Requirements for oxygen and inoculum of Ganoderma lucidum cultured in cell shake flasks
The cell shaker is an economical cell culture tool mainly used for cell lines with high oxygen requirements, such as bacteria, fungi, animal and plant cells grown in suspension. This tool is also used in the liquid fermentation of Ganoderma lucidum and the production of strains, and there are certain requirements for oxygen and inoculum during cultivation.
During submerged fermentation, the mycelium grows rapidly, so the oxygen demand is very high. Within 11-18 hours, if the oxygen content in the fermentation broth cannot meet the needs of the growth of Ganoderma lucidum mycelium, it will seriously affect the cells in the shake flask. Mycelial growth.However, in the early stage of fermentation, the amount of mycelium in the fermentation broth is small, so the oxygen demand can also be less.When the hyphae enter the vigorous growth phase, the amount of oxygen required increases,At this time, the ventilation volume of the fermenter should be controlled to about 0.51 (v/v min), that is, about 0.51m of sterile pure air should be introduced into each 1m of fermentation broth per minute.In the later stage of fermentation, the mycelium ages, the metabolic capacity decreases, and the respiration volume also decreases, so the ventilation volume can be appropriately reduced. During the aeration fermentation culture, it is necessary to keep stirring, and stirring can make the oxygen evenly distributed in the fermentation broth. Through stirring, more oxygen can be dissolved in the fermentation broth, and the mycelium is evenly distributed, but the stirring speed should not be too fast, and the mycelium will be easily damaged.
2. Inoculation amount
In liquid submerged fermentation culture, the growth rate of mycelium is related to the amount of inoculum. The larger the amount of inoculum, the faster the growth of the mycelium and the low infection rate of miscellaneous bacteria, but the aging of the mycelium is fast, the amount of inoculation is small, the growth of the mycelium is slow, and the aging of the mycelium is also slow. However, if there is not enough Ganoderma lucidum mycelium in the fermentation broth for a long time, the antibacterial properties will be reduced, so when the inoculation amount is too small, it is easy to infect miscellaneous bacteria.
In addition, the strains used in the liquid culture of Ganoderma lucidum using cell shake flasks must be short in age, vigorous in vitality, and fast in growth.In this way, the fermentation period can be shortened, the economic benefit can be improved, the strains have strong vitality, and the ability to resist miscellaneous bacteria is also strong. Older bacteria, weak vitality, and slow growth are also susceptible to miscellaneous bacteria.