共查询到20条相似文献,搜索用时 46 毫秒
1.
The production of cellulase was investigated in semi-solid state culture using the immobilized mycelium of Trichoderma reesei mutants on polyurethane foam impregnated with lactose medium. An extremely high value of about 2.6 FPU/ml was reached after the cultivation of T. reesei D-78085 on a 0.5% lactose medium in continuous culture at a pH medium of 4.0 when a bioreactor with vertical polyurethane foam plates was used. The enzyme yield on lactose was 520 FPU/g of lactose metabolized in comparison with 160 FPU/g using a stirred tank bioreactor. 相似文献
2.
Alberto Domínguez Francisco J. Deive Lorenzo Pastrana Maria L. Rúa Maria A. Longo M. Angeles Sanroman 《Bioprocess and biosystems engineering》2010,33(3):347-354
Several studies in laboratory-scale bioreactors are undertaken in order to verify the beneficial effect of thermal spring
water in the culture medium of Thermus thermophilus HB27. Two bioreactor configurations, stirred tank and airlift, are investigated to determine the most suitable one to develop
a continuous process. Water mineral composition affects the lipolytic enzyme secretion and growth of T. thermophilus HB27 in both bioreactor configurations. Furthermore, the lipolytic activity is strongly enhanced when stirred tank bioreactor
is used. Moreover, operation in a stirred tank at an agitation rate of 650 rpm leads to the highest total lipolytic activity
(intra- and extracellular enzyme) around 280 U/L after 32 h. Continuous cultures operating in the optimised conditions determined
in batch cultures are carried out. It is noticeable that the stirred tank bioreactor was able to operate in a continuous flow
mode without operational problems. In addition, the lipolytic activity obtained is about 2-fold higher than that attained
in batch cultures. 相似文献
3.
Perfusion cultures of recombinant Chinese hamster ovary cells, producing recombinant antibody against the S surface antigen of Hepatitis B virus, were carried out in continuous and intermittent mode using a Centritech Lab II Centrifuge. In the continuous perfusion process, despite the absence of shear stress from the pump head, long-term operation was not possible because of continuously repeated exposure to oxygen limitation and low temperature, as well as shear stress from centrifugal force. In the intermittent perfusion processes, the frequency of cell-passage through the centrifuge was substantially reduced, compared with the continuous perfusion mode; however, the degree of reduction could not guarantee stable long-term operation. Although various operating parameters were applied in the intermittent perfusion cultures, high cell densities could not be maintained stably. In a single bioreactor culture system, a specific cell that is returned from the centrifuge to the bioreactor could be transferred from the bioreactor to the centrifuge again in the next cycle. These repetitive damages, caused by shear stress from the pump head and centrifugal force, as well as exposure to suboptimal conditions such as oxygen limitation and low temperature below 37 degrees C, were more serious at higher perfusion rates. Subsequently, damaged cells and dead cells were continuously accumulated in the bioreactor. Culture temperature shift from 37 to 33 degrees C increased antibody concentrations but showed inhibitory effects on cell growth. The negative effects of lowering culture temperature on cell growth overwhelmed the positive effects on antibody production. To protect cells from shear stress, Pluronic F-68 was 2-fold concentrated in the culture medium; nevertheless, a significantly higher concentration of Pluronic F-68 (2 g/L) may have inhibitory effects on cell growth. 相似文献
4.
S. Huerta E. Favela R. López-Ulibarri A. Fonseca G. Viniegra-González M. Gutiérrez-Rojas 《Biotechnology Techniques》1994,8(11):837-842
Summary A 130 litre packed-bed bioreactor was used for pectinase production with Aspergillus niger using absorbed substrate fermentation techniques. Pectinolytic enzyme activity and relative CO2 production were used as indicators of metabolic activity. Absorbed substrate fermentation is an efficient process for pectinase production and is also an interesting model because the culture medium, water, nutrients and specific inducers, can be designed at the desired concentrations. 相似文献
5.
Kamakshi Gupta P. K. Mishra Pradeep Srivastava 《Biotechnology and Bioprocess Engineering》2009,14(2):207-212
Lovastatin, a hypocholesterolemic agent, is a secondary metabolite produced by filamentous microorganism Aspergillus terreus in submerged batch cultivation. Lovastatin production by pellets and immobilized siran cells was investigated in an airlift
reactor. The process was carried out by submerged cultivation in continuous mode with the objective of increasing productivity
using pellet and siran supported growth of A terreus. The continuous mode of fermentation improves the rate of lovastatin production. The effect of dilution rate and aeration
rate were studied in continuous culture. The optimum dilution rate for pellet was 0.02 h−1 and for siran carrier was 0.025 h−1. Lovastatin productivity using immobilized siran carrier (0.0255 g/L/h) was found to be greater than pellets (0.022 g/L/h).
The productivity by both modes of fermentation was found higher than that of batch process which suggests that continuous
cultivation is a promising strategy for lovastatin production. 相似文献
6.
Response surface methodology (RSM) was applied to optimize the critical medium ingredients of Agaricus blazei. A three-level Box–Behnken factorial design was employed to determine the maximum biomass and extracellular polysaccharide
(EPS) yields at optimum levels for glucose, yeast extract (YE), and peptone. A mathematical model was then developed to show
the effect of each medium composition and its interactions on the production of mycelial biomass and EPS. The model predicted
the maximum biomass yield of 10.86 g/l that appeared at glucose, YE, peptone of 26.3, 6.84, and 6.62 g/l, respectively, while
a maximum EPS yield of 348.4 mg/l appeared at glucose, YE, peptone of 28.4, 4.96, 5.60 g/l, respectively. These predicted
values were also verified by validation experiments. The excellent correlation between predicted and measured values of each
model justifies the validity of both the response models. The results of bioreactor fermentation also show that the optimized
culture medium enhanced both biomass (13.91 ± 0.71 g/l) and EPS (363 ± 4.1 mg/l) production by Agaricus blazei in a large-scale fermentation process. 相似文献
7.
Grzegorz Janusz Jerzy Rogalski Janusz Szczodrak 《World journal of microbiology & biotechnology》2007,23(10):1459-1464
The wood-degrading basidiomycete Cerrena unicolor C-139 has been suggested as a potential producer of the industrially important enzyme laccase. Basic culture parameters influencing
the enzyme synthesis in shaken-flask and aerated bioreactor cultures were evaluated to improve the yields of the process.
Production of extracellular laccase was considerably enhanced by the addition of Cu2+ in the micromolar range to a carbon-sufficient and nitrogen-sufficient culture medium (C/N = 16.69). When an optimised medium
containing glucose (10 g/L) and l-asparagine (1.5 g/L) was used, and enzyme synthesis was stimulated by addition of 10 μM Cu2+ to the culture medium on days 3, 6 and 9, maximal laccase productivity obtained after 17 days’ cultivation in shaken flask
cultures was above 100,000 nkat/L. In fermenter fungal cultures, the influence of stabilisation of medium pH on laccase activity
was additionally studied. The use of a bioreactor with an automatic pH control set at pH 6.5 after 48-h incubation resulted
in the enzyme activity of 65,000 nkat/L after 8 days’ cultivation. 相似文献
8.
Müslüm Altun 《Preparative biochemistry & biotechnology》2019,49(5):493-500
AbstractThe production of polyhydroxyalkanoates (PHA) using digestate of chicken manure combined with waste sunflower oil as no-cost feedstocks in a multi-stage process was investigated. Using Cupriavidus necator H16 in combined culture media, a maximum PHA accumulation of 4.6?±?0.2?g/L at 75.1?±?1.4% of cell dry matter and a residual cell matter yield of 1.5?±?0.1?g/L were obtained after 96?hr of cultivation (30?°C, 160?rpm, pH 7.0) in flask-based experiments. Manure was acidogenically fermented in a continuous stirring tank reactor in fed-batch mode. The bioreactor was operated at varying organic loading rates (OLR) and hydraulic retention times (HRT) ranging from 1–4?g volatile solids (VS)/L/d and 4–8?days, respectively. Optimal operation was observed at an OLR of 4?g VS/L/d and an HRT of 4?days. Analysis showed the presence of significant amounts of ammonia, potassium, magnesium, calcium, and trace elements, i.e. Fe, Cu, Ni, Mn, Co, Zn, Cr in the digestate. The micro-filtered digestate was utilized as a complex culture media base while waste oil served as an additional carbon source and supplemented for effective PHA production. The total volatile fatty acid content of digestate greatly affected the growth performance of the PHA-producing microorganism Cupriavidus necator H16. 相似文献
9.
L. Sajc G. Vunjak-Novakovic D. Grubisic N. Kovačević D. Vuković B. Bugarski 《Applied microbiology and biotechnology》1995,43(3):416-423
The production of anthraquinones by Frangula alnus Mill. plant cells was used as a model system to evaluate the performance of a liquid-liquid extractive product-recovery process.
The shake flask experiments have shown higher production of anthraquinones in cell suspension and flask cultures of calcium-alginate-immobilized
cells when silicone oil was incorporated into the medium, compared to a control without silicone oil. An external-loop air-lift
bioreactor, developed and designed for the production and simultaneous extraction of extracellular plant cell products, was
regarded as a four-phase system, with dispersed gas, non-aqueous solvent and calcium-alginate-immobilized plant cells in Murashige
and Skoog medium. Continuous extraction of anthraquinones by silicone oil and n-hexadecane inside the bioreactor resulted in 10–30 times higher cell productivity, compared to that of immobilized cells
in a flask. Based on the mixing pattern, immobilized biocatalyst extraparticle and intraparticle diffusional constraints and
the kinetics of growth, substrate consumption and product formation, a mathematical model was developed to describe the time
course of a batch plant cell culture. The model showed satisfactory agreement with four sets of shake flask experiments and
three bioreactor production cycles.
Received: 18 March 1994/Received revision: 20 September 1994/Accepted: 28 September 1994 相似文献
10.
Toshiya Muranaka Hideo Ohkawa Yasuyuki Yamada 《Applied microbiology and biotechnology》1993,40(2-3):219-223
The scopolamine-releasing hairy root clone DL47-1 of Duboisia leichhardtii was cultured in an Amberlite XAD-2 column-combined bioreactor system for continuous production of scopolamine. The medium used was continuously exchanged during culture to maintain the electrical conductivity of the medium constant. After culturing the hairy roots in the system for 11 weeks, 0.5 g/l of scopolamine was obtained in the column. When the roots were cultures in the reactor system containing polyurethane foam or stainless-steel mesh to support the hairy roots, scopolamine recovery was increased. Thereafter, a two-stage culture, the first stage in the medium for hairy root growth and the second stage in the medium for scopolamine release, was carried out in this system by using a turbine-blade reactor with stainless-steel mesh as a support. Under these conditions, 1.3 g/l of scopolamine was recovered during 11 weeks of culture in the medium for scopolamine release. This bioreactor system seems applicable for the production of various plant metabolites by cultures of hairy roots.
Correspondence to: T. Muranaka 相似文献
11.
Isolation and characterization of microorganisms able to produce 1,3-propanediol under aerobic conditions 总被引:1,自引:0,他引:1
Jian Hao Rihui Lin Zongming Zheng Hongjuan Liu Dehua Liu 《World journal of microbiology & biotechnology》2008,24(9):1731-1740
Microbial fermentation under strictly anaerobic conditions has been conventionally used for the production of 1,3-propanediol,
a key raw material required for the synthesis of polytrimethylene terephthalate (PTT) and other polyester fibers. In the current
study, we have identified eight strains of microorganism which are able to produce 1,3-propanediol under aerobic condition.
Those strains were isolated from garden soil, which were enriched by culturing in LB medium with glycerol added under aerobic
condition. The identities of those strains were established based on their 16S rRNA sequences and physiological characteristics.
Results indicated 6 strains are Citrobacter freundii and 2 strains are Klebsiella pneumoniae subsp Penumoniae. One of Klebsiella pneumoniae subsp Penumoniae strains, designated as TUAC01, demonstrated comparable levels of 1,3-propanediol oxidoreductase, glycerol dehydratase and
glycerol dehydrogenase activity to the anaerobic microorganisms described in the literature. Accordingly, in larger scales
(5 l) fed-batch culture the TUAC01 strain showed a remarkable 1,3-propanediol producing potency under aerobic conditions.
60.1 g/l of 1,3-propanediol was yield after 42 h incubation in an agitating bioreactor; and in air-lift bioreactor 66.3 g/l
of 1,3-propanediol was yield after 58.5 h incubation. The aerobic ferment process, reduced the product cost and made the biological
method of 1,3-propanediol production more attractive. 相似文献
12.
Biodegradation of phenolic industrial wastewater in a fluidized bed bioreactor with immobilized cells of Pseudomonas putida 总被引:10,自引:0,他引:10
The paper presents the main results obtained from the study of the biodegradation of phenolic industrial wastewaters by a pure culture of immobilized cells of Pseudomonas putida ATCC 17484. The experiments were carried out in batch and continuous mode. The maximum degradation capacity and the influence of the adaptation of the microorganism to the substrate were studied in batch mode. Industrial wastewater with a phenol concentration of 1000 mg/l was degraded when the microorganism was adapted to the toxic chemical. The presence in the wastewater of compounds other than phenol was noted and it was found that Pseudomonas putida was able to degrade these compounds. In continuous mode, a fluidized-bed bioreactor was operated and the influence of the organic loading rate on the removal efficiency of phenol was studied. The bioreactor showed phenol degradation efficiencies higher than 90%, even for a phenol loading rate of 0.5 g phenol/ld (corresponding to 0.54 g TOC/ld). 相似文献
13.
The natural lignan podophyllotoxin, a dimerized product of two phenylpropanoid moieties which occurs in a few plant species, is a pharmacologically important compound for its anticancer activities. It is used as a precursor for the chemical synthesis of the anticancer drugs etoposide, teniposide and etopophose. The availability of this lignan is becoming increasingly limited because of the scarce occurrence of its natural sources and also because synthetic approaches for its production are still commercially unacceptable. Biotechnological production using cell culture may be considered as an alternative source. Selection of the best performing cell line, its maintenance and stabilization are necessary prerequisites for its production in bioreactors and subsequent scale-up of the cultivation process to the industrial level. Scale-up of growth and product yield depends on a multitude of factors, such as growth medium, physicochemical conditions, seed inoculum, type of reactor and processing conditions. The composition of the growth medium, elicitors and precursors, etc. can markedly influence the production. Optimum levels of parameters that facilitate high growth and product response in cell suspensions of Podophyllum hexandrum have already been determined by statistical design. P. hexandrum cells have successfully been cultivated in a 3-l stirred-tank bioreactor under low shear conditions in batch and fed-batch modes of operation. The batch kinetic data were used to identify the mathematical model which was then used to develop nutrient-feeding strategies for fed-batch cultivation to prolong the productive log phase of cultivation. An improvement in the production of podophyllotoxin to 48.8 mg l–1 in a cell culture of P. hexandrum was achieved, with a corresponding volumetric productivity of 0.80 mg l–1 day–1, when the reactor was operated in continuous cell-retention mode. Efforts are being made to further enhance its production levels by the development of hairy root culture or by varying the channeling of precursors towards the desired biosynthetic pathway by molecular approaches. 相似文献
14.
Kee-Yoeup Paek Eun-Joo Hahn Sung-Ho Son 《In vitro cellular & developmental biology. Plant》2001,37(2):149-157
Summary The application of bioreactor culture techniques for plant micropropagation is regarded as one of the ways to reduce production
cost by scaling-up and automation. Recent experiments are restricted to a small number of species that, however, demonstrate
the feasibility of this technology. Periodic immersion liquid culture using ebb and flood system and column-type bubble bioreactors
equipped with a raft support system to maintain plant tissues at the air and liquid interface were found to be suitable for
micropropagation of plants via the organogenic pathway. Balloon-type bubble bioreactors proved to be fit for micropropagation
via somatic embryogenesis with less shear stress on cultured cells. Several cultivars of Lilium were successfully propagated using a two-stage culture method in one bioreactor. A large number of small-scale segments were
cultured for 4 wk with periodic immersion liquid culture to induce multiple bulblets from each segment, then the bulblet induction
medium was changed into bulblet growth medium by employing a submerged liquid bioreactor system. This culture method resulted
in a nearly 10-fold increase in bulblet growth compared to conventional culture with solid medium. About 20 000 cuttings of
virus-free potato could be obtained from 120 singlenode explants in a 20-liter balloon-type bubble bioreactor after 8 wk of
culture. The percentage of ex vitro survival and root induction of the cuttings was more than 95%. Other successful results were obtained from the micropropagation
and transplant production of chrysanthemum, sweetpotato, Chinese foxglove. Propagation systems via somatic embryogenesis in
Acanthopanax koreanum and thornless Aralia elata were established using a liquid suspension of embryogenic determined cells. More than 500 000 somatic embryos in different
stages were harvested from a 10-liter balloon-type bubble bioreactor after a 6-wk culture. Further development of these embryos
in solid medium and eventually in the field was successful. The bioreactor system could reduce initial and operational cost
for micropropagation, but further development of sophisticated technology might be needed to apply this system to plant micropropagation
industries. 相似文献
15.
Natural cashew apple juice as fermentation medium
for biosurfactant production by Acinetobacter calcoaceticus 总被引:1,自引:0,他引:1
Maria V. P. Rocha Adriano H. S. Oliveira Maria C. M. Souza Luciana R. B. Gonçalves 《World journal of microbiology & biotechnology》2006,22(12):1295-1299
The success of biosurfactant production depends on the development of cheaper processes based on the use of low cost raw materials, which account for 10–30% of the overall process cost. In Brazil, the cashew apple agroindustry plays an outstanding role in the local economy. However, only a small part of the pseudofruit produced is used industrially and the amount wasted (about 94%) presents high potential as fermentation media, since it is rich in carbohydrate, fibers, vitamins and minerals salts. In this work, the performance of cashew apple juice (CAJ) as a complex medium for Acinetobacter calcoaceticus growth and production of biosurfactant was investigated. The microorganism was able to grow and to produce biosurfactant on a defined culture medium and on CAJ, reducing the surface tension of both media. The biosurfactant also achieved a maximum emulsion index of 80% for kerosene, when defined medium was used. 相似文献
16.
Human serum albumin (HSA) is the most widely used clinical serum protein. Currently, commercial HSA can only be obtained from
human plasma, due to lack of commercially feasible recombinant protein expression systems. In this study, inducible expression
and secretion of HSA by transformed rice suspension cell culture was established. Mature form of HSA was expressed under the
control of the sucrose starvation-inducible rice α Amy3 promoter, and secretion of HSA into the culture medium was achieved by using the α Amy3 signal sequence. High concentrations of HSA were secreted into culture medium in a short time (2–4 days) by sucrose depletion
after cell concentrations had reached a peak density in culture medium containing sucrose. The recombinant HSA had the same
electrophoretic mobility as commercial HSA and was stable and free from apparent proteolysis in the culture medium. In a flask
scale culture with repeated sucrose provision-depletion cycles, HSA was stably produced with yields up to 11.5% of total medium
proteins or 15 mg/L per cycle after each sucrose provision-depletion cycle. A bubble column type bioreactor was designed for
production of HSA. In the bioreactor scale culture, HSA was produced with yields up to 76.4 mg/L 4 days after sucrose depletion.
HSA was purified from the culture medium to high purity by a simple purification scheme. Enrichment of HSA in culture medium
simplifies downstream purification, minimizes protease degradation, and may reduce production cost. The combination of a DNA
construct containing the α Amy3 promoter and signal sequence, and the use of a rice suspension cell culture can provide an effective system for the production
of recombinant pharmaceutical proteins. 相似文献
17.
The performance of a bioreactor in meeting process goals is affected by the microorganism used, medium composition, and operating conditions. A typical bioreactor uses a supervisory control and data acquisition (SCADA) system for control, and a combination of software and hardware tools for real‐time data analysis. However, when the process is disrupted by utility or instrumentation failure, typical process controllers may be unable to reinstate normal operating conditions before the cells in the reactor shift to unfavorable metabolic regimes. The objective of this study is to examine how the response of a controller affects process recovery when disruptive incidences occur under a process analytical technology (PAT) framework. The process used for this investigation is the production of lethal toxin‐neutralizing factor (LTNF) by Escherichia coli (E. coli), which is controlled by a decoupled input–output‐linearizing controller (DIOLC). The performance of the DIOLC is compared to a proportional integral derivative (PID) controller subjected to the same conditions. The disruptions are introduced manually and the effect of controller action on process recovery and LTNF synthesis is measured in terms of peak purity and concentration. It is observed that DIOLC performs better after reinstating operating conditions and results in a meaningful improvement in performance. 相似文献
18.
Wei Zhang Hong Liu Xia Li Duo Liu Xiu‐Tao Dong Fei‐Fei Li En‐Xu Wang Bing‐Zhi Li Ying‐Jin Yuan 《Engineering in Life Science》2017,17(9):1021-1029
Heterologous production of naringenin, a valuable flavonoid with various biotechnological applications, was well studied in the model organisms such as Escherichia coli or Saccharomyces cerevisiae. In this study, a synergistic co‐culture system was developed for the production of naringenin from xylose by engineering microorganism. A long metabolic pathway was reconstructed in the co‐culture system by metabolic engineering. In addition, the critical gene of 4‐coumaroyl‐CoA ligase (4CL) was simultaneously integrated into the yeast genome as well as a multi‐copy free plasmid for increasing enzyme activity. On this basis, some factors related with fermentation process were considered in this study, including fermented medium, inoculation size and the inoculation ratio of two microbes. A yield of 21.16 ± 0.41 mg/L naringenin was produced in this optimized co‐culture system, which was nearly eight fold to that of the mono‐culture of yeast. This is the first time for the biosynthesis of naringenin in the co‐culture system of S. cerevisiae and E. coli from xylose, which lays a foundation for future study on production of flavonoid. 相似文献
19.
Manoj Jangra Prasanna D. Belur Larysa B. Oriabinska Olexii M. Dugan 《Engineering in Life Science》2016,16(3):247-253
Most commercial probiotic products intended for pharmaceutical applications consist of combinations of probiotic strains and are available in various forms. The development of co‐culture fermentation conditions to produce probiotics with the correct proportion of viable microorganisms would reduce multiple operations and the associated costs. The aim of this study was to develop a fermentation medium and process to achieve biomass comprising the desired proportion of two probiotic strains in co‐culture. Initially, a quantification medium was developed, and the method was optimized to allow the quantification of each strain's biomass in a mixture. The specific growth rates of Lactobacillus delbrueckii spp. bulgaricus and Lactobacillus plantarum were determined in media with different carbon sources. The inoculum volume was optimized to achieve equal proportion of biomass in co‐culture fermentation in test tubes. Next, fermentation was carried out in a 3‐L bioreactor. A biomass concentration of 2.06 g/L, with L. delbrueckii spp. bulgaricus and L. plantarum in the ratio of 47%:53% (by weight), was achieved with concomitant production of 12.69 g/L of lactic acid in 14 h. The results show that with careful manipulation of process conditions, it is possible to achieve the desired proportion of individual strains in the final biomass produced by co‐culture fermentation. This process may serve as a model to produce multistrain probiotic drugs at industrial scale. 相似文献
20.
The objective of this study is to improve cephalosporin C (CPC) production by optimization of medium and culture conditions.
A statistical method was introduced to optimize the main culture medium. The main medium for CPC production was optimized
using a statistical method. Glucose and corn steep liquor (CSL) were found to be the most effective factors for CPC production.
Glucose and CSL were optimized to 2.84 and 6.68%, respectively. CPC production was improved 50% by feeding of 5% rice oil
at day 3rd and 5th day during the shake flask culture ofC. acremonium M25. The effect of agitation speeds on CPC production in a 2.5-L bioreactor was also investigated with fed-batch mode. The
maximum cell mass (54.5 g/L) was obtained at 600 rpm. However, the maximum CPC production (0.98 g/L) was obtained at 500 rpm.
At this condition, the maximum CPC production was improved about 132% compared to the result with batch flask culture. 相似文献