Production of Flavour‐enhancing Materials by Streptomycetes: Screening for 5′‐Nucleotides

Abstract

Summary. Streptomycetes were examined for their ability to accumulate flavour‐enhancing nucleotides. An efficient screening programme was devised for the isolation of streptomycetes excreting 5′‐nucleotides. Less than 0.7% of these organisms isolated from nature showed appreciable extracellular accumulation of 5′‐nucleotides, and streptomycetes derived from culture collections gave none. In shake flask experiments the yields of nucleotides were minimal and did not exceed (g/l) 0.2 of inosine 5′‐monophosphate, 0.15 of xanthosine 5′‐monophosphate, and 0.05 of guanosine 5′‐monophosphate.

Production of Flavour‐enhancing Materials by Streptomycetes: Factors affecting the Production 5′‐Mononucleotides

“…Fermentation broths were analysed in duplicate by W absorption, paper chromatography and specific chemical reactions to identify the products, as described previously (Schwartz & Margalith, 1971). For approximate evaluation of nucleotide production, only UV absorption was recorded.…”

“…The production of 5'-mononucleotides by 5 strains selected from the screening programme (Schwartz & Margalith, 1971), was compared in 2 media (A) production medium ; (B) production medium supplemented with trace elements, Mn++, Cu++, Zn++ as sulphates, and Go++ as chloride, each a t 1.0 pg/ml. Three strains, nos.…”