共查询到20条相似文献,搜索用时 31 毫秒
1.
M. Vidyasagar S. Prakash S. K. Jayalakshmi K. Sreeramulu 《World journal of microbiology & biotechnology》2007,23(5):655-662
An extremely halophilic Chromohalobacter sp. TVSP101 was isolated from solar salterns and screened for the production of extracellular halothermophilic protease.
Identification of the bacterium was done based upon biochemical tests and the 16S rRNA sequence. The partially purified enzyme
displayed maximum activity at pH 8 and required 4.5 M of NaCl for optimum proteolytic activity. In addition, this enzyme was
thermophilic and active in broad range of temperature 60–80°C with 80°C as optimum. The Chromohalobacter sp. required 4 M NaCl for its optimum growth and protease secretion and no growth was observed below 1 M of NaCl. The initial
pH of the medium for growth and enzyme production was in the range 7.0–8.0 with optimum at pH 7.2. Various cations at 1 mM
concentration in the growth medium had no significant effect in enhancing the growth and enzyme production but 0.5 M MgCl2 concentration enhanced enzyme production. Casein or skim milk powder 1% (w/v) along with 1% peptone proved to be the best
nitrogen sources for maximum biomass and enzyme production. The carbon sources glucose and glycerol repressed the protease
secretion. Immobilization of whole cells in absence of NaCl proved to be useful for continuous production of halophilic protease. 相似文献
2.
Gluconobacter oxydans that produces the cellulose was isolated. In order to confirm the chemical features of cellulose, various spectrophtometeric
analysis were carried out using electron microscopy, X-ray diffractogram, and CP/MAS13C NMR. The purified cellulose was found to be identical to that ofAcetobacter xylinum. For effective production of cellulose, the various carbon and nitrogen sources, mixture of calcium and magnesium ions, and
biotin concentration were investigated in flask cultures. Among the various carbon sources, glucose and sucrose were found
to be best for the production of cellulose, with maximum concentration of 2.41 g/L obtained when a mixture of 10 g/L of each
glucose and sucrose were used. With regard to the nitrogen sources, when 20 g/L of yeast extract was used, the maximum concentration
of bacterial cellulose was reached. The concentration of cellulose was increased with mixture of 2 mM of each Ca2+ and Mg2+. The optimum biotin concentration for the production of cellulose was in the range of 15 to 20 mg/L. At higher biotin concentration
(25–35 mg/L), the bacterial cellulose production was lower. 相似文献
3.
Beata Kluczek-Turpeinen Pekka Maijala Marja Tuomela Martin Hofrichter Annele Hatakka 《World journal of microbiology & biotechnology》2005,21(8-9):1603-1609
Summary Paecilomyces inflatus isolated from municipal waste compost was found to have cellulolytic activity in several solid and liquid media. This study
was done to reveal the multifarious effects of municipal waste compost on endoglucanase activity of P. inflatus. The highest enzyme activities under the conditions of solid-state fermentation were measured in authentic compost samples
compared with wood, straw and bran substrates. In surface liquid cultures glucose, cellobiose, xylan, Avicel cellulose, carboxymethylcellulose
(CM-cellulose), starch and citrus pectin were used as carbon sources. All carbon sources supported the growth of P. inflatus. However, only CM-cellulose, cellobiose and pectin noticeably stimulated endoglucanase (EG) activity. Further stimulation
of EG activity was obtained in cultures containing 1% CM-cellulose as a carbon source by supplementation with low-molecular
mass aromatic compounds vanillin, veratric acid and benzoic acid, and with soil humic acid (SHA). SHA and veratric acid were
found to be the most efficient elicitors of the cellulolytic activity. P. inflatus was able to utilize nitrate and ammonium as pure nitrogen sources in media containing cellulose. 相似文献
4.
Nona Mikiashvili Solomon P. Wasser Eviatar Nevo Vladimir Elisashvili 《World journal of microbiology & biotechnology》2006,22(9):999-1002
Summary The effect of various carbon and nitrogen sources on laccase, manganese-dependent peroxidase (MnP), and peroxidase production by two strains of Pleurotus ostreatus was investigated. The maximal laccase yield of P. ostreatus 98 and P. ostreatus 108 varied depending upon the carbon source from 5 to 62 U l−1 and from 55 to 390 U l−1, respectively. The highest MnP and peroxidase activities were revealed in medium supplemented by xylan. Laccase, MnP, and peroxidase activities of mushrooms decreased with supplementation of defined medium by inorganic nitrogen sources. Peptone followed by casein hydrolysate appeared to be the best nitrogen sources for laccase accumulation by both fungi. However, their positive effects on enzyme accumulation were due to a higher biomass production. The secretion of MnP and peroxidase by P. ostreatus 108 was stimulated with supplementation of casein hydrolysate to the control medium since the specific MnP and peroxidase activities increased 15-fold and 3.5-fold, respectively. 相似文献
5.
Gunashree BS Venkateswaran G 《Journal of industrial microbiology & biotechnology》2008,35(12):1587-1596
The present article deals with the studies on the effect of media ingredients, such as carbon, nitrogen, inorganic phosphates,
surfactants, and metal salts, on phytase enzyme production by Aspergillus niger CFR 335 in submerged (SmF) and solid-state fermentations (SSF). The results obtained showed a 1.5-fold higher enzyme yield
in the presence of sucrose in both SmF and SSF, while peptone was found to be a favorable nitrogen source for SmF. Sodium
dihydrogen phosphate (NaH2PO4) favored 34% higher enzyme yield than the control, which was followed by 19% higher activity in potassium dihydrogen phosphate
(KH2PO4) in SSF at 0.015% w/v. The addition of Tween-20 in SmF showed a maximum yield of 12.6 U/mL while, SDS suppressed the growth
of the fungus. None of the surfactants favored the enzyme yield in SSF. Calcium chloride (CaCl2) was extensively efficient in stimulating more than 55% higher phytase production in SmF at 0.01% v/v. In SSF, none of the
metal salts stimulated phytase production. 相似文献
6.
Ginalska G Bancerz R Korniłłowicz-Kowalska T 《Journal of industrial microbiology & biotechnology》2004,31(4):177-182
Growth and production of lipase by a new Geotrichum-like strain, R59, were studied. Production of extracellular lipase was substantially enhanced when the initial pH of the culture medium, types of carbon and nitrogen sources, substances probably stimulating the lipase biosynthesis, the temperature, and time of growth were optimized. Sucrose and triolein were the most effective carbon sources for lipase production. Maximum lipase activity (146 U/ml–1) was obtained with urea as the nitrogen source. Growth at 30°C, an initial pH of 6.0 and incubation time of 48 h were found as optimum conditions for cell growth and production of lipase by Geotrichum-like strain R59. The enzyme was thermostable and exhibited very high activity after 1 h incubation at 60°C. 相似文献
7.
The objective of the present study was to measure the production of cutinase by Fusarium oxysporum in the presence of several carbon and nitrogen sources (glycides, fatty acids and oils, and several organic and inorganic
nitrogen sources), trying to find a cost-effective substitute for cutin in the culture medium as an inducer of cutinase production.
The results were evaluated by the Tukey test, and flaxseed oil was found to give the best results as a cutinase inducer. The
authors optimized the composition of the growth medium employing response surface methodology. The experimental results were
fitted to a second-order polynomial model at a 95% level of significance (p < 0.05). The greatest cutinolytic activity was obtained in a liquid mineral medium supplemented with flaxseed oil, showing
an increase in enzymatic activity from 11 to 22.68 U/mL after 48 h of fermentation. A CCD study of the fermentation conditions
was carried out, and the best production of cutinase was registered with the use of 30 °C and 100 rpm. These results support
the use of flaxseed oil as a substitute for cutin, which is difficult and expensive to obtain, for the production of cutinase
in a larger scale. 相似文献
8.
Iturin A, a lipopeptide antibiotic produced by Bacillus subtilis RB14-CS, suppresses the growth of various plant pathogens. Here, enhancement of iturin A production in solid-state fermentation
(SSF) on okara, a soybean curd residue produced during tofu manufacturing, was accomplished using statistical experimental
design. Primary experiments showed that the concentrations of carbon and nitrogen sources were the main factors capable of
enhancing iturin A production, whereas initial pH, initial water content, temperature, relative humidity, and volume of inoculum
were only minor factors. Glucose and soybean meal were the most effective among tested carbon and nitrogen sources, respectively.
Based on these preliminary findings, response surface methodology was applied to predict the optimum amounts of the carbon
and nitrogen sources in the medium. The maximum iturin A concentration was 5,591 μg/g initial wet okara under optimized condition.
Subsequent experiments confirmed that iturin A production was significantly improved under the predicted optimal medium conditions.
The SSF product generated under the optimized conditions exhibited significantly higher suppressive effect on the damping-off
of tomato caused by Rhizoctonia solani K-1 compared with the product generated under the non-optimized conditions. 相似文献
9.
The production of extracellular cellulases by a newly isolated thermoacidophilic fungus, Aspergillus terreus M11, on the lignocellulosic materials was studied in solid-state fermentation (SSF). The results showed that the high-level cellulase activity was produced at 45 degrees C pH 3 and moisture 80% with corn stover and 0.8% yeast extract as carbon and nitrogen sources. 581 U endoglucanase activity, 243 U filter paper activity and 128 U beta-glucosidase activity per gram of carbon source were obtained in the optimal condition. Endoglucanase and beta-glucosidase exhibited their maximum activity at pH 2 and pH 3, respectively, and both of them showed remarkable stability in the range of pH 2-5. The activities of endoglucanase and beta-glucosidase were up to the maximum at 70 degrees C and maintained about 65% and 53% of their original activities after incubation at 70 degrees C for 6h. The enzyme preparations from this strain were used to hydrolyze Avicel. Higher hydrolysis yields of Avicel were up to 63% on 5% Avicel (w/v) for 72 h with 20 U FPase/g substrate. 相似文献
10.
The carbon and nitrogen source requirements of Aspergillus fumigatus NRRL 2436 for growth and production of the angiogenesis inhibitor fumagillin were studied in chemically defined media. Both
carbon and nitrogen sources strongly influenced fumagillin formation. Two out of 29 carbon sources tested interfered with
fumagillin biosynthesis. The best combination of two carbon sources was 30 g L−1 xylan and 50 g L−1 mannose. Of fifteen nitrogen sources tested, three ammonium salts (chloride, sulfate, and dibasic phosphate) failed to support
fumagillin formation, presumably due to the low pH which developed. The dosage-response study of the best nitrogen source,
L-glutamic acid, revealed that 9 g L−1 was optimal. Volumetric production of fumagillin was increased by 15-fold over that in the starting (Peterson-Goldstein)
medium as a result of these findings.
Received: 8 April 2002 / Accepted: 24 June 2002 相似文献
11.
Glucose alone was found to be the most effective carbon source for producing compactin. An initial glucose concentration of
40 g/L gave the highest compactin concentration of 250 mg/L. Among the various nitrogen sources, when 5 g/L of pharmamedia
and soybean meal as the sole nitrogen source were used, respectively, the compactin concentration was higher than 250 mg/L.
Especially, in the case of the mixture of 6 g/L of pharmamedia and 8 g/L of soybean meal, the compactin concentration was
400 mg/L. To select the best surfactant for effective compactin production, various surfactants were investigated. When Triton
X-100 was used, the maximum compactin concentration was 445 mg/L. With the initial concentration ranging from 1.5 to 2.0 g/L,
the compactin concentration was the highest at 465–450 g/L. The cell concentration was similar to that of the control without
the addition of Triton X-100. On the other hand, when the above 4.0 g/L of Triton X-100 were used, the cell concentration
decreased. Using the based results the continuous fed-batch cultures by adding the Triton X-100 were carried out for 10 days
in an air-lift bioreactor. When 1.5 g/L of Triton X-100 was added to the culture broth at 0, 4, and 8 days of culture, respectively,
the compactin production was increased with the increase of culture time. The maximum compactin concentration after 10 days
of culture was 1,200 mg/L, which was about 2.0-fold higher than that of the control without the addition of Triton X-100. 相似文献
12.
Summary A locally isolated strain of Aspergillus foetidus MTCC 4898 was studied for xylanase (EC 3.2.1.8) production using lignocellulosic substrates under solid state fermentation. Corncobs were found as the best substrates for high yield of xylanases with poor cellulase production. The influence of various parameters such as temperature, pH, moistening agents, moisture level, nitrogen sources and pretreatment of substrates were evaluated with respect to xylanase yield, specific activity and cellulase production. Influence of nitrogen sources on protease secretion was also examined. Maximum xylanase production (3065 U/g) was obtained on untreated corncobs moistened with modified Mandels and Strenberg medium, pH 5.0 at 1 5 moisture levels at 30 °C in 4 days of cultivation. Submerged fermentation under the same conditions gave higher yield (3300 U/g) in 5 days of cultivation, but productivity was less. Ammonium sulphate fractionation yielded 3.56-fold purified xylanase with 76% recovery. Optimum pH and temperature for xylanase activity were found to be 5.3 and 50 °C respectively. Kinetic parameters like Km and Vmax were found to be 3.58 mg/ml and 570 μmol/mg/min. Activity of the enzyme was found to be enhanced by cystiene hydrochloride, CoCl2, xylose and Tween 80, while significantly inhibited by Hg++, Cu++ and glucose. The enzyme was found to be stable at 40 °C. The half life at 50 °C was 57.53 min. However thermostability was enhanced by glycerol, trehalose and Ca++. The crude enzyme was stable during lyophilization and could be stored at less than 0 °C. 相似文献
13.
D. Mamma D. Hatzinikolaou D. Kekos H. Stamatis E. Kalogeris 《World journal of microbiology & biotechnology》2009,25(5):781-788
A thermostable endoglucanase (EndoI) was produced by the thermophilic fungus Thermoascus aurantiacus when grown on cellulosic materials under submerged culture (SC) and solid-state fermentation (SSF). In both cultivation techniques
a considerable amount of enzyme activity remained adsorbed onto solid particles, and this was taken into consideration when
modeling enzyme production. The results were compatible with the assumption that, following its synthesis, an amount of EndoI
was bound on substrate and gradually released into the liquid medium. Adsorption of the enzyme on crystalline cellulose was
confirmed in vitro by experiments with purified endoglucanase, which was isolated by anion exchange chromatography. The Langmuir
isotherm could efficiently describe the adsorption kinetics, and the estimated A
max and K
ad values compared with those obtained for cellulases bearing a binding domain. EndoI displayed high affinity for crystalline
cellulose and low binding capacity, which could be beneficial in textile processing. 相似文献
14.
Ramana K.V. Tomar A. Singh Lokendra 《World journal of microbiology & biotechnology》2000,16(3):245-248
The effect of various carbon and nitrogen sources on cellulose membrane production by Acetobacter xylinum was evaluated. Among the carbon sources, sucrose, glucose and mannitol were found to be suitable for optimum levels of cellulose production. The strain was able to utilize a wide range of protein and nitrogen sources such as peptone, soybean meal, glycine, casein hydrolysate, and glutamic acid for cellulose synthesis. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of pellicle proteins (PP) revealed electrophoretic bands of molecular masses in the range of 116–20 kDa. Furthermore, the strain can be useful for the removal of various nitrogenous and carbon substrates present in waste waters. 相似文献
15.
采用单因子相互比较法研究了不同碳素和氮素对彩绒革盖菌胞外漆酶,愈创木酚氧化酶,多酚氧化酶,锰过氧化物酶等木素降解酶分泌的影响,结果淀粉作碳源,干酪素作氮源有利于漆酶的分泌,麦芽粉作碳源,酵母膏作氮源有利于愈创木酚氧化酶和多酚氧化酶的分泌,淀粉作碳源,玉米粉作氮源有利于锰过氧化物酶的分泌。 相似文献
16.
Xueyun Wu Dong Yang Xiangcheng Zhu Zhiyang Feng Zhengbin Lv Yaozhou Zhang Ben Shen Zhinan Xu 《Biotechnology and Bioprocess Engineering》2010,15(4):664-669
The heterologous production of iso-migrastatin (iso-MGS) was successfully demonstrated in an engineered S. lividans SB11002 strain, which was derived from S. lividans K4-114, following introduction of pBS11001, which harbored the entire mgs biosynthetic gene cluster. However, under similar fermentation conditions, the iso-MGS titer in the engineered strain was
significantly lower than that in the native producer — Streptomyces platensis NRRL 18993. To circumvent the problem of low iso-MGS titers and to expand the utility of this heterologous system for iso-MGS
biosynthesis and engineering, systematic optimization of the fermentation medium was carried out. The effects of major components
in the cultivation medium, including carbon, organic and inorganic nitrogen sources, were investigated using a single factor
optimization method. As a result, sucrose and yeast extract were determined to be the best carbon and organic nitrogen sources,
resulting in optimized iso-MGS production. Conversely, all other inorganic nitrogen sources evaluated produced various levels
of inhibition of iso-MGS production. The final optimized R2YE production medium produced iso-MGS with a titer of 86.5 mg/L,
about 3.6-fold higher than that in the original R2YE medium, and 1.5 fold higher than that found within the native S. platensis NRRL 18993 producer. 相似文献
17.
Adhyayan Sharan Shikha Nandan S. Darmwal 《World journal of microbiology & biotechnology》2008,24(12):3087-3090
The phosphate solubilization activity of Xanthomonas campestris was measured in both the wild type and mutant strains using various carbon and nitrogen sources. Glucose was found to be
the best in both (wild 39.9%; mutant 67.1%) strains followed by sucrose (46.8%) in the mutant and molasses (36.0%) in the
wild type. Ammonium sulphate was the best nitrogen source for both the strains, followed by ammonium nitrate and urea. Dicalcium
phosphate (DCP) was solubilized maximally by both the strains followed by tricalcium phosphate (TCP) and rock phosphate (RP)
when various concentrations of different phosphate sources were tested. 相似文献
18.
Bettin F Montanari Q Calloni R Gaio TA Silveira MM Dillon AJ 《Journal of industrial microbiology & biotechnology》2009,36(1):1-9
Some conditions in media composition for laccases production, such as different sources of carbon and organic nitrogen, antifoams
and a surfactant, were studied in liquid cultures of Pleurotus sajor-caju strain PS-2001. Cultivation with fructose or glucose as carbon sources produced maximum enzyme activities of 37 and 36 U mL−1, respectively. When sucrose was present in the medium, the best results were obtained using 5 g L−1 of this carbohydrate, on the 11th day of the process, attaining laccase titres of 13 U mL−1. In a medium without casein, practically no enzyme was produced during the experiments; among the sources of nitrogen studied,
pure casein led to the highest titres of laccase activity. Different concentrations of pure casein and sucrose were also tested.
As to the different concentrations of casein, the addition of 1.5 g L−1 resulted in the highest titres of laccase activity. Negligible levels of manganese peroxidase activity were also detected
in the culture medium. In low concentrations, polypropylene glycol or silicon-based antifoams and the surfactant Tween 80
have no significant influence on the formation of laccases by P. sajor-caju. However, enhanced concentration of polypropylene glycol negatively affected the production of laccases but favored the titres
in total peroxidases, lignin peroxidase and veratryl alcohol oxidase. 相似文献
19.
Francisco José Mataix M. Josefa Fernández Manuel Ruiz Amil 《Archives of microbiology》1976,111(1-2):197-198
The regulation of ornithine transcarbamylase (OTC) of Rhodotorula glutinis has been studied, by growing the yeasts in different carbon and nitrogen sources and estimating the enzyme level in crude yeasts extracts.The results show a nutritional repression of OTC by arginine, when added to the culture media as carbon, nitrogen or carbon and nitrogen sources. On the other hand ornithine does not exert any effect in the same experimental conditions. 相似文献
20.
Ana Mendes Pedro Guerra Vânia Madeira Francisco Ruano Teresa Lopes da Silva Alberto Reis 《World journal of microbiology & biotechnology》2007,23(9):1209-1215
In this work, carob pulp syrup was used as carbon source in C. cohnii fermentations for docosahexaenoic acid production. In preliminary experiments different carob pulp dilutions supplemented
with sea salt were tested. The highest biomass productivity (4 mg/lh) and specific growth rate (0.04/h) were observed at the
highest carob pulp dilution (1:10.5 (v/v), corresponding to 8.8 g/l glucose). Ammonium chloride and yeast extract were tested
as nitrogen sources using different carob pulp syrup dilutions, supplemented with sea salt as growth medium. The best results
were observed for yeast extract as nitrogen source. A C. cohnii fed-batch fermentation was carried out using diluted carob pulp syrup (1:10.5 v/v) supplemented with yeast extract and sea
salt. The biomass productivity was 420 mg/lh, and the specific growth rate 0.05/h. Under these conditions the DHA concentration
and DHA production volumetric rate attained 1.9 g/l and 18.5 mg/lh respectively after 100.4 h. The easy, clean and safe handling
of carob pulp syrup makes this feedstock a promising carbon source for large-scale DHA production from C. cohnii. In this way, this carob industry by-product could be usefully disposed of through microbial production of a high value fermentation
product. 相似文献