About this test<\/p>\n\n\n\n
What is the purpose of this test?<\/em><\/p>\n\n\n\n The purpose is to determine whether the unknown microbe produces the enzyme hippuricase, which breaks down hippurate to its components ingredients glycine and benzoic acid. <\/p>\n\n\n\n How is the production of hippuricase determined?<\/em><\/p>\n\n\n\n Hippuricase will hydrolyze hippurate to release glycine and benzoic acid. The reagent ninhydrin is used to detect whether the amino acid glycine is present (ninhydrin reacts with amino acids and proteins to produce a deep blue\/purple color).<\/p>\n\n\n\n What medium is used?<\/em><\/p>\n\n\n\n The medium used in VUMIE Online for determination of hippurate hydrolysis is sodium hippurate. <\/p>\n\n\n\n How is the test performed?<\/em><\/p>\n\n\n\n A heavy inoculum from a pure overnight culture of the unknown organism is transferred by cotton-tipped applicator (swab) into the tube containing 1% sodium hippurate. After a brief incubation, ninhydrin reagent is added and a second brief incubation is performed. At the completion of the test, the tube is observed for color change indicating presence or absence of hippuricase.<\/p>\n\n\n\n What reagents are added?<\/em><\/p>\n\n\n\n Ninhydrin (consisting of 3.5 g of ninhydrin added to 50 ml of acetone and 50 ml of 1-butanol).<\/p>\n\n\n\n Performing this test in the VUMIE Online lab<\/p>\n\n\n\n Inoculation of the Medium<\/em><\/p>\n\n\n\n A fresh culture of the unknown microbe is added to the sodium hippurate tube by means of a sterile cotton-tipped applicator (swab). Forgotten how to do these things? Watch the \u201cShow Me How To\u201d videos.<\/p>\n\n\n\n This is incubated for a brief period. Then, ninhydrin reagent is added and the tube is again incubated for a brief period of time. Ninhydrin combines with amino acids and proteins to generate a deep blue\/purple color. If hippuricase is produced by the unknown microbe, the enzyme will hydrolyze hippurate to release glycine that combines with ninhydrin to produce the deep blue\/purple color. When hippurate is not hydrolyzed, there is no color change observed Complete the process of a tube-to-tube aseptic transfer to inoculate the medium. Forgotten how to do these things? Watch the \u201cShow Me How To\u201d videos.<\/p>\n\n\n\n Incubation of the Inoculated Medium<\/em><\/p>\n\n\n\n Place the inoculated tube into the 35-37 C, and it remains there for 2 hours.<\/p>\n\n\n\n After the 2 hr incubation, 2-4 drops of the ninhydrin reagent are added. The tube is then placed back into the incubator for an additional 30 minutes, after which time the tube is retrieved and the results are interpreted.<\/p>\n\n\n\n Determination of Results<\/em><\/p>\n\n\n\n Results are determined by the color of the tube following the second incubation. Positive test results appear dark blue\/purple, while negative results appear clear. Record your test result. Forgotten how to do these things? Watch the \u201cShow Me How To\u201d videos.<\/p>","protected":false},"excerpt":{"rendered":" About this test What is the purpose of this test? The purpose is to determine whether the unknown microbe produces the enzyme hippuricase, which breaks down hippurate to its components ingredients glycine and benzoic acid. How is the production of hippuricase determined? Hippuricase will hydrolyze hippurate to release glycine and benzoic acid. The reagent ninhydrin […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"doc_category":[37],"doc_tag":[],"knowledge_base":[],"class_list":["post-17823","docs","type-docs","status-publish","hentry","doc_category-biochemical-tests"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t