Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9602659 | Enzyme and Microbial Technology | 2005 | 5 Pages |
Abstract
A comparison of the spectrophotometric detection and quantification of a number of 4-substituted phenols by two sources of the enzyme tyrosinase (Agaricus bisporus (mushroom) versus Pseudomonas putida) is described. Incubation of either source of tyrosinase with selected 4-substituted phenols results in the formation of coloured products that absorb light maximally within a narrow wavelength range (400-423 nm). The inclusion of the nucleophile 3-methyl-2-benzothiazolinone (MBTH) in the tyrosinase assay results in more intensely coloured products that also absorb light within a narrow wavelength range (440-475 nm). The molar extinction coefficient of the reaction products in the tyrosinase and tyrosinase-MBTH assay differed dramatically with values between 714-1580 and 14213-26563 Mâ1 cmâ1, respectively. The addition of MBTH improved the sensitivity of the reaction between 1.3- and 100-fold, depending on the substrate and source of the enzyme. The limit of detection of 4-substituted phenols also varied according to substrate and the source of enzyme used in the assay. The lowest detectable concentration of 4-substituted phenol was 2.5 μM 4-hydroxyphenoxy acetic acid in the presence of mushroom tyrosinase and MBTH and 2.5 μM 2-(4-hydroxyphenyl) ethanol in the presence of cell extract of P. putida F6 and MBTH.
Keywords
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Bioengineering
Authors
Aoife M. McMahon, Evelyn M. Doyle, Kevin E. O'Connor,