新闻资讯/NEWS
|
|
Industrial fermentation sterilization methods: thermal sterilization, radiation sterilization, chemical sterilization, filtration sterilizationconceptual analysis Disinfection: Using physical or chemical methods to kill all pathogenic microorganisms (surfaces) in materials, containers, and the environment can generally only kill nutrient cells and cannot kill bacterial spores. Sterilization: To kill or remove all microorganisms using physical or chemical methods. Sterilization: Using filtration methods to remove microorganisms or spores from air or liquid. Category: Heat sterilization method, radiation sterilization method, chemical sterilization method, filtration sterilization method.
1、 Thermal sterilization method 1. Dry heat sterilization Concept: Heating inside equipment under the action of infrared or electric heating, mainly used to sterilize dry materials, utensils, etc. Method: Commonly used in an oven, with a temperature of 160-170 degrees Celsius maintained for 1-2 hours. Attention: The temperature should not exceed 180 degrees, sterilized objects should not be placed too tightly, cooling should be done slowly, and the oven door can only be opened when the temperature drops below 80 degrees. Disadvantages: The penetration of dry heat is weak, and microorganisms are subjected to much stronger forces on dry heat than on wet heat. The required sterilization temperature is higher and the time is longer. Flame sterilization: Using flames to directly kill microorganisms. The sterilization of inoculation needles, inoculation rings, etc. is limited in its application scope
2. Damp heat sterilization Concept: By utilizing the heat released by steam, chemical bonds, especially hydrogen bonds, within proteins, nucleic acids, and enzyme molecules in microbial cells are disrupted, causing irreversible denaturation and leading to microbial death. Thermal resistance: the lethal time of microorganisms under a certain condition. Scope: Widely used for sterilization of production equipment and culture media.
Compared to dry heat sterilization, the sterilization effect is stronger at the same temperature. Reason: (1) Under humid and hot conditions, the bacterial body absorbs water, making it easier for proteins to coagulate. Due to the increase in water content, the required solidification temperature decreases (2) the penetration force of humid steam is greater (3) there is latent heat in humid steam. Wet heat sterilization categories: boiling sterilization method, pasteurization method, intermittent sterilization, high-pressure steam sterilization method, etc.
Bailun GMP vaccine fermentation tank (fully automatic sterilization) Boiling method Boil the items to be disinfected in water at 100 degrees Celsius. Boiling time: 15-20 minutes, killing microbial nutrient cells. 1-2 hours, kill spores, add sodium carbonate or carbolic acid (0.5%). Object: Suitable for disinfection of food or equipment. Pasteurization method The object to be disinfected should be heated at 60-62 ° C for 30 minutes or 70 ° C for 15 minutes to kill pathogens and some microorganisms. Target audience: Foods such as milk, beer, yellow wine, soy sauce, etc. Features: It does not harm the nutritional value, color, aroma, or taste of certain foods. Example: Sterilization of beer. Intermittent sterilization method Using repeated atmospheric steam sterilization methods to kill microbial nutrients and spores.  Bailun 30TGMP bioreactor (fully automatic sterilization) Advantages and disadvantages of moist heat sterilization Advantages: Easy steam source, strong steam penetration, thorough sterilization, high latent heat of steam, and adjustable pressure. Disadvantage: The equipment cost is high and cannot be used for sterilization of materials that are afraid of moisture. 2、 Radiation sterilization method Concept: Using high-energy electromagnetic radiation and particulate radiation to kill microorganisms. Ultraviolet rays are the most commonly used. Applicable to: vaccination room, ultra clean workbench, sterile culture room, and material surface. Attention: UV penetration rate is low and can only be used for surface sterilization. A 30W ultraviolet lamp can be irradiated for 30 minutes to achieve bactericidal effect. Generally used in combination with chemical reagents. Principle: Causing the DNA strand of microorganisms to break, disrupting the connection between ribose and phosphate, resulting in the breaking of hydrogen bonds within or between DNA molecules, leading to microbial death.
3、 Chemical sterilization method Concept: The method by which chemical drugs directly act on microorganisms to kill them. Scope: Disinfection of production workshops, sterile rooms, laboratories, small instruments and hands before vaccination. Method: Soak, add, wipe, spray, etc. Principle: Chemical substances are prone to react with certain components in microbial cells. Such as protein denaturation, inactivation of obscure substances, disruption of cell membrane permeability, and killing microorganisms. Note: Not suitable for sterilization of culture media, suitable for sterilization of local spaces or instruments.
4、 Filtration and sterilization method Concept: Utilizing the principle that bacteria cannot pass through dense porous filter materials to remove microorganisms from gases or liquids. Scope: Commonly used for sterilization of gas, thermally unstable pharmaceutical solutions or raw materials. Mainly used for sterilization of heat-resistant biological products such as serum and antibiotics, as well as air. Instruments: The instruments used are bacterial filters with small pore sizes. The commonly used filters include membrane filters (0.45 μ m and 0.22 μ m pore sizes), ceramic filters, asbestos filters (i.e. Seitz filters), sintered glass filters, etc. The filtration and sterilization methods are divided into absolute filtration and deep filtration. Absolute filtration: It is the process of intercepting particles when the filter hole of the filtering medium is smaller than that of solid particles. Deep filtration: The filter pores of the medium are not necessarily smaller than solid particles. It intercepts particles through the winding channels inside the filter layer.
|
