Genistein determination

CHANG H 0, CHURCHWELL M I, DELCLOS K B, NEWBOLD, DOERGE D R (2000) Mass spectrometric determination of genistein tissue distribution in diet-exposed Sprague-Dawley rats. J Nutr. 130 1963-70. 

The mucosa of the GIT represents an interface between the external and internal environments. The expansive surface area is necessary for the efficient hydrolysis of foodstuffs and the absorption of energy and nutrients. The mucosa also influences the systemic availability of non-nutrient compounds in the diet, both beneficial and detrimental. Digestion and absorption of glucosinolates are critical determinants of health benefits (see Chapter 4) Similarly, the bioavailability and health benefits of phytoestrogens, such as genistein (see Chapters 5 and 10) are at least partly dependent on the carrier-mediated processes of absorption associated with the GIT (Oitate et al, 2001). Moreover, the metabolic activities of the mucosa can influence the systemic concentrations and forms of dietary phytochemicals, as exemplified by research with soy isoflavones (Andlauer et al., 2000). 

BARNES, K.A., SMITH, R.A., WILLIAMS, K., DAMANT, A.P., SHEPHERD, MJ.A., Microbore high performance liquid chromatography/electrospray ionization mass spectrometry method for the determination of the phytoestrogens genistein and daidzein in comminuted baby foods and soya flour, Rapid Comm. Mass Spectrom., 1998,12,130-138. 

Several studies have shown the ability of DNMT inhibitors to prevent cancer using different pathways [101-104]. Genistein demonstrated cancer chemopreventive activities in animal models [105]. It has been studied in different cancer cell lines and inhibition of cancer cell growth has been shown [106]. But several mechanisms, such as antihormonal effects, are discussed to explain this activity and the exact contribution of DNMT inhibition to in-vivo activity in cancer chemoprevention remains to be determined. 

Adlercreutz H, Fotsis T, Bannwart C, Wahala K, Brunow G, Hase T. 1991. Isotope dilution gas chromatographic-mass spectrometric method for the determination of lignans and isoflavonoids in human urine, including identification of genistein. Clin Chim Acta 199 263-278. 

Quercetin, a ubiquitous polyphenolic flavonoid, is one of the most potent natural antioxidants. In addition to its antioxidant properties, quercetin exhibits other activities that may enhance antineoplastic activity. As with genistein, clinical studies are yet to be performed to determine the impact of quercetin on cancer chemotherapy. 

Aussenac et al. (1998) used capillary zone electrophoresis with UV detection at 260 nm to analyze isoflavones in soybean seeds of various varieties grown in various locations. Methanol was used for extraction. Total extraction was not affected by temperature but was affected by the composition of the solvent. Electrophoresis was conducted at pH 10.5, at which the isoflavones were weak acids and were ionized. Boric acid was added to form a negatively charged borate-isoflavone complex. A fast capillary electrophoresis method was also developed by Vanttinen and Moravcova (1999) to determine daidzein and genistein after enzyme hydrolysis in soy products. Photodiode array was used to detect the isoflavones at 254 and 268 nm, respectively. Minimum detection was 0.4 mg/L. p-Nitrophenol was used as an internal standard. 

Vanttinen, K. and Moravcova, J. 1999. Phytoestrogens in soy foods determination of daidzein and genistein by capillary electrophoresis. Czech. J. Food Sci. 17 61-67. 

Together with two isoflavones, genistein (8) and prunetin (9), the relative activity of each compound was determined using the particle method. The results for the various flavones lacking B-ring substitution are... 

Tyler and coworkers (1996) observed substantial levels of genetic variation in the attraction of zoospores of different Ph. sojae genotypes to isoflavones [46]. Genetic crosses between the isolates showed that a single gene was responsible for the difference in attraction to genistein and other isoflavones [26]. The genetic differences of zoospores in response to non-isoflavone phenolics were determined by at least six additional... 

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