◆ Difference: First of all, there are microorganisms in both solid and semi-solid media, and the main components are water, inorganic salts, growth factors, carbon sources and nitrogen sources. If it is a virus, it should be cultured with bacteria; For animals, it is best to use natural culture medium containing growth factors, usually liquid culture medium, which mainly contains water, glucose, amino acids, inorganic salts, vitamins and animal serum; The plant culture medium can be a synthetic culture medium, generally a solid culture medium, and its components are mainly mineral elements, sucrose, cellulose, plant hormones and organic additives. Secondly, the principles of their respective cultures are different. The principle of microbial cell culture is the proliferation of microbial cells, the principle of animal cell culture is the proliferation of cells and the principle of plant cell culture is the totipotency of cells.

Finally, microbial cell culture is mainly to obtain its metabolites or secondary metabolites or to obtain the cells themselves; Plant cell culture is the culture of obtaining new individuals or cell products, applying and rapidly propagating test-tube seedlings, cell products, artificial seeds and transgenic plants. Animal cell culture is to obtain a large number of new cells or cell products, and the application is to obtain cell products or cells. In addition, trypsin is used for animal cell dispersion and cellulase is used for plants.

◆ Similarity: Both of them need culture medium, aseptic operation to prevent bacterial pollution, and the temperature is suitable for cultivation.

◆ In summary, see the table below:

Microbial animal cells and plant cells

Size (um)1~10 ~10 ~100 ~10.

Most cells attached to the surface can grow in suspension, but they are easy to agglomerate and have no single cells.

Nutritional requirements are simple, complicated and complicated.

The growth rate is fast, the doubling time is 0.5~5 hours slower, the doubling time is 15~ 100 hours slower, and the doubling time is 24~74 hours slower.

Metabolic regulation internal internal, hormone internal, hormone

The environment is sensitive, insensitive and very sensitive, and it can be tolerated in a wide range.

There are high and low cell differentiation.

Shear sensitivity is low, very high and very high.

Traditional mutation and screening techniques are widely used, not often used, and sometimes used.

The concentration of cells or products is high or low.

Because they use different culture media and require different culture conditions, it is necessary to choose the corresponding bioreactor when producing the target products we need on a large scale. When selecting bioreactor, we should pay attention to the shear force and mass transfer problems such as gas-liquid mass transfer and liquid-solid mass transfer in the process of biological reaction. Bioreactor is a device which provides a good reaction environment for cell culture (or fermentation) or enzyme reaction by using biocatalyst, and is usually called fermentation tank or enzyme reactor. The aeration tank or anaerobic digestion tank used for biological treatment of sewage can also be used as a kind of bioreactor. Bioreactor is the key equipment in the process of biological reaction, and its structure, operation mode and operating conditions are closely related to the quality, conversion rate and energy consumption of biotechnology products. Now, three kinds of bioreactors will be described.

(1) Select a bioreactor for microbial cell culture.

The main body of biological treatment is all kinds of microorganisms with specific functions. Due to the oxidative decomposition of malodor, microbial cells obtain energy needed by organisms on the one hand, and cell substances needed by cell proliferation on the other hand, thus maintaining normal life activities of cells. Microorganisms have their own metabolism, and metabolic activities are all carried out under the action of enzymes. Only by creating suitable living conditions and giving full play to the role of enzymes can microorganisms grow normally and use odorous substances as energy, carbon and nitrogen sources for growth. Therefore, the selection of microbial cell culture bioreactor must first ensure the basic conditions for microbial growth. According to the characteristics of microbial culture, membrane bioreactor and photosynthetic microbial bioreactor are generally selected.

(2) Selection of bioreactor for animal cell culture.

There are great differences between animal cells and microbial cells, and there are strict requirements for in vitro culture. For example, animal cells are very sensitive to shear force, so it is impossible to choose a reactor with such high shear force as microbial cells. Therefore, the traditional microbial cell bioreactor needs to be reformed before it is applied to animal bioreactor. Animal cell culture can be divided into three types. One is suspension culture, which refers to the process of cell suspension growth in an incubator. Non-adherent cells should be brave. Such cells do not need to adhere to the wall in vitro, and can be suspended in the culture medium by microbial methods. The corresponding reactors that can be selected for this kind of cell culture are: stirred reactor, hollow fiber reactor, ceramic rectangular channel honeycomb reactor and airlift reactor; The other is monolayer culture, which refers to cell culture that must be attached to the surface of solid medium. It is mainly suitable for adherent cells (also called adherent cells), and most animal cells belong to this type. The growth of these cells needs to be attached to some solid and semi-solid surfaces with moderate positive charges. After adherent growth, cells are no longer in their original shape, but are generally single, mainly fibroblast type, epithelial type, wandering type and pleomorphism. Bioreactors that can be selected for this kind of cell culture are: stirred reactor (microcarrier culture), glass bead bed reactor, hollow fiber reactor, ceramic rectangular channel honeycomb reactor and so on. The other is immobilized culture, which is suitable for both adherent-dependent cells and non-adherent-dependent cells, and has the advantages of high cell growth density, strong shear resistance and strong pollution resistance. Bioreactors used for this kind of cell culture include: fluidized bed reactor, solidified bed reactor, etc.

(3) Selection of bioreactor for plant cell culture

Initially, most bioreactors used for plant cell culture used microbial reactors. Because the morphological structure of plant cells is different from that of microbial cells, plant cells are larger than microbial cells and need less oxygen, but they are very sensitive to shear forces, so mixing is more important. At present, due to the development of plant cell suspension technology, the success of single cell culture and the emergence of various new bioreactors, it is possible to continuously culture plant cells in fermentors on a large scale like microorganisms. The reactors used for plant cell culture mainly include stirred and non-stirred bioreactors, as well as plant cell immobilization reactors and membrane bioreactors.

In a word, before choosing the corresponding bioreactor, we should understand the characteristics and precautions of this kind of cell culture in order to choose the corresponding bioreactor.