초록
<P><B>Abstract</B></P> <P>One third of the World's entire food production is lost or wasted every year. Biohydrogen production offers a possibility to re-use this resource; in particular, bread and bakery products wastes, due to their composition (up to 70% of carbohydrates, mostly starch), represent an appropriate source of nutrients for microorganisms. The aim of this work was to convert bread wastes into hydrogen with a sequential system composed of lactic fermentation and photofermentation, with a minimum number of treatments to the substrate. The best results were provided by <I>Lactobacillus amylovorus</I> DSM 20532, followed by photofermentation by <I>Rhodopseudomonas palustris</I> 42OL, supplemented with ferric citrate and magnesium sulfate. The process led to 3.1 mol H<SUB>2</SUB> mol<SUP>−1</SUP> glucose, among the highest yields obtained on starch containing substrates, with an energy recovery of 54 MJ t<SUP>−1</SUP> dry waste. This study promotes the re-use of energy-containing food wastes for improving circular economy.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bread wastes are a suitable substrate for biohydrogen production. </LI> <LI> <I>Lactobaccillus amylovorus</I> efficiently converted starch into lactate in 18 h at 37 °C. </LI> <LI> No hydrolytic pretreatment on bread wastes was necessary. </LI> <LI> Fe(III) and MgSO<SUB>4</SUB> addition significantly improved hydrogen production. </LI> <LI> <I>Rhodopseudomonas palustris</I> produced 3.1 moL H<SUB>2</SUB> mol<SUP>−1</SUP> glucose. </LI> </UL> </P>