共查询到20条相似文献,搜索用时 31 毫秒
1.
M. C. B. Pimentel N. Krieger L. C. C. B. Coelho J. O. Fontana E. H. M. Melo W. M. Ledingham J. L. Lima Filho 《Applied biochemistry and biotechnology》1994,49(1):59-74
A lipases (glycerol ester hydrolases E. C. 3.1.1.3) from a brazilian strain ofPenicillium citrinum has been investigated. When the microorganism was cultured in the simple medium (1.0% olive oil and 0.5% yeast extract),
using olive oil in as carbon source in the inocula, the enzyme extracted showed maximum activity (409 IU/mL). In addition,
decrease of yeast extract concentration also reduces the lipase activity. Nevertheless, when yeast extract was replaced by
ammonium sulfate, no activity was detected. Purification by precipitation with ammonium sulfate showed best activity in the
40–60% fraction. The optimum temperature for enzyme activity was found in the range of 34–37°C. However, after 30 min at 60°C,
the enzyme was completely inactivated. The enzyme showed optimum at pH 8.0. The dried concentrated fraction (after dialysis
and lyophilization) maintained its lipase activity at room temperature (28°C) for 8 mo. This result in lipase stability suggests
an application of lipases fromP. citrinum in detergents and other products that require a high stability at room temperature. 相似文献
2.
Palma Marcia B. Pinto Annette L. Gombert Andreas K. Seitz Karina H. Kivatinitz Silvia C. Castilho Leda R. Freire Denise M. G. 《Applied biochemistry and biotechnology》2000,84(1-9):1137-1145
Lipase, protease, and amylase production by Penicillium restrictum in solid-state fermentation was investigated. The basal medium was an industrial waste of babassu oil (Orbignya oleifera) production. It was enriched with peptone, oliveoil, and Tween-80. The supplementation positively influenced both enzyme
production and fungal growth. Media enriched with Tween-80 provided the highest protease activity (8.6 U/g), whereas those
enriched with peptone and olive oil led to the highest lipase (27.8 U/g) and amylase (31.8 U/g) activities, respectively. 相似文献
3.
Freire Denise M. Teles Elaine M. F. Bon Elba P. S. Anna Geraldo Lippel Sant’ 《Applied biochemistry and biotechnology》1997,(1):409-421
A preliminary screening work selectedPenicillium restrictum as a promising micro-organism for lipase production. The physiological response of the fungus towards cell growth and enzyme
production upon variable carbon and nitrogen nutrition, specific air flow rate (Qa) and agitation (N) was evaluated in a 5-L
bench-scale fermenter. In optimized conditions for lipase production meat peptone at 2% (w/v) and olive oil at 1% (w/v) were
used in a growth medium with a C/N ratio of 9.9. Higher C/N ratios favored cell growth in detriment of enzyme production.
Low extracellular lipase activities were observed using glucose as carbon source suggesting glucose regulation. Final lipase
accumulation of 13,000 U/L was obtained, using optimized specific air flow rate (Qa) of 0.5 wm and an impeller speed (N) of
200 rpm. Agitation showed to be an important parameter to ensure nutrient availability in a growth medium having olive oil
as carbon source. 相似文献
4.
Melissa L. E. Gutarra Elisa D. C. Cavalcanti Leda R. Castilho Denise M. G. Freire Geraldo L. Sant’Anna Jr. 《Applied biochemistry and biotechnology》2005,121(1-3):105-116
The production of lipase by Penicillium simplicissimum in solid-state fermentation was studied using babassu cake as the basal medium. Tray-type and packed-bed bioreactors were employed. In the former, the influence of temperature; content of the medium, and medium supplementation with olive oil, sugarcane molasses, corn steep liquor, and yeast hydrolysate was studied. For all combinations of supplements, a temperature of 30°C, a moisture content of 70%, and a concentration of carbon source of 6.25% (m/m, dry basis) provided optimum conditions for lipase production. When used as single supplements olive oil and molasses also were able to provide high lipase activities (20 U/g). Using packed-bed bioreactors and molasses-supplemented medium, optimum conditions for enzyme production were air superficial velocities above 55 cm/min and temperatures below 28°C. The lower temperature optimum found for these reactors is probably related to radial heat gradient formation inside the packed bed. Maximum lipase activities obtained in these bioreactors (26.4 U/g) were 30% higher than in tray-type reactors. 相似文献
5.
Roberto Nobuyuki Maeda Mariana Mello Pereira da Silva Lídia Maria Melo Santa Anna Nei Pereira Jr. 《Applied biochemistry and biotechnology》2010,161(1-8):411-422
The present study aimed at maximizing cellulase production by Penicillium funiculosum using sequential experimental design methodology for optimizing the concentrations of nitrogen sources. Three sequential experimental designs were performed. The first and the second series of experiments consisted of a 24 and a 23 factorial designs, respectively, and in the third one, a central composite rotational design was used for better visualizing the optimum conditions. The following nitrogen sources were evaluated: urea, ammonium sulfate, peptone, and yeast extract. Peptone and ammonium sulfate were removed from the medium optimization since they did not present significant statistical effect on cellulase production. The optimal concentrations of urea and yeast extract predicted by the model were 0.97 and 0.36 g/L, respectively, which were validated experimentally. By the use of the desirability function, it was possible to maximize the three main enzyme activities simultaneously, which resulted in values for FPase of 227 U/L, for CMCase of 6,917 U/L, and for β-glucosidase of 1,375 U/L. These values corresponded to increases of 3.3-, 3.2-, and 6.7-folds, respectively, when compared to those obtained in the first experimental design. The results showed that the use of sequential experimental designs associated to the use of the desirability function can be used satisfactorily to maximize cellulase production by P. funiculosum. 相似文献
6.
Silva MF Freire DM de Castro AM Di Luccio M Mazutti MA Oliveira JV Treichel H de Oliveira D 《Applied biochemistry and biotechnology》2011,164(6):755-766
One relevant limitation hindering the industrial application of microbial lipases has been attributed to their production
cost, which is determined by the production yield, enzyme stability among other. The objective of this work was to evaluate
the concentration and immobilization of lipase extracts from Penicillium brevicompactum obtained by solid-state fermentation of babassu cake and castor bean cake. The precipitation with ammonium sulfate 60% of
saturation of crude extract obtained with babassu cake as raw material showed an enhancement in hydrolytic and esterification
activities from 31.82 to 227.57 U/g and from 170.92 to 207.40 U/g, respectively. Concentrated lipase extracts showed preference
to medium-chain triglycerides and fatty acids. It is shown that the enzyme activity is maintained during storage at low temperatures
(4 and −10°C) for up to 30 days. Higher esterification activities were achieved when the lipase extract was immobilized in
sodium alginate and activated coal. 相似文献
7.
Summary An extracellular lipase was produced by Bacillus coagulans by solid-state fermentation. Solid waste from melon was used as the basic nutrient source and was supplemented with olive
oil. The highest lipase production (78,069 U/g) was achieved after 24h of cultivation with 1% olive oil enrichment. Enzyme
had an optimal activity at 37°C and pH 7.0, and sodium dodecyl sulfate increased lipase activity. NH 4NO3 increased enzyme production, whereas organic nitrogen had no effect. The effect of the type of carbon sources on lipolytic
enzyme production was also studied. The best results were obtained with starch and maltose (148,932 and 141,629 U/g, respectively),
whereas a rather low enzyme activity was found in cultures grown on glucose and galactose (approx 118,769 and 123,622 U/g,
respectively). Enzyme was inhibited with Mn+2 and Ni+2 by 68 and 74%, respectively. By contrast, Ca+2 enhanced enzyme production by 5%. 相似文献
8.
Eltayib Hassan Ahmed Tripti Raghavendra Datta Madamwar 《Applied biochemistry and biotechnology》2010,160(7):2102-2113
A mesophilic bacterial culture producing a novel thermostable alkaline lipase was isolated from oil rich soil sample and identified
as Bacillus subtilis EH 37. The lipase was partially purified by ammonium sulfate precipitation and hydrophobic interaction chromatography with
17.8-fold purification and 41.9 U/ml specific activity. The partially purified enzyme exhibited maximum activity at pH 8.0
and at 60 °C. It retained 100% of activity at 50 °C and 60 °C for 60 min. The presence of Ca+2, Mg+2, and Zn2+ exhibited stimulatory effect on lipase activity, whereas Fe+3 and Co+2 reduced its activity. The enzyme retained more than 80% of its initial activity upon exposure to organic solvents, exhibited
107% and 115% activity in the presence of 15% isopropyl alcohol and 30% n-hexane, respectively. The EH 37 lipase also proved
to be an efficient catalyst in synthesis of ethyl caprylate in organic solvent, thus providing a concept of application of
B. subtilis lipase in non-aqueous catalysis. 相似文献
9.
Optimization of inulinase production by Kluyveromyces marxianus using factorial design 总被引:4,自引:0,他引:4
Factorial design and response surface techniques were used to optimize the culture medium for the production of inulinase
by Kluyveromyces marxianus. Sucrose was used as the carbon source instead of inulin. Initially, a fractional factorial design (25–1) was used in order to determine the most relevant variables for enzyme production. Five parameters were studied (sucrose,
peptone, yeast extract, pH, and K2HPO4), and all were shown to be significant. Sucrose concentration and pH had negative effects on inulinase production, whereas
peptone, yeast extract, and K2HPO4 had positive ones. The pH was shown to be the most significant variable and should be preferentially maintained at 3.5. According
to the results from the first factorial design, sucrose, peptone, and yeast extract concentrations were selected to be utilized
in a full factorial design. The optimum conditions for a higher enzymatic activity were then determined: 14 g/L of sucrose,
10 g/L of yeast extract, 20 g/L of peptone, 1 g/L of K2HPO4. The enzymatic activity in the culture conditions was 127 U/mL, about six times higher than before the optimization. 相似文献
10.
Emilia Curotto Marisol Concha Victoriano Campos Adriane M. F. Milagres Nelson Duran 《Applied biochemistry and biotechnology》1994,48(2):107-116
Xylanase production byPenicillium janthinellum using 10–100 mM of 2,2-dimethylsuccinate (DMS) buffer, in a range of pH 4.5-6.0 was studied. The enzyme activity was enhanced
using oat xylan as the carbon source. Under these conditions a culture produced 1.14 Μmol/ min (11.4 U/mL or 84.4 U/mg) of
Β-xylanase after 5 d of growth in a 10-mM buffer solution at pH 4.5. Protease was absent in the DMS buffer except when 100
mM phosphate buffer at pH 6.0 was used (4 U/mL). Β-Xylosidase was only found at a pH of 4.5 in all the buffer concentrations.
At a 50 mM DMS buffer concentration at pH 4.5 Β- xylanases were induced by both oat and birch xylans, having a greater effect with oat spelt xylans.
Electrophoretic analyses showed that the birchwood xylan induction exhibited different proteins profiles. No Β-xylosidase
or Β- glucosidase was induced until d 5. The Β-xylanases were rapidly inactivated at 50‡C, however, birch xylanase appeared to
be more stable than oat xylanase.
Using oat xylan as an inductor, theΒ-xylosidase andΒ-glucosidase were 85 and 91 U/L, respectively, on d 7. The xylanase produced by induction from sugar cane bagasse hydrolyzate
was used for pulp biobleaching. A 20% decrease on the Kappa value in Kraft pulp using the culture extract was obtained. These
selective growth conditions led us to modulate the xylanase production for pulp delignification. 相似文献
11.
N. Krieger M. A. Taipa E. H. M. Melo J. L. Lima-Filho M. R. Aires-Barros J. M. S. Cabral 《Applied biochemistry and biotechnology》1997,67(1-2):87-95
A lipase from a wild strain ofPenicillium citrinum was encapsulated in AOT/isooctane-reversed micelles, and the kinetic parameters were studied relative to triolein hydrolysis. Lipolytic activity was strongly dependent on the water amount in the system (Wo) and presented a bell-shaped curve for this parameter, with a maximum in the range of Wo 10–15. Optimum conditions for enzyme activity were pH 8.0 and 45?C. The influence of substrate concentration was also studied. The enzyme showed a Michaelis-Menten behavior and the apparent kinetics constants were calculated as beingV max.app. - 120 U/mg and Kmapp = 49.2 mM. 相似文献
12.
《印度化学会志》2021,98(10):100143
Lipases are ubiquitous enzymes that belong to family of serine hydolases with a wide variety of industrial applications. This study reports isolation, screening and identification of enantioselctive lipase producing microorganism for kinetic resolution of racemic alcohols. For this, we collected soil samples from different oil rich environments and we performed primary screening that was by carried out by using MSM-tributryin clear zone assay. The selected samples from first screen were subjected to secondary screening to distinguish lipase producing strains from esterase producing strains using p-nitrophenyl palmitate lipase assay. In tertiary screening, 16 lipase producing strains that were identified in secondary screening were employed for resolution of 5 different (RS)-alcohols. Out of all 16 lipase producing strains, only one strain selectively converted 3 racemic alcohols. Based on morphological, biochemical and physiological characteristics, and 16S rRNA gene sequencing, the strain was identified as Pseudomonas beteli. The strain was found to be S-selective and there been no reports on use of Pseudomonas beteli lipase for kinetic resolution of alcohols. The lipase activity was further increased by media optimization and by improving growth conditions, and production of lipase in shake flask study as well as in laboratory scale fermenter. The optimum time for enzyme production by Pseudomonas beteli was 96 h whereas cell mass growth was highest at 72 h. Optimum temperature and pH were 30 °C and 6, respectively. Beef extract (5 g/L), peptone (5 g/L), sodium chloride (5 g/L), yeast extract (1 g/L) and glucose (5 g/L) were found as optimum nutrition sources for the cell mass growth and lipase production by Pseudomonas sp. Overall, 3.4 times higher enzyme activity and 2.75 times higher cell mass growth were achieved in bioreactor in comparison to the shake flask study. Lipase having high titer was employed successfully for the kinetic resolution of several drug intermediates. 相似文献
13.
Yiqun Chen Bo Zhang Honglei Pei Junnan Lv Wenhan Yang Yunhe Cao Bing Dong 《Applied biochemistry and biotechnology》2012,168(3):638-650
In this study, the activity of an ??-galactosidase obtained from Penicillium janczewskii zalesk was improved via modifying its gene by error-prone PCR and DNA shuffling. The mutated DNA was ligated to pBGP1, an autonomous-replicating vector, which was subsequently transformed into Pichia pastoris X-33. The expressed enzyme activities were measured after single colonies were cultured in yeast?Cpeptone?Cdextrose medium in deep-well plates. After two rounds of screening, two mutants with higher activity were obtained. By PCR analysis, four mutation sites (S167G, P455L, N637S, and P490L/P490H) were found in these two variants (mutant-59 and mutant-8). Mutant-59 showed the highest activity at pH?5.0 and 40?°C with an increased V max value of 769???mol/min and the specific activity of 667?U/mg against p-nitrophenyl ??-D-galactopyranoside. The two mutant enzymes also showed similar resistance to the metal ions of Cu2+, Fe2+, and Zn2+. In a 10-L fermenter, the supernatant enzyme activity reached the maximum of 550.2?U/mL upon the methanol induction for 96?h. This fermentation activity of the mutant was improved approximately two more folds than the wild type ??-galactosidase. This mutant of ??-galactosidase is prospective in feed manufacturing as feed additives to improve nutrient digestibility in monogastric animals. 相似文献
14.
Studies on lipase production and characterization were carried out with a bacterial strain Staphylococcus arlettae JPBW-1 isolated from rock salt mine, Darang, HP, India. Higher lipase activity has been obtained using 10 % inoculum with 5 % of soybean oil as carbon source utilizing a pH 8.0 in 3 h at 35 °C and 100 rpm through submerged fermentation. Partially purified S. arlettae lipase has been found to be active over a broad range of temperature (30–90 °C), pH (7.0–12.0) and NaCl concentration (0–20 %). It has shown extreme stability with solvents such as benzene, xylene, n-hexane, methanol, ethanol and toluene up to 30 % (v/v). The lipase activity has been found to be inhibited by metal ions of K+, Co2+ and Fe 2+ and stimulated by Mn2+, Ca2+ and Hg2+. Lipase activity has been diminished with denaturants, but enhanced effect has been observed with surfactants, such as Tween 80, Tween 40 and chelator EDTA. The K m and V max values were found to be 7.05 mM and 2.67 mmol/min, respectively. Thus, the lipase from S. arlettae may have considerable potential for industrial application from the perspectives of its tolerance towards industrial extreme conditions of pH, temperature, salt and solvent. 相似文献
15.
Pulsed Laser‐Driven Molecular Self‐assembly of Cephalexin: Aggregation‐Induced Fluorescence and Its Utility as a Mercury Ion Sensor 下载免费PDF全文
Pradeep Kumar Singh Asmita Prabhune Satishchandra Ogale 《Photochemistry and photobiology》2015,91(6):1340-1347
A fluorescent self‐assembly of cephalexin is obtained by pulsed laser irradiation process. An intense fluorescence emission is found in the self‐assembled form due to occurrence of a typical aggregation‐induced emission in cephalexin molecules. It is observed that fluorescence quenching of the self‐assembled fluorescent nanostructures occurs in the presence of extremely low Hg++ ions concentrations (10?7 m ) as compared to other heavy metal ions e.g. Ferrous (Fe++), Manganese (Mn++), Magnesium (Mg++), Cobalt (Co++), Nickel (Ni++) and Zinc (Zn++) at the same concentrations. 相似文献
16.
Marco di Luccio Fernando Capra Najara P. Ribeiro Gean D. L. P. Vargas Denise M. G. Freire Débora de Oliveira 《Applied biochemistry and biotechnology》2004,113(1-3):173-180
The production of lipases by Penicillium simplicissimum using solid-state fermentation and soy cake as substrate was investigated. The effects of temperature, cake moisture, and
carbon supplementation on lipase production were studied using a two-level experimental plan. Moisture, pH, and lipase activity
were followed during fermentation. Statistical analysis of the results was performed to evaluate the effect of the studied
variables on the maximum lipase activity. Incubation temperature was the variable that most affected enzyme activity, showing
a negative effect. Moisture and carbon supplementation presented a positive effect on activity. It was possible to obtain
lipase activity as high as 21 U/g of dry cake in the studied range of process variables. 相似文献
17.
Production of an extracellular lipase from Serratia marcescens ECU1010, which is an industrially important biocatalyst for the stereospecific synthesis of Diltiazem precusor, was carefully
optimized in both shake flasks and a fermenter, using Tween-80 as the enzyme inducer. Dextrin and beef extract combined with
ammonium sulfate were indicated to be the best carbon and nitrogen sources, respectively. With the increase of Tween-80 from
0 to 10 g l−1, the lipase production was greatly enhanced from merely 250 U l−1 to a maximum of 3,340 U l−1, giving the highest lipase yield of ca 640 U g−1 dry cell mass (DCW), although the maximum biomass (6.0 g DCW l−1) was achieved at 15 g l−1 of Tween-80. When the medium loading in shake flasks was reduced from 20 to 10% (v / v), the lipase production was significantly enhanced. The increase in shaking speed also resulted in an improvement of the
lipase production, although the cell growth was slightly repressed, suggesting that the increase of dissolved oxygen (DO)
concentration contributed to the enhancements of lipase yield. When the lipase fermentation was carried out in a 5-l fermenter,
the lipase production reached a new maximum of 11,060 U l−1 by simply raising the aeration rate from 0.5 to 1.0 vvm, while keeping the dissolved oxygen above 20% saturation via intermittent
adjustment of the agitation speed (≥400 rpm), in the presence of a relatively low concentration (2 g l−1) of Tween-80 to prevent a potential foaming problem, which is easy to occur in the intensively aerated fermenter. 相似文献
18.
Fungal isolates (Aspergillus wentii 1, A. wentii 2, Penicillium citrinum, Penicillium granulatum) were selected to study their in vitro antioxidant potential by various assay procedures. Czapek–Dox’s medium was selected
for the growth of fungi as it supported the best antioxidant activity based on their EC50 values, P. citrinum was the best followed by P. granulatum, A. wentii 1, and A. wentii 2. The chromatographic analyses showed several compounds possessing antioxidant activity in the fungal extracts. Two such
compounds were partially purified from P. citrinum which demonstrated potent antioxidant activity, equally effective or better than some of the standard antioxidants. 相似文献
19.
Alkaline lipase production byAcinetobacter radioresistens was performed in a batch fill- and-draw culture, and the results were compared with a batch culture. In the batch culture,
the lipase yield was 18 U/mL, which was restricted by the occurrence of protease forming and excessive foaming as cell growth
ceased. Because the formation of lipase was found to be chiefly growth-associated, the fill- and-draw culture, which provided
an environment for continuous growth, could surpass the limitation encountered in a batch culture and increase the lipase
yield to 30 U/mL. The improvement in the lipase yield was suggested to be caused by an adaptation of the cells to the medium
during the repeated culture. Although the increase in the lipase yield was accompanied by a decrease in lipase productivity,
the fill- and-draw culture could be a better mode for lipase production. 相似文献
20.
Moftah OA Grbavčić S Zuža M Luković N Bezbradica D Knežević-Jugović Z 《Applied biochemistry and biotechnology》2012,166(2):348-364
Olive oil cake is a by-product from the olive oil processing industry and can be used for the lipase and protease production
by Candida utilis in solid state fermentation. Different carbon and nitrogen sources were evaluated, and the results showed that the supplementation
of the substrate with maltose and starch as carbon sources and yeast extract as a nitrogen source significantly increased
the lipase production. The best results were obtained with maltose, whereas rather low lipase and protease activities were
found with glucose and oleic acid. Response surface methodology and a five-level–three-factor central composite rotatable
design were used to evaluate the effects of the initial moisture content, inoculum size and fermentation time on both lipase
and protease activity levels. A lipase activity value of ≈25 U g-1 and a protease activity value of 110 U g-1 were obtained under the optimized fermentation conditions. An alkaline treatment of the substrate appeared to be efficient,
leading to increases of 39% and 133% in the lipase and protease production, respectively. The results showed that the olive
cake could be a good source for enzyme production by solid state fermentation. 相似文献