scholarly journals Melanin synthesis by black yeast-like fungi Psedonadsoniella brunnea: dependence of L-tyrosine quantity in the cultural medium

2019 ◽  
Vol 26 (1) ◽  
pp. 41-46 ◽  
Author(s):  
T. Kondratiuk ◽  
T. Beregova ◽  
T. Akulenko ◽  
Ie. Torgalo ◽  
V. Vereschaka
Keyword(s):  
Nutrient Medium ◽  
Culture Medium ◽  
Statistical Processing ◽  
Black Yeast ◽  
Malt Extract ◽  
Melanin Synthesis ◽  
Optimal Conditions ◽  
Cultural Medium ◽  
Yeast Fungi ◽  
Series Of Experiments

To determine the optimal conditions for the synthesis of melanin by black yeast fungi Pseudonadsoniella brunnea (Basidiomycota, Agaricomycotina, Agaricomycetes, Polyporales, Meripilaceae), depending on the amount of L-tyrosine in the culture medium was the purpose of the work. The standard Malt Extract Broth (MEB) liquid nutrient medium was used within this study. L-tyrosine was added to the culture medium in a quantity of 0.01, 0.025 and 0.05%.To obtain the melanin the cultivation of Pseudonadsoniella brunnea was carried out at pH 1-1.5, temperature + 21 ± 1 ° C during 7 days. Statistical processing of the results was carried out using generally accepted methods of variation statistics. It has been established that the level of melanin synthesis by black yeast-like fungi Pseudonadsoniella brunnea depends on the amount of L-tyrosine introduced into the culture medium. The MEB nutrient medium containing 0.05% L-tyrosine in this series of experiments found to be the best composition for obtaining melanin by the strain-producer Pseudonadsoniella brunnea. Compared to control (MEB without L-tyrosine), the amount of melanin synthesized by Ps. brunnea in these conditions increased by 2.5 times. The further research into the optimal conditions for the cultivation of black yeast-like fungi Pseudonadsoniella brunnea in order to obtain melanin is relevant and promising.

scholarly journals In vitro plant regeneration of Christmas cactus (Schlumbergera truncata (Haw.) Moran) by indirect morphogenesis

2021 ◽  
Vol 63 (1) ◽  
pp. 68-73
Author(s):  
Oksana Chornobrov ◽  
Svitlana Bilous
Keyword(s):  
Nutrient Medium ◽  
Culture Medium ◽  
Callus Formation ◽  
Shoot Proliferation ◽  
Root Induction ◽  
Optimal Conditions ◽  
In Vitro Plant Regeneration ◽  
Yellow Pigmentation ◽  
Dark Green

Abstract Plants of Schlumbergera truncata (Haw.) Moran were obtained by indirect morphogenesis from the segment section of shoots in vitro, they were multiplied and rooted. Also were determined the effect of the lighting regime, the composition of the nutrient medium on the consistency and frequency of callus formation. The studies were conducted during 2016–2018. The mode of effective sterilization (more than 90%) of S. truncata plant explants using 0.1% HgCl2 for 7–8 min was established. Optimal conditions for the induction of callus formation in stem node segments of S. truncata plants (rate more than 90% and significant growth) were created on MS (Murashige and Skoog 1962) nutrient medium supplemented with 1.0 mg/l BAP (6-benzylaminopurine) and 0.3 mg/l NAA (1-naphthylacetic acid) under conditions of placement on the nutrient medium and doing a significant number of cuts on the explants. The light intensity of 2.0–3.0 klx, obtained by a callus of dense consistency of dark green pigmentation, when using the thermostat condition without illumination, the callus had loose consistency, dark yellow pigmentation. It is established that the influence of the lighting regime and the composition of the nutrient medium on the frequency of callus formation is statistically significant. The largest number of shoots was obtained on the MS medium with the addition of 2.0 mg/l of BA. At the same times, shoot proliferation and root induction in such numbers were observed on MS culture medium with the addition of 0.5 mg/l BA and 0.5 mg/l kinetin (multiplication factor – 8.8±0.6 per 60-day cultivation cycle).

Development of embryonic rat eyes in organ culture

Development ◽  
1968 ◽  
Vol 19 (3) ◽  
pp. 407-414
Author(s):  
R. Christy Armstrong ◽  
Joel J. Elias
Keyword(s):  
Organ Culture ◽  
Culture Medium ◽  
Folic Acid Deficiency ◽  
Experimental Conditions ◽  
Acid Deficiency ◽  
Series Of Experiments ◽  
Development In Vitro ◽  
Ocular System

Abnormalities of the ocular system which appear in organ culture in Waymouth's medium with freshly added glutamine (Armstrong & Elias, 1968) resemble those caused by transitory pteryolglutamic acid (PGA or folic acid) deficiency in vivo (Armstrong & Monie, 1966). The configurations of such malformations as lens herniations, retinal diverticula, and rosette-like formations of the retina are remarkably similar in both cases. The experiments reported in this paper were undertaken in an effort to understand the mechanisms involved in the production of similar abnormalities by two very different experimental conditions: the addition of glutamine in vitro and the transitory deficiency of PGA in vivo. One series of experiments involved the effects of manipulation of the PGA and glutamine content of the culture medium on eye development in vitro. Parallel studies on PGA-deficiency in vivo were undertaken in conjunction with organ-culture experiments in order to compare the effects on abnormal eye morphogenesis.

Eco-Friendly Dye-free Coloration Technology for Wool Based on Fenton Reagent Pretreatment

2011 ◽  
Vol 239-242 ◽  
pp. 3327-3330 ◽  
Author(s):  
Yan Ling Sui ◽  
Yong Zhu Cui
Keyword(s):  
Nitric Acid ◽  
Emission Reduction ◽  
Optimal Conditions ◽  
Fenton Reagent ◽  
Saving Energy ◽  
Before And After ◽  
Series Of Experiments

The wool was pretreated with Fenton reagent in this paper, on this basis, 4-hydroxy benzaldehyde and concentrated nitric acid were used to discuss the dye-free coloration deeply. It was analyzed comparatively through a series of experiments on the wool before and after Fenton reagent pretreatment, and the effects of concentrations, temperature and time on the coloration were further discussed. The experiment indicated that, compared with untreated wool, the color of wool with Fenton reagent pretreatment was deeper and the coloration rate was quicker. It realized good coloration at lower temperatures, which achieved the goal of saving energy and emission reduction. The optimal conditions were that concentrations of 4-hydroxy benzaldehyde and concentrated nitric acid were 2.5% and 3% respectively, reacting time was 90min, and reacting temperature was 70°C.

scholarly journals Effect of culture medium light and air circulation on sporulation of Neonectria ditissima

2014 ◽  
Vol 67 ◽  
pp. 123-132 ◽  
Author(s):  
R.W.A. Scheper ◽  
B.M. Fisher ◽  
N.T. Amponsah ◽  
M. Walter
Keyword(s):  
Culture Media ◽  
Ultra Violet ◽  
Fluorescent Light ◽  
Malt Extract ◽  
Causal Organism ◽  
Light Regimes ◽  
Large Numbers ◽  
Light Darkness ◽  
Series Of Experiments ◽  
Air Circulation

In culture most isolates of Neonectria ditissima the causal organism of European canker do not produce conidia Those that do often produce singlecelled conidia rather than the typical multicelled conidia that are found in nature A series of experiments was conducted to determine the conditions needed for conidium production Four culture media (malt extract agar modified Matsushimas medium (MM) apple sap amended water agar (ASAWA) and water agar) five light regimes including darkness near ultra violet (NUV) light and white fluorescent light and three plate sealing patterns were tested Subculturing isolates producing large numbers of viable conidia of which 71 produced multicelled conidia Similarly under a white fluorescent light/darkness regime all isolates produced viable conidia on MM and ASAWA and 100 and 97 of the isolates produced multicelled conidia respectively

scholarly journals APPLICATION OF MATHEMATICAL PLANNING OF THE EXPERIMENT IN THE CHOOSING THE OPTIMUM CONDITIONS OF THE VAPOR-PHASE GAS-CHROMATOGRAPHIC DETERMINATION OF FORMALDEHYDE IN THE URINE

2018 ◽  
Vol 97 (10) ◽  
pp. 985-989 ◽  
Author(s):  
Аnton N. Alekseenko ◽  
O. M. Zhurba
Keyword(s):  
Mathematical Model ◽  
Vapor Phase ◽  
Statistical Processing ◽  
Analytical Signal ◽  
Heating Time ◽  
Gas Extraction ◽  
Optimal Conditions ◽  
Steep Ascent ◽  
The Mathematical Model

Introduction. There was substantiated a method for the determination of formaldehyde by vapor-phase gas chromatography by the use of derivatizing reagent o-(2,3,4,5,6-pentafluorbenzyl)hydroxylamine. Material and methods. Formaldehyde in urine was derivatized to o-pentafluorobenzyloxime and recovered to the vapor phase by heating the urine sample with o-(2,3,4,5,6-pentafluorbenzyl)hydroxylamine in a sealed vial. Gas-chromatographic analysis of the vapor-air phase was performed in a mode of the temperature gradient on a capillary column HP-5 with a flame ionization detector. Identification of the analyte in the form of the derivative-o- pentafluorobenzyloxime of formaldehyde was carried out according to the absolute retention time, which was established by comparing the chromatograms of model formaldehyde mixtures in the urine of different concentrations. Results. The optimal conditions for gas extraction are selected using mathematical experimental planning. The most important factors of gas extraction in the vapor-phase analysis are the temperature and time of the establishment of the interphase equilibrium with heating. From the experimentally obtained curves of the analytical signal on the temperature and the heating time, the zero level and the interval of variation of these factors are chosen. A matrix for planning a 2-factor experiment was constructed. The coefficients of the mathematical model are determined. There was carried out statistical processing of the experimental data, which was reduced to the estimation of the reproducibility of the optimization parameter and to the evaluation of the significance of the coefficient of the mathematical model. The adequacy of the mathematical model was evaluated, its interpretation was carried out. Discussion. The peak area of the analyte increases with the elevating the temperature and heating time, due to an increase in the analyte concentration in the vapor phase. Moreover, the heating time makes a greater contribution to the formation of the analytical signal than the temperature. The step of motion along the gradient was calculated and the experiments of steep ascent were carried out. Conclusion. According to the results of the steep ascent experiments, the optimal conditions for the gas extraction of formaldehyde in the form of a derivative were chosen.

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.

scholarly journals Unravelling the Role of Melanin in Cd and Zn Tolerance and Accumulation of Three Dark Septate Endophytic Species

2020 ◽  
Vol 8 (4) ◽  
pp. 537
Author(s):  
Charlotte Berthelot ◽  
Asfaw Zegeye ◽  
Dalia A. Gaber ◽  
Michel Chalot ◽  
Philipp Franken ◽  
...  
Keyword(s):  
Trace Element ◽  
Cell Walls ◽  
Functional Trait ◽  
Dark Septate Endophytes ◽  
Melanin Synthesis ◽  
Melanin Production ◽  
Cd Accumulation ◽  
Series Of Experiments ◽  
Zn Tolerance

Dark septate endophytes (DSEs) are often trace element (TE)-tolerant fungi and are abundant in TE-polluted environments. The production of melanin, a black polymer found in cell walls, was hypothesized by several authors to play a role in the TE tolerance of DSEs. To test this hypothesis, we established a series of experiments using albino strains and melanin inhibitors and examined the responses to Cd and Zn. Six DSEs belonging to genera Cadophora sp., Leptodontidium sp. and Phialophora mustea, were evaluated. The strains mainly produced 1,8-dihydroxynaphthalene (DHN) melanin whereas 3,4-dihydroxyphenylalanin melanin was also synthetized. Cd and Zn decreased melanin synthesis in most of the strains. A reduction in melanin concentration in hyphae through the use of tricyclazole, an inhibitor of DHN-melanin synthesis, did not reduce the tolerance of the strains to Cd and Zn. Similarly, albino mutants of Leptodontidium sp. were not more sensitive to Cd and Zn than the WT strain. Moreover, tricyclazole-treated colonies accumulated less Cd but more Zn compared to untreated colonies. The Cd and Zn contents of Leptodontidium albino strains were variable and similar to that of the WT. The results suggest that melanin production is not an important functional trait that contributes to Cd and Zn tolerance, but might contribute to Cd accumulation.

INSULIN RELEASE FROM HUMAN FOETAL PANCREAS IN TISSUE CULTURE

1973 ◽  
Vol 59 (1) ◽  
pp. 65-79 ◽  
Author(s):  
F. N. LEACH ◽  
M. A. ASHWORTH ◽  
A. J. BARSON ◽  
R. D. G. MILNER
Keyword(s):  
Tissue Culture ◽  
Insulin Release ◽  
Culture Medium ◽  
Calf Serum ◽  
Insulin Degradation ◽  
Optimal Conditions ◽  
Plasma Clot ◽  
Collagenase Digestion ◽  
Incubation Experiments ◽  
Foetal Pancreas

SUMMARY Various methods of tissue culture were studied in an attempt to grow human foetal pancreas under conditions favourable for insulin release. Simple dicing of pancreas was superior to plasma clot adhesion or collagenase digestion for the preparation of tissue for culture. The culture medium described by Kahri (1966) (containing 25% heated postnatal calf serum) was the most suitable of four tested for the study of insulin release from the tissue culture. In this medium insulin could be measured quantitatively by radioimmunoassay and insulin degradation occurred at the rate of 20–25%/24 h. In other media the pancreas grew less well or insulin degradation was much greater. Human foetal pancreas grown under optimal conditions released insulin for up to 34 days. Insulin released into the culture medium did not appear to inhibit the further release of insulin. In some experiments the total amount of insulin released into the culture medium was several-fold greater than that in the pancreas originally seeded. In acute incubation experiments barium and theophylline stimulated insulin release from pancreas cultures. It proved impossible to identify the cells from which insulin was released but they did not appear to be in the monolayer which was composed of fibroblasts.

scholarly journals A METHOD FOR THE PHYSIOLOGICAL STUDY OF TISSUES IN VITRO

1923 ◽  
Vol 38 (4) ◽  
pp. 407-418 ◽  
Author(s):  
Alexis Carrel
Keyword(s):  
Nutrient Medium ◽  
Bacterial Contamination ◽  
Culture Medium ◽  
Residual Activity ◽  
Physical Factors ◽  
Dynamic Changes ◽  
Fluid Medium ◽  
Continuous Growth ◽  
Pure Cultures

1. A method has been developed which allows the continuous growth of pure strains of fibroblasts, epithelium, and leucocytes in a medium which undergoes but slight spontaneous deterioration. 2. The principle of the method is to leave the tissues undisturbed while the medium is changed. This was realized by special containers allowing the change of the medium without bacterial contamination and by the simultaneous use of a solid and a fluid medium. 3. The curve of growth of pure cultures of fibroblasts and epithelial cells in a nutrient medium is a parabola; in a non-nutrient medium, it is S-shaped and expresses the residual activity of the tissues. Leucocytes invade the culture medium progressively, as do bacteria, but never aggregate in a tissue. 4. The method is used for the study of the morphological and dynamic changes occurring in tissues under the influence of chemical and physical factors.

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