초록
<P><B>Abstract</B></P> <P>The production of biohydrogen by psychrophilic G088 strain ([EU636029]), closely related to <I>Polaromonas rhizosphaerae</I> ([EF127651]) was evaluated using xylose, glucose, fructose, galactose, lactose or sucrose as a carbon source. Biohydrogen production was performed in 120 ml serological bottles with a production medium containing 2.75 g/l tryptone, 0.25 g/l yeast extract, and 20 g/l of each carbohydrate. Results showed that the G088 strain produced biohydrogen using all the evaluated substrates, ranging from 91.7 to 439.8 ml for lactose and glucose, respectively. However, glucose was the substrate with the highest consumption rate, accompanied by the maximum values of biohydrogen production rate and a biohydrogen yield of 50.1 ml/l/h and 1.7 mol H<SUB>2</SUB>/mol glucose, respectively. Analysis of the secreted metabolites showed that ethanol and organic acids were the main by-products. Our results demonstrate that the G088 strain has potential to be used for developing new biotechnological processes for biohydrogen production.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The psychrophilic G088 strain closely related to <I>Polaromonas rhizosphaerae</I> (EF127651) produce hydrogen at low temperatures. </LI> <LI> G088 strain is able to produce hydrogen using glucose, xylose, fructose, galactose, lactose and sucrose. </LI> <LI> The maximum hydrogen production, hydrogen production rate and hydrogen yield takes place using glucose as substrate. </LI> <LI> Hydrogen production parameters attained by G088 strain are comparable to those reported for mesophilic microorganisms. </LI> </UL> </P>