Kinetic modeling of simultaneous saccharification and fermentation of corn starch for ethanol production
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Fuel ethanol production, using a simultaneous saccharification and fermentation process (SSF) of native starch from corn flour, has been performed using Saccharomyces cerevisiae and a granular starch hydrolyzing enzyme. The quantitative effects of mash concentration, enzyme dose and pH were investigated with the use of a Box-Wilson central composite design protocol. Proceeding from results obtained in optimal fermentation conditions, a kinetics model relating the utilization rates of starch and glucose as well as the production rates of ethanol and biomass was tested. Moreover, scanning electron microscopy (SEM) was applied to investigate corn starch granule surface after the SFF process. A maximum ethanol concentration of 110.36 g/l was obtained for native corn starch using a mash concentration of 25%, which resulted in ethanol yield of 85.71%. The optimal conditions for the above yield were found with an enzyme dose of 2.05 ml/kg and pH of 5.0. These results indicate that by using a central composite design, it is possible to determine optimal values of the fermentation parameters for maximum ethanol production. The investigated kinetics model can be used to describe SSF process conducted with granular starch hydrolyzing enzymes. The SEM micrographs reveal randomly distributed holes on the surface of granules.
- Abouzied MM, Reddy CA (1987) Fermentation of starch to ethanol by a complementary mixture of an amylolytic yeast and Saccharomyces cerevisiae. Biotechnol Lett 9: 59-62.
- Davis RA (2008) Parameter estimation for simultaneous saccharification and fermentation of food waste into ethanol using matlab simulink. Appl Biochem Biotechnol 147: 11-27.
- Derringer G, Suich R (1980) Simultaneous optimization of several response variables. Journal of Quality Technology 12: 214-219.
- Haddad SA, Lindegren CC (1953) A Method for determining the weight of an individual yeast cell. Appl Microbiol 1: 153-156.
- Holm J, Björck I, Drews A (1986) A rapid method for the analysis of starch. Starch-Stärke 7: 224-226.
- Kobayashi F, Sawada T, Nakamura Y, Ohnaga M, Godliving M, Ushiyama T (1998) Saccharification and alcohol fermentation in starch solution of steam-exploded potato. Appl Biochem Biotechnol 69: 177-189.
- Kroumov AD, Módenes AN, de Araujo Tait MC (2006) Development of new unstructured model for simultaneous saccharification and fermentation of starch to ethanol by recombinant strain. Biochem Eng J 28: 243-255.
- Lee S (2007) Ethanol from corn. In Handbook of Alternative Fuel Technologies. Lee S, Speight JG, Loyalka SK, eds, pp 232-343. CRC Press, Boca Raton.
- Lim LH, Macdonald DG, Hill GA (2003) Hydrolysis of starch particles using immobilized barley α-amylase. Biochem Eng J 13: 53-62.
- Matsubara T, Ben Ammar Y, Anindyawati T, Yamamoto S, Ito K, Iizuka M, Minamiura N (2004) Degradation of raw starch granules by α-amylase purified from culture of Aspergillus awamori KT-11. Biochem Mol Biol 37: 422-428.
- Montesinos T, Navarro JM (2000) Production of alcohol from raw wheat flour by Amyloglucosidase and Saccharomyces cerevisiae. Enzyme Microb Technol 27: 362-370.
- Montgomery DC (2001) Design and analysis of experiments. 5th edn. John Wiley & Sons Inc; New Jersey.
- Montgomery DC, Runger GC (2003) Applied Statistics and Probability for Engineers. 3rd edn. John Wiley & Sons Inc, New Jersey.
- Morgan KR, Furneaux RH, Larsen NG (1995) Solid-state NMR studies on the structure of starch granules. Carbohydr Res 276: 387-399.
- Nichols NN, Dien BS, Bothast RJ, Cotta MA (2006) The Corn Ethanol Industry. In Alcoholic Fuels. Minteer S, ed, pp 59-79. CRC Press, Boca Raton.
- Öhgren K, Bura R, Lesnicki G, Saddler J, Zacchi G (2007) A comparison between simultaneous saccharification and fermentation and separate hydrolysis and fermentation using steam-pretreated corn stover. Process Biochem 42: 834-839.
- Öhgren K, Rudolf A, Galbe M, Zacchi G (2006) Fuel ethanol production from steam-pretreated corn stover using SSF at higher dry matter content. Biomass Bioenergy 30: 863-869.
- Oostergetel GT, van Bruggen EFJ (1993) The crystalline domains in potato starch granules are arranged in a helical fashion. Carbohydr Polym 21: 7-12.
- Philippidis GP, Smith TK (1995) Limiting factors in the simultaneous saccharification and fermentation process for conversion of cellulosic biomass to fuel ethanol. Appl Biochem Biotechnol 51/52: 117-124.
- Polakovic M, Bryjak J (2004) Modelling of potato starch saccharification by an Aspergillus niger glucoamylase. Biochem Eng 18: 57-63.
- Power RF (2003) Enzymatic conversion of starch to fermentable sugars. In. The Alcohol Textbook, fourth ed. Jacques KA, Lyons TP, Kelsall DR, eds, pp 23-32. Nottingham University Press, Nottingham.
- Robertson GH, Wong DW, Lee CC, Wagschal K, Smith MR, Orts WJ (2006) Native or Raw Starch Digestion: A Key Step in Energy Efficient Biorefining of Grain. J Agric Food Chem 54: 353-365.
- Senn T, Pieper HJ (2001) Part 1. Classical Methods. In The Biotechnology of Ethanol: Classical and Future Applications. Roehr M, ed, pp 1-87. WILEY-VCH Verlag GmbH, Weinheim.
- Suresh K, Kiran Sree N, Venkateswar Rao L (1999) Production of ethanol by raw starch hydrolysis and fermentation of damaged grains of wheat and sorghum. Bioprocess Eng 21: 165-168.
- Verma G, Nigam P, Singh D, Chaudhary K (2000) Bioconversion of starch to ethanol in a single-step process by coculture of amylolytic yeasts and Saccharomyces cerevisiae 21. Bioresour Technol 72: 261-266.
- Wang P, Singh V, Hue X, Johnston DB, Rausch KD, Tumbleson ME (2007) Comparison of raw starch hydrolyzing enzyme with conventional liquefaction and saccharification enzymes in dry-grind corn processing. Cereal Chem 84: 10-14.
- Ward C, Nolan AM, O'Hanlon K, McAree T, Barron N, McHale L, McHale AP (1995) Production of ethanol at 45°C on starch containing media by a mixed culture of thermotolerant, ethanol producing yeast Kluveromyces marxianus CBS 814.70 and a thermophilic filamentous fungus Taloromyces emersonii. Appl Microbiol Biotechnol 43: 408-411.
- Wyman CE (2003) Applications of corn stover and fiber. In Corn Chemistry and Technology, second ed. White PJ, Johnson LA, eds, pp 723-750. American Association of Cereal Chemists, St. Paul MN.
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