Culture medium is a nutrient matrix prepared by artificial methods according to various nutrients needed for biological growth and reproduction. It contains carbon source, nitrogen source, inorganic salt, vitamins and water. The growth and reproduction of microorganisms on the culture medium must be in the best pH range to grow better.
There are many kinds of media, and different microorganisms need different media. According to physical properties, it can be divided into three types: liquid, solid and semi-solid. Solid culture medium is added with 1.5%-2% agar, and semi-solid culture medium is added with 0.2%-0.5% agar. Agar, also known as agar or watercress, is processed from seaweed, which has stable chemical properties and cannot be decomposed and utilized by ordinary microorganisms. It is dissolved in hot water at 95℃ and solidified again when it is cooled below 45℃, so it is often used as a coagulant in general experiments.
Chinese name potato glucose agar medium mbth potato glucose agar
According to the different sources of nutrients, culture media can be divided into three types: natural, semi-synthetic and synthetic. Natural culture medium is made of natural organic materials after sterilization, such as potato, carrot fruit, barley grain, sorghum grain and so on. Semi-synthetic medium contains some natural organic substances and some compounds with simple or definite components. Such as potato glucose medium (PDA) and peptone medium (sodium). The synthetic medium is composed of some compounds with definite components, and there is no substance with unclear components. It is often used to study the physiological and biochemical characteristics of microorganisms, such as Czapek medium.