(1) batch culture

In a relatively independent and closed system, the method of inoculating and cultivating microorganisms with culture medium at one time is generally called batch culture. Because its culture system is relatively closed, batch culture is also called closed culture. For example, in microbial research, microbial culture with shake flask as culture container is generally batch culture. By adopting this batch culture method, with the extension of culture time, due to the relative tightness of the system, the nutrients consumed by microorganisms can not be replenished in time, the metabolites can not be discharged from the culture system in time, and other environmental conditions that inhibit the growth of microorganisms can not be improved in time, which makes the nutritional conditions and external environment required for the growth and reproduction of microbial cells deteriorate gradually, so that the growth of microbial groups presents a distinct group growth from the adaptation of cells to the new environment to the gradual rapid growth, to the stable period, and finally to the decline and death stage. In the past, batch culture was used to study the growth curve. Because it is difficult to prolong the important stage of growth, batch culture has obvious characteristics of batch and short cycle. Because batch culture is relatively simple and easy to operate, it is still widely used in microbiology research and fermentation industrial production practice.

(2) continuous culture

Continuous culture of microorganisms is relative to batch culture. Continuous culture refers to the culture mode of opening the culture system, constantly supplementing nutrient solution, removing inhibitory factors and optimizing the growth and metabolic environment on the basis of in-depth study of the internal mechanism of growth curve formation in batch culture. Because the cultural system is relatively open, continuous culture is also called open culture. The remarkable feature and advantage of continuous culture is that it can artificially control a certain period in the typical growth curve to some extent according to the researcher's purpose, thus shortening or prolonging the time, accelerating or reducing the metabolic rate of cells in a certain period, thus greatly improving the artificial controllability and efficiency of the culture process.