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1.
Phytase production by fermentation of recombinant Pichia pastoris in monosodium glutamate wastewater
Yingguo Bai Peilong Yang Yaru Wang Pengjun Shi Huiying Luo Kun Meng Bo Wu Bin Yao 《World journal of microbiology & biotechnology》2009,25(9):1643-1649
A novel method is proposed to produce both phytase and single-cell protein in recombinant Pichia pastoris fermentation using monosodium glutamate wastewater (MSGW) as the basal medium. Recombinant P. pastoris MR33 transformed with a phytase gene (AppA-m) from Escherichia coli was constructed and showed capability to utilize ammonium as the only nitrogen source. The fermentation medium was optimized
in shake flasks by single-factor test and response surface methodology. A fed-batch system containing 30% MSGW, 50 g/l glucose,
1.58 g/l CaSO4, 5.18 g/l MgSO4 and 6.67 g/l KH2PO4 was developed in a 3.7-l bioreactor. The maximum phytase activity in the MSGW medium reached 3,380 U/ml, 84.2% of that in
chemically defined medium, and the dry cell weight was 136 g/l. The single-cell protein (SCP; 46.66% dry cell weight) contains
a variety of amino acids and is low in fat, which is ideal for utilization in animal feed. Thus, it is feasible to use MSGW
medium for the production of enzymes that can be expressed in P. pastoris. 相似文献
2.
Seda Karasu Yalçin Zekiye Yeşim Özbaş 《World journal of microbiology & biotechnology》2005,21(6-7):1303-1310
Summary Glycerol has been known as an important by-product of wine fermentations improving the sensory quality of wine. This study
was carried out with an endogenic wine yeast strain Saccharomyces cerevisiae Kalecik 1. The kinetics of growth and glycerol biosynthesis were analysed at various initial concentrations of glucose, fructose,
and sucrose in a batch system. Depending on the determined values of Monod constants, glucose (Ks = 28.09 g/l) was found as the most suitable substrate for the yeast growth. Initial glucose, fructose and sucrose concentrations
necessary for maximum specific yeast growth rate were determined as 175 g, 100 l, and 200 g/l, respectively. The yeast produced
glycerol at very high concentrations in fructose medium. Fructose was determined as the most suitable substrate for glycerol
production while the strain showed low tendency to use it for growth. S. cerevisiae Kalecik 1 could not produce glycerol below 200 g/l initial sucrose concentration. When natural white grape juice was used
as fermentation medium, maximum glycerol concentration and dry weight of the yeast were determined as 9.3 g/l and 11.8 g/l,
respectively. 相似文献
3.
Production of R-3-hydroxybutyric acid (3HB) was observed when genes of β-ketothiolase (PhbA), acetoacetyl CoA reductase (PhbB), and thioesterase
II (TesB) were jointly expressed in Escherichia coli. TesB, generally regarded as a medium chain length acyl CoA thioesterase, was found, for the first time, to play an important
role for transforming short chain length 3-hydroxybutyrate-CoA to its free fatty acid, namely, 3HB. E. coli BW25113 (pSPB01) harboring phbA, phbB, and tesB genes produced approximately 4 g/l 3HB in shake flask culture within 24 h with glucose used as a carbon source. Under anaerobic
growth conditions, 3HB production was found to be more effective, achieving 0.47 g 3HB/g glucose compared with only 0.32 g
3HB/g glucose obtained from aerobic process. When growth was conducted on sodium gluconate, 6 g/l 3HB was obtained. In a 24-h
fed-batch growth process conducted in a 6-l fermentor containing 3 l glucose mineral medium, 12 g/l 3HB was produced from
17 g/l cell dry weight (CDW). This was the highest 3HB productivity achieved by a one-stage fermentation process for 3HB production.
Liu and Ouyang contributed equally to the paper. 相似文献
4.
Anita Tocaj Anne Hof Per Hagander Olle Holst 《Applied microbiology and biotechnology》1993,38(4):463-466
Pseudomonas cepacia was cultivated on salicylate as sole carbon and energy source in a fed-batch culture. On-line measurement of salicylate concentration was carried out using a filtration system. Cell-free permeate was passed through a flow-through spectrophotometer. Measurements were carried out at 325 nm. A Proportional-Integral controller was used for regulating the feed rate around a basic dosage scheme to maintain a constant salicylate concentration of 0.2 g/l in the broth. The cell mass concentration increased from less than 1 g dry weight (dw)/l to 12 g dw/l in less than 6 h, and the yield coefficient was 0.4 g dw/g salicylate. The intracellular enzymatic activity of salicylate hydroxylase was virtually unchanged during the fed-batch cultivation.
Correspondence to: A. Tocaj 相似文献
5.
Bärbel Hahn-Hägerdal Sissi Berner Kerstin Skoog 《Applied microbiology and biotechnology》1986,24(4):287-293
Summary Ethanol was produced from xylose, using the enzyme glucose isomerase (xylose isomerase) and Saccharomyces cerevisiae. The influence of aeration, pH, enzyme concentration, cell mass and the concentration of the respiratory inhibitor sodium azide on the production of ethanol and the formation of by-products was investigated. Anaerobic conditions at pH 6.0, 10 g/l enzyme, 75 g/l dry weight cell mass and 4.6 mM sodium azide were found to be optimal. Under these conditions theoretical yields of ethanol were obtained from 42 g/l xylose within 24 hours.In a fed-batch culture, 62 g/l ethanol was produced from 127 g/l xylose with a yield of 0.49 and a productivity of 1.35 g/l·h. 相似文献
6.
Astaxanthin production from the green alga Haematococcus pluvialis with different stress conditions 总被引:1,自引:0,他引:1
Beatriz Cordero Ana Otero Manuel Patiño Bertha O. Arredondo Jaime Fabregas 《Biotechnology letters》1996,18(2):213-218
Summary
Haematococcus pluvialis was induced to produce the astaxanthin pigment. A factorial design was carried out with three sodium acetate concentrations, 0.025, 0.05, 0.1 (g/l), and three NaCl concentrations (0.1, 0.2 and 0.4 %).The best conditions in algal culture for astaxanthin production were 0.2 % NaCl, 0.025 g/l sodium acetate and 0.05 g/l sodium acetate, each a 3.0, 1.83 and 1.78 % of astaxanthin, production in base to total dry weight, respectively. The higher astaxanthin production by bioreactor was 18.6 mg/l in the condition with 0.2 % NaCl. 相似文献
7.
Summary An amylolytic lactic acid producing Lactobacillus amylovorus produced 36 g/l of lactic acid in mixed cultures with L. casei without additional nutrients at 37 °C in 48 h, when barley flour concentration was 180 g/l (appr. 108 g/l starch) and barley malt quantity 0.8% of flour weight. This represented an improvement of up to 20% in comparison to the fermentation with L. amylovorus or L. casei alone. By simultaneous glucoamylase addition lactic acid production yield was about doubled. With L. casei the lactic acid yield was from 580 g in 72 h to 667 g in 144 h per kg barley flour. 相似文献
8.
G. Lidén A. Persson C. Niklasson L. Gustafsson 《Applied microbiology and biotechnology》1995,43(6):1034-1038
Anaerobic fermentation of glucose (20 g/l) by Saccharomyces cerevisiae CBS 8066 was studied in a chemostat (dilution rate = 0.05–0.25 h–1) at different concentrations of the nitrogen source (5.00 g/l or 0.36 g/l ammonium sulphate). The ethanol yield (g ethanol produced/g glucose consumed) was found to be higher and the glycerol yield (g glycerol formed/g glucose consumed) lower during nitrogen limitation than under carbon limitation. The biomass yield on ATP (g dry weight biomass produced/mol ATP consumed) was consequently found to be lower during nitrogen-limited conditions. 相似文献
9.
《Bioscience, biotechnology, and biochemistry》2013,77(5):946-947
The pH-stat fed-batch culture of Pseudomonas aeruginosa YPJ-80 was done to produce a rhamnolipid biosurfactant. With glucose as the sole carbon source, the final concentrations of cells and rhamnolipid biosurfactant obtained in 25 h were 25 g cell dry weight/l and 4.4 g/l, respectively. 相似文献
10.
The on-line measurement of the relevant parameters and the control conception for three production processes for fine chemicals by fermentation and biotransformation at the 15 m3 scale were developed. The models describe the bioprocesses which successfully result in fully automated manufacturing steps. Modelling also proved to be a valuable tool for a better insight into biochemical fundamentals of the processes. Moreover, proper use of data logging, modelling and process control was important for quality, since two processes were controlled on-line and quality relevant deviations were registered early. Finally, combining modelling with simulation, we could drastically reduce both development time and cost.List of Symbols
F l/h
flux
-
V l
volume
-
U
0 g/l
nicotinonitrile concentration influx
-
U g/l
actual nicotinonitrile concentration
-
q
ug/gh
specific educt (=nicotinonitrile) transformation rate
-
x g/l
biocatalyst concentration
-
p
0 g/l
nicotinamide concentration influx
-
p g/l
actual nicotinamide concentration
-
q
pg/gh
specific product (=nicotinamide) formation rate
-
k
parameter loss of activity
-
q
u, maxg/gh
max. specific educt transformation rate
-
K
ug/l
saturation constant for nicotinonitrile
-
K
ig/l
inhibition constant for nicotinonitrile
-
K
iig/l
inhibition constant for nicotinamide
-
MW
Ag/mol
molecular weight for nicotinonitrile
-
MW
Bg/mol
molecular weight for nicotinamide
-
NS
Nicotinic acid
- 6-HNS
6-Hydroxynicotinic acid
-
r
NS, 6HNS g/lh
6-HNS production rate
-
r
6HNS, X g/lh
biomass production rate
-
r
NS, 6HNS, max g/lh
max. 6-HNS production rate
-
S
NS g/l
actual NS concentration
-
K
S, NS g/l
saturation constant for NS
-
K
i, 6HNS g/l
inhibition constant for 6-HNS
-
K
o2 g/l
saturation constant for oxygen
-
r
6HNS, X, max g/lh
max. biomass production rate
-
S
6HNS g/l
actual 6-HNS concentration
-
K
ii, NS g/l
inhibition constant for NS
-
RQ mol/mol
respiration quotient
-
S
xylg/l
actual xylene concentration
-
K
i, xylg/
inhibition constant for xylene
-
K
i, DMPYg/
inhibition constant for 2,5-dimethylpyrazine
-
r
Xg/lh
biomass production rate
-
r
X, maxg/lh
max. biomass production rate
-
K
s, xylg/l
saturation constant for xylene
-
S
DMPYg/l
actual concentration of DMPY
-
K
i, MPCAg/
inhibition constant for MPCA
-
K
O2g/
saturation constant for oxygen
-
S
MPCAg/l
actual MPCA concentration
-
S
O2g/l
actual oxygen concentration
-
r
MPCAg/lh
MPCA production rate
-
r
MPCA, maxg/lh
max. MPCA production rate
-
k
lgl
inhibition constant for the intermediates
-
k
s, DMPYgl
saturation constant for DMPY 相似文献
11.
S. E. Vecht M. W. Platt Z. Er-El I. Goldberg 《Applied microbiology and biotechnology》1988,27(5-6):587-592
Summary The present study describes the growth of Pseudomonas putida cells (ATCC 33015) in batch and continuous cultures on two toxic substrates; toluene and m-toluic acid as sole carbon and energy sources. In fed-batch cultures on m-toluic acid up to 3.55 g cell dry weight/1 were achieved with a maximal specific growth rate (max) of 0.1 h-1. The average cellular yield was 1.42 g cell dry weight/g m-toluic acid utilized. When liquid toluene was added to shake-flask cultures in the presence of 0.7 g/1 m-toluic acid, the average cellular yield obtained was 1.3 g cell dry weight/g toluene utilized and the max was 0.13 h-1. Growth on toluene vapour in the presence of 0.7 g/l m-toluic acid in batch cultures resulted in a cellular yield of 1.28 g cell dry weight/g toluene utilized, with growth kinetics almost identical to those with liquid toluene (max liquid=0.13 h-1, max vapour=0.12 h-1). The maximal biomass concentration was 3.8 g cell dry weight/l, obtained in both cases after 100 h of incubation. Pseudomonas putida was grown in a chemostat initially on 0.7 g/l m-toluic acid and vapour toluene and then in the steady state on toluene as the sole source of carbon and energy. Toluene was added continuously to the culture as vapour with the inflowing airstream. Chemostat cultures could be maintained at steady state for several months on toluene. The maximal biomass concentration obtained in the chemostat culture was 3.2 g cell dry weight/l. The maximum specific growth rate was 0.13 h-1, with a cellular yield of 1.05 g cell dry weight/g toluene utilized. Approximately 70% of the toluene consumed was converted into biomass, and the remainder was converted to CO2 and unidentified byproducts. 相似文献
12.
Takahiro Suzuki Hiroyuki Deguchi Tsuneo Yamane Shoichi Shimizu Kunihiko Gekko 《Applied microbiology and biotechnology》1988,27(5-6):487-491
Summary To control molecular weight of poly--hydroxybutyric acid (PHB) produced in a fedbatch culture of Protomonas extorquens, the effects of cultural temperature, pH, molar ratio of methanol and ammonia, and concentration of methanol in the medium on polymerization were inverstigated. Change of methanol concentration affected average molecular weight of PHB. When the cultivation was carried out at 0.05 g/l of methanol, average molecular weight of PHB reached above 8×105. On the other hand, in the case of 32 g/l of methanol average molecular weight of PHB was less than 0.5×105. Although every sample had a wide molelcular weight distribution, it became possible to control voluntarily average molecular weight of PHB. 相似文献
13.
The main purpose of this study was to investigate the effects of benzo(a)pyrene (BaP) on seabass (Dicentrarchus labrax) juveniles using parameters at different levels of biological organization. Liver antioxidant status, BaP biotransformation and accumulation, growth, and behavior were determined in juveniles after 28 d exposure to BaP (1–16 μ g/l). Liver ethoxyresorufin O-deethylase increased in seabass exposed to 1–8 μ g/l of BaP. Liver glutathione S-transferases and catalase activities were significantly increased at 4 and 8 μ g/l, but a slight decrease was observed at the highest concentrations tested. Bile BaP metabolites were significantly different from the control group at 1 and 16 μ g/l BaP. Liver BaP metabolites and lipid peroxidation significantly increased at 8 and 16 μ g/l BaP. These results suggest that BaP metabolites' accumulation induces oxidative damage in seabass liver. Body weight and length increase were significantly reduced in fish exposed to BaP, with LOECs of 16 and 4 μ g/l, respectively. Food intake and swimming velocity were significantly decreased after exposure to BaP, with LOEC values of 16 and 8 μ g/l, respectively. Results suggest that at concentrations of BaP equal or higher than 8 μ g/l, the detoxification capacity decreases, an accumulation of liver BaP metabolites occurs causing lipid peroxidation, affecting growth and swimming capability of fish. 相似文献
14.
Summary An overflow filtration unit for cell recycle with Clostridium acetobutylicum was developed. A cellulose-triacetate ultrafiltration membrane with a cut-off volume of 20 000 MW was found to work best. C. acetobutylicum was grown in continuous culture under phosphate limitation (0.74 mM) at a pH value of 4.4 with cell recycle, the cell dry weight in the culture vessel reached 13.1 g/l at a dilution rate of D=0.10 h-1 and 37°C. 377 mM of glucose were fermented to 190 mM butanol, 116.2 mM acetone and 25.8 mM ethanol. Total acids were 47.6 mM. The butanol productivity was 1.41 g/l/h. At a dilution rate of 0.40 h-1 the butanol productivity was increased to 4.1 g/l/h but glucose consumption was decreased to 285 mM and butanol, acetone and ethanol production to 138.2, 97.5, 16.5 mM, respectively. 相似文献
15.
Daniel HJ Otto RT Binder M Reuss M Syldatk C 《Applied microbiology and biotechnology》1999,51(1):40-45
In order to produce sophorolipids from whey, thereby lowering the lactose content and biological oxygen demand, a two-step
batch cultivation process was developed including medium sterilization by filtration. In the first step, whey was sterilized
by a combination of crossflow and sterile filtration. Because the sophorolipid-producing yeast Candida bombicola ATCC 22214 was not able to use lactose as a carbon source directly, the oleaginous yeast Cryptococcus curvatus ATCC 20509 was grown on deproteinized whey concentrates (DWC). With 1: 1 diluted DWC-20, lactose was consumed as the carbon
source and biomass (24 g/l dry weight content) as well as single-cell oil (SCO, 10 g/l) were produced. The cultivation broth
was disrupted with a glass bead mill and it served as medium for growth (29 g cell dry mass/l) and sophorolipid production
(12 g/l) of the yeast C. bombicola.
Received: 29 July 1998 / Received revision: 5 October 1998 / Accepted: 11 October 1998 相似文献
16.
Rawia Zayed H. El-Shamy Strahil Berkov Jaume Bastida Carles Codina 《In vitro cellular & developmental biology. Plant》2011,47(6):695-701
Different concentrations of methyl jasmonate, spermine, casein hydrolysate, or progesterone combined with 16 mg/l 2 iP + 4 mg/l
naphthalene acetic acid (NAA) were investigated in order to obtain higher multiplication rate and growth of Hippeastrum vittatum bulbs in vitro on MS basal medium. The highest multiplication rate (8.2 bulbs/explant) was attained with 80 mg/l spermine, while the highest
bulb fresh weight (1.23 g/bulblet) was obtained with 4 mg/l methyl jasmonate. Progesterone at 20 mg/l or casein hydrolysate
at 2.0 g/l gave the highest leaf length (14.1 and 13.2 cm, respectively). So, it can be advised to use 80 mg/l spermine combined
with 16 mg/l 2 iP + 4 mg/l NAA to obtain the highest number of bulbs per explant with moderate leaf length and bulb fresh
weight. Chemical analysis showed alternations in the alkaloid type ratio and number of compounds in the bulbs treated with
methyl jasmonate (4 mg/l). 相似文献
17.
Summary The temperature induced intracellular production of the fused protein SpA-gal (protein A/-galactosidase) withE. coli was compared in batch and fed batch culture. By introducing fed batch cultivation a final cell dry weight of 77.0 g/l was achieved, as compared to 16.4 g/l in batch cultivation. The concentration of SpA-gal in the fed batch cultivation was very high, 19.2 g/l. This corresponded to 25% of the cell dry weight. 相似文献
18.
Summary Pullulan is a polysaccharide produced by Aureobasidium pullulans. In this study, the effect of pH on the molecular weight of pullulan was investigated. High concentration of pullulan was obtained when initial pH was 6. Pullulan having molecular weight of 500,000–600,000 was produced at initial pH of 3.0, while pullulan with molecular weight of 200,000–300,000 was produced at pH above 4.5. To obtain high molecular weight pullulan with high concentration, pH was initially controlled at pH 6, followed by pH shift from pH 6 to pH 3. Transition of pH at 2 days of fermentation was observed to be optimum. Higher molecular weight pullulan was also obtained when sucrose concentration was 50 g/l compared to the result obtained at initial sucrose concentration of 20 g/l. Sucrose concentration and pH of the fermentation broth seem to be important parameters in obtaining high molecular weight of pullulan. 相似文献
19.
Species of the genera Taphrina Fr. and Protomyces Unger were screened for the presence of carotenoid pigments and the sterols ergosterol and brassicasterol. All strains produced carotenoids in variable amounts: Taphrina: 0.3–39 g/g dry weight; Protomyces: 65–99 g/g dry weight. It was concluded that the tow genera cannot be separated on the basis of presence or absence of carotenoids. Thirty strains (24 species) of Taphrina produced brassicasterol as the principal sterol; twenty-one strains (17 species) did not form ergosterol. Only four isolates (4 species) produced ergosterol without formation of brassicasterol. Brassicasterol was the major sterol in 3 species of Protomyces, whereas ergosterol was absent. Brassicasterol is a rather unique sterol within the fungal kingdom and has hitherto not been found in the red yeasts. Therefore, this sterol is of taxonomic significance in contrast with ergosterol, which is widespread among fungi. 相似文献
20.
A resveratrol synthase gene was cloned from the peanut plant (Arachis hypogaea) by RT-PCR and was transformed into purple sweet potato (Ipomoea batatas) by Agrobacterium-mediated transformation. Stem sections were infected with bacterial solution of OD600 = 0.4 for 20 min and then cocultured for 2 days. Infected explants were cultured on MS media containing 50 mg/l kanamycin,
0.02 mg/l NAA and 1 mg/l 6-BA for bud induction or containing 75 mg/l kanamycin, 1.0 mg/l NAA and 0.1 mg/l 6-BA for root formation.
The bud and root induction rates were 37.5 and 25.0%, respectively. 105 regenerated plants were obtained, with 11 positive
plants by PCR and Southern blotting analyses. A high level of resveratrol glucoside (340 μg/g dry weight), but no resveratrol,
was detected in the transformed plants by HPLC. This study also provides a stable genetic transformation and plant regeneration
method for metabolic modification of purple sweet potato. 相似文献