Methods for the assay of amino acids and peptides are most important in elucidating the structure of proteins and peptides. In many important areas of research such as in endocrinology, neurobiology, and genetics, methods are needed with sens itivity higher than is avai lable with the widely used colorimetric ninhydrin procedure. A short whi le ago, we noted that all primary amines react with n...

Sensitive and selective, but fast and simple assays of cyanide ion in waste and natural waters, as well as in biological samples are required in case of accidental pollution with such species. Cyanide reaction with ninhydrin has been recommended for instant detection of small traces of cyanide (detection limit 1.5 ng ml-1). However, the oxidizers and heavy metal ions, such as Hg, Cu, Ag may int...

J. Inst. Brew. 115(2), 122–127, 2009 In this study we present a ninhydrin based microwell assay that can be utilized in place of the traditional Kjeldahl method for the determination of the protein content of beer or wine. In addition, the assay is ideal for the determination of free amino acids in beer (FAN), a term understood and used by brewers, and yeast assimilable nitrogen (YAN) used by e...

A peptide was obtained from culture filtrates of a bacterium which was newly isolated and tentatively named Bacillus cereus SW. The peptide was composed of Asx, Ser, Glx, Leu, Tyr, Pro, and an unknown amino acid in a ratio of 2:1:1:1:1:1:1, but, unless hydrolyzed with HCI, it was ninhydrin reaction negative. The peptide effectively inhibited the growth of all fungi and yeasts so far examined, w...

Ninhydrin (2,2-dihydroxy-1,3-indanedione or 1,2,3-triketo-hydrindene hydrate) is a chemical used in the detection of free amino and carboxyl groups in proteins and peptides. Allergic, immunoglobulin E (IgE)-mediated rhinitis caused by ninhydrin was diagnosed earlier in a 41 yr old woman working as a laboratory technician in a forensic laboratory. Despite handling ninhydrin only in a flow cabine...