Thermophilic hydrogen production from cellulose with rumen fluid enrichment cultures: Effects of different heat treatments
✍ Scribed by Marika E. Nissilä; Hanne P. Tähti; Jukka A. Rintala; Jaakko A. Puhakka
- Book ID
- 103832883
- Publisher
- Elsevier Science
- Year
- 2011
- Tongue
- English
- Weight
- 553 KB
- Volume
- 36
- Category
- Article
- ISSN
- 0360-3199
No coin nor oath required. For personal study only.
✦ Synopsis
Elevated temperatures (52, 60 and 65 C) were used to enrich hydrogen producers on cellulose from cow rumen fluid. Methanogens were inhibited with two different heat treatments. Hydrogen production was considerable at 60 C with the highest H 2 yield of 0.44 mol-H 2 mol-hexose À1 (1.93 mol-H 2 mol-hexose-degraded À1 ) as obtained without heat treatment and with acetate and ethanol as the main fermentation products. H 2 production rates and yields were controlled by cellulose degradation that was at the highest 21%. The optimum temperature and pH for H 2 production of the rumen fluid enrichment culture were 62 C and 7.3, respectively. The enrichments at 52 and 60 C contained mainly bacteria from Clostridia family. At 52 C, the bacterial diversity was larger and was not affected by heat treatments. Bacterial diversity at 60 C remained similar between heat treatments, but decreased during enrichment. At 60 C, the dominant microorganism was Clostridium stercorarium subsp. leptospartum.