Selection of new highly active L-alanine producer strains of Brevibacterium flavum and comparison of their activity in alanine synthesis

The biologically active aldehydes in extracts of fungi of the genus Lactarius were identified. It’s established that these substances are unstable, they are found in fresh and frozen fungi, but are absent in dried mushrooms and interact with 1,4-phenylenediamine to form a colored compound. Methylene chloride is the best extragent for these substances. TLC on silufol plates showed that there were several substances in Lactarius pergamenus fruiting bodies and they had varying degrees of stability. For selection of these substances, methylene chloride extract was separated on a column of silica gel. Fraction, which gave the most expressive reaction with 1,4-phenylenediamine on thin-layer chromatograms were analyzed by GC-MS both in the absence and in the presence of 1,4-phenylenediamine. As a result, it was found that 1,4-phenylenediamine or other aromatic amines interacted with highly active aldehydes, that were present in fruiting bodies. Among them 2,2-dimethylocta- 3,4-dienal was the most stable and was present in the biggest quantity. This substance very rarely occurs in the vegetable kingdom and in fungi extracts of Lactarius genus wasn’t previously described. Its possible function in fungi is prevention of damage by parasites and eating by animals.

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РАЗРАБОТКА ВЫСОКОАКТИВНОГО ШТАММА-ПРОДУЦЕНТА ВИРДЖИНИАМИЦИНА И ПОВЫШЕНИЕ ЕГО ПРОДУКТИВНОСТИ С ПОМОЩЬЮ СИНТЕТИЧЕСКИХ АБСОРБИРУЮЩИХ СМОЛ

Biological Bulletin of Bogdan Chmelnitskiy Melitopol State Pedagogical University ◽

10.15421/201687 ◽

2016 ◽

Vol 6 (3) ◽

pp. 195-208 ◽

Cited By ~ 1

Author(s):

V. A. Savushkin ◽

V. V. Dzhavakhiya ◽

E. V. Glagoleva ◽

V. V. Savel'eva ◽

E. D. Popova ◽

...

Keyword(s):

Fermentation Medium ◽

Culture Broth ◽

Medium Composition ◽

Basic Medium ◽

High Productivity ◽

Highly Active ◽

Different Types ◽

Total Productivity ◽

Industrial Use ◽

Selection Of

Virginiamycin, an antibiotic produced by some Streptomyces species, is widely used in veterinary and bioethanol production. It represents a natural mix of two different macrocyclic components, among which M1 and S1 factors are the main acting components. M1 and S1 act synergistically when present in the optimum ratio of 60-75% of M1 and 25-40% of S1. Due to a large number of genes involved into the virginiamycin biosynthesis, the development of overproducing strains able to synthesize M1 and S1 at a synergistic ratio with the total productivity exceeding 3-4 g/L still remains a relevant problem. Using a multi-step random UV mutagenesis of the Streptomyces sp. strain DSM40559, a highly active strain S 15-30 was obtained, which virginiamycin titer on a basic medium significantly increased that of the parental strain (2.6 and 0.35 g/L, respectively), and the M1:S1 ratio remained synergistic (72:28). Various sources of carbon, nitrogen, and macroelements were evaluated for medium improvement, and several different types of synthetic macroporous resins were tested to provide the highest virginiamycin titer in culture broth of the developed strain. The resulting improved fermentation medium supplemented with 20 g/L of Amberlite XAD-16 resin increased strain productivity up to 5.03 ± 0.12 g/L with the simultaneous maintenance of the M1:S1 ratio within the synergistic range (72:28) and highly selective level of adsorption of the antibiotic from culture broth (92-95%). The variability of the M1:S1 ratio in the total antibiotic titer depending on various medium composition and resin type was first demonstrated. The obtained strain is promising for the industrial use due to its high productivity and the optimal M1:S1 ratio. Results of the study will be used for the further selection of overproducing strains and the scaling up of the virginiamycin production. The obtained data can be interesting for other researchers working in the field of production of macrolide antibiotics.

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Effective polymer concrete on waste concrete production

E3S Web of Conferences ◽

10.1051/e3sconf/20199702032 ◽

2019 ◽

Vol 97 ◽

pp. 02032

Author(s):

Evgeny Pyataev ◽

Alexey Zhukov ◽

Kirill Vako ◽

Marina Burtseva ◽

Elizaveta Mednikova ◽

...

Keyword(s):

Average Density ◽

Polymer Concrete ◽

Polymer Additive ◽

Highly Active ◽

Active Experiment ◽

High Durability ◽

Concrete Production ◽

Building Systems ◽

Active Waste ◽

Selection Of

Finish materials in facade systems are experiencing significant stress associated with atmospheric and mechanical influences. The use of tiles with high durability and the ability to relax deformations will allow to obtain efficient cladding for building systems. The article presents the results of the selection of compositions and technologies of a composite material based on finely ground highly active waste produced by portland cement, mineral binder, additives based on polycarboxylic ether MC-6955, and polymer additive MC-Adhesive. MC-Adhesive is a polymer additive used for: a significant increase in flexural strength; reduce the elastic modulus; increase water resistance; increase the concrete mix cohesion; making coatings with high requirements for abrasion, low dusting and high resistance to aggressive substances.The article presents the results of research methods of selection of compositions of composite polymer concrete. The strength characteristics of polymer concrete with an average density of 2370-2450 kg/m3 are most dependent on the consumption of fine waste and polymer additives. The nomogram obtained as a result of an active experiment makes it possible to evaluate the dependence of the strength on these factors and select their optimal ratio.

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Selection of psychrotrophic Leuconostoc spp. producing highly active dextransucrase from lactate fermented vegetables

International Journal of Food Microbiology ◽

10.1016/j.ijfoodmicro.2007.02.027 ◽

2007 ◽

Vol 117 (1) ◽

pp. 61-67 ◽

Cited By ~ 58

Author(s):

Hyun-Ju Eom ◽

Dong Mi Seo ◽

Nam Soo Han

Keyword(s):

Highly Active ◽

Fermented Vegetables ◽

Selection Of

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Lanthanide-dependent RNA-cleaving DNAzymes as metal biosensors

Canadian Journal of Chemistry ◽

10.1139/cjc-2014-0465 ◽

2015 ◽

Vol 93 (3) ◽

pp. 273-278 ◽

Cited By ~ 14

Author(s):

Juewen Liu

Keyword(s):

Sensor Array ◽

Activity Patterns ◽

Chemical Properties ◽

Toxic Heavy Metals ◽

Future Directions ◽

Highly Active ◽

Lanthanide Series ◽

Rational Ligand Design ◽

Heavy Lanthanides ◽

Selection Of

Lanthanides represent a group of very important but challenging analytes for biosensor development. These 15 elements are very similar in their chemical properties. So far, limited success has been realized using the rational ligand design approach. My laboratory has successfully accomplished the task of carrying out combinatorial selection to isolate lanthanide-dependent RNA-cleaving DNAzymes. We report two new DNAzymes, each discovered in a different selection condition and both are highly specific to lanthanides. When both DNAzymes are used together, it is possible to identify the last few heavy lanthanides. Upon introducing a phosphorothioate modification, one of the abovementioned DNAzymes becomes highly active with many toxic heavy metals. With the selection of more DNAzymes with different activity patterns cross the lanthanide series, a sensor array might be produced for identifying each ion. This article is a minireview of the current developments on this topic and some of the historical aspects. It reflects the main content of the Fred Beamish Award presentation delivered at the 2014 Canadian Society for Chemistry Conference in Vancouver. Future directions in this area are also discussed.

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