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1.
Food Res Int ; 182: 114160, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519185

RESUMO

Aqueous enzymatic extraction (AEE) of macauba pulp oil (MPO) was performed in this study with five commercial enzymatic pools. The chemical, nutritional, and thermal properties of the oils with high oil efficiency by AEE were evaluated and compared with mechanical pressing (MP) and organic solvent extraction (SE). Among the AEE processes, the pectinase pool (at pH 5.5 and 50 °C) exhibited the highest process efficiency (88.6 %). The oils presented low acidity values (0.4-3.1 %) and low molar absorptivities, indicating minimal oil degradation. Bioactive compounds, such as carotenoids, were found in MPO. The iodine index and the fatty acid profile of the oils revealed a high content of unsaturated fatty acids, particularly oleic and linoleic acids, with excellent nutritional scores, as evidenced by anti-atherogenicity and anti-thrombogenicity indices. These findings emphasized that AEE is an eco-friendly approach for extracting high-quality MPO with beneficial health compounds for food products.


Assuntos
Ácidos Graxos , Óleos de Plantas , Óleos de Plantas/química , Ácidos Graxos/análise , Ácidos Graxos Insaturados/análise , Antioxidantes/análise , Sementes/química , Água/análise
2.
Food Res Int ; 179: 114016, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342537

RESUMO

Chocolate is a worldwide consumed food. This study investigated the fortification of sugar-free white chocolate with Lacticaseibacillus rhamnosus GG microcapsule co-encapsulated with beet residue extract. The chocolates were evaluated for moisture, water activity, texture, color properties, melting, physicochemical, and probiotic stability during storage. Furthermore, the survival of L. rhamnosus GG and the bioaccessibility of phenolic compounds were investigated under in vitro simulated gastrointestinal conditions. Regarding the characterization of probiotic microcapsules, the encapsulation efficiency of L. rhamnosus GG was > 89 % while the encapsulation efficiency of phenolic compounds was > 62 %. Chocolates containing probiotic microcapsules were less hard and resistant to breakage. All chocolates had a similar melting behavior (endothermic peaks between 32.80 and 34.40 °C). After 120 days of storage at 4 °C, probiotic populations > 6.77 log CFU/g were detected in chocolate samples. This result demonstrates the potential of this matrix to carry L. rhamnosus GG cells. Regarding the resistance of probiotic strains during gastric simulation, the co-encapsulation of L. rhamnosus GG with beet extract contributed to high counts during gastrointestinal transit, reaching the colon (48 h) with viable cell counts equal to 11.80 log CFU/g. Finally, one of our main findings was that probiotics used phenolic compounds as a substrate source, which may be an observed prebiotic effect.


Assuntos
Beta vulgaris , Chocolate , Lacticaseibacillus rhamnosus , Cápsulas , Extratos Vegetais
3.
Food Bioproc Tech ; : 1-17, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37363380

RESUMO

Techniques capable of producing small-sized probiotic microcapsules with high encapsulation yields are of industrial and scientific interest. In this study, an innovative membrane emulsification system was investigated in the production of microcapsules containing Lacticaseibacillus rhamnosus GG® (Lr), sodium alginate (ALG), and whey protein (WPI), rice protein (RPC), or pea protein (PPC) as encapsulating agents. The microcapsules were characterized by particle size distribution, optical microscopy, encapsulation yield, morphology, water activity, hygroscopicity, thermal properties, Fourier-transform infrared spectroscopy (FTIR), and probiotic survival during in vitro simulation of gastrointestinal conditions. The innovative encapsulation technique resulted in microcapsules with diameters varying between 18 and 29 µm, and encapsulation yields > 93%. Combining alginate and whey, rice, or pea protein improved encapsulation efficiency and thermal properties. The encapsulation provided resistance to gastrointestinal fluids, resulting in high probiotic viability at the end of the intestinal phase (> 7.18 log CFU g-1). The proposed encapsulation technology represents an attractive alternative to developing probiotic microcapsules for future food applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s11947-023-03099-w.

4.
Biotechnol Lett ; 45(2): 287-298, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36592260

RESUMO

Lipase B from Candida antarctica (CalB) is one of the biocatalysts most used in organic synthesis due to its ability to act in several medium, wide substrate specificity and enantioselectivity, tolerance to non-aqueous environment, and resistance to thermal deactivation. Thus, the objective of this work was to treat CalB in supercritical carbon dioxide (SC-CO2) and liquefied petroleum gas (LPG), and measure its activity before and after high-pressure treatment. Residual specific hydrolytic activities of 132% and 142% were observed when CalB was exposed to SC-CO2 at 35 â„ƒ, 75 bar and 1 h and to LPG at 65 â„ƒ, 30 bar and 1 h, respectively. Residual activity of the enzyme treated at high pressure was still above 100% until the 20th day of storage at low temperatures. There was no difference on the residual activity loss of CalB treated with LPG and stored at different temperatures over time. Greater difference was observed between CalB treated with CO2 and flash-frozen in liquid nitrogen (- 196 â„ƒ) followed by storage in freezer (- 10 â„ƒ) and CalB stored in freezer at - 10 â„ƒ. Such findings encourage deeper studies on CalB as well as other enzymes behavior under different types of pressurized fluids aiming at industrial application.


Assuntos
Enzimas Imobilizadas , Lipase , Dióxido de Carbono , Proteínas Fúngicas
5.
Food Chem ; 404(Pt B): 134629, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36283308

RESUMO

Xanthohumol, a chalcone unique to hops, has attracted attention from researchers due to its several pharmacological effects on humans. In industry, hops are almost exclusively used in beer production, generating tons of solid waste - hot trub from the boiling step and spent hops from the dry hopping - rich in biocompounds, among them xanthohumol, that could be recovered and used for several nutritional purposes. The literature is extensive on extraction processes of xanthohumol directly from hops, but only a few studies present its recovery from brewery solid waste. We focus on presenting the xanthohumol characteristics and benefits for human consumption, and discuss the main extraction techniques, their advantages and limitations, to prospect strategies to recover this high-value compound from brewing solid waste. Recent extraction processes represent promising approaches to overcome the limitations of conventional methods, but further studies are still needed to understand xanthohumol extraction and purification and induce industrial upscaling.


Assuntos
Produtos Biológicos , Humulus , Propiofenonas , Humanos , Resíduos Sólidos , Flavonoides/análise
6.
Prep Biochem Biotechnol ; 52(9): 1051-1059, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35100517

RESUMO

The production of 2,3-butanediol (2,3-BDO), a dialcohol of great interest for the food, chemical, and pharmaceutical industry, through the fermentation of biomass, is a sustainable process strategic position for countries with abundant biomass generated by the agribusiness. However, the downstream process of 2,3-BDO is onerous due to the complexity of fermentation broth and the physical-chemical characteristics of the 2,3-BDO. This study investigated the feasibility of 2,3-BDO extraction from model aqueous solutions using aqueous two-phase systems (ATPS). A central composite rotational design (CCRD) was employed to evaluate different ATPS compositions and the influences on the 2,3-BDO recovery and partition coefficient. The polyethylene glycol (PEG) and different concentrations of sodium citrate, ammonium sulfate, and potassium phosphate were investigated. The concentration of salt and PEG in the ATPS was identified as the most significant factors influencing the recovery and partition coefficient of 2,3-BDO. The recovery of 2,3-BDO reached 94.5% and was obtained when the system was composed of 36.22% (w/w) of PEG 4000 and 4.47% (w/w) of potassium phosphate. The results indicate that ATPS based on PEG-salt has a high potential for industrial application, using mild conditions and a simple process for recovering and purifying the 2,3-BDO produced from microbiological synthesis.


Assuntos
Cloreto de Sódio , Água , Sulfato de Amônio , Butileno Glicóis , Fosfatos , Polietilenoglicóis/química , Compostos de Potássio , Cloreto de Sódio/química , Citrato de Sódio , Água/química
7.
Sci Total Environ ; 798: 148900, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34375249

RESUMO

Fouling growth in brackish water distribution systems (BWDS), especially calcium-silica fouling, is inevitable issue in brackish water desalination, chemical and agricultural industry, eventually threaten the cleaner production process and environment. Magnetic Field (MF) has been a greener and effective technology to control calcium carbonate fouling. However, the effects of MF on composite calcium-silica fouling are still elusive. Therefore, this paper assessed the effect of MF on calcium and silica fouling. We found that MF not only significantly reduce the calcium carbonate fouling, but also obviously decreased the silica fouling. The MF reduced the calcite fouling reached 38.2%-64.3% by changing water quality parameters to trigger the transformation rate of CaCO3 crystal from compact calcite to looser aragonite, as well as increase the unit-cell parameters and chemical bond lengths of calcite and aragonite. The MF also decreased the content of silica fouling (silica and silicate) reached 22.4-46.3% by reducing the concentration of soluble silica and accelerating the flocculation settlement to form large size solid particles in BW. Furthermore, MF broke the synergistic interactions among calcium and silica fouling. In addition, the anti-fouling ability of permanent MF was higher by 12.3-35.1% than electric MF. Overall, these findings demonstrate that MF is an effective and chemical-free technology to control calcium-silica fouling in BWDS, and provide a new perspective for sustainable application of brackish water.


Assuntos
Cálcio , Dióxido de Silício , Carbonato de Cálcio , Campos Magnéticos , Membranas Artificiais , Águas Salinas
8.
J Food Sci Technol ; 58(3): 1093-1100, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33678892

RESUMO

Membrane technology is an interesting alternative to conventional gelatin clarification methods, resulting in the elimination of refining chemical agents. In this work, the application of a permanent magnetic field as a pre-treatment of the gelatin solutions was proposed as a strategy to improve the microfiltration (MF) performance. Filtration tests were performed using a 1.5% swine gelatin solution at 40 °C through cellulose acetate membranes in a tangential flow module. Prior to the filtrations, the feed solutions were pretreated by the circulation of the solution through magnetic fields with different flux densities, 0.7 T and 1.34 T, for 2 h. The magnetic induction of the solution significantly increased the permeate flux and the recovery of hydraulic permeance by 63% and 122%, respectively, showing the application of the magnetic field in the solution of gelatin is an attractive alternative to improve the performance of the process.

9.
Plant Foods Hum Nutr ; 76(1): 90-97, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33517518

RESUMO

Jambolan is an unexplored fruit rich in bioactive compounds like anthocyanins, catechin, and gallic acid. Thus, the extraction of bioactive compounds allows adding value to the fruit. In this context, the present study reports the recovery and concentration of jambolan fruit extract by ultra and nanofiltration for the first time. Acidified water was used to extract polyphenols from the pulp and peel of jambolan. The extracts were concentrated using ultrafiltration and nanofiltration membranes with nominal molecular weight cut-off ranging from 180 to 4000 g mol-1. Total monomeric anthocyanin, total phenolic compounds, and antioxidant capacity were analyzed. Phenolic compounds were quantified, and anthocyanins were identified by high-performance liquid chromatography coupled to diode-array detection and mass spectrometry (HPLC-DAD-MS). Concentration factors higher than 4.0 were obtained for anthocyanins, gallic acid, and catechin after nanofiltration of the extracts. Other compounds such as epicatechin, p-Coumaric acid, and ferulic acid were quantified in the concentrated extract, and the main anthocyanins identified were 3,5-diglucoside: petunidin, malvidin, and delphinidin. Therefore, jambolan extract showed a high potential to be used as a natural dye and antioxidant in food products.


Assuntos
Syzygium , Antocianinas/análise , Antioxidantes , Cromatografia Líquida de Alta Pressão , Frutas/química , Fenóis/análise , Extratos Vegetais
10.
Environ Technol ; 42(1): 126-133, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31132009

RESUMO

Poultry processing plants generate large amounts of wastewater in the many steps necessary to provide high quality and safe products. Carcass chilling is one of these steps, where the temperature of the carcass is reduced from 40°C to 4°C, for reducing the growth rate of microorganisms and affecting flavour, texture and appearance. In this operation, carcasses are continually displaced through a series of two tanks (called pre-chiller and chiller) filled with cold water, thus being responsible for a considerable amount of wastewater generation. This work aimed to regenerate the wastewater of the pre-chiller tank employing microfiltration (pore size 0.10 and 0.20 µm) and ultrafiltration (UF; MWCO 10 and 50 kDa) polymeric membranes in bench and pilot scales, with the final purpose of reuse. Membrane performance was evaluated in terms of the capacity of removing the contaminants and producing sufficient permeate flux in different working pressures. Bench-scale UF membrane presented the highest initial permeate flux of 112.1 L/m2h at 200 kPa. The four membranes tested presented good retention of microorganisms, with apparent rejection of up to 100%. Pilot-scale membranes presented better apparent rejection, with retentions above 99% for turbidity, apparent colour and fat content. Moreover, organic matter retention was also very high, up to 94% for chemical oxygen demand and 92% for total organic carbon. The use of membranes seems to be a promising approach for recycling and reuse of poultry pre-chiller wastewater.


Assuntos
Galinhas , Purificação da Água , Animais , Membranas Artificiais , Ultrafiltração , Eliminação de Resíduos Líquidos , Águas Residuárias , Água
11.
Environ Sci Pollut Res Int ; 26(32): 33014-33022, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31512133

RESUMO

Swine production chain generates residues with potential application in environmental processes. This study aimed at the use of swine hair as a potential biofilter for hexavalent chromium (Cr(VI)) removal from wastewater of tannery industry. The hair was pretreated using H2O2 in alkaline medium, and statistical analysis was carried out to evaluate the hair degradation, as well the Cr(VI) removal by the potential pretreated biofilter. The results showed 99% of Cr(VI) removal in 105 min of treatment in large pH range (1-10). Treated and untreated effluents were submitted to cytotoxicity study using vegetable and animal cells, demonstrating a significant reduction on toxicity to both cells. Therefore, swine hair demonstrated to be a promising residue for heavy metal removal on the perspective of an environmentally friendly technique.


Assuntos
Cromo/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Animais , Peróxido de Hidrogênio/análise , Metais Pesados/análise , Suínos , Águas Residuárias/química
12.
Bioprocess Biosyst Eng ; 42(5): 677-685, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30661103

RESUMO

This study evaluated the production of cellulolytic enzymes from different agricultural residues. The crude enzyme extract produced was characterized and applied for saccharification of some agricultural residues. Maximum cellulolytic activities were obtained using soybean hulls. All enzymatic activities were highly stable at 40 °C at a pH range of 4.5-5.5. For stability at low temperatures, the enzyme extract was stored at freezing temperature and cooling for about 290 days without major loss of activity. The Km values found for total cellulase (FPase), endoglucanase (CMCase), and xylanase were 19.73 mg ml-1, 0.65 mg ml-1, and 22.64 mg ml-1, respectively, and Vmax values were 0.82 mol min-1 mg-1, 0.62 mol min-1 mg-1, and 104.17 mol min-1 mg-1 to cellulose, carboxymethyl cellulose, and xylan, respectively. In the saccharification tests, the total amount of total reducing sugars (TRS) released from 1 g of soybean hulls catalyzed by the enzymes present in the crude enzyme extract was 0.16 g g-1 dry substrate.


Assuntos
Biocombustíveis , Celulase , Proteínas Fúngicas , Trichoderma/enzimologia , Celulase/química , Celulase/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Temperatura Alta , Concentração de Íons de Hidrogênio
13.
Int J Biol Macromol ; 122: 653-658, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30416097

RESUMO

Alternatives to improve the stability and activity of enzymes have been rising in the last years due to the potential industrial application of these catalysts. However, the enzymes characteristics in terms of stability and catalytic efficiency can reduce, in some cases, due to the reaction conditions. Due to a lack in the literature concerning structural information related to the new commercial Eversa® Transform 2.0 enzyme (NS-40116) we investigated the conformational structure by spectroscopic and mass spectrometry techniques after exposure in permanent magnetic flux density (0.7 and 1.34 T) in recirculation mode (1, 2, and 4 h) at 0.06 L·min-1. The influence of pH on the enzymatic solution associated with the magnetic flux (pH 5, 7, and 9) was also evaluated. Under the best reaction condition (pH 7 after 4 h in a recirculation mode at 1.34 T), enzyme activity 77% higher than the control sample was obtained. Mass spectrometry techniques showed changes in the NS-40116 tertiary structure. Thus, the application of magnetic fields as an enzymatic pre-treatment showed to be a promising technique and a viable alternative to increase the enzymatic activity since it is a low cost, environmentally friendly, and ease operation process.


Assuntos
Lipase/química , Lipase/metabolismo , Campos Magnéticos , Biocatálise , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Cinética
14.
Bioresour Technol ; 272: 510-520, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30391844

RESUMO

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 ±â€¯2.9 g/100 g husks) and E (39.5 ±â€¯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.


Assuntos
Metabolismo dos Carboidratos , Fermentação , Oryza/metabolismo , Água/metabolismo , Biomassa , Carboidratos , Hidrólise , Cinética , Temperatura
15.
Water Res ; 130: 105-114, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29202342

RESUMO

Strategies to control biofouling without using antimicrobial chemicals are needed to prevent the spread of antibiotic resistance genes and disruption of microbial activities in biological treatment. This study developed an environmentally friendly biofouling resistant membrane by incorporating d-tyrosine onto a commercial nanofiltration membrane using FAU type zeolite nanoparticles that covalently bound to the membrane surface as carriers for slow release. The d-tyrosine loaded membrane had similar water permeability as the unmodified membrane, but greatly reduced initial cell attachment and strongly inhibited subsequent biofilm formation without inactivating the bacteria. The membrane slowly released d-tyrosine in the time course of over 5 days, and retained its anti-biofouling capability in repeated 24 h efficacy tests for as long as 6 days. In nanofiltration operation, the d-tyrosine incorporated zeolite coating completely inhibited cell adhesion on the membrane surface and significantly alleviated membrane flux decline.


Assuntos
Incrustação Biológica/prevenção & controle , Nanocompostos/química , Tirosina/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Membranas Artificiais , Permeabilidade
16.
J Food Sci Technol ; 54(10): 3366-3369, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28974822

RESUMO

This short note compares the chemical profile of pecan nut oil samples obtained from pressurized n-butane and cold pressing with two commercial oils. The conventional cold pressing technique yielded 58.9 wt%, while pressurized n-butane yielded from 53 to 65 wt%, being the highest yield at 55 °C, and pressure of 40 bar. The n-butane behaves nearly like a piston fluid within the experimental conditions used. The results showed that the extraction variables had a slight influence on the fatty acid composition of the samples. Extraction with n-butane thus showed to be a promising alternative technique to conventional extraction methods, as very mild operating conditions and eco-friendly solvent can be used to provide good results without any residues in the final product.

17.
An Acad Bras Cienc ; 89(1): 57-63, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28423073

RESUMO

The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min.


Assuntos
Álcoois/química , Precipitação Química , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Concentração Osmolar , Cloreto de Cálcio/química , Meios de Cultura/química , Kluyveromyces/química , Kluyveromyces/isolamento & purificação , Valores de Referência , Reprodutibilidade dos Testes , Sais/química , Cloreto de Sódio/química , Solventes/química
18.
J Food Sci Technol ; 54(3): 846-851, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28298700

RESUMO

The extraction of litchi (Litchi chinensis Sonn.) and oat (Avena sativa L.) seeds were investigated using n-butane as pressurized solvent by evaluating the effect of pressure in the range of 7-100 bar and temperature from 25 to 70 °C on the extract yield and chemical composition together with the antioxidant activity of the extracts obtained. It was experimentally observed extraction yields for both seeds up to ~3.5 wt%, with a total phenolic content around 126.4 mg GAE/100 g of extract, and an antioxidant activity up to 78.36%. Oat seeds extract presented higher values of these parameters evaluated compared to litchi extract. Based on the results found, it seems that n-butane may be a promising solvent to conventional extraction methods, as mild operating conditions and eco-friendly solvent can be used to provide good results without any residues in the final product.

19.
An. acad. bras. ciênc ; 89(1): 57-63, Jan,-Mar. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-886625

RESUMO

ABSTRACT The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min.


Assuntos
Concentração Osmolar , Precipitação Química , Álcoois/química , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/química , Valores de Referência , Sais/química , Solventes/química , Kluyveromyces/isolamento & purificação , Kluyveromyces/química , Cloreto de Cálcio/química , Cloreto de Sódio/química , Reprodutibilidade dos Testes , Meios de Cultura/química
20.
Environ Technol ; 38(23): 2928-2938, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28088876

RESUMO

The separation of Jatropha curcas oil from azeotropes of ethyl alcohol-n-hexane and isopropyl alcohol-n-hexane using ceramic membranes with different cutoffs (5, 10 and 20 kDa) is presented. The mass ratios of oil:azeotropes (O:S) studied were 1:3 for feeding pressures of 0.1, 0.2 and 0.3 MPa, and 1:1 for the feeding pressure of 0.1 MPa. Isopropyl alcohol was the best solvent for the membranes conditioning to permeate n-hexane (240 kg/m2 h). In the separation of J. curcas oil and azeotropes of solvents, both membranes showed oil retention and total flux decreases with time. Overall, the lowest decrease in the retentions was reached in the 5 kDa membrane, while the lowest decrease in the total flux was reached in the 20 kDa. In the separation of oil and ethyl alcohol-n-hexane azeotrope, the best retention at 60 min of the process was equal to 17.3 wt% in the 20 kDa membrane at 0.3 MPa and O:S ratio equalled to 1:3. In this condition, the total permeate flux was 17.5 kg/m2 h. Different retentions and permeabilities are provided when changing the O:S ratio, the feeding pressure and the molecular weight cutoff of membranes.


Assuntos
Cerâmica/química , Fracionamento Químico/métodos , Jatropha/química , Óleos de Plantas/isolamento & purificação , Solventes/química , 2-Propanol/química , Hexanos/química , Membranas Artificiais , Óleos de Plantas/química
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