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1.
Thermomucor indicae-seudaticae was immobilized in alginate, κ-carrageenan, agarose, agar, polyacrylamide and loofah (Luffa cylindrica) sponge (as such or coated with alginate/starch/Emerson YpSs agar), and used for the production of glucoamylase in submerged
fermentation. The mycelium developed from alginate-immobilized sporangiospores secreted higher glucoamylase titres (22.7 U ml−1) than those immobilized in other gel matrices and the freely growing mycelial pellets (18.5 U ml−1). Loofah network provided a good support for mycelial growth, but the enzyme production was lower than that attained with
alginate beads. Glucoamylase production increased with inoculum density and the optimum levels were achieved when 40 calcium
alginate beads (∼5 × 106 immobilized spores) were used to inoculate 50 ml production medium. The alginate bead inoculum displayed high storage stability
at 4°C and produced comparable enzyme titres up to 120 days. The glucoamylase production by hyphae emerged from the immobilized
sporangiospores was almost stable over eight batches of repeated fermentation. Scanning electron micrographs of alginate beads,
after batch fermentation, revealed extensive mycelial growth inside and around the beads. 相似文献
2.
A Bacillus sp., capable of degrading chloroform, was immobilized in calcium alginate. The beads in 20 g alginate l−1 (about 2 × 108 cells/bead) could be re-used nine times for degradation of chloroform at 40 μM. The immobilized cells had a higher range
of tolerance (pH 6.5–9 and 20–41°C) than free cells (pH 7–8.5 and 28–32°C). At 5 g alginate l−1, leakage of the cells from the beads was 0.51 mg dry wt ml−1. This species is the first reported Bacillus that can degrade chloroform as the sole carbon source. 相似文献
3.
Fine, almost single cell, suspensions were produced from both existing suspension cultures containing large cell clumps and
from chopped callus pieces by immobilizing the cells in 4–5 mm diameter calcium alginate beads. The immobilized cells continued
to divide inside the beads and at the bead surface, and after 2–3 weeks' culture, fine cell suspensions were formed as a result
of loss of the surface cells into the medium. After removal of the cell suspensions by filtration, subsequent culture of the
beads in fresh medium resulted in the further production of homogeneous cell suspensions after 1–2 weeks. In this way an almost
continuous supply of fine cell suspensions could be obtained from cultures containing large clumps of cells. The cells produced
by this method remained in this state for at least one culture period, although in some instances repeated subculture resulted
in an increase in the size of cell groups. The technique has been successfully applied to the production of fine cell suspensions
ofCatharanthus roseus, Nicotiana tabacum andDaucus carota. 相似文献
4.
Sirisansaneeyakul S Luangpipat T Vanichsriratana W Srinophakun T Chen HH Chisti Y 《Journal of industrial microbiology & biotechnology》2007,34(5):381-391
Production of lactic acid from glucose by immobilized cells of Lactococcus lactis IO-1 was investigated using cells that had been immobilized by either entrapment in beads of alginate or encapsulation in
microcapsules of alginate membrane. The fermentation process was optimized in shake flasks using the Taguchi method and then
further assessed in a production bioreactor. The bioreactor consisted of a packed bed of immobilized cells and its operation
involved recycling of the broth through the bed. Both batch and continuous modes of operation of the reactor were investigated.
Microencapsulation proved to be the better method of immobilization. For microencapsulated cells at immobilized cell concentration
of 5.3 g l−1, the optimal production medium had the following initial concentrations of nutrients (g l−1): glucose 45, yeast extract 10, beef extract 10, peptone 7.5 and calcium chloride 10 at an initial pH of 6.85. Under these
conditions, at 37 °C, the volumetric productivity of lactic acid in shake flasks was 1.8 g l−1 h−1. Use of a packed bed of encapsulated cells with recycle of the broth through the bed, increased the volumetric productivity
to 4.5 g l−1 h−1. The packed bed could be used in repeated batch runs to produce lactic acid. 相似文献
5.
Bioconversion of (4R)-(+)-limonene to (4R)-(+)-α-terpineol by immobilized fungal mycelia of Penicillium digitatum was investigated in batch, repeated-batch and continuously fed systems. The fungi were immobilized in calcium alginate beads.
These beads remained active for at least 14 days when they were stored at 4 °C. Three different aeration rates were tested.
The highest yield was obtained at a dissolved oxygen level of 50.0 μmol/l. α-Terpineol production by this fungus was 12.83 mg
(g beads)−1 day−1, producing a 45.81% bioconversion of substrate. Repeated-batch bioconversion showed yield decreases in the second and the
third cycles. Regeneration with nutrient media after the third cycle improved the bioconversion yields. With continuous bioconversion,
the half-life was dependent on the aeration. The optimum conditions with a continuous reactor were at an aeration rate of
0.3 standard l/min and a dilution rate of 0.0144 h−1.
Received: 10 June 1997 / Received revision: 18 August 1997 / Accepted: 11 September 1997 相似文献
6.
Kar S Mandal A Mohapatra PK Samanta S Pati BR Mondal KC 《Journal of industrial microbiology & biotechnology》2008,35(4):245-249
In the present study, the optimum conditions for the production of xylanase by immobilized spores of Trichoderma reesei SAF3 in calcium alginate beads were determined. The operational stability of the beads during xylanase production under semi-continuous
fermentation was also studied. The influence of alginate concentration (1, 2, 3, and 4%) and initial cell loading (100, 200,
300, 400, and 500 beads per flask) on xylanase production was considered. The production of xylanase was found to increase
significantly with increasing concentration of alginate and reached a maximum yield of 3.12 ± 0.18 U ml−1 at 2% (w/v). The immobilized cells produced xylanase consistently up to 10 cycles and reached a maximum level at the forth
cycle (3.36 ± 0.2 U ml−1). 相似文献
7.
A. S. Abdel-Razek T. M. Abdel-Ghany S. A. Mahmoud H. H. El-Sheikh M. S. Mahmoud 《World journal of microbiology & biotechnology》2009,25(12):2137-2145
This paper discusses the possible application to use free and immobilized Cunninghamella elegans for the removal of cobalt from aqueous waste solutions. Results indicated that the maximum uptake occurred at; pH 4.0–5.5 ± 0.2,
temperature range between 15 and 50°C and stirring rate 250 rpm. The uptake increased with the increase of metal ion concentration
up to 40 ppm. Also, it was found that the best biomass weights used for biosorption were 0.25 and 0.5 g for both free and
immobilized biomass. The reuse of control alginate beads, alive and dead immobilized Cunninghamella elegans beads was investigated for five cycles. Results showed that the percent uptake decreased slightly after the first cycle.
While, in the case of alginate beads there was increase in the second cycle then returned to the same level of uptake. The
uptake of cobalt in the presence of Cr(VI) and Cd(II) at different mixture concentrations 40, 50 and 60 ppm was investigated.
The results showed that the uptake amount of Co(II) in the presence of other metal ions was lower than Co(II) alone except
for Ca-alginate beads. SEM studies for control alginate beads, alive and dead immobilized Cunninghamella elegans beads were conducted to investigate the beads before and after the accumulation of cobalt ions. 相似文献
8.
Sareeta Nahakpam Puneeta Singh Kavita Shah 《Biotechnology and Bioprocess Engineering》2008,13(5):632-638
The direct immobilization of soluble peroxidase isolated and partially purified from shoots of rice seedlings in calcium alginate
beads and in calcium agarose gel was carried out. Peroxidase was assayed for guaiacol oxidation products in presence of hydrogen
peroxide. The maximum specific activity and immobilization yield of the calcium agarose immobilized peroxidase reached 2,200
U mg−1 protein (540 mU cm−3 gel) and 82%, respectively. In calcium alginate the maximum activity of peroxidase upon immobilization was 210 mU g−1 bead with 46% yield. The optimal pH for agarose immobilized peroxidase was 7.0 which differed from the pH 6.0 for soluble
peroxidase. The optimum temperature for the agarose immobilized peroxidase however was 30°C, which was similar to that of
soluble peroxidase. The thermal stability of calcium agarose immobilized peroxidase significantly enhanced over a temperature
range of 30∼60°C upon immobilization. The operational stability of peroxidase was examined with repeated hydrogen peroxide
oxidation at varying time intervals. Based on 50% conversion of hydrogen peroxide and four times reuse of immobilized gel,
the specific degradation of guaiacol for the agarose immobilized peroxidase increased three folds compared to that of soluble
peroxidase. Nearly 165% increase in the enzyme protein binding to agarose in presence of calcium was noted. The results suggest
that the presence of calcium, ions help in the immobilization process of peroxidase from rice shoots and mediates the direct
binding of the enzyme to the agarose gel and that agarose seems to be a better immobilization matrix for peroxidase compared
to sodium alginate. 相似文献
9.
José Edmundo Nava Saucedo Jean-Noël Barbotin Daniel Thomas 《Applied microbiology and biotechnology》1989,30(3):226-233
Summary The continuous production of gibberellic acid with immobilized mycelia of Gibberella fujikuroi was maintained over a hundred days in a tubular fixed-bed reactor. Free mycelium at the beginning of the storage phase was harvested from G. fujikuroi shake-flask culture and was immobilized by ionotropic gelation in calcium alginate beads.The continuous recycle production system consisted of a fixed-bed reactor, a container in which the culture medium was heated, stirred and aerated, and valves for sample withdrawal or reactant addition during the first 1320 h (55 days). A two-phase continuous extractor was then added for the last 960 hours (40 days). Free and immobilized mycelium shake-flask cultures with the same strain used in the continuous culture system were also realized to compare growth, maintenance and production parameters. The results show about the same gibberellic acid productivity in both free and immobilized mycelium shakeflask cultures: 0.384 and 0.408 mgGA3·gBiomass-1 ·day-1, respectively, whereas in the continuous system the gibberellic acid production is about twice as large for a similar biomass: 0.768 mgGA3·gBiomass-1·day-1. Several factors affecting the overall productivity of the immobilized systems were found to be: the quality and the quantity of mycelia in the biocatalyst beads and the immobilization conditions. 相似文献
10.
M. Kudlich P. L. Bishop H.-J. Knackmuss A. Stolz 《Applied microbiology and biotechnology》1996,46(5-6):597-603
The naphthalenesulfonate-oxidizing bacterium Sphingomonas sp. BN6 was immobilized in calcium alginate. These beads were incubated under aerobic conditions in a medium with the sulfonated
azo dye, Mordant Yellow 3 (MY3), and glucose. The immobilized cells converted MY3, but only a marginal turnover of the dye
was found under these conditions with freely suspended cells of Sphingomonas sp. BN6. Under anaerobic conditions, suspended cells of Sphingomonas sp. BN6 reductively cleaved the azo bond of MY3 to 6-aminonaphthalene-2-sulfonate (6A2NS) and 5-aminosalicylate. The turnover
of MY3 by the immobilized cells under aerobic conditions resulted in the formation of more than equimolar amounts of 5-aminosalicylate,
but almost no (6A2NS) was detected. Cells of Sphingomonas sp. BN6 aerobically oxidize 6A2NS to 5-aminosalicylate. It was therefore concluded that the cells in the anaerobic center
of the alginate beads reduced MY3 to 6A2NS and 5-aminosalicylate and that 6A2NS was oxidized to 5-aminosalicylate by those
cells that were immobilized in the outer aerobic zones of the alginate beads. The presence of oxygen gradients within the
alginate beads was verified by using oxygen micro-electrodes. A coimmobilisate of Sphingomonas sp. BN6 with a 5-aminosalicylate degrading bacterium completely degraded MY3. The immobilized cells also converted the sulfonated
azo dyes Amaranth and Acid Red␣1.
Received: 6 May 1996 / Received revision: 6 August 1996 / Accepted: 12 August 1996 相似文献
11.
T. Matsunaga H. Sudo H. Takemasa Y. Wachi N. Nakamura 《Applied microbiology and biotechnology》1996,45(1-2):24-27
The cyanobacterium, Aphanocapsa halo-phytia MN-11, was immobilized in calcium alginate gel and coated on light-diffusing optical fibers (LDOF) for sulfated extracellular
polysaccharide production. Results indicated that sulfated extracellular polysaccharide production depends on the number of
immobilized cells and the light intensity. In addition, the production rate reached 116.0 mg (mg dry cells)-1 day-1 when the cells that were immobilized on LDOF were incubated under a light intensity of 1380 cd sr m-2 at a cell concentration of 1.0×108 cells/cm3 gel. Cells immobilized on LDOF produced about ten times more sulfated extracellular polysaccharide than those immobilized
in calcium alginate beads only (11.7 mg(mg dry cells)-1 day-1).
Received: 31 March 1995/Revised last revision 12 June 1995/Accepted 26 July 1995 相似文献
12.
G. H. Schoutens M. C. H. Nieuwenhuizen N. W. F. Kossen 《Applied microbiology and biotechnology》1985,21(5):282-286
Summary The aim of this study was to find the conditions necessary for the continuous butanol production from whey permeate with Clostridium beyerinckii LMD 27.6, immobilized in calcium alginate beads. The influence of three parameters on the butanol production was investigated: the fermentation temperature, the dilution rate (during start-up and at steady state) and the concentration of calcium ions in the fermentation broth. It was found that both a fermentation temperature of 30° C and a dilution rate of 0.1 h-1 or less during the start-up phase are required to achieve continuous butanol production from whey permeate. Butanol can be produced continuously from whey permeate in reactor productivities sixteen times higher than those found in batch cultures with free C. beyerinckii cells on whey media. 相似文献
13.
Bovine serum albumin-loaded beads were prepared by ionotropic gelation of alginate with calcium chloride and chitosan. The
effect of sodium alginate concentration and chitosan concentration on the particle size and loading efficacy was studied.
The diameter of the beads formed is dependent on the size of the needle used. The optimum condition for preparation alginate–chitosan
beads was alginate concentration of 3% and chitosan concentration of 0.25% at pH 5. The resulting bead formulation had a loading
efficacy of 98.5% and average size of 1,501 μm, and scanning electron microscopy images showed spherical and smooth particles.
Chitosan concentration significantly influenced particle size and encapsulation efficiency of chitosan–alginate beads (p < 0.05). Decreasing the alginate concentration resulted in an increased release of albumin in acidic media. The rapid dissolution
of chitosan–alginate matrices in the higher pH resulted in burst release of protein drug. 相似文献
14.
Coprinus cinereus, which was able to decolorize the anthraquinone dye Cibacron Blue 3G-A (CB) enzymatically, was used as a biocatalyst for
the decolorization of synthetic solutions containing this reactive dye. Coprinus cinereus was immobilized in both calcium alginate and polyacrylamide gels, and was used for the decolorization of CB from synthetic
water by using a fluidized bed bioreactor. The highest specific decolorization rate was obtained when Coprinus cinereus was entrapped in calcium alginate beads, and was of about 3.84 mg g−1 h−1 with a 50% conversion time (t
1/2) of about 2.60 h. Moreover, immobilized fungal biomass in calcium alginate continuously decolorized CB even after 7 repeated
experiments without significant loss of activity, while polyacrylamide-immobilized fungal biomass retained only 67% of its
original activity. The effects of some physicochemical parameters such as temperature, pH and dye concentration on decolorization
performance of isolated fungal strain were also investigated. 相似文献
15.
The influence of a specific microelemental environment in alginate gel beads on the course of propionic acid fermentation 总被引:5,自引:0,他引:5
In this work the exchange of calcium, cobalt, iron, magnesium, zinc and manganese ions between alginate gel beads and casein
medium was investigated. The high release of calcium ions from alginate to the medium and the biosorption of some metal ions
were observed. The pure alginate gel adsorbed all the metal ions examined, from a fermentative medium. Gel with immobilized
cells of two strains of Propionibacterium freudenreichii subsp. shermanii showed an active ability to adsorb only cobalt, iron and zinc ions. In this way, a special microelemental
environment was created in the alginate gel. This resulted in an increase of propionic acid production and a decrease of vitamin
B12 biosynthesis.
Received: 30 April 1997 / Received revision: 2 July 1997 / Accepted: 4 July 1997 相似文献
16.
Summary A new mutant strain,Aspergillus niger GS-III, showing resistance to manganese ions inhibition of citric acid fermentation on a sugarcane molasses containing medium was induced fromAspergillus niger KCU 520, a high citric acid-yielding strain. In submerged, surface or continuous cultures in the presence of manganese ions concentration upto 1.5 ppm the mutant strain yielded citric acid about 90 KgM–3 . The citric acid yield was comparable to that obtained with the parental strain KCU 520 in the absence of manganese ions, but it was atleast 3-fold higher than that obtained by the latter in the presence of manganese ions. The mutant strain immobilized in calcium alginate beads was used in combination with surface-stabilized cultures for about 36-days in a continuous flow horizontal fermenter without any apparent loss in citric acid productivity. These results indicate that the manganese-resistant mutant is stable and may be used in the presence of sufficient manganese ions concentration (1.5 ppm) in the fermentation medium. This capability of the mutant strainA. niger GS-III has been correlated with greatly reduced levels (about one-thirds) of the NADP+ -isocitric dehydrogenase, one of the control points for citric acid accumulation. 相似文献
17.
Solid matrix characterization of immobilized Pseudomonas putida MTCC 1194 used for phenol degradation 总被引:2,自引:0,他引:2
Characterization studies of calcium alginate beads with encapsulated Pseudomonas putida MTCC 1194, used for the biodegradation of phenol, were carried out to investigate the reactivity, reusability and structural
strength of the solid matrix. Various techniques were employed to improve the structural stability of the immobilized solid
necessary for its use in commercial reactors like packed bed flow reactor, fluidized bed and CSTR systems. Experiments were
performed to establish the optimum conditions for durability, strength and steady biochemical reactivity. During a batch run
of 40 h a gradual decline in the rate of phenol degradation was observed with the immobilized system. The calcium alginate
beads with high structural strength yielded decreased activity. Treatment with a hardening agent like glutaraldehyde for different
concentrations and treatment times led to variations in structural stability, reusability and the extent of phenol degradation.
Scanning electron microscope studies of the immobilized solid indicated the internal distribution pattern of the cells encapsulated
in a calcium alginate bead.
Received: 13 November 1998 / Received revision: 27 January 1999 / Accepted: 31 January 1999 相似文献
18.
Copper and nickel adsorption onto calcium alginate, sodium alginate with an extracellular polysaccharide (EPS) produced by the activated sludge bacterium Chryseomonas luteola TEM05 and the immobilized C. luteola TEM05 from aqueous solutions were studied. After that, the multi metal ions containing these ions together were prepared and partial competitive adsorptions of these mixtures were also investigated. The metal adsorption of gel beads were carried out at pH 6.0, 25 °C. The maximum adsorption capacities in Langmuir isotherm for calcium alginate, calcium alginate + EPS, calcium alginate + C. luteola TEM05 and calcium alginate + EPS + C. luteola TEM05 were 1.505, 1.989, 1.976, 1.937 mmol/g dry weight for Cu(II) and 0.996, 1.224, 1.078, 1.219 mol/g dry weight for Ni(II), respectively.The competitive biosorption capacities of the carrier for all metal ions were lower than single conditions. 相似文献
19.
Christian Tamponnet Sylvie Boisseau Chantal Poujeol Maurice Lievremont Michel Simonneau 《Biotechnology Techniques》1991,5(4):289-294
Summary We report here improved immobilization conditions which permitted (i) to immobilize mouse neuroblastoma cells in calcium alginate
beads, (ii) to test the functions of using patch clamp techniques and (iii) to quantitatively analyze ligand interactions
with voltage-dependent sodium channels in neurons immobilized inside alginate beads. These results qualify this immobilization
technique as a biotechnological tool to isolate and/or purify ligands of neuronal membrane proteins.
A part of these results was presented at the International Symposium “Physiology of immobilized Cells” at Wageningnen, The
Netherlands, December 10–13, 1989 相似文献
20.
O2 consumption and CO2 production of free and immobilizedSaccharomyces uvarum in the presence of ethanol were compared. The protective effect of immobilization on the yeast ethanol tolerance at 5–20%
of ethanol was more evident in CO2 production than in O2 consumption. CO2 production by the yeast immobilized in calcium alginate and calcium pectate gel beads was approximately 2.5-times higher
than by the free yeast at 5 and 10% of ethanol. 4-Fold increase of CO2 production was observed at 15% ethanol. Immobilization in calcium-containing carriers (alginate, pectate) resulted in enhanced
activities of yeasts compared to the κ-carrageenan carrier. 相似文献