scholarly journals Successive Nonstatistical and Statistical Approaches for the Improved Antibiotic Activity of Rare ActinomyceteNonomuraeasp. JAJ18

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Polpass Arul Jose ◽  
Solomon Robinson David Jebakumar
Keyword(s):  
Response Surface ◽  
Large Scale ◽  
Polynomial Regression ◽  
Antibiotic Production ◽  
Nitrogen Sources ◽  
Optimization Method ◽  
Antibiotic Activity ◽  
Media Optimization ◽  
Burman Design ◽  
Nutritional Constituents

The selection and optimization of nutritional constituents as well as their levels for the improved production of antibiotic byNonomuraeasp. JAJ18 were carried out using combination of both nonstatistical one-factor-at-a-time (OFAT) method and statistical response surface methodology (RSM). Using OFAT method, starch and (NH4)2SO4were identified as suitable carbon and nitrogen sources, respectively. Subsequently, starch, NaCl, and MgSO4·7H2O were recognized as the most significant media components with confidence level of above 95% using the Plackett-Burman design. The levels of the three media components were further optimized using RSM employed with Box-Behnken design. Accordingly, a second-order polynomial regression model was fitted into the experimental data. By analyzing the response surface plots as well as using numerical optimization method, the optimal levels for starch, NaCl, and MgSO4·7H2O were determined as 15.6 g/L, 0.8 g/L, and 1.98 g/L, respectively. With the optimized medium, 15.5% increase was observed in antibiotic activity of JAJ18. Results further support the use of RSM for media optimization. To the best of our knowledge, this is the first report of statistical media optimization for antibiotic production in rare actinomyceteNonomuraeaspecies, which will be useful for the development ofNonomuraeacultivation process for efficient antibiotic production on a large scale.

Bioproduction of Axenomycins in Batch Cultures of Streptomyces lisandri

1980 ◽  
Vol 35 (11-12) ◽  
pp. 936-944 ◽  
Author(s):  
H.-J. Bauch ◽  
E. Leistner
Keyword(s):  
Inorganic Phosphate ◽  
Antibiotic Production ◽  
Nitrogen Sources ◽  
Antibiotic Activity ◽  
Nutritional Requirements ◽  
Good Growth ◽  
Batch Cultures ◽  
Nutritional Components ◽  
Selection For

The influence of various factors such as aeration, pH and size of the inoculum on production of axenomycin A, B, and D and on growth of Streptomyces lisandri was studied in batch cultures. An investigation of the nutritional requirements showed that growth and antibiotic production are not necessarily correlated. The yield of acenomycins was increased to 1.7 g per liter medium by repeated selection for a high producing strain. Bioautography showed that these strains produced a hitherto undescribed antibiotic and that all strains tested differed in the total amount of axenomycins produced but not in the composition of the fraction containing antibiotic activity. Addition to the medium of extra amounts of inorganic phosphate and various nitrogen sources showed that both nutritional components selectively inhibited axenomycin formation but did not inhibit growth of Streptomyces lisandri. Good growth of Streptomyces lisandri was observed in the presence of sucrose and its monomers (glucose, fructose), but whereas sucrose inhibited axenomycin formation almost completely, its monomers did not.

scholarly journals Formulation and Statistical Optimization of Culture Medium for Improved Production of Antimicrobial Compound byStreptomycessp. JAJ06

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Polpass Arul Jose ◽  
Kunjukrishnan Kamalakshi Sivakala ◽  
Solomon Robinson David Jebakumar
Keyword(s):  
Antibiotic Production ◽  
Polynomial Equation ◽  
Optimization Method ◽  
Quadratic Model ◽  
Production Medium ◽  
Box Behnken Design ◽  
Enhanced Production ◽  
Burman Design ◽  
Plackett Burman Design ◽  
Salt Formulation

Streptomycessp. JAJ06 is a seawater-dependent antibiotic producer, previously isolated and characterised from an Indian coastal solar saltern. This paper reports replacement of seawater with a defined salt formulation in production medium and subsequent statistical media optimization to ensure consistent as well as improved antibiotic production byStreptomycessp. JAJ06. This strain was observed to be proficient to produce antibiotic compound with incorporation of chemically defined sodium-chloride-based salt formulation instead of seawater into the production medium. Plackett-Burman design experiment was applied, and three media constituents, starch, KBr, and CaCO3, were recognised to have significant effect on the antibiotic production ofStreptomycesJAJ06 at their individual levels. Subsequently, Response surface methodology with Box-Behnken design was employed to optimize these influencing medium constituents for the improved antibiotic production ofStreptomycessp. JAJ06. A total of 17 experiments were conducted towards the construction of a quadratic model and a second-order polynomial equation. Optimum levels of medium constituents were obtained by analysis of the model and numerical optimization method. When the strain JAJ06 was cultivated in the optimized medium, the antibiotic activity was increased to 173.3 U/mL, 26.8% increase as compared to the original (136.7 U/mL). This study found a useful way to cultivateStreptomycessp. JAJ06 for enhanced production of antibiotic compound.

scholarly journals Screening of Actinomycetes from Mangrove Ecosystem for L-asparaginase Activity and Optimization by Response Surface Methodology

2011 ◽  
Vol 60 (3) ◽  
pp. 213-221 ◽  
Author(s):  
RAJAMANICKAM USHA ◽  
KRISHNASWAMI KANJANA MALA ◽  
CHIDAMBARAM KULANDAISAMY VENIL ◽  
MUTHUSAMY PALANISWAMY
Keyword(s):  
Response Surface ◽  
Optimization Method ◽  
Mangrove Ecosystem ◽  
Optimum Level ◽  
Yeast Extract Medium ◽  
Asparaginase Activity ◽  
Burman Design ◽  
Plackett Burman Design ◽  
Central Composite ◽  
Design Experiments

Marine actinomycetes were isolated from sediment samples collected from Pitchavaram mangrove ecosystem situated along the southeast coast of India. Maximum actinomycete population was noted in rhizosphere region. About 38% of the isolates produced L-asparaginase. One potential strain KUA106 produced higher level of enzyme using tryptone glucose yeast extract medium. Based on the studied phenotypic characteristics, strain KUA106 was identified as Streptomyces parvulus KUA106. The optimization method that combines the Plackett-Burman design, a factorial design and the response surface method, which were used to optimize the medium for the production of L-asparaginase by Streptomycetes parvulus. Four medium factors were screened from eleven medium factors by Plackett-Burman design experiments and subsequent optimization process to find out the optimum values of the selected parameters using central composite design was performed. Asparagine, tryptone, d) extrose and NaCl components were found to be the best medium for the L-asparaginase production. The combined optimization method described here is the effective method for screening medium factors as well as determining their optimum level for the production of L-asparaginase by Streptomycetes parvulus KUAP106.

Evaluation of the growth and sporulation of different entomopathogenic fungi in different liquid and solid media at varied concentrations

2017 ◽  
Vol 6 (8) ◽  
pp. 5459
Author(s):  
Chandra Teja K. ◽  
Rahman S. J.
Keyword(s):  
Entomopathogenic Fungi ◽  
Large Scale ◽  
Insect Pests ◽  
Culture Media ◽  
Virulent Strain ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
Maximum Growth ◽  
Nutritional Requirements ◽  
Virulent Strains

Entomopathogenic fungi like Beauveria bassiana, Metarhizium anisopliae and Lecanicillium lecanii are used in biological control of agricultural insect pests. Their specific mode of action makes them an effective alternative to the chemical Insecticides. Virulent strains of Entomopathogenic fungi are effectively formulated and used as bio-insecticides world-wide. Amenable and economical multiplication of a virulent strain in a large scale is important for them to be useful in the field. Culture media plays a major role in the large-scale multiplication of virulent strains of Entomopathogens. Different substrates and media components are being used for this purpose. Yet, each strain differs in its nutritional requirements for the maximum growth and hence it is necessary to standardize the right components and their optimum concentrations in the culture media for a given strain of Entomopathogen. In the current study, three different nitrogen sources and two different carbon sources were tried to standardize the mass multiplication media for seven test isolates of Entomopathogenic fungi. A study was also conducted to determine the ideal grain media for the optimum conidial yields of the test isolates. Yeast extract was found to be the best Nitrogen source for the isolates. The isolates tested, differed in their nutritional requirements and showed variation in the best nitrogen and carbon sources necessary for their growth. Variation was also found in the optimum concentration of both the ingredients for the growth and sporulation of the isolates. In the solid-state fermentation study, rice was found to be the best grain for the growth of most of the fungi followed by barley. The significance of such a study in the development of an effective Myco-insecticide is vital and can be successfully employed in agriculture is discussed.

scholarly journals Polarization-Independent Circulator Based on Composite Rod of Ferrite and Plasma in Photonic Crystal Structure

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 381
Author(s):  
Mi Lin ◽  
Lixin Fu ◽  
Shakeel Ahmed ◽  
Qiong Wang ◽  
Yaoxian Zheng ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Large Scale ◽  
Optimization Method ◽  
Coupling Condition ◽  
High Isolation ◽  
Optimum Parameters ◽  
Composite Rod ◽  
Polarized Waves ◽  
Two Dimensional Photonic Crystal ◽  
Polarization Independent

We propose a type of polarization-independent circulator based on a composite rod of ferrite and plasma materials in a two-dimensional photonic crystal (PhC) slab. Only one composite rod was set at the center of the structure to provide circulation for both TE- and TM-polarized waves. Additionally, to improve the performance of the circulator, three additional rods were inserted to improve the coupling condition between the center magneto-optical microcavity and the corresponding waveguides. Finite element method was used to calculate the characteristics of the structure and the Nelder–Mead optimization method was employed to obtain the optimum parameters. The results show that a low insertion loss (~0.22 dB) and high isolation (~14 dB) can be achieved in our structure for waves of both TE and TM polarizations. The idea presented here may be useful for designing compact polarization devices in large-scale integrated photonic circuits.

An Adaptive Response Surface Method Using Bayesian Metric and Model Bias Correction Function

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
Lei Shi ◽  
Ren-Jye Yang ◽  
Ping Zhu
Keyword(s):  
Response Surface ◽  
Bias Correction ◽  
Adaptive Response ◽  
Large Scale ◽  
Correction Method ◽  
Data Uncertainty ◽  
Correction Function ◽  
Surface Model ◽  
Model Bias ◽  
Adaptive Response Surface Method

The Bayesian metric was used to select the best available response surface in the literature. One of the major drawbacks of this method is the lack of a rigorous method to quantify data uncertainty, which is required as an input. In addition, the accuracy of any response surface is inherently unpredictable. This paper employs the Gaussian process based model bias correction method to quantify the data uncertainty and subsequently improve the accuracy of a response surface model. An adaptive response surface updating algorithm is then proposed for a large-scale problem to select the best response surface. The proposed methodology is demonstrated by a mathematical example and then applied to a vehicle design problem.

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