ISSN:
1040-0397
Keywords:
Glucosinolates
;
Sinigrin
;
Progoitrin
;
Rapeseed meal
;
Glucose oxidase
;
Tyrosinase
;
Enzyme electrode
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Sinigrin, the β-D-thioglucoside of the cruciferous plant species was hydrolyzed for 15 min at pH 7 and 30°C by the enzyme myrosinase to liberate glucose and mustard oil allylisothiocyanate as aglucone. A Clark-type pO2 sensor overlaid with a glucose oxidase + catalase membrane served for the glucose measurements, whereas the isothiocyanate component was measured (after conversion to allylthiourea) from the inhibition degree of a tyrosinase membrane/pO2 sensor. The total amounts of glucosinolates found with the glucose probe in six assorted samples of rapeseed meal and evaluated in sinigrin equivalents (13.6 -147 μmol/g) agreed with those obtained using gas chromatography as the reference. Poor agreement (results: 111.4-112.3%) was achieved when a different method of fat removal was used prior to electroanalysis. The amounts of progoitrin (not convertible to thiourea) estimated indirectly from the difference of both the glucose and the aglucone biosensor analyses were found to be in the range 6.2-103 μmol/g (44.3-83.8% of the total glucosinolates).
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/elan.1140070806
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