title: Ethanol production efficiency of an anaerobic hemicellulolytic thermophilic bacterium, strain NTOU1, isolated from a marine shallow hydrothermal vent in Taiwan.
abstract: A new extremely thermophilic, anaerobic, gram-negative bacterium, strain NTOU1, was enriched and isolated from acidic marine hydrothermal fluids off Gueishandao island in Taiwan with 0.5% starch and 0.5% maltose as carbon sources. This strain was capable of growth utilizing various sugars found in lignocellulosic biomass as well as xylan and cellulose, and produced ethanol, lactate, acetate, and CO(2) as fermentation products. The results of a 16S rRNA gene sequence analysis (1,520 bp) revealed NTOU1 to belong to the genus Thermoanaerobacterium. When tested for the ability to grow and produce ethanol from xylose or rice straw hemicellulosic hydrolysate at 70°C, the strain showed the highest levels of ethanol production (1.65 mol ethanol mol xylose(-1)) in a medium containing 0.5% xylose plus 0.5% yeast extract. Maximum ethanol production from the rice straw hemicellulose was 0.509 g g(-1), equivalent to 98.8% theoretical conversion efficiency. Low concentrations of inhibitors (derived from dilute acid hydrolysis) in the rice straw hemicellulose hydrolysate did not affect the ethanol yield. Thus, Thermoanaerobacterium strain NTOU1 has the potential to be used for ethanol production from hemicellulose.
authors.affiliation: Institute of Marine Biology, National Taiwan Ocean University, Keelung, Taiwan.
authors.forename: Tsai-Ling
authors.initials: TL
authors.lastname: Tsai
authors.forename: Shiu-Mei
authors.initials: SM
authors.lastname: Liu
authors.forename: Shi-Chiang
authors.initials: SC
authors.lastname: Lee
authors.forename: Wei-Jei
authors.initials: WJ
authors.lastname: Chen
authors.forename: Sheng-Hsin
authors.initials: SH
authors.lastname: Chou
authors.forename: Tseng-Chieh
authors.initials: TC
authors.lastname: Hsu
authors.forename: Gia-Luen
authors.initials: GL
authors.lastname: Guo
authors.forename: Wen-Song
authors.initials: WS
authors.lastname: Hwang
authors.forename: Juergen
authors.initials: J
authors.lastname: Wiegel
mesh_terms: D000693:Anaerobiosis; D050260:Carbohydrate Metabolism; D016000:Cluster Analysis; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D000431:Ethanol / Q000378:metabolism*; D006358:Hot Temperature; D060086:Hydrothermal Vents / Q000382:microbiology*; D008969:Molecular Sequence Data; D012275:Oryza / Q000378:metabolism / Q000382:microbiology; D010802:Phylogeny; D018547:Plant Stems / Q000378:metabolism / Q000382:microbiology; D011134:Polysaccharides / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013624:Taiwan; D046950:Thermoanaerobacterium / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism* / Q000502:physiology
chemical_list: D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D011134:Polysaccharides; D012336:RNA, Ribosomal, 16S; D000431:Ethanol; C007916:hemicellulose