Journal of Biotechnology & Biomaterials
Open Access

Abstract

In recent years, much attention has been given to the potential of hydrogen production by fermentative pathways in waste water treatment processes. However, it is not a well-established technology and much investigation is still required. In this work, the effect of nutrients and yeast extract on biohydrogen production was evaluated by batch tests. Bottles of 250 ml useful volume containing 4.7 g/l of glucose (G), Glucose+Nutrients (GN), Glucose+Yeast extract (GY), and Glucose+Nutrients+Yeast extract (GNY) were incubated at 30 �°C for 7 days. Microbial growth was equivalent to (gVSS/l): G: 0.02, GN: 0.11, GY: 0.14 and GNY: 0.184. In order to obtain an inoculum concentration of 1.5 gVSS/l, specific volumes of each bottle (except G) were centrifuged and transferred to flasks of 15 ml useful volume, which were filled with the respective fresh solutions. In the first 30 hours, GNY achieved the faster hydrogen production (0.576 mmolH2/gVSS.h), followed by GY (0.184 mmolH2/gVSS.h) and GN (0.025 mmolH2/gVSS.h). However, the maximum H2 liquid yield, after 95 hours, was very close between GNY and GN, i.e., 1.80 and 1.47 molH2/molglucose, respectively, and much higher than that of GY, i.e., 0.85 molH2/molglucose. Regarding biogas composition, GNY exhibited the highest H2 content (58-73%), while GY and GN presented 50�±8 and 43�±19 H2% on average, respectively. These results indicate that yeast extract and nutrients had a synergic positive effect on biohydrogen production, as yeast extract contributed to the kinetics increase and the nutrients were essential to achieve the maximum hydrogen yield.

Biography

Vera Taina Mota is a PhD student in Sanitary Engineering from University of São Paulo, Brazil, and has BSc degree in Biology (specialization in Microbiology) and MSc in Environmental Engineering from Federal University of Minas Gerais, Brazil. She worked for public and private sectors in the field of sanitation and sewage services. She has published 4 papers in reputed journals, 11 conference presentations and 6 technical reports.

Email: vtaina@usp.br