:Sakaguchi test

{{Short description|Chemical test used to detect presence of arginine in proteins}}

File:Sakaguchi reaction-en.svg

The Sakaguchi test is a chemical test used to detect presence of arginine in proteins. It is named after the Japanese food scientist and organic chemist, Shoyo Sakaguchi (1900–1995) who described the test in 1925.{{cite journal |last=Sakaguchi |first=Shoyo |date=April 1925 |title=Über eine neue Farbenreaktion von protein und arginin |trans-title=About a new colorimetric reaction of protein and arginine |url=https://academic.oup.com/jb/article-abstract/5/1/25/2183654 |journal=Journal of Biochemistry |language=de |publisher=Oxford University Press; Japanese Biochemical Society |volume=5 |pages=25–31 |doi=10.1093/oxfordjournals.jbchem.a128359}} The Sakaguchi reagent used in the test consists of 1-Naphthol and a drop of sodium hypobromite. The guanidino (–C group in arginine reacts with the Sakaguchi reagent to form a red-coloured complex.{{cite book|author=Chatterjea|title=Textbook of Biochemistry for Dental/Nursing/Pharmacy Students|url=https://books.google.com/books?id=xN0YYypnZVkC&pg=PA51|date=1 January 2004|publisher=Jaypee Brothers Publishers|isbn=978-81-8061-204-6|page=51}}{{cite book|author=R.A. Joshi|title=Question Bank of Biochemistry|url=https://books.google.com/books?id=Acf9BkEqJWYC&pg=PA64|year=2006|publisher=New Age International|isbn=978-81-224-1736-4|page=64}}{{cite book|author=Dandekar|title=Practicals And Viva In Medical Biochemistry|url=https://books.google.com/books?id=s9HEoJquruwC&pg=PA28|date=1 January 2004|publisher=Elsevier India|isbn=978-81-8147-025-6|page=28}}{{Cite book |last1=Joshi |first1=Rashmi A. |url=https://books.google.com/books?id=avDlDrPR4joC&dq=The+guanidine+group+in+arginine+reacts+with+the+Sakaguchi+reagent+to+form+a+red-coloured+complex&pg=PA74 |title=Guide to Bio-chemistry |last2=Marks |first2=Victor |date=30 June 2004 |publisher=B. Jain Publishers |isbn=9788180560538 |page=74 |language=en}}