Nitrate reduction test

The nitrate reduction test is based on the ability of certain bacteria to reduce nitrate to nitrite, nitrite and acetic acid to form nitrous acid, nitrous acid and p-aminobenzenesulfonic acid in the reagent to form diazobenzenesulfonic acid. A test method for the principle of combining N-naphthylamine sulfonic acid with α-naphthylamine. Basic Information Specialist classification: growth and development check classification: biochemical examination Applicable gender: whether men and women apply fasting: fasting Tips: Pay attention to normal eating habits and pay attention to personal hygiene. Normal value The type and proportion of the flora in the body are normal, and the human body is in a dynamic balance. Clinical significance This test is widely used for bacterial identification. Enterobacteriaceae bacteria can reduce nitrate to nitrite; some bacteria in Pseudomonas can produce nitrogen, such as Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Pseudomonas stutzeri, The nitrate can be reduced to nitrite, such as Pseudomonas sinensis; anaerobic bacteria such as Weirong can also reduce nitrate to nitrite. Abnormal result Enterobacteriaceae bacteria cause extraintestinal infections. Urinary tract infections are common. Opportunistic diseases can cause suppurative inflammation, such as cholecystitis, peritonitis, pneumonia, meningitis and sepsis. Pseudomonas aeruginosa is infected with gangrenous deep impetigo, green nail syndrome, otitis externa, and folliculitis. There are also some diseases caused by certain anaerobic bacteria. Precautions Inappropriate crowd: No. Forbidden before examination: Pay attention to normal eating habits and pay attention to personal hygiene. Requirements for inspection: Actively cooperate with the doctor. Test judgment requirements: The nitrate reduction process may vary from bacteria to bacteria. Some bacteria only reduce nitrate to nitrite, such as Escherichia coli, some bacteria can reduce it to nitrite and ionic ammonium, and some bacteria can reduce nitrate or nitrite to Nitrogen, such as Serratia, and some bacteria can also fully utilize their reduced products in synthetic metabolism. The test shall be judged based on the test results, and the interference shall be excluded. Inspection process Reagent A liquid: aminobenzenesulfonic acid 0.8g5mol / L acetic acid 100ml Liquid B: α-naphthylamine 0.5g5mol/L acetic acid 100ml Nitrate reduction test method The test bacteria in the culture solution to be inspected were inoculated into a nitrate medium (containing a small inverted tube), and incubated at 35 ° C for 1 to 4 days. 0.1 ml of a mixture of A and B (mixed with time) was added to the test tube, and the result was observed immediately or within 10 minutes. When doing this test, a medium that is not inoculated with bacteria should be used as a control test, and only when the control tube is negative, can it be judged. result Red is positive. If you want to observe the presence or absence of nitrogen, you can add a small inverted tube to the medium tube. If there is a bubble, it means that nitrogen is formed. If you want to check whether the nitrate in the medium is decomposed, you can add a little zinc powder to the medium. If red appears, the nitrate is still present. If it does not appear red, the nitrate has been decomposed. Not suitable for the crowd no. Adverse reactions and risks no.