Abstract:
:Supercritical fluids offer environmental advantages over chemical solvents, while providing enhanced separation and chemical selectivity. The use of supercritical fluids for the recovery of products from biomass and the transformation of selected molecules (to add value) was studied. Free fatty acids were bio-catalytically transformed to fatty acid esters using lipase within a supercritical fluid environment. A central composite rotatable design was used to evaluate the influence of operating conditions on the enzymatic esterification process and a response surface equation was optimized to identify the most favourable process conditions for maximum free fatty acid conversion. Based on the model equation the process conditions under which it was predicted a yield of 100% esters could be obtained were: pressure 200 bar, temperature 60 °C, ethanol concentration 2.0 M, enzyme concentration 11 wt.% and time 60 min. Experiments conducted under these conditions gave an ester yield of 94.3% (close to predicted results). The activity per unit mass of biocatalyst was found to be 1585 μmol/min/g(cat). The results support the use of supercritical fluids for process integration.
journal_name
Enzyme Microb Technoljournal_title
Enzyme and microbial technologyauthors
Baig MN,Santos RC,Zetzl C,King J,Pioch D,Bowra Sdoi
10.1016/j.enzmictec.2011.07.004subject
Has Abstractpub_date
2011-09-10 00:00:00pages
420-6issue
4eissn
0141-0229issn
1879-0909pii
S0141-0229(11)00164-5journal_volume
49pub_type
杂志文章abstract::Myriococcum thermophilum cellobiose dehydrogenase (MtCDH) was expressed in Pichia pastoris using the pPICZαA expression vector under the control of methanol inducible AOX promoter. The purified recombinant MtCDH with a specific activity of 3.1 Umg(-1) was characterized to obtain kinetic constants for various carbohydr...
journal_title:Enzyme and microbial technology
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更新日期:2013-01-10 00:00:00
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journal_title:Enzyme and microbial technology
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abstract::Bacterial chitinases recruited multiple accessory domains for the conversion of recalcitrant polysaccharides to simple soluble sugars/amino sugars. Here, we report detailed properties of a multi-domain GH18 chitinase from Enterobacter cloacae subsp. cloacae (EcChi2) that preferred β-chitin as substrate. EcChi2 exhibit...
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2018.04.007
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journal_title:Enzyme and microbial technology
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
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更新日期:2016-07-01 00:00:00
abstract::The xylanase R8 gene (xynR8) from uncultured rumen fungi was cloned and successfully expressed in Lactobacillus reuteri. A xylanase activity of 132.1 U/mL was found in the broth of L. reuteri R8, the transformant containing pNZ3004 vector with xynR8 gene insertion. Two distinct forms of recombinant xylanase with diffe...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2014.06.004
更新日期:2014-10-01 00:00:00
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2017.11.005
更新日期:2018-03-01 00:00:00
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2019.109372
更新日期:2019-12-01 00:00:00
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2014.11.005
更新日期:2015-03-01 00:00:00
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/0141-0229(91)90106-k
更新日期:1991-11-01 00:00:00
abstract::Anthocyanin production by strawberry cells depends not only on light intensity but also on the light/dark cycle operation with hour- or second-scale periods. These findings are useful for designing and operating photobioreactors for enhanced anthocyanin production. Intermittent illumination with a second-scale period ...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/s0141-0229(00)00143-5
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journal_title:Enzyme and microbial technology
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章,评审
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journal_title:Enzyme and microbial technology
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journal_title:Enzyme and microbial technology
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更新日期:2015-04-01 00:00:00
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
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abstract::Chemical modification of lysine residues in two bacterial alpha-amylases, a mesophilic enzyme from Bacillus amyloliquefaciens (BAA) and a thermophilic enzyme from Bacillus licheniformis (BLA) was carried out using citraconic anhydride. 13 +/- 1 residues in BAA and 10 +/- 1 residues in BLA were found modified under def...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
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abstract::The heat and mass transfer have been proved to be the important factors in air pressure pulsation for cellulase production. However, as process of enzyme secretion, the cellulase formation has not been studied in the view of microorganism metabolism and metabolic key enzyme activity under air pressure pulsation condit...
journal_title:Enzyme and microbial technology
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更新日期:2014-03-05 00:00:00
abstract::Production of laccase activity by nine strains of Chalara paradoxa isolated from olive mill wastewater disposal ponds were studied. Enzyme extracts obtained from cultured broths by adsorption on hydroxyapatite showed a single band of laccase activity on ABTS after polyacrylamide gel electrophoresis (PAGE). They showed...
journal_title:Enzyme and microbial technology
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journal_title:Enzyme and microbial technology
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更新日期:2016-05-01 00:00:00
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journal_title:Enzyme and microbial technology
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journal_title:Enzyme and microbial technology
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journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2015.06.015
更新日期:2015-11-01 00:00:00
abstract::A solvent-mediated method (SMM) was used to prepare supersaturated sugar solutions in hydrophobic and mixture of hydrophilic/hydrophobic ionic liquids (ILs), namely, [Bmim][Tf2N] and [Bmim][TfO]/[Bmim][Tf2N], respectively. In this method, sugars were first solubilized in a mixture of organic solvent and water (i.e. me...
journal_title:Enzyme and microbial technology
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abstract::Alginate was evaluated as an immobilization matrix for enzyme-catalyzed reactions in organic solvents. In contrast to most hydrogels, calcium alginate was found to be stable in a range of organic solvents and to retain the enzyme inside the gel matrix. In hydrophobic solvents, the alginate gel (greater than 95% water)...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
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更新日期:1992-01-01 00:00:00