Data/hora: 11/06/2024 07:24:28

Provedor de dados: 	69	
País: 	Chile	
Título: 	Oxygen and temperature effect on continuous citric acid secretion in Candida oleophila	
Autores: 	Anastassiadis,Savas; Rehm,Hans-Jürgen.	
Data: 	2006-07-01	
Ano: 	2006	
Palavras-chave: 	Candida oleophila; Citric acid; Citric acid secretion.	
Resumo: 	The influence of air saturation and temperature on continuous citric acid secretion was studied in chemostat cultures of Candida oleophila ATCC 20177 (var.). Simultaneous measurements of intra- and extracellular concentration of glucose, citric and isocitric acid confirmed the involvement of a specific active transport system in citrate secretion, favouring citric acid over isocitrate. An optimum air oxygen saturation of 20% and temperature of 30-31&amp;ordm;C were determined for the continuous citric acid secretion. The highest values of citric acid concentration (98 g/L), citrate to isocitrate ratio (33.3:1), volumetric citric productivity (1.8 g/(L x h)), and specific citric acid productivity (0.1 g/(g x h)), were reached at 20% air saturation at a residence time of 54 hrs by the experiment's lowest biomass of 18 g/L. The highest isocitic acid volumetric productivity (55.6 mg/(L x h)) and specific productivity (0.99 mg/(g x h)) were identified at 50%, instead. The fastest citrate excretion rate of the generic product of 0.046 g/(g*h) was found at 30-31&amp;ordm;C. A concentration ratio between extra- and intracellular concentration of citrate of up to 9 was identified. The highest extra-/intracellular ratio of citrate and lowest intracellular concentrations of glucose, citric and isocitric acid were determined at optimum air saturation as a consequence of active citrate export.	
Tipo: 	Journal article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400010	
Editor: 	Pontificia Universidad Católica de Valparaíso	
Formato: 	text/html	
Fonte: 	Electronic Journal of Biotechnology  v.9 n.4 2006