Myrosinase Activity in Armoracia Rusticana

Abstract

This work is part of a study, which is more complex regarding the activity of sinigrin-myrosinase complex. With the help of this study we are following the optimization and the characterization of myrosinase activity with the help of HPLC chromatography and the comparison of the obtained results by spectrophotometric analysis.
 At different temperatures conditions, (25°C ÷ 75°C), and reaction time (30 ÷ 390 minutes) were determined sinigrin concentration in extract (CSinExtr) and sinigrin concentration consumed in enzymatic reaction (CSinCons) by HPLC analysis. 
 The appreciation of sinigrin-myrosinase system activity was done by transforming CSinExtr and CSinCons in μg/glucose/g sample*hour.
 The best parameters, adequate to myrosinase maximum activity, in Armoracia rusticana extracts were the following: pH = 7, temperature of 55°C, and reaction time was of 210 minutes for rubbed out horseradish samples and of 240 minutes for unrubbed horseradish samples.

Horseradish (Armoracia rusticana), a neglected medical and condiment species with a relevant glucosinolate profile: a review

“…GLS concentrations in plants, although highly variable, are around 1 % of dry weight in some Brassica vegetables (Rosa et al 1997;Clarke 2010). The GLS content is higher in black mustard seed (Brassica nigra) and horseradish roots (over 10 % by dry weight) than in the other constituent parts of the Brassicaceae (Li and Kushad 2004;Mucete et al 2006). However, very little is known about the concentration and biochemical composition of horseradish, especially the distribution of GLSs in the different organs of the plants (Li and Kushad 2004).…”

“…The intense pungent aroma and the lachrymatory odour of horseradish results from crushing, grinding, or chewing the cells (Courter and Rhodes 1969;Jiang et al 2006) and therefore it is specially cultivated to supply a hot spicy flavour (Sultana et al 2003). The characteristic taste and odour is due to compounds such as GLSs and their mostly volatile breakdown products (Mucete et al 2006;Redovnikovic et al 2008a). GLSs are hydrolysed by the enzyme commonly known as myrosinase to a variety of compounds as isothiocyanates, nitriles, thiocyanates, epithionitriles, and oxazolidines.…”

“…Normally, the components that cause the intense pungency are physically separated from one another (Shehata et al 2009). GLSs are stored in the vacuole (Grob and Matile 1979;Helmlinger et al 1983;Koroleva et al 2000) while the myrosinase enzyme that causes their degradation (Mucete et al 2006) is confined within specialized cells known as myrosin cells (Kissen et al 2009;Borgen et al 2010). Upon crushing horseradish roots or leaves allyl and 2-phenylethyl isothiocyanate are produced from sinigrin and 2-phenylethyl-GLS.…”