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1.
Mishra A 《Applied biochemistry and biotechnology》2006,135(1):33-42
This article reports the production of high levels of l-asparaginase from a new isolate of Aspergillus niger in solid state fermentation (SSF) using agrowastes from three leguminous crops (bran of Cajanus cajan, Phaseolus mungo, and Glycine max). When used as the sole source for growth in SSF, bran of G. max showed maximum enzyme production followed by that of P. mungo and C. cajan. A 96-h fermentation time under aerobic condition with moisture content of 70%, 30 min of cooking time and 1205–1405 μ range
of particle size in SSF appeared optimal for enzyme production. Enzyme yield was maximum (40.9±3.35 U/g of dry substrate)
at pH 6.5 and temperature 30±2°C. The optimum temperature and pH for enzyme activity were 40°C and 6.5, respectively. The
study suggests that choosing an appropriate substrate when coupled with process level optimization improves enzyme production
markedly. Developing an asparaginase production process based on bran of G. max as a substrate in SSF is economically attractive as it is a cheap and readily available raw material in agriculture-based
countries. 相似文献
2.
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
3.
G. Saucedo-Castañeda B. K. Lonsane J. M. Navarro S. Rogssos M. Raimbault 《Applied biochemistry and biotechnology》1992,36(1):47-61
Data on conversion of starch on biomass and ethanol bySchwanniomyces castellii in an aerobic-anaerobic solid state fermentation is reported.Schwanniomyces castellii grew exponentially in the aerobic phase (12 h) and simultaneously hydrolyzed nearly half (55%) of the starch initially present.
The accumulation of glucose increased up to 12 h, whereas maltose was nearly absent beyond 7 h. Shift of metabolism from oxidative
to fermentative pattern was observed about 10 h as a result of the build-up of CO2 level and faster utilization of O2. The ethanol production in the anaerobic phase reached the level of 89.3 mg ethanol/g initial dry matter by the end of 30
h. A total of 92.9% of the starch is utilized during the fermentation. The overall ethanol conversion yields are 57.8% of
the theoretical value, whereas in the anaerobic phase it was found to be 94.4%. The cell shape, its morphology, and the type
of attachment to the solid support were found to be similar in aerobic and anaerobic phases of fermentation. Data given in
this work indicate the feasibility of using one single fermenter for aerobic growth to generate inoculum as well as to simultaneously
hydrolyze the starch and subsequent anaerobic fermentation to produce ethanol. 相似文献
4.
The commercial production of mannitol involves high-pressure hydrogenation of fructose using a nickel catalyst, a costly process.
Mannitol can be produced through fermentation by microorganisms. Currently, a few Lactobacillus strains are used to develop an efficient process for mannitol bioproduction; most of the strains produce mannitol from fructose
with other products. An approach toward improving this process would be to genetically engineer Lactobacillus strains to increase fructose-to-mannitol conversion with decreased production of other products. We cloned the gene mtlK encoding mannitol-2-dehydrogenase (EC 1.1.1.67) that catalyzes the conversion of fructose into mannitol from Lactobacillus brevis using genomic polymerase chain reaction. The mtlK clone contains 1328 bp of DNA sequence including a 1002-bp open reading frame that consisted of 333 amino acids with a predicted
molecular mass of about 36 kDa. The functional mannitol-2-dehydrogenase was produced by overexpressing mtlK via pRSETa vector in Escherichia coli BL21pLysS on isopropyl-β-d-thiogalactopyranoside induction. The fusion protein is able to catalyze the reduction of fructose to mannitol at pH 5.35.
Similar rates of catalytic reduction were observed using either the NADH or NADPH as cofactor under in vitro assay conditions.
Genetically engineered Lactobacillus plantarum TF103 carrying the mtlK gene of L. brevis indicated increased mannitol production from glucose. The evaluation of mixed sugar fermentation and mannitol production
by this strain is in progress.
Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the names by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
5.
Betânia H. Lunelli Rafael R. Andrade Daniel I. P. Atala Maria Regina Wolf Maciel Francisco Maugeri Filho Rubens Maciel Filho 《Applied biochemistry and biotechnology》2010,161(1-8):227-237
Lactic acid is an important product arising from the anaerobic fermentation of sugars. It is used in the pharmaceutical, cosmetic, chemical, and food industries as well as for biodegradable polymer and green solvent production. In this work, several bacterial strains were isolated from industrial ethanol fermentation, and the most efficient strain for lactic acid production was selected. The fermentation was conducted in a batch system under anaerobic conditions for 50 h at a temperature of 34 °C, a pH value of 5.0, and an initial sucrose concentration of 12 g/L using diluted sugarcane molasses. Throughout the process, pulses of molasses were added in order to avoid the cell growth inhibition due to high sugar concentration as well as increased lactic acid concentrations. At the end of the fermentation, about 90% of sucrose was consumed to produce lactic acid and cells. A kinetic model has been developed to simulate the batch lactic acid fermentation results. The data obtained from the fermentation were used for determining the kinetic parameters of the model. The developed model for lactic acid production, growth cell, and sugar consumption simulates the experimental data well. 相似文献
6.
Effect of pretreatment on simultaneous saccharification and fermentation of hardwood into Acetone/Butanol 总被引:1,自引:0,他引:1
Shah M. M. Song S. K. Lee Y. Y. Torget Robert 《Applied biochemistry and biotechnology》1991,(1):99-109
Aspergillus niger NCIM 1207 produces high levels of extracellular beta-glucosidase and xylanase activities in submerged fermentation. Among the nitrogen sources, ammonium sulfate, ammonium dihydrogen orthophosphate, and corn-steep liquor were the best for the production of cellulolytic enzymes by A. niger. The optimum pH and temperature for cellulase production were 3.0-5.5 and 28 degrees C, respectively. The cellulase complex of this strain was found to undergo catabolite repression in the presence of high concentrations of glucose. Glycerol at all concentrations caused catabolite repression of cellulase production. The addition of glucose (up to 1% concentration) enhanced the production of cellulolytic enzymes, but a higher concentration of glucose effected the pronounced repression of enzymes. Generally the growth on glucose- or glycerol-containing medium was accompanied by a sudden drop in the pH of the fermentation medium to 2.0. 相似文献
7.
Clostridium acetobutylicum ATCC 824 was grown under three different acetone-butanol-ethanol (ABE) fermentation conditions: (1) strictly anaerobic conditions with vegetative inoculum; (2) semi-anaerobic conditions with vegetative inoculum; and (3) strictly anaerobic conditions with spore inoculum. Semi-anaerobic fermentation with vegetative inoculum and strictly anaerobic fermentation with spore inoculum produced solvents at high level. Strictly anaerobic fermentation with vegetative inoculum showed an “acid crash”, i.e. produced mainly acids and did not switch to predominant solvent production. The content of carbohydrates, nucleic acids, proteins and lipids in Clostridium cells during the fermentation were evaluated from the mid-IR spectra. The content of nucleic acids decreased with process time, and the lipid content increased, corresponding to ceasing growth and formation of the toxic fermentation products. It was shown that the physiological states of either solvent production or acid crash are reflected in the microbial biomass composition, which can be assessed by IR spectroscopy. 相似文献
8.
The major constraint in the enzymatic saccharification of biomass for ethanol production is the cost of cellulase enzymes.
Production cost of cellulases may be brought down by multifaceted approaches which includes the use of cheap lignocellulosic
substrates for fermentation production of the enzyme, and the use of cost efficient fermentation strategies like solid state
fermentation (SSF). The current study investigated the production of cellulase by Trichoderma reesei RUT C30 on wheat bran under SSF. Process parameters important in cellulase production were identified by a Plackett and Burman
design and the parameters with significant effects on enzyme production were optimized for maximal yield using a central composite
rotary design (CCD). Higher initial moisture content of the medium had a negative effect on production whereas incubation
temperature influenced cellulase production positively in the tested range. Optimization of the levels of incubation temperature
and initial moisture content of the medium resulted in a 6.2 fold increase in production from 0.605 to 3.8 U/gds of cellulase.
The optimal combination of moisture and temperature was found to be 37.56% and 30 °C, respectively, for maximal cellulase
production by the fungus on wheat bran. 相似文献
9.
Rodrigues Denise C. G. A. Suva Silvio S. Prata Arnaldo Marcio R. Felipe Maria das Gracas A. 《Applied biochemistry and biotechnology》1998,(1):869-875
Batch, fed-batch, and semicontinuous fermentation processes were used for the production of xylitol from sugarcane bagasse
hemicellulosic hydrolysate. The best results were achieved by the semicontinuous fermentation process: a xylitol yield of
0.79 g/g with an efficiency of 86% and a volumetric productivity of 0.66 g/L/h. 相似文献
10.
The acetone-butanol production by simultaneous saccharification and extractive fermentation (SSEF) was investigated. In the
SSEF employing cellulase enzymes andClostridium acetobutylicum, both glucan and xylan fractions of pretreated aspen are concurrently converted into acetone and butanol. Continuous removal
of the fermentation products from the bioreactor by extraction was an important factor that allowed long-term fed-batch operation.
The use of membrane extraction prevented the problems of phase separation and extractant loss. Increase in substrate feeding
as well as reduction of nutrient supply was found to be beneficial in suppressing the acid production, thereby improving the
solvent yield. Because of prolonged low growth conditions prevalent in the fed-batch operation, the butanol-to-acetone ratio
in the product was significantly higher at 2.6–2.8 compared to the typical value of two. 相似文献
11.
Assamoi AA Destain J Delvigne F Lognay G Thonart P 《Applied biochemistry and biotechnology》2008,145(1-3):87-98
Xylanase is produced by Penicillium canescens 10–10c from soya oil cake in static conditions using solid-state fermentation. The impact of several parameters such as the nature
and the size of inoculum, bed-loading, and aeration is evaluated during the fermentation process. Mycelial inoculum gives
more production than conidial inoculum. Increasing the quantity of inoculum enhances slightly xylanase production. Forced
aeration induces more sporulation of strain and reduces xylanase production. However, forced moistened air improves the production
compared to production obtained with forced dry air. In addition, increasing bed-loading reduces the specific xylanase production
likely due to the incapacity of the Penicillium strain to grow deeply in the fermented soya oil cake mass. Thus, the best cultivation conditions involve mycelial inoculum
form, a bed loading of 1-cm height and passive aeration. The maximum xylanase activity is obtained after 7 days of fermentation
and attains 10,200 U/g of soya oil cake. These levels are higher than those presented in the literature and, therefore, show
all the potentialities of this stock and this technique for the production of xylanase. 相似文献
12.
Bogar B Szakacs G Tengerdy RP Linden JC Pandey A 《Applied biochemistry and biotechnology》2002,102(1-6):453-461
Ten Aspergillus oryzae strains were screened in solid substrate fermentation for α-amylase production on spent brewing grain (SBG) and on corn fiber.
SBG proved to be a better substrate for enzyme production than corn fiber. A Plackett-Burman experimental design was used
to optimize the medium composition for the best strain. Solid substrate fermentation on optimized medium with A. oryzae NRRL 1808 (=ATCC 12892) strain in stationary 500-mL Erlenmeyer flask culture yielded 4519 U of α-amylase/g of dry matter
substrate in 3 d. The whole solid substrate fermentation material (crude enzyme, in situ enzyme) may be considered a cheap biocatalytic material for animal feed rations and for bioalcohol production from starchy
materials. 相似文献
13.
Silva Silvio S. Ribeiro JoÃo D. Felipe Maria G. A. Vitolo Michelle 《Applied biochemistry and biotechnology》1997,(1):557-564
Batch fermentations of sugar cane bagasse hemicellulosic hydrolysate treated for removing the inhibitors of the fermentation
were performed byCandida guilliermondii FTI20037 for xylitol production. The fermentative parameters agitation and aeration rate were studied aiming the maximization
of xylitol production from this agroindustrial residue. The maximal xylitol volumetric productivity (0.87 g/L h) and yield
(0.67 g/g) were attained at 400/min and 0.45 v.v.m. (KLa 27/h). According to the results, a suitable control of the oxygen input permitting the xylitol formation from sugar cane
bagasse hydrolysate is required for the development of an efficient fermentation process for large-scale applications. 相似文献
14.
Rosa S. M. A. Felipe M. G. A. Silva S. S. Vitolo M. 《Applied biochemistry and biotechnology》1998,(1):127-135
The effect of pH, time of fermentation, and xylose and glucose concentration on xylitol production, cell growth, xylose reductase
(XR), and xylitol dehydrogenase (XD) activities ofCandida guilliermondii FTI 20037 were determined. For attaining XR and XD activities of 129-2190 U/mg of protein and 24-917 U/mg of protein, respectively,
the cited parameters could vary as follows: initial pH: 3.0-5.0; xylose: 15-60 g/L; glucose: 0-5 g/L; and fermentation time:
12-24 h. Moreover, the high XR and XD activities occurred when the xylitol production by the yeast was less than 19.0 g/L. 相似文献
15.
Campos Edhilvia J. Qureshi Nasib Blaschek Hans P. 《Applied biochemistry and biotechnology》2002,98(1-9):553-561
In this article we report on acetone butanol ethanol (ABE) fermentation characteristics of degermed corn when using Clostridium beijerinckii BA101. Recent economic studies suggested that recovery of germ from corn and hence corn oil would help to make the ABE fermentation
process more economical. C. beijerinckii BA101 ferments corn mash efficiently to produce ABE under appropriate nutritional and environmental conditions. Corn mash
contains germ/corn oil that is, possibly, ancillary to the production of butanol during the ABE fermentation process. Since
the presence of corn oil is not a critical factor in solvent fermentation, it can be removed and this will allow for byproduct
credit. Batch fermentation of degermed corn resulted in 8.93 g/L of total ABE production as compared with 24.80 g/L of total
ABE when supplemented with P2 medium nutrients. During the course of the germ separation process, corn steeping is required
prior to grinding and removing the germ. It is likely that some nutrients from the corn are leached out during the steeping
process. This may reduce the rate of fermentation and impact the final concentration of butanol/ABE that can be achieved.
Fermentation of degermed corn with corn steep liquor resulted in the production of 19.28 g/L of ABE. 相似文献
16.
Pryor SW Gibson DM Hay AG Gossett JM Walker LP 《Applied biochemistry and biotechnology》2007,143(1):63-79
Bacillus subtilis strain TrigoCor 1448 was grown on wheat middlings in 0.5-l solid-state fermentation (SSF) bioreactors for the production
of an antifungal biological control agent. Total antifungal activity was quantified using a 96-well microplate bioassay against
the plant pathogen Fusarium oxysporum f. sp. melonis. The experimental design for process optimization consisted of a 26−1 fractional factorial design followed by a central composite face-centered design. Initial SSF parameters included in the
optimization were aeration, fermentation length, pH buffering, peptone addition, nitrate addition, and incubator temperature.
Central composite face-centered design parameters included incubator temperature, aeration rate, and initial moisture content
(MC). Optimized fermentation conditions were determined with response surface models fitted for both spore concentration and
activity of biological control product extracts. Models showed that activity measurements and spore production were most sensitive
to substrate MC with highest levels of each response variable occurring at maximum moisture levels. Whereas maximum antifungal
activity was seen in a limited area of the design space, spore production was fairly robust with near maximum levels occurring
over a wider range of fermentation conditions. Optimization resulted in a 55% increase in inhibition and a 40% increase in
spore production over nonoptimized conditions. 相似文献
17.
S. Roussos M. Raimbault J. -P. Prebois B. K. Lonsane 《Applied biochemistry and biotechnology》1993,42(1):37-52
A novel design of a large scale solid state fermenter, designated asZymotis—the condensed term based on Greek word “Zymothiras,” which means the fermenter, offers efficient control of various fermentation parameters such as temperature, moisture, and
aeration of the fermenting moist solids. A large quantity of metabolic heat can be easily removed by the novel cooling system
employed. The unit can be operated at different capacities simply by adding or removing the compartments. Its evaluation at
different capacities for cellulase production byTrichoderma harzianum gave similar performance as in the parallel fermentation under optimized parameters in laboratory scale column fermenter
of high efficiency. The design is entirely different from all the known fermenter designs and is of potential promise in facilitating
scale up of solid state fermentation for leading to industrial exploitation and harvesting numerous socioeconomic advantages
of the system. 相似文献
18.
Hayward Tammy Kay Hamilton Jenny Tholudur Arun McMillan James D. 《Applied biochemistry and biotechnology》2000,84(1-9):859-874
Researchers studying cellulase enzymes for the economical production of fuel ethanol envision cellulose as the carbon source.
However, submerged Trichoderma reesei cultures grown on cellulose exhibit high run-to-run variability. Thus, an investigation of 30 batch cellulase production
experiments was instrumental in determining fermentation conditions that improved enzyme titers, yields, and productivities.
Eighteen of the 30 batch experiments experienced minimal process upsets and were classified into eight groups based on agitation
rate, gas sparge rate, and the use of oxygen supplementation. Comparing corn steep liquor with yeast extract/peptone also
tested the effect of different sources of nitrogen in the media. Average 7-d enzyme titers were doubled from 4 to 8 FPU/mL
primarily by increasing aeration. 相似文献
19.
Damaso Mônica C. T. Andrade Carolina M. M. C. Pereira Nei 《Applied biochemistry and biotechnology》2000,84(1-9):821-834
The production of cellulase-free end oxylanase by the thermophilic fungus Thermomyces lanuginosus was investigated insemisolid fermentation and liquid fermentation. Different process variables were investigated in semisolid
fermentation, employing corncobas the carbon source. The best results were with the following conditions: grain size=4.5 mm,
solid:liquid ratio=1:2, and inoculum size=20% (v/v). Corncob, xylan, and xylose were the best inducers for endoxylanase production.
Additionally, organic nitrogen sources were necessary for the production of high endoxylanase activities. The crude enzyme
had optimum activity at pH 6.0 and 75°C, displaying a high thermostability. The apparent K
25 and V
max were 1.77 mg of xylan/mL and 21.5 U/mg of protein, respectively. 相似文献
20.
Sosulski Krystyna Wang Sunmin Ingledew W. M. Sosulski Frank W. Tang Juming 《Applied biochemistry and biotechnology》1997,(1):59-70
Rye, triticale, and barley were evaluated as starch feedstock to replace wheat for ethanol production. Preprocessing of grain
by abrasion on a Satake mill reduced fiber and increased starch concentrations in feedstock for fermentations. Higher concentrations
of starch in flours from preprocessed cereal grains would increase plant throughput by 8–23% since more starch is processed
in the same weight of feedstock. Increased concentrations of starch for fermentation resulted in higher concentrations of
ethanol in beer. Energy requirements to produce one L of ethanol from preprocessed grains were reduced, the natural gas by
3.5–11.4%, whereas power consumption was reduced by 5.2–15.6%. 相似文献