Isoflavones distribution

While fiavonoids have the 2-phenylchromen-4-one backbone, isoflavonoids (Fig. 8) have the 3-phenylchromen-4-one backbone, with no hydroxyl substitution at position 2 in the case of isofiavones. In contrast with the parent class of fiavonoids, the distribution of the isoflavonoid class in the plant kingdom is relatively limited, probably owing to the sporadic occurrence of isoflavone synthase. Isoflavonoids... 

However, studies in hypercholesterolemic subjects, using soy protein depleted of isoflavones have shown that soy protein independently of isoflavones can favorably affect LDL size, LDL particle distribution was shifted to a less atherogenic pattern,and can decrease triglyceride concentrations, triglyceride fatty acid fractional synthesis rate, and cholesterol... 

The flavonoids, derivatives of flavone (353) and of isoflavone (354), are widely distributed among plants of many kinds. They provide colour (from pale yellow to orange) in flowers and their potential as dyes is being revived now that awareness of the toxicity of some synthetic dyes is increasing, for example morin (355 CI. Natural Red) is one of many... 

The basis for understanding the health benefits of isoflavones requires detailed knowledge on the absorption, distribution, metabolism, elimination, and bioavailability of these phytoestrogens that demands robust, precise, accurate, and affordable analyses from biological and other matrices. 

Flavonoids are ubiquitous in all terrestrial plants (except the Anthoceropsidae) but the distribution of isoflavonoids among plants is relatively sparse, probably owing to the sporadic occurrence of the enzyme isoflavone synthasa that stabilises, by an aryl migration, the isoflavonoid skeleton. Accordingly, most of the isoflavonoids have been isolated from leguminous plants [3]. 

Isoflavones of phy to estrogens such as daidzein (27), genistein (28), and glycitein (29) are widely distributed in the natural kingdom. The glucoside... 

Another basic difference between the two materials is that Oasis HLB is macroporous (80 A pores) while LiChrolut EN and Isolut ENV+ are basically nanoporous materials with the maximum pore size distribution located at 20—30 A. For this reason, the latter sorbents perform much better in extracting smaller molecules with molecular masses less than 500 Da, as is the case with the above halogenated acetic acid derivatives [326, 327] or aryl sulfonates [328]. On the contrary, macroporous Oasis HLB is the material of choice when larger analytes are the target of pre-concentration procedures, as was the case with tetracycline and macroHde antibiotics [321-324]. Another vivid example of this kind is pre-concentration of soy isoflavones [331], where Oasis HLB and macroporous Strata X display by far higher recovery values. On the other hand, the size exclusion effect can be exploited purposefully when only smaller molecules have to be retained with the elimination of the major sample matrix. The best example of this type of applications is the analysis of drugs and drug metaboHtes in whole blood or blood plasma [273-275]. Here the microporous hypercrosslinked polystyrene Purosep-270 is the best possible SPE material since it functions as an RAM. 

These results (Fig. 8.3) may be compared with those shown in Wang et al. who describe analysis of the agronomic characteristics of 210 soybean cultivars grown in the State of South Dakota in the United States and conclude that the isoflavone content and the distribution of the different aglycones in non-transgenic... 

The Role of Flavonoids in Pollination and Propagule Dispersal Mechanisms Isoflavones Biosynthesis Distribution Biological Properties Derivatives of Isoflavones Coumestans... 

---