GB854918A - Azotobacter concentrates obtained by submerged aerobic fermentation - Google Patents

Abstract

A concentrated azotobacter culture for use in soil bacterizing and fodder preparations is obtained by preparing a sterile culture medium from nutrients and assimilable carbonaceous waste material free or substantially free of nitrogen, diluting same with sterile water, adding thereto sterile magnesium carbonate and a sterile adsorbent, stirring, inoculating with an azotobacter culture with simultaneous aeration, fermenting until substantially all carbonaceous waste material has been utilised and thereafter adding a further quantity of said culture medium, magnesium carbonate and adsorbent, allowing fermentation to proceed at a pH value of 6,5 to 7,0 with aeration until substantially all the carbon source has been utilised and separating, washing and rethickening the mature mash twice to obtain a bacterial concentrate. In the sample, the culture medium contains glucose waste (74,4% glucose, 18,5% dextrin and 0,032% nitrogen in a solids content of 94,8%) KHPO4, K2HPO4, MgSO4, NaCl, CaSO4, sodium molybdate and water and magnesium carbonate and activated carbon is added. In place of the glucose waste, there may be used waste starch, starch refuse, syrups and waste waters containing such materials. Other adsorbents are bone dust, kaolin, Fuller's earth and silica gel. The temperature of cultivation is 25 to 30 DEG C. and the duration 36 to 48 hours. The final culture may be used to inoculate a fresh batch of culture medium. A soil bacterizing preparation is produced by mixing the final culture with sterile humus soil, kaolin or fuller's earth in proportions of 1 to 20 to 1 to 100. In the case of an animal feed, the final culture is mixed with animal fodder.ALSO:A concentrated azotobacter culture for use in soil bacterizing and fodder preparations is obtained by preparing a sterile culture medium from nutrients and assimilable carbonaceous waste material free or substantially free of nitrogen, diluting same with sterile water, adding thereto sterile magnesium carbonate and a sterile adsorbent, stirring, inoculating with an azotobacter culture with simultaneous aeration, fermenting until substantially all carbonaceous waste material has been utilised and thereafter adding a further quantity of said culture medium, magnesium carbonate and adsorbent, allowing fermentation to proceed at a pH value of 6,5 to 7,0 with aeration until substantially all the carbon source has been utilized and separating, washing and re-thickening the mature mash twice to obtain a bacterial concentrate. In the example, the culture medium contains glucose waste (74,4% glucose, 18,5% dextrin and 0,032% nitrogen in a solids content of 94,8%) KHPO4, K2HPO4, MgSO4, NaCl, CaSO4, sodium molybdate and water and magnesium carbonate and activated carbon is added. In place of the glucose waste, there may be used waste starch, starch refuse, syrups and waste waters containing such materials. Other adsorbents are bone dust, kaolin, Fuller's earth and silica gel. The temperature of cultivation is 25 to 30 DEG C. and the duration 36 to 48 hours. The final culture may be used to inoculate a fresh batch of culture medium. A soil bacterizing preparation is produced by mixing the final culture with sterile humus soil, kaolin, or Fuller's earth in proportions of 1 to 20 to 1 to 100. In the case of an animal feed, the final culture is mixed with animal fodder.