Production of B-group vitamins by Azospirillum spp. grown in media of different pH at different temperatures.

Studies were carried out on B-group vitamin (thiamine, biotin, nicotinic acid, riboflavin, pantothenic acid) production by 3 strains of Azospirillum (one derived from coniferous ectomycorrhizae and two--from sporocarps of ectomycorrhizal fungi) grown in media of different pH (5.5, 6.5, 7.5) at different temperatures (10 degrees C, 20 degrees C, 26 degrees C). Riboflavin was produced in largest amounts by all the strains studied; biotin was not detected in culture filtrates at all. Qualitative-quantitative composition of vitamins in post culture liquids of azospirilla depended on the temperature of growth, pH of the medium and on the strain studied. Thiamine was synthesized in largest quantities at pH 5.5 by all strains of Azospirillum--independently of the temperature of growth. In media of higher pH this vitamin was detected in considerably smaller amounts or was not detected at all. The smallest quantities--and the smallest numbers of vitamins produced were observed at temperature 10 degrees C and pH 5.5.