Fermentation of starch by Klebsiella oxytoca p2, containing plasmids with α‐amylase and pullulanase genes

• Autor(a) principal: Santos, Vera Lúcia dos
• Data de Publicação: 2000
• Outros Autores: Araújo, Elza Fernandes, Barros, Everaldo Gonçalves de, Guimarães, Walter Vieira
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://doi.org/10.1002/(SICI)1097-0290(19991220)65:6<673::AID-BIT8>3.0.CO;2-J; http://www.locus.ufv.br/handle/123456789/19753
• topic: Starch fermentation; Ethanol production; Klebsiella oxytoca

Klebsiella oxytoca P2(pC46), an ethanol‐producing recombinant, has been evaluated in fermentation of maltose and starch. The maximum ethanol produced by P2(pC46) was 0.34 g ethanol/g maltose and 0.38, 0.40, or 0.36 g ethanol/g starch in fermentation of 1, 2, or 4% starch, representing 68, 71, and 64% the theoretical yield. The pC46 plasmid transformed to cells of K. oxytoca P2 reduced the ethanol production from maltose and starch. In fermentation of starch after its digestion at 60°C for 24 h, in two‐step fermentation, the time for maximum ethanol production was reduced to 12–24 h and the theoretical yield was around 90%. The increase in starch concentration resulted in lower α‐amylase activity but in higher pullulanase activity. The high activity and thermostability of the amylolytic enzymes from this transformant suggest that it has a potential for amylolytic enzymes source.