Nutrient effects on ten Streptomyces spp. sporulation

The effects of nutrients on sporulation of ten Streptomyces spp. was studied on 26 media. The media included starch-casein-KNO3, glycerol-arginine (GA), actinomycete-isolation (AI), tryptone-yeast extractglucose (TYG), and tryptone-soy agars. Media compositions had complicated effects on sporulation. The sporulation on media with minerals of GA agar and yeast extract was usually better than on media with minerals of AI agar. Glycerol often decreased sporulation, although GA agar was among the best media for sporulation. The average sporulation on media with Na-caseinate and asparagine was better than on same media with NH4NO3, however, a medium with Na-propionate, NH4NO3 and yeast extract was among the best for sporulation. At pH 5.5 on TYG-agar with minerals of GA agar instead of yeast extract all strains completely covered mycelium with spores. The sporulation capacity of strains was excellent, the mean mycelium area covered with spores on 26 media being 78 % in fourteen days. When environmental streptomycetes are able to germinate, grow, and then sporulate, they likely form a great amount of spores independent of growth conditions.