초록
<P><B>Abstract</B></P> <P>Bio-hydrogen, obtained by fermentation of organic residues, is considered a promising source of renewable energy. However, the industrial scale H<SUB>2</SUB> production from organic waste is far to be realized as technical and economical limitations have still to be solved. Low H<SUB>2</SUB> yields and lack of industrially robust microbes are the major limiting factors.</P> <P>To look for bacteria with both interesting hydrogen fermentative traits and proper robustness, granular sludge from a brewery full scale Upflow Anaerobic Sludge Blanket (UASB) digester was selected as trove of microbes processing complex substrates. One hundred and twenty bacterial strains, previously isolated from heat-treated granular sludge and genetically identified by 16S rDNA sequencing, were screened for extracellular hydrolytic enzymes on cellulose, hemicellulose, starch, pectin, lipids, protein. The most interesting hydrolytic strains were assessed for their H<SUB>2</SUB> production from glucose and soluble starch. Two <I>Bacillus</I> sp. strains, namely F2.5 and F2.8, exhibited high H<SUB>2</SUB> yields and were used as pure culture to convert Organic Fraction of Municipal Solid Waste (OFMSW) into hydrogen. The strains produced up to 61mL of H<SUB>2</SUB> per grams of volatile solids and could be considered as good candidates towards the development of industrially relevant H<SUB>2</SUB>-producing inoculants. This is the first successful application of pure microbial cultures in bio-hydrogen production from OFMSW.</P> <P><B>Highlights</B></P> <P> <UL> <LI> For the first time pure microbial cultures produced bio-hydrogen from organic waste. </LI> <LI> Two <I>Bacillus</I> sp. strains were selected for high amylolytic activities. </LI> <LI> The strains produced high H<SUB>2</SUB>-yields from glucose and soluble starch. </LI> <LI> Promising H<SUB>2</SUB> production was confirmed also from organic waste. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>