Economic liquid growth medium development for high-rate production of cellular biomass and lactic acid of Lactococcus lactis

<p><em>L.lactis</em> importance in the alimentary and pharmaceutical industry as a lactic acid and nisin production strain has been well<br>established. However for its growth, nutrient media such as M17 and Man de Rogosa Sharp (MRS) are used, which are not suitable for use in large quantities due to the high preparation cost and content of nitrogen sources of beef extract and<br>peptone from poultry that are not environmentally friendly and have possible health risks. For its intensive propagation and high rate lactic acid production an economic liquid growth medium was formulated, using <em>Lactococcus lactis</em> NCIMB<br>700185. To test medium efficiency, the coccus was grown in a 2 L CSTR with continuous temperature and pH control.The developed medium supported evenly cellular growth offering elevated maximum yields incorporating only the chemicals compounds needed, resulting in an improvement of the growth rate of the coccus of 70.6%, when compared to<br>the same strain on MRS, the lactic acid concentration produced was 30.28 g L-1.</p> <p>Keywords: Lactic acid bacteria, Lactococcus lactis, Nutrient media, Biomass, Fermentation, Lactic acid