Ultraviolet sterilizing is carried out by ultraviolet light. The ultraviolet ray with a wavelength of 200~300 nm has bactericidal ability, and the sterilizing power of 260 nm is the strongest. Under certain wavelength conditions, the sterilization efficiency of ultraviolet light is proportional to the product of intensity and time. The UV sterilizing mechanism is mainly because it induces the formation of thymine dimer, thereby inhibiting DNA replication. Pickled Beefsteak,Frozen Pickled Beefsteak,Seasoned Pickled Beef Cubes,Fillet Steak ZHOUSHAN GENHO FOOD CO.,LTD , https://www.genho-food.com experimental method
Principle of experimental method Since radiation can ionize oxygen in the air to [O], O 2 is oxidized to form ozone (O 3 ) or water (H 2 O) is oxidized to form hydrogen peroxide (H 2 O 2 ), O 3 and H 2 O 2 has a bactericidal effect. UV penetration is not large, so it is only suitable for sterilization in the sterile room, inoculation box, air in the operating room and surface of the object. The UV lamp should be no more than 1.2 m from the irradiated material. Reagents, kits Instruments, consumables Experimental procedure
(1) Turn on the UV lamp switch in the sterile room or in the inoculation box, and illuminate for 30 minutes to turn off the switch.
(2) The beef paste peptone lid was opened for 15 minutes, then the lid was placed and incubated at 37 ° C for 24 hours. Do a total of three sets.
(3) Check the number of colonies growing on each plate. If there are no more than 4, the sterilization effect is good. Otherwise, it is necessary to extend the irradiation time or strengthen other measures at the same time.
2. Chemical disinfectant combined with UV irradiation
(1) In a sterile room, spray 3 to 5% of a solution of carbolic acid and then irradiate with an ultraviolet lamp for 15 minutes.
(2) The tabletop and stool in the sterile room are scrubbed with 2~3% to Sur, and then the UV lamp is turned on for 15 minutes.
(3) Check the sterilization effect.
Because ultraviolet light has a damaging effect on the conjunctiva and optic nerve, it has a stimulating effect on the skin. Therefore, it is not possible to look directly at the ultraviolet light, and it is not possible to work under ultraviolet light.
Microbiology Technology: UV Sterilization Experiment
Carbolic acid to sul solution beef paste protein plate
ultra violet light
1. Single ultraviolet radiation