[Search for lactate oxidase producer microorganisms].

Using the method of enrichment cultures, eight lactate oxidase producer strains of the fungus Geotrichum candidum were identified. The microorganisms were isolated from diverse specimens of fermented vegetables and manure. Variation in the content of glucose and lactate and the degree of aeration made it possible to attain lactate oxidase activities of up to 130-140 U per 11 grown medium containing microbial cells.

[Search for micromycetes--producers extracellular catalase and study of conditions of its synthesis].

Production of extracellular catalase by microscopic mycelial fungi (255 strains) belonging to different taxonomic groups was studied. Producers of extracellular catalase were found among fungi of the genera Penicillium, Talaromyces and Aspergillus. Strains of the genus Penicillium were the most active producers.

[Results of the storage of freeze dried microbial cultures for 25 years].

Saprophytic microorganisms belonging to different physiological groups (Azotobacter, acetic, ammonifying, lactic and nodule bacteria, a phototrophous purple bacterium of the Chromatium genus, bacteria of the Micrococcus and Pseudomonas genera, and a yeast of the Candida genus) were stored at 3-6 degrees C for 25 years in the freeze-dried state. All of the strains were found to be viable after the storage. The number of viable cells decreased for some bacteria, but to a far less degree than when the cultures were kept immediately after the freeze-drying for a year at 30 degrees C.

[Synthesis of tyrosine and 3,4-dihydroxyphenylalanine by Citrobacter freundii bacteria from lactic acid].

A possibility of using lactic acid as a precursor for the synthesis of L-tyrosine and L-3,4-dihydroxyphenylalanine (DOPA) by Citrobacter freundii 62 and 63 was established. The synthesis of tyrosine from lactic acid occurs at a phenol concentration of less than 0.6%.