Labmaster Equol TR-FIA

Background

Isoflavonoids are a group of diphenolic hormone-like compounds of dietary origin that are of great interest particularly because of their anti-carcinogenic potency, but also because of their association with other Western diseases like coronary heart disease [10-12]. The isoflavonoids occur mainly in soybean products and clover seeds and leaves [13-15].

When consumed, isoflavonoids are converted by the intestinal microflora to biologically active secondary plant metabolites. Ingested glycosides are rapidly hydrolyzed by the gut bacteria, whereafter the aglycones undergo further metabolism. In this way the aglycone daidzein, which is formed from formononetin, is reduced by the intestinal microflora to the isoflavan equol (about 70 %) and O-desmethylangolensin (about 5-20 %) [1,2,3,16,17].

Equol was identified in human urine for the first time in 1982 [18,19]. Recently it was shown that equol has higher anti-carcinogenic potency, both in vitro and in vivo, than daidzein itself.

Quantitative time-resolved fluoroimmunoassay

Method

• A sample preparation by hydrolyse and ether extraction

Chart of Labmaster Equol TR-FIA method, Figure 1

• 90 minutes incubation

• Aspiration and washing

Chart of Labmaster Equol TR-FIA method, Figure 2

• 5 minutes incubation

Chart of Labmaster Equol TR-FIA method, Figure 3

• Fluorescence measurement


Ordering information

Labmaster Equol TR-FIA

For local representatives in Europe, see Ordering information.

References

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  13. Bradbury R.B. and White D.E. (Edited by Haaris R.S., Marrian G.F., and Thimann K.V.). Academic Press Inc., New York (1954) pp. 207-233.
  14. Eldridge A. and Kwolek W .F ., Journal of Agriculture and Food Chemistry 31 (1983) 394-396.
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  18. Axelson M., Kirk D.N., Farrant R.D., Cooley G., Lawson A.M. and Setchell K.D.R., Biochemical Journal 201 (1982) 353-357.
  19. Adlercreutz H., Fotsis T., Heikkinen R., Dwyer J. T., Woods M., Goldin B.R. and Gorbach S.LLancet 2 (1982) 1295-1299.