02424naa a2200337 a 450000100080000000500110000800800410001902400400006010000210010024501940012126000090031552013090032465000160163365000180164965000250166765000260169265000160171865300190173465300220175365300160177565300210179165300290181265300210184170000230186270000220188570000220190770000210192970000230195070000280197377300850200118946142024-06-12       2011    bl uuuu     u00u1 u    #d7 a10.1016/j.ijhydene.2011.03.1192DOI1 aSÁ, L. R. V. de  aHydrogenase activity monitoring in the fermentative hydrogen production using heat pretreated sludgeba useful approach to evaluate bacterial communities performance.h[electronic resource]  c2011  aThe conversion of organic compounds into H2 has received increasing attention. Enrichment of inocula by heat pretreatment eliminates non-spore forming hydrogen consuming microorganisms and promotes spore germination in genus Clostridium, which is known as one of the key hydrogen producers. Useful information about metabolic pathway is provided by some intermediate metabolites, such as: acetic, propionic, butyric and formic acids. The increase of acetic/butyric acids ratio indicates H2 production in heat pretreated inoculum when compared to untreated inoculum in the same cultivation conditions. The effect of heat pretreatment on inocula and consequently on the performance of bacterial communities responsible for H2 production was monitored through the measurement of the level of hydrogenase gene expression, as well as through the content and distribution of volatile fatty acids. The acetic acid type fermentation was followed by the microorganisms presented in untreated and heat pretreated sludge. The medium containing untreated sludge presented a ratio of acetic/butyric acid of approximately 4, the same parameter was 7 when heat pretreated sludge was employed. The level of hydrogenase gene expression tripled when heat pretreated inoculum was used, indicating a higher production of H2.  abiohydrogen  amixed culture  avolatile fatty acids  aÁcido Graxo Volátil  aHidrogênio  aBiohidrogênio  aHeat pretreatment  aHidrogenase  aHydrogenase gene  aPré-tratamento de calor  aReal-time RT-PCR1 aOLIVEIRA, T. C. de1 aSANTOS, T. F. dos1 aSANTOS, A. M. dos1 aCAMMAROTA, M. C.1 aOLIVEIRA, E. M. M.1 aFERREIRA-LEITÃO, V. S.  tInternational Journal of Hydrogen Energygv. 36, n. 13, p. 7543-7549, Jul. 2011.