Growth medium nitrogen sources

Fermentation processes need several components as starting materials an inoculum, growth medium (carbon source such as carbohydrates and sugars, and nitrogen source such as ammonium salts), air/gas, and water. To have a successful fermentation, all these components have to be maintained as sterile to avoid contamination. 

Semifermentation Process. In this process, the metaboHc intermediate in the amino acid biosynthesis or the precursor thereof is added to the medium, which contains carbon and nitrogen sources, and other nutrients required for growth and production, and the metaboHte is converted to the... 

Plant and animal cells have numerous chromosomes. Growth rates are relatively slow. A typical nutrient medium will contain a large number of vitamins and growth factors in addition to complex nitrogen sources, because other specialized cells in the original structures supply these needs. A plant or animal cell is not hke a microbial cell in its ability to function independently. 

The nitrogen source in the medium is the amino add glutamate. There are several cations K Mn2, Cn2, Zn2, Mg2, Co2, Fe2, Ca2 Mo6. Phosphate (POi") is the major anionic component. Fumaric add is a TCA cycle intermediate and may improve metabolic balance through the catabolic pathways and oxidation through the TCA cyde. Peptone may improve growth through the provision of growth factors (amino acids, vitamins, nudeotides). 

The chemical environment of the cells has to be considered very carefully. Animal cells do not need only a carbon and nitrogen source. They are dependent on a variety of other compounds (amino acids, vitamins, growth factors etc.).This complexity of requirements of the culture medium and the complexity of the metabohsm hamper not only the development of defined media but... 

Wang JW, Tan RX. (2002) Artemisinin production in Artemisia annua hair root cultures with improved growth by altering the nitrogen source in the medium. Biotechnol Lett 24 1153-1156. 

Clones of duckweed plants were grown axenically in Stewart s growth medium (17) with asparagine at 132.1 mg/L as nitrogen source. Cultures were maintained in 250-mL Erlenmeyer flasks with 100 mL of medium per flask in controlled environment rooms... 

Growth of the Ammonia Fungi (mg Dry Weight of Mycelium 40 ml-1 Medium) in Liquid Media Containing Different Nitrogen Sources... 

Table 4. Effects of feeding of carbon and nitrogen sources on cell growth and the content (C), production (Pn) and productivity (Pv) of ginseng saponin and polysaccharide. The cell culture in a modified MS medium was taken as a control. Cases 1,2 and 3 Sucrose was fed beginning from day 15,18 and 20, while its level was kept below 20,10 and 20 gH, respectively. Cases 4,5 and 6 Feeding of 20 mM nitrate, 10 mM nitrate plus 10 mM ammonium, and 20 mM ammonium on day 15, respectively, where sugar addition was the same as in case 1...

Figure 8.16 Changes in the content of mannan (o) and PolyP(IV) fraction ( ) during growth of Saccharomyces cerevisiae in a Reader medium in the presence (a) and absence (b) of a nitrogen source (Kulaev et al., 1972d).

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