Acetyl glucoside conjugates

Daidzein-7-0-(6"-0-malonyl)glucoside Daidzein-7-0-(6"-0-acetyl)glucoside Figure 1.25 Legume isoflavone conjugates. 

Figure 4.3 Chemical structures of Isoflavone glycosides. In soy foods, Isoflavones form 7-0-P-glucosIde conjugates. A Is the simple glucoside commonly found In soy milk, B Is the 6"-0-malonyl-7-0-p-glucoslde from the soybean, and C Is the 6"-0-acetyl-7-O-p-glucoside, a product of toasting of soy flour. D is the 7-0-P-glucuronide that is the principal conjugate in the blood.

F F (95) xO B-glucoslde B-glucoside Mixture - fungal metabolites. 500 MHz NMR on mixture of Acetone isomers as acetyl derivatives. Conjugation sites determined by NMR. Anomeric H 5.57 (7.7) 5.65 (7.7)... 

According to Trautman (16), PNA was converted almost exclusively to p-nitrophenol in the mouse with 24 hours, nearly all of which was excreted in the urine as glucuronide, sulfate, glucoside, and unextractable products the mouse tissue retained only about 1% of the original dose. By comparison, the sea urchin metabolized PNA slowly p-nitrophenol and its conjugates accounted for only about 6% of the metabolites and most of the remainder (90%) was p-anisidine (p-methoxyaniline) and its N-acetyl derivative. 

It appears that glucoside isoflavones and their malonyl and acetyl conjugates are hydrolyzed by intestinal bacteria to aglycones prior to being absorbed. However, not everyone has the same intestinal microflora ability to hydrolyze the glucosides. A study (Xu et al., 1995) shows that two of six women studied were not able to hydrolyze the glucosides. Therefore, it is important to analyze the individual forms of isoflavones instead of total isoflavones in the foods, because foods vary widely in aglycone contents. 

Side chain conjugations comprise the formation of O-glycosides (glucosides and xylosides) and O-acetyl-derivatives. It is evident that these conjugates may be formed only from cytokinin derivatives bearing a hydroxyl-group in the side chain, i.e. from Z, DHZ, and OH-derivatives of BA. 

Varga, E., Malachova, A., Schwartz, H., Krska, R., Berthiller, F. (2013). Survey of deoxyni-valnol and its conjugates deoxynivalenol-3-glucoside and 3 acetyl-deoxynivalenol in 374 beer samples. Food Additives and Contaminants, 30, 137-146. 

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