Reasons for changes in the physiological condition of bacteria

Microbial fermentation channel: the genetic characteristics of the bacteria need to be shown under certain conditionsBecause the culture condition is not appropriate, so that the bacteria in the physiological condition is not conducive to fermentation production, the results are also shown as the decline of the bacteriaThere are three reasons why the physiological condition of the bacteria is not conducive to fermentationa strain is not a pure group, but is made up of a mixture of mutant strains whose proportion determines the characteristics of the speciesA single colony is isolated on a solid medium and can grow many forms of cultured coloniesThese different colony types differ in metabolism and growth and reproductionCulture conditions can affect the proportion of each mutant strain in culture and change the characteristics of the strainThe single spores of the same species were isolated on different media, and the single colonies grown had significant differences in morphological culture characteristics, and the proportion of various types of colonies was also differentFor example, streptomyces griseus on a pea agar medium, monospore separation showed 3 to 4 types of colonies, while only two colony types appeared on the soybean powder mediumIn the beginning of the selection of bacteria, we should study the separation of the single colony's isolated media, to find out the separation medium that can present more types of coloniesThere is a certain correlation between the type of colony and fermentation yieldIn the selection practice, people after the study of the form of colonies, consciously discard some of the colonies that are considered low-yielding, and select those that may be high-yieldingbacterial medium can affect fermentation yield by affecting the physiological condition of the speciesToo rich in the nutrients of the bacterial medium is not conducive to the formation of spores, and thus affects fermentationThe nutrient deficiency of the bacterial medium is also not conducive to fermentationBecause the bacteria in the nutrient-poor medium many times passed on, will make the bacteria cells lack certain growth factors and aging and even deathTherefore, the medium used in natural breeding or spoof culture should choose the medium with the reduction of production capacity after the spread of the bacteria, the bacteria is not easy to age and self-soluble normal form of colonies, spores rich medium under certain culture conditions, some genes of the bacteria are in a state of activation or deterrence, and the physiological state of the bacteria changes This change may be maintained for a longer period of time with a mechanism similar to physiological delay or cell differentiation because the decline of the bacteria will cause a sharp decline in the production of fermentation process, once the decline of the strains, it is necessary to take effective prevention and prevention measures to prevent the deterioration of the good characteristics of the species At the same time, if some good characteristics of degradation is found, should be timely separation purification, so that the production of bacteria to maintain a stable good characteristics The measures to prevent the decline of the bacteria mainly include the rehabilitation of the species, the provision of good environmental conditions, the regular purification of the bacteria, the prevention of their own mutation and other aspects