Configurations of Culture Growth. A. L. Kroeber

1946 ◽  
Vol 18 (2) ◽  
pp. 163-165
Author(s):  
Max Savelle
Keyword(s):  
2019 ◽  
Vol 35 (6) ◽  
pp. 39-50
Author(s):  
T.V. Yuzbashev ◽  
A.S. Fedorov ◽  
F.V. Bondarenko ◽  
A.S. Savchenko ◽  
T.V. Vybornaya ◽  
...  

The present work describes an approach that improves the properties of the strain producing L-threonine via the reduction in the biomass accumulation during fermentation. Glutamyl- and glutaminyl-tRNA synthetases were chosen as targets. Mutants carrying temperature-sensitive alleles were obtained. It was shown that the used system caused the suppression of the function of tRNA synthetases which led to a rapid arrest of the culture growth, and an increase in productivity and yield of the L-threonine synthesis. One of the temperature-sensitive strains was used to obtain under non-permissive conditions of mutants with the suppressed above phenotype. Some of these mutants accumulate less biomass and produce by 10-12% more threonine than the original strain. Escherichia coli, producing strain, threonine, aminoacyl-tRNA synthetase, ts-mutation This work was supported by the Ministry of Science and Higher Education of the Russian Federation (project code RFMEFI61017X0011), and it was carried out using the equipment of the National Bio-Resource Center All-Russian Collection of Industrial Microorganisms, NRC «Kurchatov Institute» - GosNIIgenetika.


Author(s):  
Sundaram Mani ◽  
Sivakumar Mullaivanam Ramasamy ◽  
Saranya Chakrapani ◽  
Ambiganandam Krishna ◽  
Shyne Anand P.S ◽  
...  

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 533 ◽  
Author(s):  
Jiao-jiao Ji ◽  
Qi Feng ◽  
Hai-feng Sun ◽  
Xue-jun Zhang ◽  
Xiao-xiao Li ◽  
...  

Bioactive metabolites in Codonopsis pilosula are of particular interest as an immunostimulant. Methyl jasmonate (MeJA) plays an important role in the elicitation of metabolite biosynthesis. Here, we explored the response of metabolites to MeJA elicitation in C. pilosula adventitious roots and multiple shoots. The results showed that the biomass, polysaccharide, and lobetyolin content of adventitious roots exhibited the highest increases with 100 µmol·L−1 MeJA at the 16th day of subculture, whereas the atractylenolide III (a terpenoid) content increased extremely with 50 µmol·L−1 MeJA treatment at the 7th day of subculture. In addition, the biomass and lobetyolin content significantly increased at the 4th day after treatment. Similarly, the polysaccharide and lobetyolin content increased in multiple shoots. Further identification of different metabolites responding to MeJA by 1H-NMR showed an extremely significant increase of the lobetyolinin level, which coincided with lobetyolin. Accordingly, the precursor, fatty acids, showed a highly significant decrease in their levels. Furthermore, a significant increase in β-d-fructose-butanol glycoside was detected, which was accompanied by a decrease in the sucrose level. Accordingly, the enzyme genes responsible for terpenoid and carbohydrate biosynthesis, CpUGPase, and CpPMK, were up regulated. In conclusion, MeJA promoted culture growth and accelerated bioactive metabolite accumulation by regulating the expression of the metabolite biosynthesis related genes, CpUGPase and CpPMK in C. pilosula.


2008 ◽  
Vol 58 (5) ◽  
pp. 1101-1106
Author(s):  
Pichiah Saravanan ◽  
K. Pakshirajan ◽  
P. K. Saha

An indigenous mixed culture of microorganisms, isolated from a sewage treatment plant, was investigated for its potential to simultaneously degrade phenol and m-cresol during its growth in batch shake flasks. 22 full factorial designs with the two substrates as the factors, at two different levels and two different initial concentration ranges, were employed to carry out the biodegradation experiments. For complete utilisation of phenol and m-cresol, the culture took a minimum duration of 21 hrs at their low concentration of 100 mg/L each, and a maximum duration of 187 hrs at high concentration of 600 mg/L each in the multisubstrate system. The biodegradation results also showed that the presence of phenol in low concentration range (100–300 mg/L did not inhibit m-cresol biodegradation; on the other hand, presence of m-cresol inhibited phenol biodegradation by the culture. Moreover, irrespective of the concentrations used, phenol was degraded preferentially and earlier than m-cresol. During the culture growth, a lag phase was observed above a combined concentration of 500 mg/L i.e., 200 mg/L m-cresol and 300 mg/L of phenol and above). Statistical analysis of the specific growth rate of the culture in the multisubstrate system was also performed in the form of ANOVA and Student ‘t’ test, which gave good interpretation in terms of main and interaction effects of the substrates.


1989 ◽  
Vol 68 (2) ◽  
pp. 123-130 ◽  
Author(s):  
Ayaaki Ishizaki ◽  
Tomomi Ohta ◽  
Genta Kobayashi

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