University:
Northwest College
Course:
MOLB-2210 | General Microbiology
Academic year:

2023
Views:

369

Pages:

1
Author:

J cyrus

Media Media is a nutrient solution used to grow microorganisms in the laboratory. Media are eeded to study microorganisms well, therefore special attention is needed in media selection and preparation. Media can be structured and complex. Structured media is prepared by adding pure chemical substances, both organic and inorganic, in appropriate amounts to distilled water. The chemical composition of the medium is known precisely therefore it is called a structured medium. Each medium contains a carbon source because microorganisms need a lot of carbon to make new cellular materials. In simple structured media there is a single carbon source. The nature and concentration of the carbon source depends on the microorganisms to be cultured. To grow various microorganisms the exact composition of the media is not always necessary. In this case, complex media can be used and are more profitable. Complex media can contain plant or animal materials such as milk casein (milk protein), meat, soybeans, yeast cells or other substances of high nutritional value. Often media materials are available in powder form so they are easy to weigh and dissolve in distilled water. In certain circumstances, for example in clinical microbiology, media often have to be selective or differential. Selective media contain compounds that can selectively inhibit some microorganisms and some not. Differential media contain indicators, for example dyes, that allow differentiation of the chemical reactions that take place during the growth of microorganisms. Differential media can be used to differentiate between species of microorganisms that can carry out a reaction and those that cannot. Complex media are easier to prepare and can support the growth of organisms such as the enteron bacteria Escherichia coli, lactic acid bacteria Leuconostoc mesenteroides which are fastidious bacteria. Simple structured media can also be used to grow Escherichia coli well but not L. mesenteroides, because it requires several organic compounds and growth factors that E. coli does not need. Between the two bacteria, which one has the greater biosynthetic capacity? The answer is of course E. coli because it is able to grow on simple, synthetic structured media organic components of simple carbon compounds such as mesenteroidesglucose, otherwise L.requires many growth factors and organic nutrients such as amino acids, thus showing limited biosynthetic capacity. Several pathogenic microorganisms such as Streptococcus pyogenes, Neisseria gonorrhoeaeoften require enriched media, namely complex media plus serum or blood, similar to the conditions found in the host so that they can be grown well in the laboratory. From the description. It can be said that different microorganisms require different nutrients, therefore, to grow certain microorganisms, it is necessary to know the nutritional requirements to provide appropriate nutrients in both form and quantity.