title: Valine production from hydrocarbon by Micrococcus varians.
abstract: A bacterium isolated from Assam (India) soil was found to accumulate L-valine in the growth medium and was identified as Micrococcus varians. The strain grew and accumulated valine in a purely synthetic medium, but supplementation with either casamino acids or yeast extract or with both, improved the yield. The entire fermentation period could be divided into a growth phase and a production (phase which could be prolonged by adjustment of pH to neutral range. Among the different hydrocarbon and nitrogen sources tested straight run gas-oil and ammonium sulphate, respectively, were found most suitable. Antibiotics inhibited growth but stimulated extracellular valine accumulation. Vitamins stimulated growth and valine yield and an inoculum level of 10% was found to be optimal. The yield of L-valine under optimal conditions was 2.95 g/L.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003470:Culture Media; D006838:Hydrocarbons / Q000378:metabolism*; D008837:Micrococcus / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D011136:Polysorbates / Q000494:pharmacology; D014633:Valine / Q000032:analysis / Q000096:biosynthesis*; D014815:Vitamins / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D006838:Hydrocarbons; D011136:Polysorbates; D014815:Vitamins; D014633:Valine