The main factors affecting seed tank culture include: nutrient conditions, culture conditions, control of bacterial infection, determination of expansion grades and determination of inoculum size. 1 medium The acquisition of nutrients in the medium has a direct impact on the growth, reproduction, enzyme activity and yield of microorganisms. The medium can be divided into C/N basic growth nutrition, inorganic salt osmotic pressure control, trace element maintenance composition, and pH enzyme activity regulation system. The requirements of the medium are simple in composition, rich in source, cheap in price, and convenient to take. Note: 2 years old, inoculum Age requirement: transplanting in logarithmic growth phase, because the start-up speeds of tender and old cans are slower, which leads to an increase in fermentation cycle and low yield. Look at the temperature in the early stage and see dissolved oxygen in the later stage. Any microorganism has its optimum temperature range, as follows In the biological range, for every 10 °C increase, the growth rate of microorganisms can be doubled, and the temperature directly affects the cell metabolism enzyme system. In the optimal range, increasing the temperature in the early phase of the logarithmic growth phase is beneficial to the synthesis of the cells. In the late logarithmic growth phase, the dissolved oxygen has a greater influence on the rate of bacterial synthesis. At this time, it is necessary to increase the aeration and agitation. 4 pH effect The anion (acetate, phosphate) is absorbed or the nitrogen source is utilized to produce NH3 to raise the pH; Ventilation, tank pressure and agitation together determine the current dissolved oxygen state. Only when dissolved oxygen is greater than the current BOD, can it grow normally today. After transplanting, the bacteria enter the logarithmic growth phase, and the rate of division and reproduction increases. The ventilation volume and stirring power should be alternately adjusted to achieve the required standard of the bacteria. Once the bacteria can not be properly cooled, the rate of oxygen consumption of the cells can be reduced. At this time, the efficiency of cell division growth is reduced but not caused by hypoxia. Or autolysis. The less the technology, the less susceptible to bacterial infection, the number of grades determined by the nature of the strain, such as growth rate, logarithmic bacterial concentration, spore development level, etc., after continuous optimization and debugging, the expansion of the seed tank level should be reduced as much as possible. The number is required, provided that it does not affect or less affect the increase in the production tank lag period and the growth rate in the logarithmic growth phase. Shaanxi Kang New Pharmaceutical co., Ltd. , https://www.kangnewpharmas.com
The final stage of the A seed tank is consistent with the production tank. At this time, the former tank has established the enzyme system required for fermentation, and no rebuilding is required under the new environmental conditions;
B seed tank culture medium should increase the amount of N, and the proportion of inorganic nitrogen increase should be larger;
After the C strain is advanced, due to equipment differences (can type, agitation form, rotation speed, etc.), the medium ratio needs to be re-adjusted according to the experiment.
Inoculation amount: The amount of inoculation affects the length of the lag phase in the new environment. This is because the inoculum is accompanied by metabolites such as RNA required for cell division and reproduction. The content of such substances can quickly enter the logarithmic growth phase, so the inoculum and new environment The lag phase is inversely proportional.
3 temperature 
The cation (NH4+, K+) is absorbed or the organic acid is accumulated to lower the pH;
High C medium pH moves to low pH;
The high N medium pH moves to a high pH.
Three ways to adjust pH: a acid-base solution; b buffer; c buffer (acid or alkaline salt)
5 ventilation mixing
6 seed tank series determination