| 1. |
- Fazelinejad, Somayeh, et al.
(författare)
-
Fungal biomass and ethanol from lignocelluloses using Rhizopus pellets under simultaneous saccharification, filtration, and fermentation (SSFF)
- 2016
-
Ingår i: Biofuel Research Journal. - 2292-8782. ; 9, s. 372-378
-
Tidskriftsartikel (refereegranskat)abstract
- The economic viability of the 2nd generation bioethanol production process cannot rely on a single product but on a biorefinery built around it. In this work, ethanol and fungal biomass (animal feed) were produced from acid-pretreated wheat straw slurry under an innovative simultaneous saccharification, fermentation, and filtration (SSFF) strategy. A membrane unit separated the solids from the liquid and the latter was converted to biomass or to both biomassand ethanol in the fermentation reactor containing Rhizopus sp. pellets. Biomass yields of up to 0.34 g/g based on the consumed monomeric sugars and acetic acid were achieved. A surplus of glucose in the feed resulted in ethanol production and reduced the biomass yield, whereas limiting glucose concentrations resulted in higher consumption of xylose and acetic acid. The specific growth rate, in the range of 0.013-0.015/h, did not appear to be influenced by the composition of the carbon source. Under anaerobic conditions, an ethanol yield of 0.40 g/g was obtained. The present strategy benefits fromthe easier separation of the biomass from the medium and the fungus ability to assimilate carbon residuals in comparison with when yeast is used. More specifically, it allows in-situ separation of insoluble solids leading to the production of pure fungal biomass as a value-added product. (C) 2016 BRTeam. All rights reserved.
|
|
| 2. |
- FazeliNejad, Somayeh, et al.
(författare)
-
Inhibitor Tolerance : A Comparison between Rhizopus sp. and Saccharomyces cerevisiae
- 2013
-
Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 8:4, s. 5524-5535
-
Tidskriftsartikel (refereegranskat)abstract
- Zygomycetes fungi are able to produce ethanol, and their biomass may hold a high market value, making them interesting microorganisms from a biorefinery perspective. In the present study, the inhibitor tolerance of the Zygomycetes fungus Rhizopus sp. was evaluated and compared with a flocculating strain of Saccharomyces cerevisiae. The inhibitors furfural, 5-hydroxymethylfurfural [HMF], acetic acid, and levulinic acid and the phenolic compounds catechol, guaiacol, and vanillin were applied in different combinations in a semi-synthetic medium. Glucose uptake and conversion of HMF in the presence of inhibitors were analyzed for the two organisms, and it appeared that the inhibitor resistances of Rhizopus sp. and S. cerevisiae were comparable. However, in the presence of catechol (0.165 g L-1), guaiacol (0.186 g L-1), and vanillin (0.30 g L-1), the glucose uptake by S. cerevisiae was only 3.5% of its uptake in a medium without inhibitors, while under equal conditions, Rhizopus sp. maintained 43% of its uninhibited glucose uptake.
|
|
