976 research outputs found
Environmentally sustainable processes for biomass conversion into biofuels and value-added compounds: integrated and intensified approach within a biorefinery concept
Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Lignocellulosic biomass conversion into biofuels is considered a promising alternative to replace fossil fuels, being one of investment priorities of European Union to attain a sustainable growth within Horizon 2020. Nevertheless, lignocellulosic biofuels are not widely implemented on large-scale due to the high initial investment and operational costs. The scientific research carried out has been focused in the development of biomass processing technology for bioethanol production making use of environmentally-friendly pre-treatments and molecular biotechnology tools (metabolic, genetic and physiological engineering) for yeast development. [...]info:eu-repo/semantics/publishedVersio
Bioethanol production from vine pruning residue by sequential steps of autohydrolysis
Lignocellulosic biomass is a renewable raw material, widespread and with a huge potential for
the manufacture of biofuels as bioethanol. In Portugal, the most abundant exploitable
lignocellulosic biomass derives from the agro-industrial and forestry sectors. Large amounts of
residues are generated during wine processing, specially pruning residues of vine. Approximately
1.2-3.5 t/ha of vine pruning residues (VPR) are estimated to be produced per year, which are
usually burnt in the field. VPR are composed by 30.6 % of cellulose, 18.2 % of hemicellulose and
29.5 % of lignin. In order to produce ethanol from this agro-industrial residue, autohydrolysis
treatment in two sequential steps were proposed for solubilization of hemicellulose in a separate
stream and improving the enzymatic susceptibility of cellulose following the biorefinery concept.
In a first stage, VPR was submitted to autohydrolysis treatment at 180 ÂșC for 60 min (Severity
factor, So=4.13) at liquid to solid ratio = 6 g of distilled water/g of VPR. In liquid phase, 55 g of
xylan/100 g of xylan in raw material was recovered as xylooligosaccharides (13 g/L).
Autohydrolyzed VPR was evaluated in a second step of autohydrolysis treatment under
temperature in the range 180- 200 ÂșC and time 30-40 min. After sequential treatments, 90-99 %
of cellulose was recovered in solid phase and enzymatic saccharification of pretreated solid was
assayed using 25 FPU/g of cellulase CTec2 and solid loading of 5 and 10 % of pretreated VPR.
Sequential treatment of VPR significantly improved the enzymatic hydrolysis of cellulose from 70
% to 100 % of cellulose to glucose conversion for second autohydrolysis at 200 ÂșC for 30 min.
Under these conditions of pretreatment, two configurations of saccharification and fermentation
(simultaneously âSSF- and separately âSHF-) were carried out. Ethanol production was successfully
obtained from two processes achieving cellulose to ethanol conversion of 93 and 97 % for SHF and
SSF, respectively
Polyphenols and sugars recovery from autohydrolysis of pineapple waste
[Excerpt] The aim of this research was to evaluate the influence of temperature, time and mass/ volume ratio on the release of sugars and polyphenols using an autohydrolysis procedure from pineapple waste. A Box-Bhenken design was used with three factors (time, temperature and mass/volume ratio) and three levels was used. All treatments were performed in triplicate. Nine central points were used. For autohydrlosysis treatments, an oil bath was used [1]. After autohydrolysis, liquid phases or hydrolysates were analyzed for glucose and fructose concentration by high performance liquid chromatography (HPLC) [2]. The FolinCiocalteu assay was used to measure total polyphenols of hydrolysates [3] and HPLC to identify these molecules [4]. (...
Searching Data: A Review of Observational Data Retrieval Practices in Selected Disciplines
A cross-disciplinary examination of the user behaviours involved in seeking
and evaluating data is surprisingly absent from the research data discussion.
This review explores the data retrieval literature to identify commonalities in
how users search for and evaluate observational research data. Two analytical
frameworks rooted in information retrieval and science technology studies are
used to identify key similarities in practices as a first step toward
developing a model describing data retrieval
Autohydrolysis extraction of bioactive compounds from pineapple waste
The aim of this research was to evaluate the influence of temperature, time and
mass/volume ratio on the release of sugars and polyphenols using an autohydrolysis procedure
from pineapple waste and determine its antioxidant activity. A Box-Bhenken design was used with
three factors (time, temperature and mass/volume ratio) at three levels. All treatments were
performed in triplicate. For autohydrolysis treatments, an oil bath was used [1]. After extraction
process, liquid phases or hydrolysates were analyzed for glucose and fructose concentration by
high performance liquid chromatography (HPLC) [2]. The Folin-Ciocalteu assay was used to
measure total polyphenols of hydrolysates [3] and HPLC to identify these molecules [4]. Free
radical scavenging activity (DPPH assay) and radical cation decolorization assay (ABTS) were
assayed [5].
Figure 1, shows the antioxidant activity obtained from experimental matrix Box-Bhenken design
from autohydrolysis treatments of pineapple waste. It was observed most treatments have higher
activity than control, this is due to the abundance of bioactive compounds present in the
hydrolysates.
Conclusion: Autohydrolysis process is a good alternative for an effective extraction (using water
as only reaction medium) of value-added compounds that can be used for alcoholic drinks
enriched with natural antioxidants. In addition, this technology is an environmentally friendly
extraction alternative in compared with traditional chemical process
Valorization of wastes from agrofood and pulp and paper industries within the biorefinery concept: southwestern Europe scenario
Nowadays, the need to attain a sustainable society increasingly demands for the development of an economy based on biorefineries. In Southwestern Europe, agrofood and forest industries produce significant amount of wastes that could satisfy the demand for renewable biomass to be used in a biorefinery scheme alternatively to traditional uses of these residues. This chapter will primarily cover the current scenario regarding the annual volume of residues generated by agrofood (cheese whey, vine pruning waste, and brewer's spent grains) and pulp and paper industry (sawdust, chips, bark, and sludge). Additionally, the present-day use and final destination of these wastes and their main environmental issues will be described and discussed; besides, advanced valorization strategies (e.g., fuels and chemicals) involving a biorefinery approach will be approached, based on current reports according to the chemical composition of each waste. Finally, new insights on valorization of wastes from agrofood and pulp and paper industries, its challenges, and trends for future research will be presented.(undefined)info:eu-repo/semantics/publishedVersio
Biorefinery approach for the valorization of vine pruning residue
Lignocellulosic biomass (namely vine pruning residue, VPR) conversion into biofuels is considered a promising alternative to replace fossil fuels. In this work, VPR was submitted to hydrothermal treatment under isothermal conditions (180 and 200oC for 10-90min), in order to assess the effect of the treatment on the VPR fractionation. Liquid phase was analyzed for oligosaccharides composition and solid phase was submitted to enzymatic saccharification at liquid to solid ratio of 25 g/g and enzyme to substrate ratio of 25 FPU/g for glucose production. 62% of xylan was solubilized into xylose and xylooligosaccharides (2 and 11 g/L) and 70-98% of glucan remained in the pretreated VPR. Enzymatic saccharification of pretreated VPR was improved with the hardness of treatment. Overall, hydrothermal process (180oC, 60 min) was suitable for the production of xylose and xylooligosaccharides and to obtain a susceptible treated biomass for glucose production (13 g/L with 73% of conversion).CNPqCAPESBraskemPortuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI- 01-0145-FEDER-006684), Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER- 027462), INOU 15-08 project (supported by DeputaciĂłn de Ourense
Effect of circular motion exercise on bone modeling and bone mass in young rats: An animal model of isometric exercise
The aims of the study are to develop a non-invasive animal model of circular motion exercise and to evaluate the effect of this type of exercise on bone turnover in young rats. The circular motion exercise simulates isometric exercise using an orbital shaker that oscillates at a frequency of 50 Hz and is capable of speeds from 0-400 rpm. A cage is fixed on top of the shaker and the animals are placed inside. When the shaker is turned on, the oscillatory movement should encourage the animals to hold on to the cage and use various muscle forces to stabilize themselves. Rats at 8 weeks of age were trained on the shaker for 6 weeks and static and dynamic histomorphometric analyses were performed for the proximal tibial metaphysis and the tibial shaft. The exercise resulted in no significant effect on animal body weight, gastrocnemius muscle weight and femoral weight. Although the bone formation rate of cancellous and cortical periosteum was increased by the exercise, trabecular bone volume was decreased. The exercise increased periosteal and marrow perimeters and the cross-sectional diameter of cortical bone from medial to lateral without a significant increase in the cortical bone area. These results suggest that circular motion exercise under force without movement or additional weight loading will cause bone-modeling drift with an increase in bone turnover to reconstruct bone shape in adaptation to the demand in strength. Since there is no additional weight loading during circular motion exercise, the net mass of bone is not increased. The bone mass lost in trabecular bone could possibly be due to a re-distribution of mineral to the cortical bone
Integral valorization of vine pruning residue by sequential autohydrolysis stages
Wine processing generates a large amount of residue, in particular pruning residue of vine. In this work, autohydrolysis in two sequential stages was proposed for the integral valorization of this residue. In a first stage, vine pruning residue was submitted to autohydrolysis treatment at 180 °C for 60 min (severity of 4.13) and liquid to solid ratio of 6 g water per g vine pruning residue. In these conditions, 63.7% of xylan was recovered in the liquid phase as xylooligosaccharides (17 g/L) and 2.35 g/L of phenolic compounds with antioxidant activity were also extracted. Autohydrolyzed vine pruning residue was subjected to a second autohydrolysis at temperature in the range 180200 °C and time 3040 min. After sequential treatments, enzymatic hydrolysis of cellulose was significantly improved from 73% to 99% of conversion. At selected conditions (severity of 4.60), ethanol production was successfully obtained from two strategies of, separately and simultaneously, saccharification and fermentation, thus achieving ethanol yield of 96 and 83%, respectively. Overall, two sequential stages of the process allowed the recovery of 13.7 kg of xylooligosaccharides, 3.1 kg of phenolic compounds, 13.1 kg of ethanol and 27 kg of lignin per 100 kg of vine pruning residue. Sequential autohydrolysis stages were shown as a suitable strategy for the integral valorization of vine pruning residue.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operational Regional do Norte. Meirielly S Jesus thanks her fellowship (Ref. 202259/2014-5) supported by the International Cooperation Program CNPq/CSF at the University of Minho financed by CNPq-Brazilian Federal Agency. Aloia Romani thanks financial support obtained by Deputation de Ourense (Ref. INOU 15-08).info:eu-repo/semantics/publishedVersio
Evaluation of alternative alkali pretreatment for oat straw saccharification and fermentation
ECO-BIO 2016Introduction: Lignocellulosic biofuels production requires the sustainable pretreatment for its processing. Lime pretreatment is considered an alternative alkali pretreatment, easily to recover and inexpensive that allows to operate under milder conditions of temperature and pressure. The aim of this work was the evaluation of lime pretreatment for bioethanol production from oat straw.
Methods: Oat straw was subjected to lime pretreatment at liquid to solid ratio of 10 g/g. The following operational conditions of lime pretreatment were evaluated: temperature (in the range 90-134 ÂșC), time (30-120 min) and Ca(OH)2/g (01-04 g/g). The pretreated oat straw was recovered by filtration, washed until pH=7 and analysed for chemical composition. The enzymatic susceptibility of lime pretreated solids was evaluated under favourable conditions of solid and enzymes loadings (25 g/g and 25 FPU of CellicTec2/g). Selected condition of lime pretreatment (134 ÂșC, 30 min and 0.1 g of Ca(OH)2/g of oat straw) was used for the bioethanol production by simultaneous saccharification and fermentation (14 % of solids and 20 FPU/g) using an industrial Saccharomyces cerevisiae PE-2 strain and its metabolic engineered version (MEC1133) for xylose consumption.
Results and Discussion: Under selected conditions (134 ÂșC for 30 min and a Ca(OH)2 load of 0.1g/g) 96 % of glucan and 77 % of xylan were recovered and 42 % of delignification was achieved. Moreover, the lime pretreatment allowed enhancing the enzymatic saccharification achieving 75 % of glucan to glucose conversion and 100 % of xylan to xylose conversion. The use of MEC1133 strain increased a 20 % of ethanol concentration comparing to PE-2 obtaining 41 and 34 g/L of ethanol, respectively. This work provides a suitable process for the fractionation of oat straw. Lime pretreatment yields a pretreated raw material with high polysaccharide content susceptible to be efficiently converted into ethanol.info:eu-repo/semantics/publishedVersio
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