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1.
Among the lignocellulosic substrates tested, wheat bran supported a high xylanase (EC 3.2.1.8) secretion by Humicola lanuginosa in solid-state fermentation (SSF). Enzyme production reached a peak in 72 h followed by a decline thereafter. Enzyme production
was very high (7832 U/g of dry moldy bran) when wheat bran was moistened with tap water at a substrate-to-moistening agent
ratio of 1:2.5 (w/v) and an inoculum level of 3 × 106 spores/10 g of wheat bran at a water activity (a
w
) of 0.95. Cultivation of the mold in large enamel trays yielded a xylanase titer comparable with that in flasks. Parametric
optimization resulted in a 31% increase in enzyme production in SSF. Xylanase production was approx 23-fold higher in SSF
than in submerged fermentation (SmF). A threshold constitutive level of xylanase was secreted by H. lanuginosa in a medium containing glucose as the sole carbon source. The enzyme was induced by xylose and xylan. Enzyme synthesis was
repressed beyond 1.0% (w/v) xylose in SmF, whereas it was unaffected up to 3.0% (w/w) in SSF, suggesting a minimization of
catabolite repression in SSF. 相似文献
2.
Dutra JC da C Terzi S Bevilaqua JV Damaso MC Couri S Langone MA Senna LF 《Applied biochemistry and biotechnology》2008,147(1-3):63-75
The aim of this study was to monitor the biomass growth of Aspergillus niger in solid-state fermentation (SSF) for lipase production using digital image processing technique. The strain A. niger 11T53A14 was cultivated in SSF using wheat bran as support, which was enriched with 0.91% (m/v) of ammonium sulfate. The addition of several vegetable oils (castor, soybean, olive, corn, and palm oils) was investigated
to enhance lipase production. The maximum lipase activity was obtained using 2% (m/m) castor oil. In these conditions, the growth was evaluated each 24 h for 5 days by the glycosamine content analysis and digital
image processing. Lipase activity was also determined. The results indicated that the digital image process technique can
be used to monitor biomass growth in a SSF process and to correlate biomass growth and enzyme activity. In addition, the immobilized
esterification lipase activity was determined for the butyl oleate synthesis, with and without 50% v/v hexane, resulting in 650 and 120 U/g, respectively. The enzyme was also used for transesterification of soybean oil and ethanol
with maximum yield of 2.4%, after 30 min of reaction. 相似文献
3.
Laccase production by solid-state fermentation (SSF) using an indigenously isolated white rot basidiomycete Ganoderma sp. was studied. Among the various agricultural wastes tested, wheat bran was found to be the best substrate for laccase
production. Solid-state fermentation parameters such as optimum substrate, initial moisture content, and inoculum size were
optimized using the one-factor-at-a-time method. A maximum laccase yield of 2,400 U/g dry substrate (U/gds) was obtained using
wheat bran as substrate with 70% initial moisture content at 25°C and the seven agar plugs as the inoculum. Further enhancement
in laccase production was achieved by supplementing the solid-state medium with additional carbon and nitrogen source such
as starch and yeast extract. This medium was optimized by response surface methodology, and a fourfold increase in laccase
activity (10,050 U/g dry substrate) was achieved. Thus, the indigenous isolate seems to be a potential laccase producer using
SSF. The process also promises economic utilization and value addition of agro-residues. 相似文献
4.
Aspergillus oryzae SBS50 secreted a high titre of phytase in solid-state fermentation (SSF) using wheat bran at 30 °C after 96 h at the initial substrate to moisture ratio of 1:2 and a water activity of 0.95. The production of phytase increased when wheat bran was supplemented with sucrose and beef extract. Further enhancement in enzyme production was recorded when the substrate was supplemented with the surfactant Triton X-100 (145 U/g of DMB). An overall 29-fold improvement in phytase production was achieved owing to optimization. Under optimized conditions, the mould secreted 9.3-fold higher phytase in SSF as compared to submerged fermentation (SmF). The mesophilic mould also secreted amylase, cellulase (CMCase), pectinase and xylanase along with phytase in SSF. Scanning electron microscopy revealed luxuriant growth of A. oryzae on wheat bran with abundant spores. The enzyme dephytinized wheat bran with concomitant liberation of inorganic phosphate. 相似文献
5.
Marcio Antonio Mazutti Aline Skrowonski Gabriela Boni Giovani Leone Zabot Marceli Fernandes Silva Débora de Oliveira Marco Di Luccio Francisco Maugeri Filho Maria Isabel Rodrigues Helen Treichel 《Applied biochemistry and biotechnology》2010,160(3):682-693
Inulinase belongs to an important class of enzymes as it can be used to produce high-fructose syrups by enzymatic hydrolysis of inulin and fructooligosaccharides, which has been used as functional food. This work aimed to carry out a partial characterization of the crude enzymatic extract of two different inulinases, obtained by solid-state fermentation (SSF) and submerged fermentation (SmF), using agroindustrial residues as substrates. The crude enzymatic extract obtained by SmF showed an optimal pH and temperature for hydrolytic activity of 4.5 and 55?°C, respectively; and that obtained by SSF conducted to optimal pH and temperature of 5.0 and 55?°C, respectively. Both enzymes presented high thermostability, with a D value of 230.4 h and 123.1 h for SmF and SSF, respectively. The inulinase produced by SmF showed highest stability at pH?4.4, while inulinase obtained by SSF was more stable at pH?4.8. The results showed that inulinase obtained by SmF is less susceptible to pH effect and the inulinase obtained by SSF is more resistant to higher temperatures. 相似文献
6.
Qing-Shan Li Juan-Juan Xu Jian-Jiang Zhong 《Applied biochemistry and biotechnology》1997,62(2-3):243-250
Effects of water content and carbon and nitrogen sources on the production ofL-glutamate oxidase (GOD) by solid state fermentation (SSF) ofStreptomyces sp. N1 were investigated in a 250-mL shake flask. The results show that in the solid medium containing wheat bran 98% (w/w), KCl
0.2% (w/w), and MgCl2 0.2% (w/w), addition of 2.0-mL water per gram solid medium and 0.4% (w/w) (NH4)2SO4 was the best for GOD production. In this work, we also developed a simple technique forin situ measuring oxygen uptake rate (OUR) and carbon dioxide evolution rate (CER) in SSF in a shake flask based on the principle
of Warburg manometer. The method was successfully applied to determine OUR and CER values in SSF ofStreptomyces sp. N1. The results indicate that the largest OUR value was detected about one or two days ahead of the highest GOD activity reached
depending on the fermentation conditions, and the OUR may be used as anin situ indicator of GOD production in the SSF process. 相似文献
7.
Renovato J Gutiérrez-Sánchez G Rodríguez-Durán LV Bergman C Rodríguez R Aguilar CN 《Applied biochemistry and biotechnology》2011,165(1):382-395
Significant differences on structure, stability, and catalytic properties of tannase were found when this enzyme was produced
under solid-state and submerged fermentations (SSF and SmF) by Aspergillus niger. The specific activity was 5.5 times higher on SSF than in SmF. Significant differences in isoelectric points of tannases
were found. The pH optima for both types of enzyme was found at 6 and the pH stability of SSF and SmF tannase were at 6 and
5–8, respectively. The optimal temperature range was from 50 to 60 °C for SmF tannase and 60 °C for SSF tannase, and both
enzyme types showed tolerance to high temperatures (60–70 °C). The SSF tannase showed a major specificity for methyl gallate
substrate while SmF tannase for tannic acid. All metal ions tested, had an activity inhibition from 30–46% on SSF tannase.
SDS-PAGE analysis as well as gel localization studies of both SSF and SmF purified tannases showed a single band with a molecular
weight of 102 and 105 kDa, respectively. Different levels of glycosylation were found among SSF and SmF purified tannases.
This is the first report about structural differences among tannase produced under SSF and SmF and this study provides basis
for explanation of the stability and catalytic differences observed previously for this two tannase types. 相似文献
8.
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
9.
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
10.
Due to great interest on producing bioactive compounds for functional foods and biopharmaceuticals, it is important to explore the microbial degradation of potential sources of target biomolecules. Gallotannins are polyphenols present in nature, an example of them is tannic acid which is susceptible to enzymatic hydrolysis. This hydrolysis is performed by tannase or tannin acyl hydrolase, releasing in this way, biomolecules with high-added value. In the present study, chemical profiles obtained after fungal degradation of tannic acid under two bioprocesses (submerged fermentation (SmF) and solid state fermentation (SSF)) were determined. In both fermentation systems (SmF and SSF), Aspergillus niger GH1 strain and tannic acid as a sole carbon source and inducer were used (the presence of tannic acid promotes production of enzyme tannase). In case of SSF, polyurethane foam (PUF) was used like as support of fermentation; culture medium only was used in case of submerged fermentation. Fermentation processes were monitored during 72 h; samples were taken kinetically every 8 h; and all extracts obtained were partially purified to obtain polyphenolic fraction and then were analyzed by liquid chromatography-mass spectrometry (LC-MS). Molecules like gallic acid and n-galloyl glucose were identified as intermediates in degradation of tannic acid; during SSF was identified ellagic acid production. The results obtained in this study will contribute to biotechnological production of ellagic acid. 相似文献
11.
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
12.
Ethanol production was studied in simultaneous saccharification and fermentation (SSF) of steam-pretreated spruce at 42°C,
using a thermotolerant yeast. Three yeast strains of Kluyveromyces marxianus were compared in test fermentations. SSF experiments were performed with the best of these on 5% (w/w) of substrate at a
cellulase loading of 37 filter paper units/g of cellulose, and a β-glucosidase loading of 38 IU/gof cellulose. The detoxification
of the substrate and the lack of pH control in the experiments increased the final ethanol concentration. The final ethanol
yield was 15% lower compared to SSF with Saccharomyces cerevisiae at 37°C, owing to the cessation of ethanol fermentation after the first 10 h. 相似文献
13.
To increase the value of coproducts from corn ethanol fermentation and soybean aqueous processing, distiller??s dried grains with solubles (DDGS) and soybean cotyledon fiber were used as the substrates for solid state fermentation (SSF) to improve feed digestibility. Aspergillus oryzae, Trichoderma reesei, and Phanerochaete chrysosporium were chosen as they produce desirable enzymes and are widely used in SSF for feed. The results showed that the cellulase and xylanase activities were significantly increased after 7?days of fermentation, and cellulose and hemicellulose degradation was also greatly increased. When soybean fiber was used as SSF substrate, the maximum activities of the cellulase and xylanase were 10.3 and 84.2?IU/g substrate (dry weight basis) after SSF treatment, respectively. However, the enzyme activities were relatively low in DDGS, and the growth of the three fungi was poor. The fungi grew better when soybean cotyledon fiber was added to DDGS, and cellulase and xylanase activity increased with the increase of soybean fiber content. Porosity was identified as an important factor for SSF because the addition of inert soybean hull alone improved the fungi growth significantly. These data suggest that the nutritional value of DDGS and soybean cotyledon fiber as monogastric animal feed could be greatly enhanced by SSF treatment. 相似文献
14.
Ethanol production from Jerusalem artichoke was studied using inulinase and Z.mobilis by simultaneous saccharification and fermentation (SSF) process. The SSF process showed higher ethanol yield and productivity
than the acid or enzymatic prehydrolyzed two-step process. The optimum temperature and inulinase concentration for SSF were
35°C and 0.25% (v/w, 4.4 units/g of sugar), respectively. In order to operate the SSF process in a continuous mode, inulinase
and Z.mobilis cells were coimmobilized in alginate beads, using chitin as a matrix for enzyme immobilization. The maximum ethanol productivity
of the continuous SSF process was 55.1 g/L/h, with 55% conversion yield. At the conversion yield of 90%, the productivity
was 32.7 g/L/h. The continuous SSF system could be operated stably over 2 wk with an ethanol concentration of 48.6 g/L (95%
of theoretical yield). 相似文献
15.
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
16.
Development of a bionematicide with Paecilomyces lilacinus to control Meloidogyne incognita 总被引:1,自引:0,他引:1
Brand D Roussos S Pandey A Zilioli PC Pohl J Soccol CR 《Applied biochemistry and biotechnology》2004,118(1-3):81-88
Root-knot disease caused by Meloidogyne incognita is a matter of grave concern because it affects several economically important crop plants. The use of solid-state fermentation
(SSF) may help to elaborate efficient formulations with fungi to be employed in the biologic control of nematodes. Attempts
were made to select low-cost substrates for spore production of a strain of Paecilomyces lilacinus with known nematicide capacity. Coffee husks, cassava bagasse, and defatted soybean cake were utilized as substrates, and
sugarcane bagasse was used as support. Fermentations were carried out in flasks covered with filter paper at 28°C for 10 d.
The products obtained by SSF were evaluated for their nematicide activity in pot experiments containing one seedling of the
plant Coleus inoculated with the nematode M. incognita. The plants were evaluated 2 mo after inoculation. Fermented products showed a reduction in the number of nematodes. The
best results were obtained with defatted soybean cake, which showed almost 100% reduction in the number of nematodes; the
reduction with coffee husk was 80% and with cassava bagasse was about 60%. 相似文献
17.
Stajic M Persky L Cohen E Hadar Y Brceski I Wasser SP Nevo E 《Applied biochemistry and biotechnology》2004,117(3):155-164
Species of the genus Pleurotus are among the most efficient natural species in lignin degradation belonging to the subclass of ligninolytic organisms that
produce laccase (Lac), Mn-dependent peroxidase (MnP), versatile peroxidase (VP), and the H2O2-generating enzyme aryl-alcohol oxidase, but not lignin peroxidases. Production of Lac and oxidation of 2,6-dimethoxyphenol
(DMP) in the presence and absence of Mn2+ were detected both in submerged fermentation (SF) of dry ground mandarine peels and in solid-state fermentation (SSF) of
grapevine sawdust in all investigated Pleurotus species and strains. Evidence of cultivation methods having a distinct influence on the level of enzyme activities has been
demonstrated. Most of the species and strains had higher Lac activity under SSF conditions than under SF conditions. DMP oxidation
in the presence and absence of Mn2+ was detected in all investigated species and strains, but was lower under SF conditions than under SSF conditions for most
of them. However, relative activities of DMP oxidation in the absence of Mn2+, as percentages of activity agasint DMP in the presence of Mn2+, were higher under conditions of SF than in SSF cultures in most of the investigated species and strains. The obtained results
showed that strains of different origins have different efficiently ligninolytic systems and that conditions of SSF are more
favorable for ligninolytic activity than those in SF owing to their similarity to natural conditions on wood substrates. 相似文献
18.
Valeria F. Soares Leda R. Castilho Elba P. S. Bon Denise M. G. Freire 《Applied biochemistry and biotechnology》2005,121(1-3):311-319
A Bacillus subtilis isolate was shown to be able to produce extracellular protease in solid-state fermentations (SSF) using soy cake as culture
medium. A significant effect of inoculum concentration and physiological age on protease production was observed. Maximum
activities were obtained for inocula consisting of exponentially growing cells at inoculum concentrations in the range of
0.7–2.0 mg g−1. A comparative study on the influence of cultivation temperature and initial medium pH on protease production in SSF and
in submerged fermentation (SF) revealed that in SSF a broader pH range (5–10), but the same optimum temperature (37°C), is
obtained when compared to SF. A kinetic study showed that enzyme production is associated with bacterial growth and that enzyme
inactivation begins before biomass reaches a maximum level for both SF and SSF. Maximum protease activity and productivity
were 960 U g−1 and 15.4 U g−1 h−1 for SSF, and 12 U mL−1 and 1.3 U mL−1 h−1 for SF. When SSF protease activity was expressed by volume of enzyme extract, the enzyme level was 10-fold higher and the
enzyme productivity 45% higher than in SF. These results indicate that this bacterial strain shows a high biotechnological
potential for protease production in solid-state fermentation. 相似文献
19.
Wong YP Saw HY Janaun J Krishnaiah K Prabhakar A 《Applied biochemistry and biotechnology》2011,164(2):170-182
Solid-state fermentation (SSF) was employed to enhance the nutritive values of palm kernel cake (PKC) for poultry feeding.
Aspergillus flavus was isolated from local PKC and utilized to increase the mannose content of PKC via the degradation of β-mannan in PKC; evaluation
was done for batch SSF in Erlenmeyer flasks and in a novel laterally aerated moving bed (LAMB) bioreactor. The optimum condition
for batch SSF in flasks was 110% initial moisture content, initial pH 6.0, 30 °C, 855 μm particle size, and 120 h of fermentation,
yielding 90.91 mg mannose g−1 dry PKC (5.9-fold increase). Batch SSF in the LAMB at the optimum condition yielded 79.61 mg mannose g−1 dry PKC (5.5-fold increase) within just 96 h due to better heat and mass transfer when humidified air flowed radially across
the PKC bed. In spite of a compromise of 12% reduction in mannose content when compared with the flasks, the LAMB facilitated
good heat and mass transfer, and improved the mannose content of PKC in a shorter fermentation period. These attributes are
useful for batch production of fermented PKC feed in an industrial scale. 相似文献
20.
Thermostable phytase production by Thermoascus aurantiacus in submerged fermentation 总被引:2,自引:0,他引:2
Nampoothiri KM Tomes GJ Roopesh K Szakacs G Nagy V Soccol CR Pandey A 《Applied biochemistry and biotechnology》2004,118(1-3):205-214
Phytases act on phytic acid, an antinutrient factor present in animal feeds, and release inorganic phosphate. We optimized
the production parameters for phytase production using Thermoascus aurantiacus (TUB F 43), a thermophilic fungal culture, by submerged fermentation. A semisynthetic medium containing glucose, starch,
peptone, and minerals supplemented with 3.75% (w/v) wheat bran particles was found to be the best production medium among
the various combinations tried. Further supplementation of this medium with surfactants such as Tween-20 and Tween-80 considerably
enhanced the enzyme yield. A maximum phytase activity (468.22 U/mL) was obtained using this production medium containing 2%
(v/v) Tween-20 after 72 h of fermentation at 45°C in shake-flask cultures with a rotation of 150 rpm. Herein we present details
of a few of the process parameter optimizations. The phytase enzyme was found to be thermostable, and the optimal temperature
for phytase activity was found to be 55°C. However, 80% of the activity still remained when the temperature was shifted to
70°C. 相似文献