Horseradish Extract Research Articles

Determination of isothiocyanates and related compounds in mustard extract and horseradish extract used as natural food additives

Amounts of isothiocyanates and related compounds in a mustard extract and a horseradish extract for food additive use were determined by GC, after confirmation of the identity of GC peaks by GC/MS. Amounts of allyl isothiocyanate, which included that of allyl thiocyanate, because most of the allyl thiocyanate detected in the sample was assumed to have been formed from allyl isothiocyanate during GC analysis, were 97.6% and 85.4%, in the mustard extract and the horseradish extract, respectively. Total amounts of the identified isothiocyanates in the mustard extract and the horseradish extract were 98.5% and 95.4%, respectively. Allyl cyanide, a degradation product of allyl isothiocyanate, was found in the mustard extract and the horseradish extract at the levels of 0.57% and 1.73%, respectively. beta-Phenylethyl cyanide, a possible degradation product of beta-phenylethyl isothiocyanate, and allyl sulfides were found in the horseradish extract, at the levels of 0.13% and 0.46%, respectively. Allylamine, which is another degradation product of allyl isothiocyanate, was determined after acetylation, and was found in the mustard extract and the horseradish extract at the levels of 8 micrograms/g and 67 micrograms/g, respectively.

The Development of a Phytoremediation Technique for the Detoxification of Soils Contaminated with Phenolic Compounds Using Horseradish Peroxidase (Armoracia rusticana): Preliminary Results

ABSTRACT The proposed phytoremediation technique is based on the successful exploitation and optimization of oxidative coupling, mediated by horseradish peroxidase. Susceptibility to degradation of a selection of phenolic compounds, in solution, by horseradish peroxidase appears to be structurally related and was found to be of the order 2,4-dichlorophenol (2,4-DCP) > 4-chlorophenol (4-CP) > 2-chlorophenol (2-CP). Only 1.89% of 2,4-DCP, at an initial concentration of 5 mM, remained unchanged at the end of the experiment. Reaction rates between purified horseradish peroxidase and 2,4-DCP were found to be extremely rapid with 74% of the substrate removed from solution during the first 30 s. Inhibition of the reaction by the heavy metals Cd, Zn, Ni, and Pb at concentrations of 100 mg/l is of concern because these metals are often present in contaminated soils. H2O2 has a dominant role in optimizing peroxidase activity in crude horseradish extracts. Fluctuations in temperature and pH, normally experienced in soils, did not appear to have a detrimental impact on peroxidase activity. However, the functioning of the enzyme is seriously affected at a pH ≤ 3. All reactions in this study were carried out in solution.

Oscillations in peroxidase-catalyzed reactions and their potential function in vivo

The peroxidase-oxidase reaction has become a model system for the study of oscillations and complex dynamics in biochemical systems. In the present paper we give an overview of previous experimental and theoretical studies of the peroxidase-oxidase reaction. Recent in vitro experiments have raised the question whether the reaction also exhibits oscillations and complex dynamics in vivo. To investigate this possibility further we have undertaken new experimental studies of the reaction, using horseradish extracts and phenols which are widely distributed in plants. The results are discussed in light of the occurrence and a possible functional role of oscillations and complex dynamics of the peroxidase-oxidase reaction in vivo.

Conditions for the Adsorption of Proteins on Ultrastable Zeolite Y and Its Use in Protein Purification

The adsorption of proteins on ultrastable zeolites was investigated. Protein binding to one of these, ultrastable zeolite Y (USY), was studied in detail. Protein binding to USY, with a Si/Al ratio of >240, was found to be dependent on the pH of the solution, being highest at or just below the pIof the protein. The amount of protein adsorbed on the zeolite was found to be 10 times as much as the estimated binding to the external surface of the USY. We propose an adsorption mechanism involving the formation of a protein layer strongly bound to the USY surface, further protein layers being formed on top of this on the basis of protein–protein interactions. The protein–protein interactions can be disrupted by changing the pH. Ultrastable zeolite Y was used as a new matrix for protein purification. Undesired proteins can be removed from a crude preparation by adsorption on USY, increasing the purity of a specific protein, or the protein can be adsorbed on the zeolite and subsequently eluted through changing the pH. These two means of protein purification are exemplified by the purification of peroxidase from a crude horseradish extract and by the purification of lysozyme from egg white.

Allyl thiocyanate — Natural product or artifact in Crucifer extracts?

Allyl thiocyanate and isothiocyanate were synthesized and could be analysed by gas chromatography without isomerization by keeping the injector at, or below, 50°C. Synthetic allyl isothiocyanate contained none of the isomeric thiocyanate but allyl thiocyanate contained 0.5% of isothiocyanate. The NMR spectra indicated both compounds to be free of the corresponding isomer. Analysis of extracts of stinkweed, mustard and horseradish by GC using non-isomerizing conditions showed that only the stinkweed extract contained allyl thiocyanate. Mustard and horseradish extracts contained allyl, and other, isothiocyanates but no allyl thiocyanate. Allyl thiocyanate previously reported in extracts of mustard and horseradish was most likely an artifact caused by partial isomerization of allyl isothiocyanate under the conditions of isolation and/or analysis.

The role of sulphur compounds in evaluation of flavouring value of some plant raw materials

The aim of the study was to determine the composition of flavour isolates from garlic and horse-radish, prepared by dichlorodifluoromethane extraction. Gas chromatography, with olfactory determination of the flavour of the resolved components, and gas chromatography combined with mass spectrometry were used. In the garlic extract 19 components comprising mono-, di-, and trisulphides and thiophene derivatives were detected. In the horse-radish extract 14 components including isothiocyanates, thiocyanates and cyanides were identified.

Role of bacteria in the oxidation of myoglobin.

The addition to steaks of cell suspensions of a number of aerobic bacteria and of Saccharomyces cerevisiae greatly increased the rate of discoloration. Low inocula resulted in the more rapid appearance of the brown color of metmyoglobin, whereas high cell populations quickly produced the purple color of myoglobin. Sonically treated suspensions of Pseudomonas geniculata produced similar changes in surface color but less rapidly. No such effect was observed with Lactobacillus plantarum.The visible changes in color were found to be associated with the oxygen demand of the surface tissue including, of course, the demand of any contaminating microorganisms. Inhibitors of respiratory activity inhibited the rate of discoloration under normal atmospheric conditions. However, when the oxygen level in the atmosphere was reduced, the inhibitors had no significant effect. In an oxygen-free atmosphere, the steak surfaces were the purple color of myoglobin; at 10 mm oxygen pressure, the pigment was oxidized to metmyoglobin and the surface was brown in color. No bacterial activity was necessary for pigment oxidation under low oxygen pressures. Addition of dilute solutions of glucose oxidase resulted in rapid oxidation of the meat pigment to metmyoglobin both in extracts and on steak surfaces. More concentrated solutions resulted in further oxidation as evidenced by the appearance of a green color. Horseradish extract with a high peroxidase activity added with H(2)O(2) resulted in rapid oxidation of the pigment but neither were very effective alone, although H(2)O(2) did result in a browning reaction in aged steaks. It is concluded that the primary role of the bacteria in meat discoloration is in the reduction of the oxygen tension in the surface tissue. The implications of the data are discussed and a possible mechanism of myoglobin oxidation is proposed.

Role of Bacteria in the Oxidation of Myoglobin12

The addition to steaks of cell suspensions of a number of aerobic bacteria and of Saccharomyces cerevisiae greatly increased the rate of discoloration. Low inocula resulted in the more rapid appearance of the brown color of metmyoglobin, whereas high cell populations quickly produced the purple color of myoglobin. Sonically treated suspensions of Pseudomonas geniculata produced similar changes in surface color but less rapidly. No such effect was observed with Lactobacillus plantarum.The visible changes in color were found to be associated with the oxygen demand of the surface tissue including, of course, the demand of any contaminating microorganisms. Inhibitors of respiratory activity inhibited the rate of discoloration under normal atmospheric conditions. However, when the oxygen level in the atmosphere was reduced, the inhibitors had no significant effect. In an oxygen-free atmosphere, the steak surfaces were the purple color of myoglobin; at 10 mm oxygen pressure, the pigment was oxidized to metmyoglobin and the surface was brown in color. No bacterial activity was necessary for pigment oxidation under low oxygen pressures. Addition of dilute solutions of glucose oxidase resulted in rapid oxidation of the meat pigment to metmyoglobin both in extracts and on steak surfaces. More concentrated solutions resulted in further oxidation as evidenced by the appearance of a green color. Horseradish extract with a high peroxidase activity added with H(2)O(2) resulted in rapid oxidation of the pigment but neither were very effective alone, although H(2)O(2) did result in a browning reaction in aged steaks. It is concluded that the primary role of the bacteria in meat discoloration is in the reduction of the oxygen tension in the surface tissue. The implications of the data are discussed and a possible mechanism of myoglobin oxidation is proposed.