This work is focused on the optimization of process conditions of the ultrasound-assited extraction that promote high yields of lipids from freeze-dried cells of Mortierella isabellina produced by ...submerged fermentation. The influence of ultrasound intensity (26.89 W cm−2 - 85.00 W cm−2) and pulse cycle (0.57–1.0) using chloroform:methanol:water (2:1:0.8, v/v/v) mixture and ethanol was evaluated on the yields fatty acids and it was compared with extractions without ultrasound and conventional Soxhlet method. Ultrasound intensity of 75.11 W cm−2 and pulse factor of 0.93 were the optimized conditions in the central composite design, yielding 14.46 wt% and 19.49 wt% of fatty acids using ethanol and chloroform:methanol:water as solvents, respectively. The fatty acids profile was similar for all extractions. The results show the lipids yields were higher when ultrasound was applied in biomass from fungus Mortierella isabellina.
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•Fatty acids were extracted with ultrasound using different solvents.•Ultrasound intensity and pulse factor were optimized in the central composite design.•Mixture of solvents (chloroform:methanol:water) provided better yields of lipids.•The yields of lipids were strongly improved for the ultrasound intensity.•Ultrasound-assisted extraction with ethanol was advantageous for higher concentration of fatty acids in the oil.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The increasing interest in reusing coproducts from rice crops, such as straw, husks, and bran, has motivated the writing of this review. The aim is to provide a critical and constructive overview of ...the main advantages and technological challenges for further processing such coproducts within the biorefinery concept. Current studies and applications are presented and discussed, which mainly include the use of such coproducts on energy and biofuel generations, production of building blocks, adsorption of recalcitrant substances, animal feeding and fertilization crops, extraction of bioactive compounds, and production of carbon-based and silica-based materials. Furthermore, the reality and expectations on processing steps (chemical, biochemical, and thermochemical routes), conventional and novel technologies and value-added products/derivatives with interest in several industrial fields are highlighted. As expectations, some companies and government projects are innovating and trying to use sub/supercritical water hydrolysis as a promising technology with high potential to decompose rice lignocellulosic biomass into small-chain sugars and bioproducts. Overall, as a future outlook for making most of the processing routes of rice coproducts more feasible, more infrastructure and scientific researches are needed to overcome some barriers and drawbacks that still exist in the subject presented in this review.
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•Reasons for further processing rice coproducts are presented and discussed.•Technologies and processes are approached within the biorefinery concept.•Advantages, technological challenges, and current applications of rice coproducts are highlighted.•Energy and biofuel generation, extraction of compounds, and production of materials are provided.•One promising expectation is the rice cellulosic hydrolysis by sub/supercritical water.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Subcritical water hydrolysis produced fermentable sugars at 220 °C.•Ethanol was produced from soybean straw and hull hydrolysates.•The yeast Wickerhamomyces sp. UFFS-CE-3.1.2 was ...used.•The fermented hydrolysates of straw increased biogas production by more than 60%.
The objective of this study was to evaluate the ethanol production by Wickerhamomyces sp. using soybean straw and hull hydrolysates obtained by subcritical water hydrolysis and, afterward, the biogas production using the fermented hydrolysates. Ethanol was produced using the straw and hull hydrolysates diluted and supplement with glucose, reaching 5.57 ± 0.01 g/L and 6.11 ± 0.11 g/L, respectively. The fermentation in a bioreactor with changing the pH to 7.0 allowed achieving maximum ethanol production of 4.03 and 3.60 g/L for straw and hull hydrolysates at 24 h, respectively. The biogas productions obtained for the fermented hydrolysates of straw with and without changing the pH were 739 ± 37 and 652 ± 34 NmL/gVSad, respectively. The fermented hydrolysate of hull without changing the pH presented 620 ± 26 NmL/gVSad. The soybean residues produced biofuels, indicating these residues show potential as raw material for renewable energy production.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Subcritical water hydrolysis produced up to 18 wt% reducing sugars from rice husks.•Conversion efficiency of 39 g/100 g carbohydrates was obtained at 220 °C.•The maximum content of ...levulinic acid (2.3 g/L) was obtained at 260 °C.•Dissociation of hemicelluloses is more efficient than dissociation of cellulose.
This work aimed at producing fermentable sugars and bioproducts from rice husks by subcritical water hydrolysis at 25 MPa in a semi-continuous mode. The influences of temperature (180 °C; 220 °C; 260 °C) and liquid/solid ratio (7.5 g water/g husks; 15 g water/g husks) on reducing sugar yield (YRS), efficiency (E), kinetic profiles (0–15 min), composition of sugars, inhibitors and organic acids, and physicochemical characteristics of the remaining solid material were evaluated and discussed in the work. The highest YRS (18.0 ± 2.9 g/100 g husks) and E (39.5 ± 1.7 g sugars/100 g carbohydrates) were obtained at 220 °C and 7.5 gwater/g husks. In such condition, the hydrolyzed solutions presented cellobiose (18.0 g/L), xylose 17.7 g/L), arabinose (3.6 g/L), glucose (1.5 g/L), and levulinic acid (0.7 g/L). The fermentable sugars and bioproducts can be applied in several industrial fields, especially for the production of bioethanol and other higher value-added chemical compounds.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Fungal biopolymers have gained considerable attention from the scientific community for various applications due to their biological and physicochemical properties. The wide applications in several ...areas, especially in the food industry as a bioemulsifier and in the agricultural area as a biosurfactant, have expanded the knowledge on the production of fungal biopolymers to keep up with developments on this subject area. Recent scientific studies have disclosed novel routes, optimized parameters, increased yields, and other related approaches in order to produce and apply fungal bioemulsifiers and biosurfactants. However, there is a need to gather important information in order to provide a way forward. Therefore, this review presents an overview of properties, applications, and perspectives for encouraging further projects and investments in the near future by most categories of investors. The selection of culture media, the definition of cultivation parameters, extraction, recovery, and purification are the initial steps to indicate the conditions for scale-up. Indeed, scale-up is still one of the challenges in this biotechnological field, which could be solved by expanding the tests and operational productions in both pilot and industrial plants.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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•Rice straw and husks were hydrolyzed by subcritical water to obtain solid products.•The products from the production of cellulosic bioethanol were used as adsorbents.•Straw ...hydrolyzed at 453 K showed the highest 2-nitrophenol removal efficiency.•The equilibrium adsorption was best described by the Langmuir isotherm model.•SEM and FT-IR analyses demonstrated changes in the lignocellulosic structure.
The potential of rice husks and straw as adsorbents after being processed by subcritical water hydrolysis (SWH) was investigated. The influences of temperature (453, 493 and 533 K) and liquid/solid ratio (7.5 and 15 g water/g biomass) on the rice straw and rice husks characteristics and on the adsorption capacity of 2-nitrophenol were evaluated at pH 4 and 7. Adsorption kinetics, equilibrium and thermodynamic parameters were also studied. The adsorption capacity was favored at pH 7. Pseudo-first-order model was suitable to predict the kinetic curves for 2-nitrophenol concentrations of 25, 50, 75 and 100 mg/L and the isotherm data obeyed the Freundlich model. Overall, the thermodynamic results revealed a spontaneous and exothermic process. The maximum adsorption capacity (92.97 ± 1.31 mg/g) was obtained for rice straw that has undergone an SWH at 453 K and 7.5 g water/g straw. The integration of processes to valorize co-products can make the production of cellulosic bioethanol more feasible.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Pecan raws were processed by subcritical water hydrolysis to obtain reducing sugars.•Different process conditions (temperature; water to solid mass ratio) were evaluated.•27.1 ± 6.9 g reducing ...sugars/100 g biomass were obtained at 220 °C for shells.•Efficiency in producing reducing sugars were up to 78 wt%.•The strategy proved to be a clean alternative for adding value to pecan coproducts.
Pecan cultivation has increased in recent years. Consequently, the amount of lignocellulosic residuals from its production has expanded. Thus, there is a necessity to explore and add value to their coproducts. The objective of this work was to obtain reducing sugars from pecan biomasses by the optimization of the subcritical water hydrolysis technology in a semi-continuous mode and the physicochemical and morphological characterization of these materials, such as SEM, TGA and FT-IR analysis. Temperatures of 180, 220 and 260 °C, water/solids mass ratio of 15 and 30 g water/g biomass and total reaction time of 15 min were used. The highest reducing sugar yield was 27.1 g/100 g of biomass, obtained at 220 °C and R-15 for pecan shells. TGA, SEM and FT-IR analysis indicated the modifications of structures and compositions of biomasses in fresh and hydrolyzed samples.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Chia seeds have a high oil content that consists primarily of omega-3 and omega-6 fatty acids, which are essential for humans. The technique used for chia oil extraction can be influences the final ...quality of the oil; thus, it is highly important to study the different extraction techniques. This study aimed to determine the extraction yield from different techniques and to evaluate the oils obtained. Chia oils were extracted by pressing, cold solvent and by supercritical CO2 with/without ultrasound and co-solvent (ethanol) and the oils were evaluated for their chemical and physicochemical characteristics. In addition, the extracted oils were compared with a commercial sample. By the use of previous ultrasonic steps and the addition of a cosolvent, it was possible to increase the yield using supercritical extraction. Among all of the studied techniques, pressing, although it resulted in the highest peroxide value, was the technique that produced the best chemical quality. In addition, a simple methodology for determination of the fatty acid composition of chia oil through 1H NMR spectroscopy was successfully applied, without need sample pre-treatment steps such as derivatization. Therefore, by evaluating the characteristics of the extracted chia oils, we determined that they can be an excellent source of omega-3 fatty acids for foods, medicines, and cosmetics.
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•Chia oil extraction with three techniques: supercritical, cold solvent and pressing.•Chemical and physical evaluation of chia oil obtained by the different techniques.•Comparison of techniques to determine oils fatty profile.•To suggest the use of chia oils in different areas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Microbial lipids are a valuable source of potential biofuels and essential polyunsaturated fatty acids. The optimization of the fermentation conditions is a strategy that affects the total lipid ...concentration. The genus Nigrospora sp. has been the target of investigations based on its potential bioherbicidal action. Therefore, this study developed a strategy to maximize the biomass concentration and lipid accumulation by Nigrospora sp. in submerged fermentation. Different media compositions and process variables were investigated in shaken flasks and bioreactor in batch and fed-batch modes. Maximum biomass concentration and lipid accumulations were 40.17 g/L and 21.32 wt% in the bioreactor, which was 2.1 and 5.4 times higher than the same condition in shaken flasks, respectively. This study presents relevant information to the production of fungal lipids since few investigations are exploring the fed-batch strategy to increase the yield of fungi lipids, as well as few studies investigating Nigrospora sp. to produce lipids.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
10.
Review on Microbial Lipases Production Treichel, Helen; de Oliveira, Débora; Mazutti, Marcio A ...
Food and bioprocess technology,
04/2010, Volume:
3, Issue:
2
Journal Article
Peer reviewed
This review paper provides an overview regarding the main aspects of microbial lipases production. The most important microbial lipase-producing strains for submerged and solid-state fermentations ...are reviewed as well as the main substrates, including the use of agroindustrial residues. Current process techniques (batch, repeated-batch, fed-batch, and continuous mode) are discussed and the main bioreactors configurations are also presented. Furthermore, the present review paper shows a general overview about the development of mathematical models applied to lipase production. Finally, some future perspectives on lipase production are discussed with special emphasis on lipase engineering and the use of mathematical models as a useful tool for process improvement and control.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
