scholarly journals Optimisation of Synthetic Medium Composition for Levorin Biosynthesis by Streptomyces levoris 99/23 and Investigation of its Accumulation Dynamics Using Mathematical Modelling Methods

2010 ◽  
Vol 59 (3) ◽  
pp. 179-183
Author(s):  
VESELIN S. STANCHEV ◽  
LUBKA Y. KOZHUHAROVA ◽  
BORIANA Y. ZHEKOVA ◽  
VELIZAR K. GOCHEV
Keyword(s):  
Mathematical Modelling ◽  
Culture Medium ◽  
Synthetic Medium ◽  
Equation System ◽  
Medium Composition ◽  
Antibiotic Biosynthesis ◽  
Medium Components ◽  
Linear Differential ◽  
Modelling Methods ◽  
Streptomyces Levoris

The composition of a synthetic culture medium for levorin biosynthesis by Streptomyces levoris 99/23 was optimised using mathematical modelling methods. The optimal concentrations of the medium components were established by means of an optimum composition design at three factor variation levels. An adequate regression model was obtained. Levorin biosynthesis by Streptomyces levoris 99/23 in the optimised synthetic medium was over 38% higher than in the initial medium. The antibiotic biosynthesis dynamics in the optimised culture medium was studied by means of a non-linear differential equation system. The resultant model was valid.

scholarly journals Influence of the Medium Composition and the Culture Conditions on Surfactin Biosynthesis by a Native Bacillus subtilis natto BS19 Strain

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2985
Author(s):  
Beata Koim-Puchowska ◽  
Grzegorz Kłosowski ◽  
Joanna Maria Dróżdż-Afelt ◽  
Dawid Mikulski ◽  
Alicja Zielińska
Keyword(s):  
Surface Tension ◽  
Bacillus Subtilis ◽  
Culture Medium ◽  
Synthetic Medium ◽  
Culture Conditions ◽  
Medium Composition ◽  
Native Strain ◽  
Medium Components ◽  
Bacillus Subtilis Natto ◽  
The Impact

An effective microbial synthesis of surfactin depends on the composition of the culture medium, the culture conditions and the genetic potential of the producer strain. The aim of this study was to evaluate the suitability of various medium components for the surfactin producing strain and to determine the impact of the culture conditions on the biosynthesis of surfactin isoforms by the newly isolated native strain Bacillus subtilis natto BS19. The efficiency of surfactin biosynthesis was determined by measuring the surface tension of the medium before and after submerged culture (SmF) and by qualitative and quantitative analysis of the obtained compound by high performance liquid chromatography. The highest efficiency of surfactin biosynthesis was achieved using starch as the carbon source and yeast extract as the nitrogen source at pH 7.0 and 37 °C. Potato peelings were selected as an effective waste substrate. It was shown that the increase in the percentage of peel extract in the culture medium enhanced the biosynthesis of surfactin (mg/L) (2–30.9%; 4–46.0% and 6–58.2%), while reducing surface tension of the medium by about 50%. The obtained results constitute a promising basis for further research on biosynthesis of surfactin using potato peelings as a cheap alternative to synthetic medium components.

Pertumbuhan Dan Perkembangan Anggrek Dendrobium anosmum Pada Media Kultur In Vitro Dengan Beberapa Konsentrasi Air Kelapa

Agrologia ◽  
2018 ◽  
Vol 1 (1) ◽  
Author(s):  
S. Tuhuteru ◽  
Meity L Hehanussa ◽  
Simon H.T Raharjo
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Water Concentration ◽  
Medium Composition ◽  
Coconut Water ◽  
Orchid Species ◽  
Randomized Design ◽  
Wet Weight ◽  
Completely Randomized Design

Dendrobium anosmum is one of natural orchids in Indonesia. Optimization of medium composition for orchid propagation through in vitro culture is necessary to enhance propagule multiplication capabilities and quality. This study was aimed to study the influence of concentration of coconut water in culture medium on in vitro growth and development of D. anosmum orchid species and to determine the optimal coconut water concentration in culture media.  The experiment were arranged in a Completely Randomized Design with four treatments and eight replications. The treatments consisted of the addition of coconut water with concentrations: 0 ml•l -1 (control), 50 ml•l-1, 100 ml•l-1 and 150 ml•l-1. The results showed that addition of coconut water in culture medium gave different effect on shoot growth and multiplication of D. anosmum orchids.  Coconut water concentration of 100 ml•l-1 was the best concentration for growth and multiplication of D. anosmum orchids, based on both shoots and roots growth, plantlet height and wet weight.

Differentiation of mesenchymal stem cells from humans and animals into insulin-producing cells: An overview in vitro induction forms

2020 ◽  
Vol 16 ◽  
Author(s):  
Bruna O. S. Câmara ◽  
Bruno M. Bertassoli ◽  
Natália M. Ocarino ◽  
Rogéria Serakides
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Culture Medium ◽  
Adipogenic Differentiation ◽  
Medium Composition ◽  
Cell Therapies ◽  
Insulin Producing Cells ◽  
Msc Differentiation

The use of stem cells in cell therapies has shown promising results in the treatment of several diseases, including diabetes mellitus, in both humans and animals. Mesenchymal stem cells (MSCs) can be isolated from various locations, including bone marrow, adipose tissues, synovia, muscles, dental pulp, umbilical cords, and the placenta. In vitro, by manipulating the composition of the culture medium or transfection, MSCs can differentiate into several cell lineages, including insulin-producing cells (IPCs). Unlike osteogenic, chondrogenic, and adipogenic differentiation, for which the culture medium and time are similar between studies, studies involving the induction of MSC differentiation in IPCs differ greatly. This divergence is usually evident in relation to the differentiation technique used, the composition of the culture medium, the cultivation time, which can vary from a few hours to several months, and the number of steps to complete differentiation. However, although there is no “gold standard” differentiation medium composition, most prominent studies mention the use of nicotinamide, exedin-4, ß-mercaptoethanol, fibroblast growth factor b (FGFb), and glucose in the culture medium to promote the differentiation of MSCs into IPCs. Therefore, the purpose of this review is to investigate the stages of MSC differentiation into IPCs both in vivo and in vitro, as well as address differentiation techniques and molecular actions and mechanisms by which some substances, such as nicotinamide, exedin-4, ßmercaptoethanol, FGFb, and glucose, participate in the differentiation process.

scholarly journals STUDIES ON THE ANTIBACTERIAL ACTION OF THE SULFONAMIDE DRUGS

1942 ◽  
Vol 75 (4) ◽  
pp. 383-394 ◽  
Author(s):  
W. Barry Wood ◽  
Robert Austrian
Keyword(s):  
Bacterial Growth ◽  
Culture Medium ◽  
Organic Dyes ◽  
Synthetic Medium ◽  
Antibacterial Properties ◽  
Antagonistic Action ◽  
Bacteriostatic Action ◽  
Great Excess ◽  
Related Drug

1. In cultures of Staphylococus aureus in a synthetic medium nicotinamide and cozymase were shown to block the bacteriostatic action of chemically unrelated sulfonamide drugs as well as the chemically related compound sulfapyridine. The antibacterial properties of organic dyes totally unrelated to the sulfonamide compounds (methylene blue and thionine) were also nullified by the addition of cozymase to the culture medium. 2. The antagonistic action of the pyridine-containing coenzyme, cozymase, was found, by quantitative study, to be no greater against sulfapyridine than against other structurally dissimilar sulfonamide compounds. 3. The antidrug effects of nicotinamide and cozymase in staphylococcus cultures were observed to be directly proportional to their ability to stimulate the growth of the organism in the synthetic medium. When tested in cultures of B. coli in which they failed to accelerate bacterial growth, these same substances failed to influence the bacteriostatic action of the sulfonamide drugs. 4. The in vitro action of the coenzyme, cocarboxylase, as measured in the Warburg respirometer, was shown to be unaffected by the chemically related drug, sulfathiazole, even when the latter was present in great excess. The above observations fail to support the theory that sulfapyridine, sulfathiazole, and sulfadiazine prevent bacterial growth by interfering with the functioning of the chemically related coenzymes, cozymase, and cocarboxylase. The mode of action of sulfanilamide and its more common derivatives is discussed in the light of these observations, and a tentative theory is offered to explain the differences in bacteriostatic potency exhibited by the various sulfonamide compounds.

scholarly journals Efficiency of using different types induction culture medium for hexaploid triticale anther cultivation

2019 ◽  
Vol 25 ◽  
pp. 260-265
Author(s):  
E. V. Lagunovskaya ◽  
O. I. Zaitseva ◽  
V. A. Lemesh
Keyword(s):  
Culture Medium ◽  
Medium Composition ◽  
Induction Medium ◽  
Hexaploid Triticale ◽  
Culture Methods ◽  
Study Results ◽  
Short Period ◽  
Androgenesis In Vitro ◽  
The Republic

Aim. Triticale is one of the main grain crops of the Republic of Belarus. Further progress in the selection of this culture involves the accelerated creation of highly productive early ripening varieties resistant to abiotic and biotic factors. The method of induced androgenesis in vitro makes it possible to obtain stable homozygous lines in a short period of time and to eliminate the lengthy process of inbreeding used in classical breeding to fix the desired traits. Methods. The tissue and cell culture methods for plants was used in the study. Results. The influence of the induction medium composition on the efficiency of in vitro induced androgenesis in varieties and lines of hexaploid triticale is assessed. The influence of three types of induction culture medium, the type of phytohormones and the presence or absence of cefotaxime in the medium are analyzed. Results. It has been shown that using the C-17 culture medium supplemented with 2.0 mg/l 2,4-D and 0.5 mg/l kinetin without adding cefotaxime is most effective for the anther triticale cultivation. Keywords: triticale, anther culture, induction nutrient medium, embryoids, calli, regenerant plants, cefotaxime.

scholarly journals Mathematical Modelling of Deforestation Due to Population Density and Industrialization

Jurnal Varian ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 9-16
Author(s):  
Didiharyono D. ◽  
Irwan Kasse
Keyword(s):  
Numerical Simulation ◽  
Population Density ◽  
Mathematical Modelling ◽  
Equilibrium Point ◽  
Equilibrium Points ◽  
Stability Criteria ◽  
Hurwitz Stability ◽  
Stable Conditions ◽  
Linear Differential ◽  
The Stability

The focus of the study in this paper is to model deforestation due to population density and industrialization. To begin with, it is formulated into a mathematical modelling which is a system of non-linear differential equations. Then, analyze the stability of the system based on the Routh-Hurwitz stability criteria. Furthermore, a numerical simulation is performed to determine the shift of a system. The results of the analysis to shown that there are seven non-negative equilibrium points, which in general consist equilibrium point of disturbance-free and equilibrium points of disturbances. Equilibrium point TE7(x, y, z) analyzed to shown asymptotically stable conditions based on the Routh-Hurwitz stability criteria. The numerical simulation results show that if the stability conditions of a system have been met, the system movement always occurs around the equilibrium point.

Mathematical Modelling the Power Supply-Load System for Electro-Discharge Polishing Process

2010 ◽  
Vol 159 ◽  
pp. 125-128
Author(s):  
A. Parshuta ◽  
V. Chitanov ◽  
Lilyana Kolaklieva ◽  
Roumen Kakanakov
Keyword(s):  
Mathematical Model ◽  
Mathematical Modelling ◽  
Numerical Solution ◽  
Power Supply ◽  
Equation System ◽  
Electrolyte Temperature ◽  
Polishing Process ◽  
The Real ◽  
Quadratic Interpolation ◽  
Runge Kutta

The real electro-discharge polishing (EDP) system has been presented by an equivalent electrical scheme and described by a corresponded equation system. The Runge-Kutta-Merson method with automatically changed step is used for the numerical solution the equation system. The current through the resistor equivalent to the steam gas wrapper is defined with an I-V characteristic obtained by the method of multi-interval quadratic interpolation-approximation. A mathematical model of the power supply-load system has been realized in Basic and Matlab® languages. On the base of the developed modelling conditions limiting the current and voltage overload in the EDP system have been determined depending on the maximum polished area and the electrolyte temperature.

scholarly journals Theoretical Vibration Analysis Regarding Excitation due to Elliptical Shaft Journals in Sleeve Bearings of Electrical Motors

2012 ◽  
Vol 2012 ◽  
pp. 1-19 ◽  
Author(s):  
Ulrich Werner
Keyword(s):  
Differential Equation ◽  
Mathematical Description ◽  
Vibration Analysis ◽  
Equation System ◽  
Electrical Machines ◽  
Differential Equation System ◽  
Kinematic Constraints ◽  
Linear Differential ◽  
Electrical Motors ◽  
Rotor Mass

This paper shows a theoretical vibration analysis regarding excitation due to elliptical shaft journals in sleeve bearings of electrical motors, based on a simplified rotordynamic model. It is shown that elliptical shaft journals lead to kinematic constraints regarding the movement of the shaft journals on the oil film of the sleeve bearings and therefore to an excitation of the rotordynamic system. The solution of the linear differential equation system leads to the mathematical description of the movement of the rotor mass, the shaft journals, and the sleeve bearing housings. Additionally the relative movements between the shaft journals and the bearing housings are deduced, as well as the bearing housing vibration velocities. The presented simplified rotordynamic model can also be applied to rotating machines, other than electrical machines. In this case, only the electromagnetic spring valuecmhas to be put to zero.

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