Progress 10/29/09 to 10/28/14
Outputs
Progress Report Objectives (from AD-416): The overall objectives of this project are to develop economically viable technology to allow production of fuel ethanol from "Generation 1.5" regional non-corn feedstocks such as winter barley, that are grown outside the Corn Belt on fallow land or land that does not compete with food production. Evolve these ethanol plants into multiple product biorefineries, producing high value food and feeds and then into multi- feedstock biorefineries that can accept fermentable sugars from local lignocellulosic feedstock to produce additional ethanol and valuable coproducts. 1. In conjunction with CRADA partners and other collaborators, develop technologies that enable (1) commercially-preferred processes for converting winter barley into fuel ethanol in ways that significantly reduce biorefinery water usage and (2) commercially-viable, value-added co-products from barley-based biorefineries. 1a: Develop commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. 1b: Develop commercially-viable, value-added carbohydrate based co- products from barley kernels, hulls, and/or straw in barley-based biorefineries. 1c: Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. 2. In collaboration with NCAUR, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar- containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. Approach (from AD-416): In conjunction with CRADA partners and other collaborators, develop technologies that enable commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. Develop commercially-viable, value-added carbohydrate based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. In collaboration with NCAUR and other partners, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar-containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. The isolation, purification, characterization, structure/function relationship and applications of arabinoxylan (AX) and cellulose rich fraction (CRF) of barley hulls and straws were completed and the best technology with the cost information was transferred to Z-Trim Holdings, Inc. An aqueous enzymatic extraction method was developed to extract oil from wheat germ, barley germ, and rice bran. We then used several analytical methods to quantitatively analyze the components in these oils and to compare the compositions with oils extracted by conventional expelling and/or hexane extraction. An HPLC method previously reported to analyze alkylresorcinols in these oils was also found to be useful to analyze tocopherols and tocotrienols. The low moisture anhydrous ammonia (LMAA) process was used for pretreatment of barley straw, which eliminated the washing step required in the pretreatment using aqueous ammonia and resulted in tremendous savings of water consumption. The pretreated barley straw was hydrolyzed with commercial cellulase enzyme product and the hydrolysate was used as process water in the mashing of barley for ethanol production in a dry- grind simultaneous saccharification and fermentation (SSF) process. Ethanol production rates could be increased by using hydrolysate- acclimated yeast, resulting in significant reduction of total fermentation time. In addition, the glucose in the hydrolysate was fermented to produce additional ethanol. Barley hulls were pretreated by soaking in aqueous ammonia (SAA) and subsequently hydrolyzed with commercial cellulase (Accellerase 1000) plus commercial xylanase (Multifect Xylanase). Xylose isomerase (XI) was added to the hydrolysate to convert xylose to xylulose, which could be metabolized by the yeast Saccharomyces cerevisiae. The hydrolysate that was treated with XI was used as process water to prepare barley mash and fermented to produce ethanol. Control experiments in which de-ionized (DI) water and hydrolysate not treated with XI were used for barley mashing were also performed. The results indicated additional ethanol could be produced from the xylulose produced from xylose by the enzyme XI. However, the additional amount of ethanol produced was relatively small. The fermentations performed with the two hydrolysates also showed a lag period compared to the fermentation using DI water for mashing. It was concluded that the use of XI to increase ethanol yield was probably not commercially feasible.
Impacts
(N/A)
Publications
- Moreau, R.A., Hicks, K.B. 2013. Removal and isolation of germ-rich fractions from hull-less barley using a fitzpatrick comminuting mill. Cereal Chemistry. 90:546-551.
- Nghiem, N.P., Nguyen, C.M., Drapcho, C.M., Walker, T.H. 2013. Sweet sorghum biorefinery for production of fuel ethanol and value-added co- products. Biological Engineering Transactions (ASABE). 6(3):143-155.
- Nghiem, N.P., Kim, T., Yoo, C., Hicks, K.B. 2013. Enzymatic fractionation of SAA-pretreated barley straw for production of fuel ethanol and astaxanthin as a value-added co-product. Applied Biochemistry and Biotechnology. 171, Issue 2,p.341-351.
- Khatibi, P.A., Wilson, J., Berger, G., Brooks, W.S., Mcmaster, N., Griffey, C.A., Hicks, K.B., Nghiem, N.P., Schmale, D.G. 2014. A comparison of two milling strategies to reduce the mycotoxin deoxynivalenol in barley. Journal of Agricultural and Food Chemistry. 62(18):4204-4213.
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Progress 10/01/12 to 09/30/13
Outputs
Progress Report Objectives (from AD-416): The overall objectives of this project are to develop economically viable technology to allow production of fuel ethanol from "Generation 1.5" regional non-corn feedstocks such as winter barley, that are grown outside the Corn Belt on fallow land or land that does not compete with food production. Evolve these ethanol plants into multiple product biorefineries, producing high value food and feeds and then into multi- feedstock biorefineries that can accept fermentable sugars from local lignocellulosic feedstock to produce additional ethanol and valuable coproducts. 1. In conjunction with CRADA partners and other collaborators, develop technologies that enable (1) commercially-preferred processes for converting winter barley into fuel ethanol in ways that significantly reduce biorefinery water usage and (2) commercially-viable, value-added co-products from barley-based biorefineries. 1a: Develop commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. 1b: Develop commercially-viable, value-added carbohydrate based co- products from barley kernels, hulls, and/or straw in barley-based biorefineries. 1c: Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. 2. In collaboration with NCAUR, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar- containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. Approach (from AD-416): In conjunction with CRADA partners and other collaborators, develop technologies that enable commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. Develop commercially-viable, value-added carbohydrate based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. In collaboration with NCAUR and other partners, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar-containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. The arabinoxylan (AX) from barley straw was mixed with chitosan, homogenized using a high pressure homogenizer and mixture was used to make films. AX in combination with chitosan makes a good and stable film with antibacterial activity. The emulsion stability of AX from barley straw is superior to AX from barley hulls. Overall, all these AXs have good emulsion stabilizing capacity for an oil-in-water emulsion system. The emulsifying properties of AXs correlates well with their protein content except AX from barley hull, which has lower emulsifying properties even though it has high protein. The Cellulosic Rich Fraction (CRF) from both barley hulls and straw has high water holding capacity, which could be due to presence of arabinoxylan in the CRF. Developed a chromatographic method to fractionate tocopherols and other functional lipids from barley oil. We are now beginning to develop cost- effective molecular distillation methods to fractionate tocopherols and other functional lipids from barley oil. Molecular distillation methods could be scaled up and used to process large amounts of barley oil. Developed an aqueous enzymatic oil extraction process to extract barley oil from barley germ and wheat germ which achieves oil yields of about 60%. Research is continuing to improve oil yields and to reduce the cost of the process. Barley straw and barley hulls pretreated by dilute acid and alkaline hydrogen peroxide processes developed at the National Center for Agricultural Utilization Research (NCAUR) were hydrolyzed by ACCELLERASE 1500 and ACCELLERASE XY. The effects of enzyme dosages were investigated. Hydrolysates obtained from barley straw and barley hulls pretreated by dilute acid were highly toxic to commercial yeast. Theoretically these hydrolysates can be detoxified prior to fermentation. However, the detoxification process may be too expensive and make production of ethanol using these feedstocks uneconomical. Decision on whether detoxification will be attempted will be made. Preferred conditions for enzymatic hydrolysis of barley straw and barley hulls that had been pretreated with a soaking in aqueous ammonia (SAA) process were established. Experiments on using the hydrolysates as mashing water for ethanol production from dehulled barley (endosperm) are in progress. We worked with a team at Virginia Tech to develop a process to remove toxic mycotoxins from Fusarium-infected, field-grown hulled barley so it can be used for fuel and feed purposes. The hypothesis tested was that removal of the hull from the barley kernel would also remove most of the mycotoxins from the barley. Two different hull removal processes were used including roller milling followed by sieving and a �precision� dehulling process previously developed by us. The precision milling was far more effective than the roller milling at removing mycotoxins from hulled barley, removing the hull and up to 85% of the mycotoxins without significant loss of important kernel components such as starch and protein. This work has been described in a manuscript that has been submitted to a peer reviewed journal. Accomplishments 01 Winter Barley for advanced biofuels. Before 2013, barley was not approved by the Environmental Protection Agency as an official feedstock for U.S. biofuels production under the Renewable Fuel Standard statute. Over the last 5 years, ARS researchers at Wyndmoor, Pennsylvania collaborated with international enzyme companies, plant breeders, entrepreneurs, life-cycle experts, and ethanol plant designers to develop new winter barley varieties, new efficient processes to convert barley into fuel ethanol and to conduct critical analyses on the economics and the environmental benefits of barley ethanol. In response to these accomplishments and the information they contained, the Environmental Protection Agency proposed barley as an acceptable feedstock for renewable fuels and also proposed it as a feedstock for making environmentally preferred �Advanced� biofuels when produced using certain manufacturing processes developed by the team. Because of the important research conducted by ARS and its collaborators and because of the decision by EPA, ethanol plants in the US will soon be able to use barley to make conventional and advanced fuel ethanol and, in the latter case, can receive an economic incentive for using barley over other conventional feedstocks such as corn. Use of winter barley will reduce usage of corn for biofuel production and will lessen stress on food and feed markets for corn. It will also provide economic benefits for farmers and agriculture outside the Corn Belt.
Impacts
(N/A)
Publications
- Yoo, C., Nghiem, N.P., Hicks, K.B., Kim, T. 2013. Maximum production of fermentable sugars from barley straw using optimized soaking in aqueous ammonia (SAA) pretreatment. Applied Biochemistry and Biotechnology. 169(8) :2430-2441.
- Brooks, W.S., Berger, G.L., Griffey, C.A., Thomason, W.E., Paling, J.J., Hokanson, E.G., Behl, H.D., Liu, S.Y., Gundrum, P.G., Price, A.M., Brann, D.E., Vaughn, M.E., Pitman, R.M., Dunaway, D.W., Corbin, R.A., Kenner, J.C. , Beahm, B.R., Whitt, D.L., Custis, J.T., Starner, D.E., Gulick, S.A., Ashburn, S.R., Jones, E.H., Marshall, D.S., Fountain, M.O., Tuong, T.D., Livingston, D.P., Premakumar, R., Kurantz, M.J., Taylor, F., Moreau, R.A., Hicks, K.B. 2013. Registration of 'Eve' winter hulless barley. Journal of Plant Registrations. 7:5-11.
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Progress 10/01/11 to 09/30/12
Outputs
Progress Report Objectives (from AD-416): The overall objectives of this project are to develop economically viable technology to allow production of fuel ethanol from "Generation 1.5" regional non-corn feedstocks such as winter barley, that are grown outside the Corn Belt on fallow land or land that does not compete with food production. Evolve these ethanol plants into multiple product biorefineries, producing high value food and feeds and then into multi- feedstock biorefineries that can accept fermentable sugars from local lignocellulosic feedstock to produce additional ethanol and valuable coproducts. 1. In conjunction with CRADA partners and other collaborators, develop technologies that enable (1) commercially-preferred processes for converting winter barley into fuel ethanol in ways that significantly reduce biorefinery water usage and (2) commercially-viable, value-added co-products from barley-based biorefineries. 1a: Develop commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. 1b: Develop commercially-viable, value-added carbohydrate based co- products from barley kernels, hulls, and/or straw in barley-based biorefineries. 1c: Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. 2. In collaboration with NCAUR, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar- containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. Approach (from AD-416): In conjunction with CRADA partners and other collaborators, develop technologies that enable commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. Develop commercially-viable, value-added carbohydrate based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. In collaboration with NCAUR and other partners, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar-containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. Developed a high-solid fermentation process for barley ethanol production. This process uses the native enzymes that are present in the barley grains during a short incubation period (2 hours) at low temperature (60oC) to reduce the viscosity of the mash and allow use of high solid concentrations. We were able to use 35% solids (dry basis) and achieve almost 19% ethanol by volume (150 g/liter). All of these results were transferred to our CRADA partner. Cellulose-rich residues obtained by AHP extraction of barley straw and barley hulls were subjected to fed-batch simultaneous saccharification and fermentation (SSF) using the yeast Saccharomyces cerevisiae. Final ethanol concentrations of ~50 g/l were obtained. We also developed a process for obtaining fermentable sugars from barley hull and integration of these sugars in a barley biorefinery for production of ethanol by yeast (from glucose) and value-added co-products such as astaxanthin (from other sugars such as xylose). In collaboration with Iowa State University (ISU) optimum conditions of Soaking in Aqueous Ammonia (SAA) pretreatment of barley straw were determined. Pretreated barley straw was fractionated by commercial xylanase hydrolysis. The xylose-rich solutions were used for astaxanthin fermentation. The cellulose-rich residue was subjected to fed-batch SSF fermentation using the yeast Saccharomyces cerevisiae to obtain final ethanol concentrations above 70 g/l. Worked to develop a procedure to isolate water soluble arabinoxylan (A)X and water insoluble CRF fractions from barley hulls and straws by simple and economical steam treatment without using any acid or base. The yield of AX was lower than obtained by standard hydrogen peroxide technology used previously in our laboratory. Water binding properties of cellulosic residue fraction (CRF) and the emulsion stability studies of AX have been completed. CRF from both barley hulls and straws have high water holding capacity. The emulsion stabilities of AX from barley straws are superior to AX from barley hulls. Overall, all these AXs have good emulsion stabilizing capacity for oil- in-water emulsion system. Considerable research was conducted to identify functional lipid co- products in barley hulls and milling fractions, and initial research was conducted on identifying these compounds in barley straw. Accomplishments 01 Integrated process for production of fuel ethanol and value-added co- products from barley straw. Making fuel ethanol from non-food feedstocks like barley straw is a good idea since use of this feedstock doesn�t deplete food and feed supplies. Unfortunately, the present processes fo making fuel ethanol from barley straw are too expensive to be commercialized. Therefore, ARS researchers at Wyndmoor, Pennsylvania developed a set of integrated processes to solve this problem by doing several simultaneous things: First, use of simple ammonia treatment was shown to make the barley straw more easily converted to fuel ethanol. Second, a new fermentation process was developed that made ethanol in mu higher concentrations than previous processes, making the ethanol cheape to distill. Third, the leftovers from the fermentation were �fed� to another microorganism, which ate them and produced a very valuable coproduct, an ingredient called �astaxanthin� used in aquaculture feeds. Use of all these new technologies together will make cellulosic ethanol from barley straw more profitable for the producer and more economical f the user. These results are being transferred to commercial partners wh will share them with many companies trying to make cellulosic ethanol. 02 New barley varieties are low in troublesome �phytate� but not in other k nutrients. Phytate is a natural form of phosphorous found in barley kernels that is difficult for animals to digest. Animals fed barley die excrete this phytate in their manure and the phytate results in pollutio of streams and waterways. ARS and other breeders have now produced low- phytate barley cultivars which lessen this pollution problem. However, normal barley cultivars also contain nutrients and health-promoting compounds like cholesterol-lowering phytosterols, vitamin E, and beta- glucans which are important for the health and wellness of the animals a humans who consume barley. It was therefore necessary to show that low phytate barleys did not also contain lower levels of these important nutrients. ARS researchers at Wyndmoor, Pennsylvania and Aberdeen, Idah analyzed both normal and low-phytate barleys and found that except for differences in the levels of phytate, other health-promoting nutrients were present in normal quantities in the low phytate barleys. Now growe feeders, and grain processers can use low phytate barleys and be assure that the recipients of these grains will not be short changed on nutriti 03 New method precisely removes hulls from barley without removing barley kernel nutrients. ARS researchers at Wyndmoor, Pennsylvnia developed a new milling method to precisely remove the low-value barley hull from barley kernels without removing valuable starch, protein, and vitamins from the kernel. The method uses a commercial milling device used in a new way to produce de-hulled barley kernels that are useful as feedstock for fuel ethanol production as well as superior as feed for monogastric animals. The method was given a Superior Paper Award by the American Society of Agricultural and Biological Engineers. 04 New method helps assure that food products labeled �made with whole grai actually contain that health-promoting ingredient. Alkylresorcinols are natural molecules that occur in whole grains from wheat, barley, and oth cereals and are now being used as �biomarkers� to identify foods that ar prepared from whole grains. The existing method to measure the amount o alkylresorcinols in foods is slow and tedious. ARS researchers at Wyndmoor, Pennsylvania developed a new, automated, and fast method to measure alkylresorcinols in food products containing cooked and uncooked cereals. This work was published in 2012 in the Journal of Agriculture and Food Chemistry and will be useful for all who conduct research on these important biomarkers and will help to ensure the authenticity of whole grain food products.
Impacts
(N/A)
Publications
- Holt, M.D., Moreau, R.A., Dermarderosian, A., Mckeown, N., Jacques, P.F. 2012. Accelerated solvent extraction of alkylresorcinols in food products containing uncooked and cooked wheat. Journal of Agricultural and Food Chemistry. 60:4799-4802.
- Moreau, R.A., Nghiem, N.P., Rosentrater, K.A., Johnston, D., Hicks, K.B. 2012. Ethanol production from starch-rich crops other than corn and the composition and value of the resulting DDGS. In: Liu, K., Rosentrater, K.A. , editors. Distillers Grains: Production, Properties and Utilization. Boca Raton, FL: CRC Press. p. 103-117.
- Hicks, K.B., Wilson, J., Flores, R.A. 2011. Progressive hull removal from barley using the Fitzpatrick comminuting mill. Applied Engineering in Agriculture. 27(5):797-802.
- Nghiem, N.P., Taylor, F., Hicks, K.B., Johnston, D., Shetty, J. 2011. Scale-up of ethanol production from winter barley by the EDGE (enhanced dry grind enzymatic) process in fermentors up to 300 liters. Applied Biochemistry and Biotechnology. 165:870-882.
- Srinivasan, R., Hicks, K.B., Wilson, J., Challa, R.K. 2012. Effect of barley roller milling on fractionation of flour using sieving and air classification. Applied Engineering in Agriculture. 28(2):225-230.
- Moreau, R.A., Bregitzer, P.P., Liu, K., Hicks, K.B. 2012. Compositional equivalence of barleys differing only in low and normal phytate levels. Journal of Agricultural and Food Chemistry. 60:6493-6498.
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Progress 10/01/10 to 09/30/11
Outputs
Progress Report Objectives (from AD-416) The overall objectives of this project are to develop economically viable technology to allow production of fuel ethanol from "Generation 1.5" regional non-corn feedstocks such as winter barley, that are grown outside the Corn Belt on fallow land or land that does not compete with food production. Evolve these ethanol plants into multiple product biorefineries, producing high value food and feeds and then into multi- feedstock biorefineries that can accept fermentable sugars from local lignocellulosic feedstock to produce additional ethanol and valuable coproducts. 1. In conjunction with CRADA partners and other collaborators, develop technologies that enable (1) commercially-preferred processes for converting winter barley into fuel ethanol in ways that significantly reduce biorefinery water usage and (2) commercially-viable, value-added co-products from barley-based biorefineries. 1a: Develop commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. 1b: Develop commercially-viable, value-added carbohydrate based co- products from barley kernels, hulls, and/or straw in barley-based biorefineries. 1c: Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. 2. In collaboration with NCAUR, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar- containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. Approach (from AD-416) In conjunction with CRADA partners and other collaborators, develop technologies that enable commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. Develop commercially-viable, value-added carbohydrate based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. In collaboration with NCAUR and other partners, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar-containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. Sub-Objective 1a: Developed a high-solid fermentation process for barley ethanol production. This process uses the native enzymes that are present in the barley grains during a short incubation period (2 hours) at low temperature (60oC) to reduce the viscosity of the mash and allow use of high solid concentrations. We were able to use 35% solids (dry basis) and achieve almost 19% ethanol by volume (150 g/liter). Used our new precision barley de-hulling process and a roller milling process as a way to potentially remove mycotoxins like deoxynivalenol (DON) from barley kernels prior to making fuel ethanol. If this is effective, it will result in improved DDGS that contain low enough levels of toxins to be fed to animals rather than being land filled or incinerated. Sub-Objective 1b: Determined the sugar composition of arabinoxylan (AX) and cellulose rich fractions (CRF) from barley hull and straw to determine their structure, composition and potential new uses. Water binding studies of CRFs indicated that they have very high water holding capacity useful for the food industry. Sub-Objective 1c: Developed a process to isolate a very pure germ fraction from hull-less barley using a comminuting mill. The goal was to produce fractions of barley that are enriched in health-promoting tocotrienols and other phytonutrients. This barley germ fraction contains up to 16% hexane extractable oil, which is higher than the amount of oil in barley germ obtained by hand dissections and higher than the amount of oil in commercial wheat germ. Objective 2: Developed a process for obtaining fermentable sugars from barley hull and integration of these sugars in a barley biorefinery for production of ethanol by yeast (from glucose) and value-added co-products such as astaxanthin (from other sugars such as xylose). Also, in experiments with Iowa State University a new and highly effective Low Moisture Aqueous Ammonia (LMAA) process was developed for pre-treating cellulosic biomass before cellulosic ethanol production. The process appears to have advantages over the state of the art. An invention report and a manuscript were written Accomplishments 01 New process to simultaneously make cellulosic and starch ethanol from barley. ARS researchers at Wyndmoor, PA, collaborated with researchers Iowa State University to develop a new process to simultaneously generat fermentable sugars from starch and cellulose that are present in hulled barley kernels. The process does not require any grinding or removal of the barley hull that is used in conventional processes to convert barley to sugars and fuel ethanol. Instead, the whole barley kernel is subject to cooking at low pH and moderate pressures before being exposed to commercial enzymes that break down both starch and cellulose simultaneously into sugars that can be fermented by brewer�s yeast into fuel ethanol. The result is the first process to make fermentable sugars from both cellulose and starch in the same process from barley and the process can be extended to corn, sorghum, triticale and rye. Use of thi published and patent pending process will allow the production of more ethanol per bushel of grain feedstock and may also result in ethanol wit low enough lifecycle green house gas emissions (relative to gasoline), t qualify as an advanced biofuel as defined by the Environmental Protectio Agency. 02 Completing an economic analysis of a new barley fuel ethanol process. AR researchers at Wyndmoor, PA, compared the cost of making fuel ethanol fr barley in a conventional process to the cost of using a new ARS �EDGE� (enhanced dry grind enzymatic) process that uses a special enzyme to eas processing and increase ethanol yields. To do the comparison, the researchers built a techno-economic computer model that simulated the conventional barley to ethanol process then they modified the model to represent the new EDGE process. When the models were compared, it was found that if barley prices were less than about $2.00 per bushel, the EDGE process was not economic. However, with barley prices at the curre level of $4-$6 per bushel and with present costs of the enzyme, the EDGE process results in significant savings over the conventional process. Companies using barley to produce fuel ethanol in North America and Euro can use this recently published information to determine which process they will use in their facilities. 03 New process to remove mycotoxins from barley grain while simultaneously making fuel ethanol. Barley grown in seasons with high rainfall is sometimes contaminated with toxins produced by fungi that grow in the field on the moist barley kernels. These �mycotoxins� are toxic to huma and animals and thus barley grain contaminated with them cannot be used for food or feed. ARS researchers at Wyndmoor, PA, collaborated with researchers at Virginia Tech to develop a new yeast strain and showed th it can convert barley to fuel ethanol and simultaneously convert the mycotoxin called deoxynivalenol (DON) into less toxic forms so that the resulting ethanol coproduct, distiller�s dried grains with solubles (DDG can be fed to animals. This is the first work of its kind and it has potential to allow use of contaminated barley in fuel and feed markets which will help farmers and ethanol producers avoid crop and product losses. The work has been published and covered in numerous press releas around the world.
Impacts
(N/A)
Publications
- Kim, T., Nghiem, N.P., Taylor, F., Hicks, K.B. 2011. Consolidated conversion of hulled barley into fermentable sugars using chemical, thermal, and enzymatic (C.T.E.) treatment. Applied Biochemistry and Biotechnology. 164:534-545.
- Nghiem, N.P., Ramirez, E., Mcaloon, A.J., Yee, W.C., Johnston, Hicks, K.B. 2011. Economic analysis of fuel ethanol production from winter hulled barley by the EDGE (Enhanced Dry Grind Enzymatic) process. Bioresource Technology. 102:6696-6701.
- Doehlert, D.C., Moreau, R.A., Welti, R., Roth, M.R., Mcmullen, M.S. 2010. Polar lipids from oat kernels. Cereal Chemistry. 87(5):467-474.
- Griffey, C., Brooks, W., Vaughn, M., Thomason, W., Paling, J., Pitman, R., Dunaway, D., Corbin, R., Kenner, J., Hokanson, E., Behl, H., Beahm, B., Liu, S., Gundrum, P., Brann, D., Whitt, D., Custis, J., Starner, D., Gulick, S., Ashburn, S., Jones, N., Marshall, D.S., Fountain, M.O., Tuong, T.D., Premakumar, R., Livingston, D.P., Hicks, K.B., Kurantz, M.J., Taylor, F., Moreau, R.A. 2011. Registration of 'Dan' winter hulless barley. Journal of Plant Registrations. 5:1-4.
- Khatibi, P.A., Montanti, J.M., Nghiem, N.P., Hicks, K.B., Berger, G., Brooks, W.S., Griffey, C.A., Schmale, D.G. 2011. Conversion of deoxynivalenol to 3-acetyldeoxynivlenol in barley derived fuel ethanol co- products with yeast expressing trichothecene 3-0-acetyltransferases. Biotechnology for Biofuels. 4:26. DOI: 10.1186/1754-6834-4-26.
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Progress 10/01/09 to 09/30/10
Outputs
Progress Report Objectives (from AD-416) The overall objectives of this project are to develop economically viable technology to allow production of fuel ethanol from "Generation 1.5" regional non-corn feedstocks such as winter barley, that are grown outside the Corn Belt on fallow land or land that does not compete with food production. Evolve these ethanol plants into multiple product biorefineries, producing high value food and feeds and then into multi- feedstock biorefineries that can accept fermentable sugars from local lignocellulosic feedstock to produce additional ethanol and valuable coproducts. 1. In conjunction with CRADA partners and other collaborators, develop technologies that enable (1) commercially-preferred processes for converting winter barley into fuel ethanol in ways that significantly reduce biorefinery water usage and (2) commercially-viable, value-added co-products from barley-based biorefineries. 1a: Develop commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. 1b: Develop commercially-viable, value-added carbohydrate based co- products from barley kernels, hulls, and/or straw in barley-based biorefineries. 1c: Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. 2. In collaboration with NCAUR, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar- containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. Approach (from AD-416) In conjunction with CRADA partners and other collaborators, develop technologies that enable commercially-preferred processes for converting winter barley into fuel ethanol and improved DDGS in ways that increase ethanol yield and significantly reduce biorefinery water usage. Develop commercially-viable, value-added carbohydrate based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. Develop commercially-viable, value-added lipid based co-products from barley kernels, hulls, and/or straw in barley-based biorefineries. In collaboration with NCAUR and other partners, develop technologies that enable the commercially-preferred conversion of barley hulls and/or straw into sugar-containing make-up water, allowing the production of ethanol from both starch and cellulose in a barley grain-based biorefinery. We worked with our CRADA partner to conduct research to support the new Appomattox Bio Energy Barley ethanol plant being built in Hopewell Virginia. Our work focused on improving our previously developed barley EDGE ethanol process so that it is optimized for a 60 million gallon per year commercial plant. To do this, several modifications must be made to our lab/pilot scale process. One aspect we focused on was to develop a pre-incubation process that would optimize use of enzymes and lead to higher ethanol yields. Preliminary studies show that of the 5 classes of enzymes being used in the process, one enzyme, beta-glucosidase, is critical for producing the highest ethanol yields. It was found that use of a pre-incubation stage for the barley mash before the liquefaction step may result in lower cost and higher yields. Progress was made on the extraction of all constituents including arabinoxylan and cellulose rich fractions from several varieties of barley hulls and straws from different sources. Organic solvent-soluble components of barley hulls and straws obtained were dried and their percentage yields calculated. The water soluble components, starch, Hemi. A, Hemi. B (arabinoxylan), oligosaccharides, acid insoluble lignin, acid soluble lignin and cellulosic residue from all these barley hulls and straws were also extracted, dried and their percent yields were calculated. As part of our effort to identify and quantify co-products in barley and in barley processing fractions, ten new barley cultivars were obtained from ARS barley breeders in Aberdeen, Idaho. One of these, Clearwater, is an important new cultivar developed to have enhanced feed value, because it contains very low levels of phytate. Kernel samples were extracted and quantitatively analyzed for total oil, the four common barley tocopherols and the four common barley tocotrienols. One cultivar was found to contain about 30% more oil than the others. We previously reported that barley oil contains the higher levels of health- promoting tocotrienols than any other common seed oil. As with older barley cultivars, the barley oil from these ten new cultivars contained consistently high levels of tocotrienols. We are collaborating with engineers at Iowa State University with experience in cellulosic ethanol pretreatment, saccharification, and fermentation to migrate cellulosic ethanol technology into barley (starch) ethanol plants. Biomass feedstocks including corn stover and barley hull were treated with the Iowa State SAA cellulosic ethanol pretreatment technology. The treated materials were first hydrolyzed with Multifect Xylanase to generate a xylose-rich stream. The residual sold is then hydrolyzed with Accellerase cellulase to generate a glucose-rich stream. Thus the two main carbohydrate fractions of the biomass were fractionated into two separate fermentable sugar solutions, which could be used with suitable microorganisms for production of value-added co-products and ethanol. Accomplishments 01 Two-Phase Simultaneous Saccharification and Fermentation (TPSSF) process improves yield of ethanol from corn stover. The production of bioethan from lignocellulosic feedstock is much more difficult than starch-based ethanol production for several reasons. For one, lignocellulose contain both hexoses, such as glucose, and also pentoses, such as xylose. Brewe yeast can easily convert glucose to ethanol but cannot convert pentoses, such as xylose into ethanol. Commercial bioconversion of lignocellulose ethanol requires efficient fermentation of all the sugars. If this cann be achieved, the ethanol yield will be too low to make the lignocellulos ethanol cost-competitive. Currently, researchers are trying to develop n microorganisms that can convert both hexoses and pentoses to ethanol simultaneously. One of the major problems with these recombinant organisms is they ferment glucose preferentially and do not begin to metabolize xylose until low glucose concentrations have been reached. Th results in very long fermentations times and incomplete conversion of xylose in mixed sugar solutions obtained from lignocellulosic biomass. T overcome this hurdle, ARS researchers have developed a Two-Phase Simultaneous Saccharification and Fermentation (TPSSF) process in which xylose is preferentially released from a pretreated biomass and simultaneously fermented to ethanol first using an organism capable of highly efficient xylose metabolism, followed by release of glucose and i simultaneous conversion to ethanol by the yeast Saccharomyces cerevisiae which has been known for high ethanol yields. We used this new process o corn stover. The results were outstanding as an ethanol yield of 84% of theoretical value was achieved with E coli KO11 (a xylose-fermenting bacterium) and subsequently with S cerevisiae D5A (a glucose-fermenting yeast). This high level of sugar conversion will be of value in improvin the economics of lignocellulosic ethanol production.
Impacts
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Publications
- Li, X., Kim, T., Nghiem, N.P. 2010. Bioethanol production from corn stover using aqueous ammonia pretreatment and two-phase simultaneouos saccharification and fermentation (TPSSF). Bioresource Technology. 101:5910-5916.
- Griffey, C., Brooks, W., Kurantz, M.J., Thomason, W., Taylor, F., Obert, D. E., Moreau, R.A., Flores, R., Sohn, M., Hicks, K.B. 2010. Grain composition of Virginia winter barley and implications for use in feed, food, and biofuels production. Journal of Cereal Science. 51:41-49.
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