The Cell number (or) biomass of batch culture exhibits curve of
Answers
Tissues and cells cultured on an agar gelled medium form an unorganised mass of cells called callus. Callus cultures need to be subcultured every 3-5 weeks in view of cell growth, nutrient depletion and medium drying. Therefore, calluses are easy to maintain and are most widely used.
Batch Culture
In a batch culture the same medium and all the cells produced are retained in the culture vessel, e.g. culture flasks (100-250 ml), fermenters (variable size) etc. the cell number or biomass of a batch culture exhibits a typical sigmoidal curve, having a lag phase during which the cell number of biomass remains unchanged, followed by a logarithmic (log) phase when there is a rapid increase in cell number and finally ending in a stationary phase during which cell number does not change. The lag phase duration depends mainly on inoculums size and growth phase of the culture from which inoculums is taken. The log phase lasts about 3-4 cell generations (time taken for doubling of cell number), and the duration of a cell generation may vary from 22-48 hr mainly depending on the plant species. The stationary phase is forced on the culture by a depletion of the nutrients and possibly due to an accumulation of cellular wastes. If the culture is kept in stationary phase for a prolonged period the cells may die.
Answer:
S. Sood, ... A. Kumar, in Comprehensive Biotechnology (Second Edition), 2011
2.13.2.2 Healthy and Active Inoculum
In order to achieve exponential phase in less time, microbes should have a short lag period, that is, they take less time to adapt to the environmental conditions. This is possible only with healthy and actively growing microbial growth. Healthy and active growth can be obtained by providing microbes with proper medium, necessary conditions, and a good monitoring system [27, 43]. The initial size of the inoculum influences the duration of the lag period, which is represented by the mathematical equation [16]
where n is the size of inoculum. It has been demonstrated that the expected log value with initial cell number n is always greater than the population with double (2n) initial cell number.