1. Experimental principle The main component of Trizol is phenol. The main function of phenol is to lyse the cells and release the nucleic acid substances in the cells. At the same time, although phenol can effectively denature proteins, it cannot completely inhibit RNase activity. Therefore, 8-hydroxyquinoline, guanidine isothiocyanate, β-mercaptoethanol, etc. are added to Trizol to inhibit endogenous and exogenous RNase (RNA Enzymes). 0.1% 8-hydroxyquinoline can inhibit RNase, and combined with chloroform can enhance the inhibition. Guanidine isothiocyanate is a decoupling agent. It is a kind of powerful protein denaturant. It can dissolve protein and make the secondary structure of protein disappear, resulting in the degradation of cell structure. The main role of β-mercaptoethanol is to break the disulfide bonds in RNase protein. After the sample treated with Trizol reagent was added to chloroform, the sample was centrifuged into a water sample layer, an intermediate layer and an organic layer. RNA is present in the water sample layer. After collecting the water sample layer, RNA can be precipitated by isopropyl alcohol. 2. Experimental reagents Trizol reagent, DEPC, chloroform, isopropanol, DEPC treated water, 75% ethanol (prepared by DEPC water), Lactobacillus plantarum 05-19 3. Experimental instruments Constant temperature incubator, room temperature centrifuge, low temperature centrifuge, pipette, electrophoresis instrument, electrophoresis tank, ultraviolet analyzer 4. Operation steps Then connect Lactobacillus plantarum in MRS liquid medium and cultivate overnight in a 37 ° C incubator for use. Take 2ml of the bacterial solution, centrifuge at 12000rpm for 2 minutes, discard the supernatant, add 1ml of Trizol reagent, blow it with a gun, suspend the bacteria, and leave it at room temperature for ten minutes. Add 200ul of chloroform, cover the centrifuge tube tightly, shake vigorously by hand for 15 seconds, and centrifuge at 12000rpm for 4 minutes at 4 ° C. Take the supernatant (approximately 500ul), add an equal volume of isopropanol, leave at -20 ℃ for ten minutes, and centrifuge at 12,000rpm for 4 minutes at 4 ℃. Discard the supernatant, add 1 ml of 75% ethanol, mix well, and centrifuge at 12,000 rpm for 5 minutes at 4 ° C. Carefully discard the supernatant and dry it at room temperature for 5-10 minutes, taking care not to over-dry it, otherwise it will reduce the solubility of RNA. The RNA was then dissolved in 15ul of DEPC treated water. Perform agarose gel electrophoresis and store the remaining RNA at -70 ° C. Experimental considerations Disposable masks and gloves should be worn during the entire operation, and the operation should be performed at the lowest possible temperature. After adding chloroform, first mix well. When drawing the supernatant, be careful not to suck into the middle layer and organic phase. Use RNase-free plastic products and pipette tips to avoid cross-contamination Use RNase-free water to prepare the solution. Three promotions,High Quality Three promotions,Three promotions Details, CN ZHEJIANG HUZOLI METAL PRODUCTS CO.,LTD , https://www.zlplasticfurniture.com