scholarly journals BNC Biosynthesis with Increased Productivity in a Newly Designed Surface Air-Flow Bioreactor

2020 ◽  
Vol 10 (11) ◽  
pp. 3850
Author(s):  
Izabela Cielecka ◽  
Małgorzata Ryngajłło ◽  
Stanisław Bielecki

The application of bacterial cellulose (BNC) could be widely expanded if the production costs were reduced. This study aims to determine factors simultaneously affecting the yield and tensile strength of BNC in a newly designed surface air-flow bioreactor (SAF). For this purpose, a two-stage study was done. Firstly, the most important factors for high yield were determined based on the Plackett–Burman Design. Secondly, impact of the chosen variables on both responses was assessed in a wide range of factor values. The greatest influence on the yield and mechanical strength was proved for such factors as air-flow ratio, glucose concentration, and culture time. The productivity in a SAF bioreactor with controlled air-flow ratio was enhanced by 65%. In terms of mechanical properties, the stress of BNC membranes varied from 0.8 to 6.39 MPa depending on the culture conditions. The results of the performed tests make a useful basis for future optimizations.

2014 ◽  
Vol 668-669 ◽  
pp. 1550-1553 ◽  
Author(s):  
Chu Shu Zhang ◽  
Qin Zhao ◽  
Jian Xiong Feng ◽  
Jie Sun ◽  
Li Na Yu ◽  
...  

Single factor and Plackett-Burman design were used to determine the key environmental factors for Aspergillus flavus growth and aflatoxin production. The results showed that the key factors were culture time, moisture content. So Controling of moisture was crucial for Aflatoxin contamination prevention and control.


Author(s):  
Vibha Shukla ◽  
Suresh Chandra Phulara

Recent years have seen a remarkable increase in the non-natural production of terpenoids from microbial route. This is due to the advancements in synthetic biology tools and techniques, which have overcome the challenges associated with the non-native production of terpenoids from microbial hosts. Although, microbes in their native form have ability to grow in wide range of physicochemical parameters such as, pH, temperature, agitation, aeration etc; however, after genetic modifications, culture conditions need to be optimized in order to achieve improved titers of desired terpenoids from engineered microbes. The physicochemical parameters together with medium supplements, such as, inducer, carbon and nitrogen source, and cofactor supply not only play an important role in high-yield production of target terpenoids from engineered host, but also reduce the accumulation of undesired metabolites in fermentation medium, thus facilitate product recovery. Further, for the economic production of terpenoids, the biomass derived sugars can be utilized together with the optimized culture conditions. In the present mini-review, we have highlighted the impact of culture conditions modulation on the high-yield and high-specificity production of terpenoids from engineered microbes. Lastly, utilization of economic feedstock has also been discussed for the cost-effective and sustainable production of terpenoids.


2011 ◽  
Vol 343-344 ◽  
pp. 1172-1181
Author(s):  
Shi Chang Li ◽  
Hong Xia Liu ◽  
Shao Bin Gu ◽  
Min Wang ◽  
Zhao Yang Zhu ◽  
...  

The paper studied on parameters of ion implantation into lipid producing strain Rhodotorula glutinis and lipid extration technology. It was found that the strain had a higher positive mutation rate when the output power was 10keV and the dose of N+ implantation was 80×2.6×1013 ions/cm2. Then a high-yield mutant strain D30 was obtained and it’s lipid yield which was 3.10 g/L increased by 33.05% than that of the original. Additionally, statistically-based experimental designs were applied for the optimization of lipid extraction by acid-heating coupling ultrasonic technique. By a Plackett-Burman design, it was found that three factors, treatment time of HCl (p=0.036) , ultrasonic time (p=0.0105) and rate of extracting solution (VCHCl3:VCH3OH) (p=0.0105), had significant effect on lipid extraction. Subsequently, these significant factors were optimized using response surface methodology (RSM), and the optimized parameters of lipid extraction were as follows: 34 min for treatment time of HCl, 7.5 min for ultrasonic treating time, 1.9:1 for rate of extracting solution (VCHCl3:VCH3OH). Finally the fermentation characteristic of high-yield mutation strain D30 was studied, when fermentation time was 10 d, it’s lipid yield increased to 7.81 g/L


2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Chao Kang ◽  
Ting-Chi Wen ◽  
Ji-Chuan Kang ◽  
Ze-Bing Meng ◽  
Guang-Rong Li ◽  
...  

Cordycepin is one of the most important bioactive compounds produced by species ofCordyceps sensu lato, but it is hard to produce large amounts of this substance in industrial production. In this work, single factor design, Plackett-Burman design, and central composite design were employed to establish the key factors and identify optimal culture conditions which improved cordycepin production. Using these culture conditions, a maximum production of cordycepin was 2008.48 mg/L for 700 mL working volume in the 1000 mL glass jars and total content of cordycepin reached 1405.94 mg/bottle. This method provides an effective way for increasing the cordycepin production at a large scale. The strategies used in this study could have a wide application in other fermentation processes.


2007 ◽  
Vol 561-565 ◽  
pp. 375-378
Author(s):  
Takayuki Takasugi ◽  
Yasuyuki Kaneno

Dual two-phase intermetallic alloys composed of geometrically close packed (GCP) structures of Ni3Al(L12) and Ni3V(D022) containing Nb were investigated in terms of the microstructural evolution during low temperature annealing (aging) and the related mechanical properties. The eutectoid region, i.e. the prior Al phase (Ni solid solution) is composed of the lamellar-like structure consisting of Ni3Al(L12) and Ni3V(D022) phases. The lamellar-like structure tended to align along <001> direction and on {001} plane in the prior A1 phase (or the L12 phase). In a wide range of temperature, the dual two-phase intermetallic alloys showed high yield and tensile strength, and also reasonable tensile ductility, accompanied with ductile fracture mode.


2019 ◽  
Vol 13 (1) ◽  
pp. 41-54
Author(s):  
Fuad G. Torizal ◽  
Ikki Horiguchi ◽  
Yasuyuki Sakai

Human Pluripotent Stem Cells (PSCs) are a valuable cell type that has a wide range of biomedical applications because they can differentiate into many types of adult somatic cell. Numerous studies have examined the clinical applications of PSCs. However, several factors such as bioreactor design, mechanical stress, and the physiological environment have not been optimized. These factors can significantly alter the pluripotency and proliferation properties of the cells, which are important for the mass production of PSCs. Nutritional mass transfer and oxygen transfer must be effectively maintained to obtain a high yield. Various culture systems are currently available for optimum cell propagation by maintaining the physiological conditions necessary for cell cultivation. Each type of culture system using a different configuration with various advantages and disadvantages affecting the mechanical conditions in the bioreactor, such as shear stress. These factors make it difficult to preserve the cellular viability and pluripotency of PSCs. Additional limitations of the culture system for PSCs must also be identified and overcome to maintain the culture conditions and enable large-scale expansion and differentiation of PSCs. This review describes the different physiological conditions in the various culture systems and recent developments in culture technology for PSC expansion and differentiation.


2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Rayda Siala ◽  
Fakher Frikha ◽  
Samiha Mhamdi ◽  
Moncef Nasri ◽  
Alya Sellami Kamoun

Medium composition and culture conditions for the acid protease production byAspergillus nigerI1 were optimized by response surface methodology (RSM). A significant influence of temperature, KH2PO4, and initial pH on the protease production was evaluated by Plackett-Burman design (PBD). These factors were further optimized using Box-Behnken design and RSM. Under the proposed optimized conditions, the experimental protease production (183.13 U mL−1) closely matched the yield predicted by the statistical model (172.57 U mL−1) withR2=0.914. Compared with the initial M1 medium on which protease production was 43.13 U mL−1, a successful and significant improvement by 4.25 folds was achieved in the optimized medium containing (g/L): hulled grain of wheat (HGW) 5.0; KH2PO41.0; NaCl 0.3; MgSO4(7H2O) 0.5; CaCl2(7H2O) 0.4; ZnSO40.1; Na2HPO41.6; shrimp peptone (SP) 1.0. The pH was adjusted at 5 and the temperature at30°C. More interestingly, the optimization was accomplished using two cheap and local fermentation substrates, HGW and SP, which may result in a significant reduction in the cost of medium constituents.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Xiujun Gao ◽  
Peisheng Yan ◽  
Xin Liu ◽  
Jianbing Wang ◽  
Jiajia Yu

To optimize the production conditions for exopolysaccharides with higher antioxidant activities fromXerocomus badiuscultured in shrimp byproduct medium, Plackett-Burman design, path of steepest ascent, and response surface methodology were explored. Based on the results of Plackett-Burman design and path of steepest ascent, a Box-Behnken design was applied to optimization and the regression models. The optimal cultural condition for high yield and antioxidant activity of the exopolysaccharides was determined to be 10.347% of solid-to-liquid ratio, a 4.322% content of bran powder, and a 1.217% concentration of glacial acetic acid. Culturing with the optimal cultural conditions resulted in an exopolysaccharides yield of4.588±0.346 g/L and a total antioxidant activity of2.956±0.105 U/mg. These values are consistent with the values predicted by the corresponding regression models (RSD < 5%).


2012 ◽  
Vol 518-523 ◽  
pp. 5578-5585
Author(s):  
Nan Ban ◽  
Yu Jie Zhou ◽  
Yan Ping Ye ◽  
Lin Mei Dai ◽  
Alatangaole Damirn ◽  
...  

Plackett-Burman design was employed for screening culture conditions for cellulase production by Penicillium decumbens in submerged fermentation. The results showed that wheat bran was the most significant factor influencing Filter Paper Activity (FPA) of the cellulase, followed by cellulose microcrystalline and initial pH, which could be further optimized for improving the cellulase activity. The effects of pH and temperature on FPA assay were investigated, and optimal FPA could be obtained at pH 4.5 and 60 °C. The stabilities of endo-glucanase (EG), exo-glucanase (CBH) and β-glucosidase (BG) were investigated and compared with that of FPA under different pH and temperature. The results indicated that CBH and FPA were more sensitive to pH and temperature than EG and BG and the stability of CBH was very similar to that of FPA under the conditions.


2020 ◽  
Author(s):  
Noura El-Ahmady El-Naggar ◽  
Nancy M. El-Shweihy

Abstract Background: Cholesterol oxidase biosensors have been used to determine the level of cholesterol in different serum and food samples. Due to a wide range of industrial and clinical applications of microbial cholesterol oxidase, isolation and identification of a new microbial source (s) of cholesterol oxidase are very important. Results: The local isolate Streptomyces sp. strain NEAE-94 is a promising source of cholesterol oxidase. It was identified based on cultural, morphological and physiological characteristics; in addition to the 16S rRNA sequence. The sequencing product had been deposited in the GenBank database under the accession number KC354803. Cholesterol oxidase production by Streptomyces anulatus strain NEAE-94 in shake flasks was optimized using surface response methodology. The different process parameters were first screened using a Plackett-Burman design and the parameters with significant effects on the production of cholesterol oxidase were identified. Out of the fifteen factors screened, agitation speed, cholesterol and yeast extract concentrations had the most significant positive effects on the production of cholesterol oxidase. The optimal levels of these variables and the effects of their mutual interactions on cholesterol oxidase production were determined using Box-Behnken design. Cholesterol oxidase production by Streptomyces anulatus strain NEAE-94 was 11.03, 27.31 U/mL after Plackett-Burman Design and Box-Behnken design; respectively, with a fold of increase of 6.06 times compared to the production before applying the Plackett-Burman design (4.51 U/mL). Conclusions: Maximum cholesterol oxidase activity is obtained at the following fermentation conditions: g/L (cholesterol 4, yeast extract 5, NaCl 0.5, K 2 HPO 4 1, FeSO 4 .7H 2 O 0.01, MgSO 4 .7H 2 O 0.5), pH 7, inoculum size 4 % (v/v), temperature 37°C, agitation speed 150 rpm, medium volume 50 mL and incubation time 5 days.


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