Abstract
The conversion of raw starchy materials from sweet potato into ethanol in a mixed-culture of an amylolytic bacterium, Paenibacillus sp. and different strains of Zymomonas mobilis were studied. Raw starchy material from sweet potato was hydrolyzed by Paenibacillus sp. to glucose, which is directly used by Z. mobilis for ethanol production. A mixed-culture of Z. mobilis ATCC 29191 and Paenibacillus sp. 9 yielded the highest ethanol concentration (6.89 g/l) in cultures of small volumes. The effects of medium pH (the best pH value were between 5.0 and 6.0) and the supplementation of the medium with glucose on ethanol production were also studied. In a large-scale fermentation, the final concentration of ethanol was 6.60 g/l, which corresponds to 23.24% of the theoretical yield of the ethanol from 50.0 g/l of the starch from raw sweet potato after a 120 h fermentation period.
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Abate C.M., Castro G.R., Siñeriz F., Callieri D.A.S. (1999). Production of amylolytic enzymes byBacillus amylolique-faciens in pure culture and in co-culture withZymomonas mobilis. Biotechnol Lett., 21: 249–252.
Abouzied M., Reddy C. (1987). Fermentation of starch to ethanol by a complementary mixture of an amylolytic yeast andSaccharomyces cerevisiae. Biotechnol Lett., 9: 59–62.
Altintas M.M., Ulgen K.O., Kirdar B., Onsan Z., Oliver S.G. (2002). Improvement of ethanol production from starch by recombinant yeast through manipulation of environmental factors. Biotechnol. Bioeng., 31: 640–647.
Brestic-Goachet N., Gunasekaran P., Cami B., Baratti J. (1990). Transfer and expression of aBacillus licheniformis alpha-amylase gene inZymomonas mobilis. Arch Microbiol., 153: 219–225.
Budi S.W., Tuinen D. van., Arnould C., Dumas-Gaudot E., Gianinazzi-Pearson V., Gianinazzi S. (2000). Hydrolytic enzyme activity ofPaenibacillus sp. strain B2 and effects of the antagonistic bacterium on cell integrity of two soil-borne pathogenic fungi. Appl. Soil Ecol., 15: 191–199.
Chandel A.K., Chan E., Rudravaram R., Narasu L.M.L., Rao L.V., Ravindra P. (2007). Economics and environmental impact of bioethanol production technologies: an appraisal. Biotechnol. Mol. Biol. Rev., 2: 14–32.
Comis D. (2008). Agriculture Research Service USDA. Sweet potato out-yields corn in ethanol production study, http://www.ars.usda.gov/is/pr/2008/080820.htm>
Dostálek M., Häggström M. (1983). Mixed culture ofSaccharomycopsis fibuliger andZymomonas mobilis on starch-use of oxygen as a regulator. Eur. J. Appl. Microbiol. Biotechnol., 17: 269–274.
Goodman A.E., Rogers P.L., Skotnicki M.L. (1982). Minimal medium for isolation of auxotrophicZymomonas mutants. Appl. Environ. Microbiol., 44: 496–498.
Han I., Steinberg M.P. (1987). Amylolysis of raw cornAspergillus niger for simultaneous ethanol fermantation. Biotechnol. Bioeng., 30: 225–232.
Hoshino K., Tanikuchi M., Marumoto H., Fujii M. (1989). Repeated batch conversion of raw starch to ethanol using amylase immobilized on a reversible soluble-autoprecipitating carrier and flocculating yeast cells. Agric. Biol. Chem., 53: 1961–1967.
Hoshino K., Tanikuchi M., Marumoto H., Fujii M. (1990). Continuous ethanol production from raw starch using a reversibly soluble-autoprecipitating amylase and flocculating yeast cells. J. Ferment. Bioeng., 69: 228–233.
Huang J., Song J., Qiao F., Keith O.F. (2003). Sweet Potato in China: Economic Aspects and Utilization in Pig Production. International Potato Center (CIP), Bogor, Indonesia.
Kleerebezem R., Loosdrecht M.Cv. (2007). Mixed culture biotechnology for bioenergy production. Curr. Opin. Biotech., 18: 1–6.
Laluce C., Mattoon J.R. (1984). Development of rapidly fermenting strains ofSaccharomyces diastaticus for direct conversion of starch and dextrins to ethanol. Appl. Environ. Microbiol., 48: 17–25.
Miller G.L. (1959). Use of dinitrosalicylic acid reagent for determination of reducing sugar. Anal Chem., 31: 426–428.
Panesar P.S., Marwaha S.S., Kennedy J.F. (2006).Zymomonas mobilis: an alternative ethanol producer. J. Chem. Technol. Biotechnol., 81: 623–635.
Reddy O.V.S., Basappa S.C. (1996). Direct fermentation of cassava starch to ethanol by mixed cultures ofEndomycopsis fibuligera andZymomonas mobilis: Synergism and limitations. Biotechnol. Lett., 18: 1315–1318.
Rogers P.L., Jeon Y.J., Lee K.J., Lawford H.G. (2007).Zymomonas mobilis for fuel ethanol and higher value products. Adv. Biochem. Eng./Biotechnol., DOI 10.1007/10_2007_060.
Schwartz L (2008). China fuels ethanol industry with yams, sweet potatoes and cassava. http://www.renewableen-ergyworld.com/rea/news/story?id=52450.
Skotnicki M., Warr R., Goodman A., Lee K., Rogers P.L (1983), High productivity ethanol fermentation usingZymomonas mobilis. Biochem. Soc. Symp., 48: 53–86.
Swings J., Deley J. (1977). Biology ofZymomonas. Bacteriol. Rev., 41: 1–46.
Tanaka H.K., Murakami H. (1986). Ethanol production from starch by a coimmobilized mixed culture system ofAspergillus a wamori andZymomonas mobilis. Biotechnol. Bioeng., 28: 761–768.
Tanaka H., Ebata T., Kuwahara I., Matsuo M., Ogbonna J. C. (1999). Development and application of a system for analysis of mixed cultures of microorganisms. Appl. Biochem. Biotechnol., 80: 51–64.
Fang T.-Y., Ford C. (1998). Protein engineering ofAspergillus awamori glucoamylase to increase its pH optimum. Prot. Eng., 11: 383–388.
Verma G., Nigam P., Singh D., Chaudhary K. (2000). Bioconversion of starch to ethanol in a single-step process by coculture of amylolytic yeasts andSaccharomyces cerevisiae 21. Biores. Technol., 72: 261–266.
Yamade K., Fukushima S. (1989). Continuous alcohol production from starchy materials with a novel immobilized cell/enzyme bioreactor. J. Ferment. Bioeng., 67: 97–101.
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He, MX., Li, Y., Liu, X. et al. Ethanol production by mixed-cultures ofPaenibacillus sp. andZymomonas mobilis using the raw starchy material from sweet potato. Ann. Microbiol. 59, 749–754 (2009). https://doi.org/10.1007/BF03179219
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DOI: https://doi.org/10.1007/BF03179219