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1.
A novel,two consecutive enzyme synthesis of feruloylated monoacyl- and diacyl-glycerols in a solvent-free system 总被引:1,自引:0,他引:1
Feruloylated mono- and di-acylglycerols were synthesized in a two step reaction: ethyl ferulate was first transesterified
with glycerol and then this was esterified with oleic acid. The yield of the combined feruloylated mono- and di-acylglycerols
in the second reaction reached 96% when esterification of 0.3 g transesterification products with 2.22 g oleic acid was catalyzed
with 0.25 g Candida antarctica lipase at 60°C under a vaccum of 10 mmHg for 1.33 h. 相似文献
2.
1-Pentyl, 1-hexyl and 1-heptyl ferulates were continuously synthesized at 60–90°C using a reactor system in which a column packed with ferulic acid powders and another column packed with immobilized Candida antarctica lipase particles were connected in series. Conversions greater than 0.9 were achieved for the synthesis of the 1-hexyl and 1-heptyl ferulates at 90°C. The system could be stably operated for the 1-heptyl ferulate synthesis at 90°C for at least two weeks. 相似文献
3.
Georgina Sandoval Paula G. Quintana Alicia Baldessari Antonio O. Ballesteros 《Biocatalysis and Biotransformation》2015,33(2):89-97
Lipophilic and stable derivatives of ferulic acid are required to improve its efficacy in fatty foods and to optimize its use in cosmetic and pharmaceutical preparations. We report an improved synthesis of ferulic acid monoesters (ethyl ferulate and lauryl ferulate) using immobilized lipase from Candida antarctica B (CALB) in diisopropyl ether (DIPE). Maximum yields were 89% and 85% in 200 h for ethyl and lauryl ferulate, respectively. Ethyl ferulate was further acylated with vinyl esters to form ferulate diesters. 4-Acetoxy-ethyl ferulate was obtained with the immobilized lipase from Alcaligenes sp. (QLG) with 59% yield in 72 h, whereas 4-dodecanoyloxy-ethyl ferulate (a new compound) was synthesized with 52% yield in 72 h using CALB. DIPE was the best solvent for the transesterifications. Finally, the anti-inflammatory activity of the synthesized derivatives was evaluated in vitro; the compounds bearing a dodecyl chain showed improved anti-inflammatory activity compared with short-chain esters. 相似文献
4.
In the present work we have evaluated synthesis of ethyl ferulate by the esterification reaction of ferulic acid and ethanol catalyzed by a commercial lipase (Steapsin) immobilized onto celite-545 in a short period of 6 h in DMSO. The immobilized lipase was treated with cross-linking agent glutaraldehyde (1%; v/v). The optimum synthesis of ethyl ferulate was recorded at 45 °C, pH 8.5 and 1:1 ratio of ethanol and ferulic acid. Co2+, Ba2+and Pb2+ ions enhanced the synthesis of ethyl ferulate Hg2+, Cd3+and NH4+ ions had mild inhibitory effect. The celite-bound lipase produced 68 mM of ethyl ferulate under optimized reaction conditions. 相似文献
5.
Mikko Uusi-Oukari Christian Ehnholm Matti Jauhlainen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,682(2):233
Phenylboronates are competitive inhibitors of serine hydrolases including lipases. We studied the effect of m-aminophenylboronate on triglyceride-hydrolyzing activity of hepatic lipase (EC 3.1.1.3). m-Aminophenylbo ronate inhibited hepatic lipase activity with a K1 value of 55 μM. Furthermore, m-aminophenylboronate protected hepatic lipase activity from inhibition by di-isopropyl fluorophosphate, an irreversible active site inhibitor of serine hydrolases. Inhibition of hepatic lipase activity by m-aminophenylboronate was pH-dependent. The inhibition was maximal at pH 7.5, while at pH 10 it was almost non-existent. These data were used to develop a purification procedure for postheparin plasma hepatic lipase and lipoprotein lipase. The method is a combination of m-aminophenylboronate and heparin-Sepharose affinity chromatographies. Hepatic lipase was purified to homogeneity as analyzed on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The specific activity of purified hepatic lipase was 5.46 mmol free fatty acids h−1 mg−1 protein with a total purification factor of 14 400 and a final recovery of approximately 20%. The recovery of hepatic lipase activity in m-aminophenylboronate affinity chromatography step was 95%. The purified lipoprotein lipase was a homogeneous protein with a specific activity of 8.27 mmol free fatty acids h−1 mg−1 The purification factor was 23 400 and the final recovery approximately 20%. The recovery of lipoprotein lipase activity in the m-aminophenylboronate affinity chromatography step was 87%. The phenylboronate affinity chromatography step can be used for purification of serine hydrolases which interact with boronates. 相似文献
6.
Kwang-Woo Lee Gab-Sang shin Hyun-Ae Bae Hyun-Dong shin Yong Hyun lee 《Biotechnology letters》2005,26(21):1639-1642
A new Acinetobacter sp. ES-1, grown on triolein, tryptone and Triton X-100, excreted a lipase that hydrolyzed 10m M (R,S)-ketoprofen ethyl ester into (S)-ketoprofen. The crude lipase had an activity of 10Uml-1 and, at 30°C and pH7 over 48h, gave a conversion yield of 35% with an enantiomeric excess for the product 96%. 相似文献
7.
The lipase Lip2 of the edible basidiomycete, Pleurotus sapidus, is an extracellular enzyme capable of hydrolysing xanthophyll esters with high efficiency. The gene encoding Lip2 was expressed
in Escherichia coli TOP10 using the gene III signal sequence to accumulate proteins in the periplasmatic space. The heterologous expression under
control of the araBAD promoter led to the high level production of recombinant protein, mainly as inclusion bodies, but partially
in a soluble and active form. A fusion with a C-terminal His tag was used for purification and immunochemical detection of
the target protein. This is the first example of a heterologous expression and periplasmatic accumulation of a catalytically
active lipase from a basidiomycete fungus. 相似文献
8.
The open reading frame AF1763, annotated as a putative lipase gene (lipA) of the
hyperthermophilic archaeon, Archaeoglobus fulgidus
DSM 4304, was cloned and over-expressed in E. coli.
A sequence analysis of LipA and the investigation of a truncated enzyme implied a special
function of the C-terminal part of LipA.
The substrate spectrum of the enzyme suggested that LipA is a carboxylesterase rather than a
canonical lipase. The enzyme showed optimal activity at 70 °C and between pH 10
and 11, which is among the most alkaline pH range detected for hydrolases. 相似文献
9.
Transpiration from excised leaves of Anthephra pubescens Nees was enhanced by 1 and 10 mmol m-3 kinetin. Stomatal opening in isolated epidermal strips of A. pubescens under CO2-free air and in the absence of K+ was enhanced by 10 mmol m-3 kinetin.Abbreviations ABA
abscisic acid 相似文献
10.
An intracellular lipase was induced inAspergillus flavipes grown on various triacylglycerols at pH 6.0 and at 30°C, with maximum activity with sunflower oil. The lipase had an optimum pH for activity of 8.8 and retained 30% of its activity at pH 10.0. It had an optimum temperature for activity, measured over 30 min, of 45°C. It was completely inactivated at 60°C within 10 min. 相似文献
11.
Candida rugosa lipase (EC 3.1.1.3) was used to degrade commercially-available solid poly(ester)urethane (Impranil) in an aqueous medium
under different temperature, pH, enzyme and substrate concentrations. A mathematical model was developed and applied to represent
the degradation kinetics of the solid polyurethane. Reaction optima were found to be pH 7 and 35°C. Diethylene glycol, a degradation
byproduct, generation rate was measured to be 0.12 mg/l min and the activation energy was calculated as 9.121 kcal/gmol K.
This information will be useful in developing bioreactors for practical applications to manage polyurethane wastes using lipase. 相似文献
12.
Rodolfo Quintana-Castro Pilar Díaz Gerardo Valerio-Alfaro Hugo S. García Rosamaría Oliart-Ros 《Molecular biotechnology》2009,42(1):75-83
The gene for a Geobacillus thermoleovorans CCR11 thermostable lipase was recovered by PCR and cloned. Four genetic constructions were designed and successfully expressed
in E. coli: (i) the lipase structural gene (lipCCR11) in the PinPoint Xa vector; (ii) the lipase structural gene (lipACCR11) in the pET-28a(+) vector; (iii) the lipase structural gene minus the signal peptide (lipMatCCR11) in the pET-3b vector; and (iv) the lipase structural gene plus its own promoter (lipProCCR11) in the pGEM-T cloning vector. The lipase gene sequence analysis showed an open reading frame of 1,212 nucleotides coding
for a mature lipase of 382 residues (40 kDa) plus a 22 residues signal peptide. Expression under T7 and T7lac promoter resulted in a 40- and 36-fold increase in lipolytic activity with respect to the original strain lipase. All recombinant
lipases showed an optimal activity at pH 9.0, but variations were found in the temperature for maximum activity and the substrate
specificity among them and when compared with the parental strain lipase, especially in the recombinant lipases that contained
fusion tags. Therefore, it is important to find the appropriate expression system able to attain a high concentration of the
recombinant lipase without compromising the proper folding of the protein. 相似文献
13.
Joo Ling Loo Oi Mlng Lai Kamariah Long Hasanah Mohd Ghazali 《World journal of microbiology & biotechnology》2007,23(12):1771-1778
Mycelium-bound lipase (MBL) was prepared using a strain of Geotrichum candidum isolated from local soil. At the time of maximum lipase activity (54 h), the mycelia to which the lipase was bound were harvested
by filtration and centrifugation. Dry MBL was prepared by lyophilizing the mycelia obtained. The yield of MBL was 3.66 g/l
with a protein content of 44.11 mg/g. The lipase activity and specific lipase activity were 22.59 and 510 U/g protein, respectively.
The moisture content of the MBL was 3.85%. The activity of free (extracellular) lipase in the culture supernatant (after removal
of mycelia) was less than 0.2 U/ml. The MBL showed selectivity for oleic acid over palmitic acid during hydrolysis of palm
olein, indicating that the lipase from G. candidum displayed high substrate selectivity for unsaturated fatty acid containing a cis-9 double bond, even in crude form. This unique specificity of MBL could be a direct, simple and inexpensive way in the fats
and oil industry for the selective hydrolysis or transesterification of cis-9 fatty acid residues in natural triacylglycerols. 相似文献
14.
Tamalampudi S Talukder MM Hama S Tanino T Suzuki Y Kondo A Fukuda H 《Applied microbiology and biotechnology》2007,75(2):387-395
To expand the industrial applications of Candida antarctica lipase B (CALB), we developed Aspergillus oryzae whole-cell biocatalyst expressing the lipase-encoding gene from C. antarctica. A. oryzae niaD300, which was derived from the wild type strain RIB40, was used as the host strain. The CALB gene was isolated from
C. antarctica CBS6678 and expression plasmids were constructed with and without secretion signal peptide. The lipase gene was expressed
under the control of improved glaA and pNo-8142 promoters of plasmids pNGA142 and pNAN8142, respectively. The Southern blot
analysis demonstrated the successful integration of the CALB gene in the genome of A. oryzae. To determine the role of signal peptide, the expression plasmids were constructed with homologous and heterologous secretion
signal sequences of triacylglycerol lipase gene (tglA) from A. oryzae and lipase B (CALB) from C. antarctica, respectively. The C-terminal FLAG tag does not alter the catalytic properties of the lipase enzyme and Western blotting
analysis using anti-FLAG antibodies demonstrated the presence of cell wall and membrane bound lipase responsible for the biocatalytic
activity of the whole-cell biocatalyst. The resultant recombinant A. oryzae was immobilized within biomass support particles (BSPs) made of polyurethane foam (PUF) and the BSPs were successfully used
for the hydrolysis of para-nitrophenol butyrate (p-NPB) and for the optical resolution of (RS)-1-phenyl ethanol by enantioselective transesterification with vinyl acetate as acyl donor. 相似文献
15.
The precipitation of N-cetylamine, N-cetylacetamide, hexadecane-1,2-diol, cetyl alcohol, and poly(butyl metacrylate) in acetone–water media in the presence of the lipase from Pseudomonas fluorescens was found to be accompanied by the coprecipitation of the enzyme. Within the lyophilized coprecipitates, the lipase exhibits a high catalytic activity and enantioselectivity in the reaction of (1RS)-phenylethanol acetylation with vinyl acetate in t-butyl methyl ether. In order of increasing lipase activity, the coprecipitates can be arranged in the series: cetyl alcohol, poly(butyl metacrylate), hexadecane-1,2-diol, N-cetylamine, and N-cetylacetamide, with the activity 2.5- to 19-fold exceeding the activity of the native enzyme. Immobilization of the lipase on solid supports, such as Celite 545 (physical sorption) and Eupergit C250L (covalent binding), in the presence of hexadecane-1,2-diol was found to increase the esterifying activity of the enzyme. 相似文献
16.
Esterification of m-cresol with acetic acid using porcine pancreas lipase (PPL) was investigated by response surface methodology (RSM). A central composite rotatable design (CCRD) involving 32 experiments of five variables at five levels was employed to analyse the esterification behaviour. The effect of five variables studied namely, m-cresol concentrations (0.005–0.025 mol), enzyme/substrate ratios (0.18–1.22 activity units/millimol, AU/mmol), incubation periods (6–54 h), pH (4–8) and buffer volumes (0–0.2 ml) was useful in arriving at an optimum ester yield. The methodology projected conditions for higher yields up to 6.0 mmol. Validation experiments carried out under these predicated conditions showed good correspondence between experimental and predicted yields. CCRD treatment clearly showed the inhibitory nature of m-cresol in the esterification process. The reaction required the presence of buffer for better conversions and a minimum amount of 0.1 ml buffer was found necessary for this reaction. Buffer pH values around 6.0 and below appeared to favour better esterification than those at pH values in the range 6.0–8.0. However an optimum condition for maximum yield was: incubation period: 54 h; buffer volume: 0.2 ml; pH: 8; E/S ratio: 0.83 AU/mmol; m-cresol: 0.02 mol; predicted yield: 6.0 mmol; experimental yield: 6.4 mmol. 相似文献
17.
Most probable number (MPN) estimates indicated that a mean of 4.3×107 and 5×106 bacteria per ml of rumen fluid from a predominantly alfalfa hay-fed steer demethoxylated ferulate and syringate, respectively. After further enrichment from an MPN tube of the highest dilution showing demethoxylation of syringate, strain S195 was isolated using roll tubes with syringate as an added energy source. S195 was an anaerobic, Gram-negative, nonmotile coccus, 1 to 1.3 m in diameter, and was unique in using various carbohydrates as electron donor with acetate as the sole organic product. One of the following electron acceptor systems allowed growth (organic products in parentheses): Methanobrevibacter simithii (CH4), formate (acetate), 3,4,5-trimethoxybenzoate and syringate (acetate and gallate), vanillate (acetate and protocatechuate), vanillin (acetate, protocatechuic aldehyde and protocatechuate), ferulate (acetate, caffeate and hydrocaffeate), caffeate (hydrocaffeate). Strain S195 required 30% (v/v) rumen fluid in the medium for good growth. S195 was placed in a new genus and species, Syntrophococcus sucromutans, of the family Veillonellaceae.Abbreviations G+C
Guanine plus cytosine
- MPN
most probable number
- OD
optical density 相似文献
18.
Propan-2-ol was used as an acyl acceptor for immobilized lipase-catalyzed preparation of biodiesel. The optimum conditions
for transesterification of crude jatropha (Jatropha curcas), karanj (Pongamia pinnata) and sunflower (Helianthus annuus) oils were 10% Novozym-435 (immobilized Candida antarctica lipase B) based on oil weight, alcohol to oil molar ratio of 4:1 at 50 °C for 8 h. The maximum conversions achieved using
propan-2-ol were 92.8, 91.7 and 93.4% from crude jatropha, karanj and sunflower oils, respectively. Reusability of the lipase
was maintained over 12 repeated cycles with propan-2-ol while it reached to zero by 7th cycle when methanol was used as an acyl acceptor, under standard reaction conditions.
Revisions requested 22 December 2005; Revisions received 26 January 2006 相似文献
19.
Masahiro Mori Ehsan Ali Dongning Du Enoch Y. Park 《Biotechnology and Bioprocess Engineering》2009,14(2):193-201
The aim of this study was to improve the production of an extracellular alkaline lipase from Alcaligenes sp. (ATCC 31371) by optimization of the culture medium, for economic production of biodiesel from waste vegetable oil. A
number of carbon sources including different types of starch, sugar, sugar alcohol, organic acids, and surfactants were investigated.
Polyoxyethylene (20) sorbitan tristearate, whose side chain is stearic acid, was the most effective carbon source for lipase
production. Box-Behnken experimental design was used for three factors (soy protein, sodium nitrate, and stearic acid) and
the optimal composition for maximum lipase production (1.7-fold enhancement) was established as soy protein 4.07%, sodium
nitrate 0.17%, and stearic acid 0.28% at 28°C with an agitation rate of 220 rpm for 24 h. The enzyme was purified to homogeneity
and the recovery of the lipase activity was 7.8% with a 30-fold purification. The estimated molecular size of the protein
determined by SDS-PAGE was 33 kDa. The optimum pH and temperature of the purified lipase was 8.5 and 40°C, respectively. The
purified enzyme was stable in the pH range of 6.0 and 9.5 and in the temperature range of 20 and 50°C. 相似文献
20.
A spectrophotometric assay has been adapted to directly measure the activity of enzymes immobilised on insoluble magnetic
particles. Three different types of lipases (Candida antarctica lipase A and B and Thermocatenulatus lanuginosus lipase) were immobilised on two types of magnetic beads. The activity of the resulting immobilised lipase preparations was
measured directly in the reaction solution by using a modified p-nitrophenol ester assay using a spectrophotometer. Removal of the solid particles was not necessary prior to spectrophotometric
measurement, thus allowing reliable kinetic measurements to be made rapidly. The method was effective for a wide range of
magnetic bead concentrations (0.01–0.2 mg ml−1). In all cases the assay could determine the bead-related specific enzyme activity. The assay was validated by comparing
with a pH-stat method using p-nitrophenol palmitate as the substrate with an excellent correlation between the two methods. The utility of the spectrophotometric
assay was demonstrated by applying it to identify the best combination of lipase type, activation chemistry and magnetic particle.
Epoxy activation of poly vinyl alcohol-coated magnetic particles prior to immobilisation of commercial C. antarctica lipase A gave the best preparation. 相似文献