scholarly journals Efficient Expression of Maltohexaose-Forming α-Amylase from Bacillus stearothermophilus in Brevibacillus choshinensis SP3 and Its Use in Maltose Production

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Zhu Li ◽  
Lingqia Su ◽  
Xuguo Duan ◽  
Dan Wu ◽  
Jing Wu
Keyword(s):  
Culture Medium ◽  
Bacillus Stearothermophilus ◽  
Corn Starch ◽  
Expression System ◽  
Initial Ph ◽  
Brevibacillus Choshinensis ◽  
Efficient Expression ◽  
Cellular Integrity ◽  
Maltose Syrup ◽  
Starch Industry

The maltohexaose-forming, Ca2+-independent α-amylase gene from Bacillus stearothermophilus (AmyMH) was efficiently expressed in Brevibacillus choshinensis SP3. To improve the production of AmyMH in B. choshinensis SP3, the temperature and initial pH of culture medium were optimized. In addition, single-factor and response surface methodologies were pursued to optimize culture medium. Addition of proline to the culture medium significantly improved the production of recombinant α-amylase in B. choshinensis SP3. This improvement may result from improved cellular integrity of recombinant B. choshinensis SP3 in existence of proline. Culture medium optimization resulted in an 8-fold improvement in α-amylase yield, which reached 1.72 × 104 U·mL−1. The recombinant α-amylase was applied to the production of maltose on a laboratory scale. A maltose content of 90.72%, which could be classified as an extremely high maltose syrup, could be achieved using 15% (m/v) corn starch as the substrate. This study demonstrated that the B. choshinensis SP3 expression system was able to produce substantial quantities of recombinant α-amylase that has potential application in the starch industry.

Flocculating Activity Optimization of Lactobacillus paracasei subsp.paracasei L1 in Corn Liquid

2013 ◽  
Vol 850-851 ◽  
pp. 1172-1175
Author(s):  
Xiao Na Li ◽  
Xin Hua Li ◽  
Li Li Zhang ◽  
Jing Mu
Keyword(s):  
Culture Medium ◽  
Corn Starch ◽  
Culture Conditions ◽  
Lactobacillus Paracasei ◽  
Analysis Method ◽  
Medium Ph ◽  
Inoculum Concentration ◽  
Flocculating Activity ◽  
Initial Ph ◽  
Surface Analysis Method

In order to improve the production process of corn starch and accelerate the separation of corn starch, flocculating activity of lactobacillus paracasei subsp.paracasei L1 isolated from natural fermentation of sweet potato acid liquor in corn liquid was optimized. The main influencing factors were determined by Plackett-Burman experimental design and the flocculating activity was optimized by response surface analysis method. The optimum culture conditions was: inoculum concentration 18%, lactose addition 0.2%, corn steeping time 0h, culture temperature 30°C, initial pH of the culture medium pH 6.5, culture time 36h, yeast extract addition 1%,concentration of corn thick liquid 1:3(w/v).The theoretical value of the flocculating activity was 0.1906 mg/ml and the verified value was 0.1854 mg/ml.

Obtaining and purification of lysostaphin secreted in the culture liquid by Brevibacillus choshinensis/pNCMO2/lsf12 recombinant strain

2020 ◽  
Vol 36 (1) ◽  
pp. 7-15
Author(s):  
E.V. Baranova ◽  
V.V. Levchuk ◽  
T.V. Reshetnyak ◽  
P.V. Soloviev ◽  
N.A. Shishkova ◽  
...  
Keyword(s):  
Culture Medium ◽  
Expression System ◽  
Culture Liquid ◽  
Exchange Chromatography ◽  
High Yield ◽  
Diagnostic Tools ◽  
Yield Production ◽  
Brevibacillus Choshinensis ◽  
The Russian Federation ◽  
High Output

Here, «host-vector» expression system of Brevibacillus choshinensis was developed and used for producing a recombinant lysostaphin with high-output. The recombinant plasmid pNCMO2/lsf12 was constructed, and its expression in Brevibacillus choshinensis (strain Brevibacillus choshinensis/pNCMO2/lsf12) provided a synthesis of the 27-kDa protein, which was secreted into the culture medium. Its specific staphylolitic activity being 557 U/mg at optimal pH (7.5-8.0) and temperature (50-55 °C) values was comparable with the natural and recombinant analogs. We hope that developed methods of a deep cultivation of the recombinant Brevibacillus choshinensis/pNCMO2/lsf12 strain for a high-yield production (up to 90 mg/L) and a single-stage purification of lysostaphin (up to 90% homogeneity) become the basis for the production of the enzyme on an industrial scale. Brevibacillus choshinensis, ion-exchange chromatography, lysostaphin The work was financially supported by the Grant No. 050 of Rospotrebnadzor «Monitoring of borreliosis pathogens circulation in regions of the Russian Federation and improvement of diagnostic tools for borreliosis»

OBSERVATIONS ON AMYLOLYTIC BACTERIA: III. CULTURAL CONDITIONS INFLUENCING THE BREAKDOWN OF STARCH BY STENOTHERMOPHILIC BACTERIA BELONGING TO BACILLUS STEAROTHERMOPHILUS

1952 ◽  
Vol 30 (4) ◽  
pp. 360-370 ◽  
Author(s):  
Egon Stark ◽  
P. A. Tetrault
Keyword(s):  
Yeast Extract ◽  
Bacillus Stearothermophilus ◽  
Soluble Starch ◽  
The Other ◽  
Ph Changes ◽  
Proteose Peptone ◽  
Cultural Conditions ◽  
Initial Ph ◽  
Commercial Medium ◽  
Agar Media

Thirty-five cultures of Bacillus stearothermophilus hydrolyzed five starches under various cultural conditions. Hydrolysis occurred regardless of the type, brand, or batch of starch; regardless of the initial pH or of the subsequent pH changes of the medium. Starch in broth was better attacked than in agar media. Some cultures hydrolyzed 0.5%, but not 1% starch; others hydrolyzed easily 10% soluble starch. Length of incubation was important. Certain cultures never formed acid or sugar from starch. Dextrinization was a more reliable indication of starch hydrolysis than was the formation of acid or sugar. Soluble starch gave more consistent results in repeated experiments than did nonsoluble starches. The type of protein medium determines strongly the formation of amylase. Trypticase was the best commercial medium, yeast extract came second. The other 10 media yielded fewer amylolytic cultures. Yeast extract added to media enhanced amylase formation, except with trypticase. Tryptose, proteose-peptone, and neopeptone inhibited the growth of most cultures.

scholarly journals Data-driven Modelling of Microfiltration Process with Embedded Static Mixer for Steepwater from Corn Starch Industry

2017 ◽  
Author(s):  
Laslo Šereš ◽  
Ljubica Dokić ◽  
Bojana Ikonić ◽  
Dragana Šoronja-Simović ◽  
Miljana Djordjević ◽  
...  
Keyword(s):  
Corn Starch ◽  
Desirability Function ◽  
Specific Energy Consumption ◽  
Cross Flow ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Static Mixer ◽  
Permeate Flux ◽  
Experimental Conditions ◽  
Starch Industry

Cross-flow microfiltration using ceramic tubular membrane was applied for treatment of steepwater from corn starch industry. Experiments are conducted according to the faced centered central composite design at three different transmembrane pressures (1, 2 and 3 bar) and cross-flow velocities (100, 150 and 200 L/h) with and without the usage of Kenics static mixer. For examination of the influence of the selected operating conditions at which usage of the static mixer is justified, a response surface methodology and desirability function approach were used. Obtained results showed improvement in the average permeate flux by using Kenics static mixer for 211 % to 269 % depending on experimental conditions when compared to the system without the static mixer. As a result of optimization, the best results considering flux improvement as well as reduction of specific energy consumption were obtained at low transmembrane pressure and lower feed cross-flow rates.

Study on Optimization of Fermentation Condition for Nitrilase-Producer Escherichia Coli BL21 (DE3)/pET-Nit

2011 ◽  
Vol 175-176 ◽  
pp. 192-196 ◽  
Author(s):  
Li Li Feng ◽  
Jian Fei Zhang ◽  
Hui Luo ◽  
Zheng Li ◽  
Hong Jie Zhang
Keyword(s):  
Escherichia Coli ◽  
Recombinant Strain ◽  
Culture Medium ◽  
Culture Conditions ◽  
Fermentation Condition ◽  
Hydrogen Phosphate ◽  
Strain Bl21 ◽  
Initial Ph ◽  
Potassium Hydrogen ◽  
Optimization Of Fermentation

The paper concentrated on the optimization of the recombinant strain BL21 (DE3)-PE7-Nit. The component of culture medium and the culture conditions were optimized. The optimized medium was: yeast extract 10 g/l, L-glutamate sodium 8 g/l, MgSO4.7H2O 0.7 g/l, Isopropyl-β-D-thiogalactopyranoside 0.3 mmol/L, potassium hydrogen phosphate 0.5 g / L, phosphate Potassium 0.5 g / L and the culture condition was: initial pH 7.0, inoculum 2%. The result showed that the activity of nitrilase prepared with these conditions increased by 130.37 % through optimization.

scholarly journals The Characteristics of Acetobacter xylinum Membrane Affected by pH of Culture Medium

2019 ◽  
Vol 9 (1) ◽  
pp. 5873-5878
Keyword(s):  
Morphological Analysis ◽  
Culture Medium ◽  
Acetobacter Xylinum ◽  
Membrane Properties ◽  
X Ray Diffraction ◽  
Vapour Permeability ◽  
X Ray ◽  
Initial Ph ◽  
Suitable Amount ◽  
Ph Level

There are numerous previous studies working on biosynthesis, properties and applications of bacterial cellulose (BC) membrane from Acetobacter xylinum bacteria strain. However, there is less research examining the effect of initial pH level on BC membrane properties. Here, BC membranes were produced at different pH level (concentration of acetic acid) of coconut water-based culture medium which are 3.5, 4.0, 4.5, 5.0 and 5.5 for 7 days, statically. The effect of initial pH level during BC production on morphology, physical and characteristics were investigated. The Acetobacter xylinum membrane were studied its crystallinity using X-ray diffraction, FTIR analysis for chemical structure and FESEM for morphological analysis. In addition, the different of initial pH level does affect the membrane yield and breathability properties using an Upright Cup Method of water vapour permeability testing. Although certain suitable amount of acid had reduced the production yield, a breathable BC membrane was produced.

scholarly journals Heterologous Expression of a Thermostable α-Glucosidase from Geobacillus sp. Strain HTA-462 by Escherichia coli and Its Potential Application for Isomaltose–Oligosaccharide Synthesis

Molecules ◽  
2019 ◽  
Vol 24 (7) ◽  
pp. 1413
Author(s):  
Fan Zhang ◽  
Weiyang Wang ◽  
Fatoumata Binta Maci Bah ◽  
Chengcheng Song ◽  
Yifa Zhou ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Enzymatic Synthesis ◽  
Bacillus Stearothermophilus ◽  
Maximal Activity ◽  
Oligosaccharide Synthesis ◽  
Optimum Temperature ◽  
Divalent Ions ◽  
Food Ingredients ◽  
Shake Flasks ◽  
Maltose Syrup

Isomaltose–oligosaccharides (IMOs), as food ingredients with prebiotic functionality, can be prepared via enzymatic synthesis using α-glucosidase. In the present study, the α-glucosidase (GSJ) from Geobacillus sp. strain HTA-462 was cloned and expressed in Escherichia coli BL21 (DE3). Recombinant GSJ was purified and biochemically characterized. The optimum temperature condition of the recombinant enzyme was 65 °C, and the half-life was 84 h at 60 °C, whereas the enzyme was active over the range of pH 6.0–10.0 with maximal activity at pH 7.0. The α-glucosidase activity in shake flasks reached 107.9 U/mL and using 4-Nitrophenyl β-D-glucopyranoside (pNPG) as substrate, the Km and Vmax values were 2.321 mM and 306.3 U/mg, respectively. The divalent ions Mn2+ and Ca2+ could improve GSJ activity by 32.1% and 13.8%. Moreover, the hydrolysis ability of recombinant α-glucosidase was almost the same as that of the commercial α-glucosidase (Bacillus stearothermophilus). In terms of the transglycosylation reaction, with 30% maltose syrup under the condition of 60 °C and pH 7.0, IMOs were synthesized with a conversion rate of 37%. These studies lay the basis for the industrial application of recombinant α-glucosidase.

scholarly journals Evaluation of the process conditions for the production of microbial carotenoids by the recently isolated Rhodotorula mucilaginosa URM 7409

2019 ◽  
Vol 22 ◽  
Author(s):  
Whallans Raphael Couto Machado ◽  
Lucas Gomes da Silva ◽  
Ellen Silva Lago Vanzela ◽  
Vanildo Luiz Del Bianchi
Keyword(s):  
Experimental Design ◽  
Yeast Extract ◽  
Culture Medium ◽  
Nitrogen Sources ◽  
Process Conditions ◽  
Malt Extract ◽  
Rhodotorula Mucilaginosa ◽  
Process Characteristics ◽  
Initial Ph ◽  
Microbial Carotenoids

Abstract This study aimed to improve the physical and nutritional process conditions for the production of carotenoids by the newly isolated Rhodotorula mucilaginosa, a red basidiomycete yeast. The carotenoid bioproduction was improved using an experimental design technique, changing the process characteristics of agitation (130 rpm to 230 rpm) and temperature (25 °C to 35 °C) using seven experiments, followed by a 25-1 fractional design to determine the relevant factors that constitute the culture medium (glucose, malt extract, yeast extract, peptone and initial pH). A complete second order experimental design was then carried out to optimize the composition of the culture medium, the variables being yeast extract (0.5 to 3.5 g/L), peptone (1 to 5 g/L) and the initial pH (5.5 to 7.5), with 17 experiments. The maximum carotenoid production was 4164.45 μg/L (252.99 μg/g), obtained in 144 h in YM (yeast malt) medium with 30 g/L glucose, 10 g/L malt extract, 2 g/L yeast extract, 3 g/L peptone, an initial pH 6, 130 rpm and 25 °C, demonstrating the potential of this yeast as a source of bio-pigments. In this work, the nitrogen sources were the factors that most influenced the intracellular accumulation of carotenoids. The yeast R. mucilaginosa presented high production at a bench level and may be promising for commercial production.

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