[Blood hydrolysates for microbiological culture media].

Blood hydrolysates contain two times less nucleic acids than meat hydrolysates, the levels of vitamins B2, B3, B6, and B9 are lower in them either. The authors suggest that this is the cause of a poorer growth of microorganisms in culture media with blood hydrolysates, repeatedly reported in literature. They have demonstrated that addition of nucleic acids and vitamins to blood hydrolysates improves the microorganism growth.

[Use of substances stimulating enterobacteria growth in obtaining microbial adsorbents].

The combination of substances, capable of stimulating the growth of enterobacteria and consisting of reducing agents (sodium thiosulfate and sodium sulfate), the vitamin preparation of yeast extract, polyatomic alcohol (glycerol) and ion exchange resin AB-17-8, is proposed. The addition of this combination of substances to culture media based on clots of animal blood has made it possible to achieve more intensive growth of Escherichia and Proteus than on classical meat culture media.

[Comparative study of the physico-chemical properties of peptones used to the production of dry alkaline agar for cholera diagnosis].

The authors present the results of chemical and physico-chemical study of dry peptones (made in the USSR) used in the production of dry alkaline nutrient agar for the diagnosis of cholera, in comparison with peptones used for other purposes. The batches and types of peptones studied differed by the fractional peptide composition and by the physico-chemical characteristics. Positive results were obtained in the biological test in using peptones with marked hydrolysis with the amine nitrogen content of not less than 200--230 mg%, with an elution curve approaching the Hottinger's peptone curve, well soluble in buffer phosphate solution at 5% concentration.