Search results for "Bioethanol"
showing 9 items of 9 documents
Aerobic catabolism and respiratory lactate bypass in Ndh-negative Zymomonas mobilis
2018
Ability to ferment in the presence of oxygen increases the robustness of bioprocesses and opens opportunity for novel industrial setups. The ethanologenic bacterium Zymomonas mobilis performs rapid and efficient anaerobic ethanol fermentation, yet its respiratory NADH dehydrogenase (Ndh)-deficient strain (ndh-) is known to produce ethanol with high yield also under oxic conditions. Compared to the wild type, it has a lower rate of oxygen consumption, and an increased expression of the respiratory lactate dehydrogenase (Ldh). Here we present a quantitative study of the product spectrum and carbon balance for aerobically growing ndh-. Ldh-deficient and Ldh-overexpressing ndh- strains were con…
Fragrant bioethanol: A valued bioproduct from orange juice and essential oil extraction
2018
Abstract We identify the composition of a less known, yet important bioproduct obtained in relatively high amount during orange fruit processing for juice and essential oil extraction comprised of bioethanol dissolving valued terpenes. Green cosmetic, perfume and biosolvent applications are anticipated.
Thermal transformation of micro-crystalline cellulose in phosphoric acid
2011
Use of crude oil derivatives such as diesel and gasoline is becoming unsuitable due to their detriment to environment and to the increasing worldwide energy demand which is driving crude oil reservoirs towards exhaustion. Replacement of diesel and gasoline with biofuels (i.e. biodiesel and bioethanol, respectively) is very desirable. In fact, biofuels are not only environmentally sustainable, but also potentially inexhaustible due to the large amounts of waste biomasses from which they can be retrieved. In the present study, a model compound (micro-crystalline cellulose) was dissolved in phosphoric acid and converted at 80 °C to glucose, thereby providing the possible substrate for fermenta…
Kondycjonowanie kukurydzy do produkcji bioetanolu
2016
Enzymatic Hydrolysis of Lignocellulose for Bioethanol Production
2017
Abstract The effect of temperature, time and amount of enzyme on hydrolysis of wheat straw lignocellulose remaining after furfural production was studied. The residual substrate was subjected to enzymatic hydrolysis at different temperatures — 45 °C, 50 °C and 55 °C. Hydrolysis time was 72 hours, and samples were taken every 24 hours. The maximum glucose yield (76.5% of the theoretically possible) was reached when hydrolysis temperature 50 °C was used. The production rate of glucose increased with a hydrolysis period of time. The yield of glucose significantly depended on the ratio of enzyme to substrate.
Sulla (Hedysarum coronarium L.) as Potential Feedstock for Biofuel and Protein
2016
Although sulla (Hedysarum coronarium L.) has many interesting features that could support the production of biofuels (e.g., a high yield and soluble sugar content, N-fixation capacity, low input requirements for its cultivation), no study has assessed the possibility of its use for that purpose. Our objective was to evaluate the potential value for energy production of sulla cut at various stages of growth. Furthermore, the potential of sulla as a dual purpose crop (energy and feed) was investigated. The crop was grown in rainfed conditions in a typical Mediterranean environment (over two complete 2-year crop cycles) and was cut at four different phenological stages. The biomass was divided…
Thermal degradation of microcrystalline cellulose in concentrated phosphoric acid
2011
The most common renewable fuel is ethanol. It is a liquid produced by fermentation of glucose which is very abundant in cellulose based materials. Bioethanol is achieved in a two-steps process: 1. hydrolysis of the cellulose included in the ligno-cellulosic materials to fermentable reducing sugars; 2. fermentation of such sugars to ethanol. While the second fermentation step, mediated by yeasts or bacteria, is very well established, the first one must be still assessed for process optimization. Many efforts have been made to identify solvents for cellulose in order to develop methods for the achievement of fermentable glucose. In the presence of mineral acid, cellulose undergoes hydrolysis …
Pretreatment of trace element-enriched biomasses grown on phytomanaged soils for bioethanol production
2017
Abstract Phytotechnologies are a set of sustainable, ecological options notably for alleviating pollutant linkages induced by contaminated soils. However, concerns exist regarding the processing of trace elements (TE)-enriched biomass and the fate of TEs in the end-products. The fractionation of phytoremediation TE-enriched non-woody lignocellulosic (tobacco) and woody (birch, willow) phytoremediation-borne biomasses was studied using ethanol organosolv, soda and dilute acid pretreatments. TE distribution in the process fractions (pulp, liquid effluents and lignin) was further examined. In dilute acid conditions, a wood pretreatment performed at 170 °C in the presence of 2% w/w of sulfuric …