Fortschrittsbericht Zur alimentären Aufnahme, Analytik und biologischen Bedeutung des Thiocyanats

Abstract

A survey is given of the alimentary ingestion, metabolization and elimination as well as of the biological significance of thiocyanate (SCN-) in the mammalian organism. SCN- is an important nutritional factor since it influences essential bodily functions, e.g. immune response. Its analytical determination in vegetable and animal foodstuffs may be considerably affected by the reversible binding of SCN- to protein molecules and by natural products, e.g. amino acids and cyanide, from glycosidic precursors, which interfere with the reaction with bromine. This will be combining paper chromatography with gas chromatography. Except Brassica species which are relatively high in SCN- in glycosidic combination, vegetable foodstuffs contain nearly 0.1-1.3 mg SCN-/kg fresh material; animal foodstuffs, e.g. beef, contains 0.5-0.7 mg SCN-/kg. Balances calculations have shown that in non-smokers the average alimentary ingestion ranges from 1.8 to 5.2 mg SCN-/d.

Biological Chemistry of Hydrogen Selenide

“…Given the mechanism by which rhodanase operates (reaction of Cys-247 with S 2 O 3 2− to produce a persulfide, CySSH, followed by reaction with CN − to regenerate Cys-247 and produce SCN − ) [154,155], and given the higher reactivity of Se, we imagine that species like GSSeH (Equation (7)) may react with CN − in vivo to produce SeCN − [156]. There are many endogenous and exogenous sources of CN − , including the metabolism of vitamin B 12 and certain foods containing cyanogenic glucosides, for example, nuts (especially almonds) and cruciferous vegetables (e.g., the Brassica) [157]. Nonmetabolic sources of cyanide in humans include tobacco and occupationally derived smoke (HCN, e.g., >200 mg/cigarette) [158], chlorination of glycine by human myeloperoxidase (MPO) during inflammation [159], and cyanogenesis (the biochemical production of CN − ) by Pseudomonas aeruginosa (an opportunistic pathogen that infects wounds and the lungs of immune-compromised individuals) [160,161,162,163,164].…”

Synergistic effect of bimetallic Ag@Cu nanorods modified electrode for enhanced electrochemical sensing of thiocyanate ions

“…It is a normal constituent in human saliva, urine, and serum, which is introduced through vegetables, including cabbage and cauliflower and as a drug for thyroid treatment and arterial hypertension [4][5][6][7][8][9]. The concentration of SCN -depends upon the nature of food habits and is between 0.5 and 2 mM with an average level of 1 mM [10].…”

Optimizing the Electrocatalytic Activity of Surface Confined Co Macrocyclics for the Electrooxidation of Thiocyanate at pH 4

“…It is analogous to the cyanate ion (OCN À ) and is one of the pseudo-halides, due to the similarity of its reactivity to that of halide ions. The detection of thiocyanate is important since it is present in human body fluids at low levels as a result of the ingestion of foods that contain thiocyanate like milk and cheese [1], vegetables such as cabbage, kale, turnip [2], and also as a result of tobacco smoking [3][4][5]. In fact, the presence of thiocyanate in saliva can be used to discriminate between smokers and non-smokers [5,6].…”