utiliza debido a que es su altamente compleja. Segundo, está muy relacionada a la cuántica, ya que los efectos del NMR se observan a escala atómica o subatómica, y esos pequeñisimos sistemas llaman mucho mi atención ya que solía trabajar en simulaciones de sistemas a esa escala. Fue una experiencia muy grata.

Ya después de aterrizar y de reunirme con mi grupo, se me ha asignado un proyecto un poco distinto al del semestre pasado ya que esta vez tendré mi propia cepa de levaduras para trabajar. Cada uno de mis compañeros de lab subgraduados tendrá una cepa distitnta. Cultivaremos nuestras cepas, con las mismas haremos experimentos de fermentación de celulosa y xilosa. Luego compararemos las efectividades en fermentación de cada cepa para así determinar cuál es la más apropiada. Espero alcanzar lo siguiente:

1) Aprender a no matar mi cultivo

2) Dominar la técnica de HPLC.

3) Entender la diferencia entre los metabolismos de glucosa y xilosa de cada cepa.

4) Lograr completar 2 o más experimentos de fermentación para tener data y compararla con la de mis compañeros.

5) Ser más independiente en mi investigación.

Por lo tanto, comparado con el anterior semestre, éste será un tanto diferente ya que está vez cada uno estará a cargo de sus experimentos, en lugar de que todos trabajemos en el mismo. Además, se añade xilosa los azúcares a ser metabolizados en etanol.

En adición a esto estaremos practicando una nueva técnica de secado para determinar la masa restante de las bacterias. Además, aprenderemos a determinar los modelos cinéticos de nuestro sistema ya que cuando se trabaja con materia viva que lleva a cabo una reacción, el proceso es distinto al de una reacción química sin intervención de células.

Son muchas las expectativas, ya veremos lo que el tiempo y las condiciones nos permitan lograr.

Other alternative energy source: Hydrogen Fuel Cells Apps.

Fuel Cells 2000’s Fuel Cell Technology Update – July 2008

The Fuel Cell Insider is here! Fuel Cells 2000’s foray into the blog world has finally arrived – please check out the Fuel Cell Insider at www.fuelcellinsider.org and spread the word.   Don’t worry, you will still get your monthly news from the Fuel Cell Technology Update, but the Fuel Cell Insider will supplement your hunger for fuel cell knowledge with opinion/editorial pieces and analyses, speeches and presentations, plus guest posts from experts in the field.  The purpose is not only to inform, but to engage, and ultimately to contribute to the global debate on energy policy for this century and the next.  We will succeed only with your help.

To unsubscribe to this newsletter, please see the end of this message.

TRANSPORTATION APPLICATIONS

Honda Begins Production of FCX Clarity.

Honda Motor Co., Ltd. has started production of the new FCX Clarity, with the first vehicle meeting U.S. specifications coming off the new dedicated fuel cell assembly line at the Honda Automobile New Model Center in Japan.  Lease sales are scheduled to begin in July in the U.S. and this fall in Japan.

http://world.honda.com/news/2008/4080616New-FCX-Clarity/

Toyota‘s FCHV-adv Achieves 515 Miles on Single Tank.

Toyota Motor Corporation has developed a new version of its fuel cell hydrogen vehicle, the FCHV-adv, which can travel about 515 miles on a single hydrogen fueling.  Toyota doubled the pressure of its hydrogen storage tanks to 70 megapascals and incorporated a higher-performance fuel cell, enhanced regenerative braking to recharge the battery while slowing down, and a more efficient auxiliary power system to achieve a 25% improvement in fuel economy.  The FCHV-adv has already received government approval and will be available for leasing in Japan later in 2008.

http://www.automotive-business-review.com/article_news.asp?guid=12711C0B-E9E1-40D7-9994-8C47DBB9FF32

London Cabs Go for the Green at the 2012 Olympics.

London black cabs will be powered by hydrogen fuel cells for the 2012 Olympics, as part of the UK government’s Technology Strategy Board’s £23 million program that includes an innovative low carbon vehicle development program.  The fuel cell/battery hybrid cabs will be able to operate for a full day without refueling, and can achieve speeds up to 75 mph.  The project involves Intelligent Energy, Lotus Engineering Ltd, London Taxis International (LTI) Ltd. and TRW Conekt. http://www.renewableenergyfocus.com/articles/fuelcells/bus_news/080618_cabs.html

STATIONARY APPLICATIONS

Twelve Fuel Cells to Power New Freedom Tower in New York City.

UTC Power was selected by the New York Power Authority (NYPA) to supply 12 fuel cells totaling 4.8 megawatts of power for the Freedom Tower and three other new towers under construction at the World Trade Center site in lower Manhattan. The PureCell® Model 400 units will constitute one of the largest fuel cell installations in the world and are set to be delivered beginning in January 2009. http://www.utcpower.com/fs/com/bin/fs_com_Page/0,11491,0278,00.html

Fuel Cell Roars at Bronx Zoo.

The New York Power Authority (NYPA) plans to install a 200-kW fuel cell in the Wildlife Conservation Society’s “Madagascar!” exhibit at the Bronx Zoo, located inside the restored historic Lion House.  The 200-kW fuel cell will operate along with the existing on-site Bronx Zoo power facility and the Con Edison power grid.  The excess heat will be captured for heating the facility.

http://www.nypa.gov/press/2008/080619b.htm

MICRO FUEL CELLS

CMR Fuel Cells Signs MOU With Asian Manufacturer.

CMR Fuel Cells has signed a Memorandum of Understanding (MOU) with a leading Asian Original Design Manufacturer (ODM) agreeing to co-develop a fuel cell charger system for notebook computers. Under the terms of the agreement, the companies will collaborate in the design and development of a stand-alone, hybrid Direct Methanol Fuel Cell (DMFC) charger intended for consumer use.

http://www.cmrfuelcells.com/index.php?option=com_content&task=view&id=75&Itemid=4

Entrada de abril

Gracias a Dios que estamos en etapa de desarrollo del experimento. Por lo tanto se aceptan resultados raros y los errores que cometemos son tolerados. Al estar en esta etapa, ademas de que aprendemos muchisimo, surgen muchos problemas de “troubleshooting”. Una vez, un HPLC empezo’ a dar candela. Primero se tardaba mucho, luego se cambio’ la columna  lo cual requeria un cambio de temperatura y flujo, y despues empezo’ a chillar y la lectura no parecia concordar con la muestra. Dito y el graduado se habia amanecido haciendo standards… pobresito.  Entonces aparecio’ un aviso de una de las lamparas. Me quede’ fria, si una lampara de esas se danhaba costaria mucho $ y tiempo la reparacion. Llamamos a los proveedores del equipo nos comunicaron con un tecnico y al fin y al cabo el error se corrigio’ solo. :S

Hoy trabajabamos con un bioreactor y surgieron varias situaciones: no enroscaba bien el casco, no salia nada por la manga de salida del agua, formas de esterilizar el medidor de pH sin danharlo, etc. Pero cada miembro del equipo daba una sugerencia, probaba una idea, y asi fuimos resolviendo entre todos. Poco a poco le vamos conociendo las manhas al bioreactor bautizado “Frankestein”.

He observado que cuando todos los miembros del equipo estan listos para trabajar, aprender y buscar soluciones a imprevistos la experiencia es gratificante y uno puede apreciar lo ingeniosos que son los  miembros del equipo. En mi grupo de laboratorio siempre ha sido asi’ y estoy agradecida por eso.

Creo que este es mi ultimo “post” del semestre. Las entradas continuaran en agosto pero en verano estare’ en un internado de investigacion, asi que si me topo con algun articulo interesante lo dejare’ disponible aqui’.

Disfruten su verano.