Showing papers on "Isoflavones published in 1992"
TL;DR: It is suggested that lignans and isoflavonoids may affect uptake and metabolism of sex hormones by participating in the regulation of plasma SHBG levels and in this way influence their biological activity and that they may inhibit cancer cell growth like some flavonoids by competing with estradiol for the type II estrogen binding sites.
451 citations
01 Jan 1992
TL;DR: Among the almost unlimited number of plant secondary constituents, isoflavonoids are especially suitable to demonstrate physiological functions and ecological roles for such compounds in the producing plant, as a consequence of their bioactive properties.
Abstract: Among the almost unlimited number of plant secondary constituents, isoflavonoids are especially suitable to demonstrate physiological functions and ecological roles for such compounds in the producing plant Isoflavonoids (ie, isoflavones, isoflavanones, isoflavans, pterocarpans, coumestans, rotenoids) are characteristic constituents of the Leguminosae and they are known to be involved in the interaction of the individual plant species with other organisms Furthermore, they provide plants with a means of adjustment to changing circumstances such as microbial infection These functions are a consequence of their bioactive properties which may be antibiotics, repellents, attractants or signal compounds1-4
76 citations
TL;DR: Pulse-labeling experiments of white lupin (Lupinus albus L.) cell cultures with [U-(14)C]l-phenylalanine for 72 h resulted in the incorporation of the radioactivity into the isoflavone aglucones, glucosides, and prenylated derivatives.
Abstract: Pulse-labeling experiments of white lupin (Lupinus albus L.) cell cultures with [U-14C]l-phenylalanine for 72 h resulted in the incorporation of the radioactivity into the isoflavone aglucones, glucosides, and prenylated derivatives. Both the aglucones genistein and 2′-hydroxygenistein and their 7-O-glucosides accounted for 85% of the total isoflavonoids identified in the cultured cells and contained 35% of the radioactivity, whereas the prenylated derivatives comprised 15 and 65%, respectively. Almost 20% of the labeled isoflavones of the cellular pool was recovered from the culture medium, 90% of which were monoprenylated and diprenylated derivatives containing 80% of the radioactivity. These results clearly demonstrate the release into the culture medium of a substantial amount of the endogenously synthesized isoflavonoids, especially the prenylated derivatives.
23 citations
TL;DR: The results suggest that the isoflavones inhibited the activation of PLC at the G-protein or downstream of the sequences in signal transduction as well as the catalytic activity of phospholipase-C in 3T3 cell extracts was not inhibited by these is oflavones.
Abstract: The effect of isoflavone compounds, genistein and daidzein, on the breakdown of inositol phospholipids in 3T3 cells was studies. Genistein (100μg/ml) inhibited the sitmulation of the production of inositol phosphates by bombesin. The stimulated production of inositol phosphates by AlF-4 was also inhibited by genistein (IC50=0.6μg/ml)and daidzein (IC =2μg/ml). However, the catalytic activity of phospholipase-C (PLC) in 3T3 cell extracts was not inhibited by these isoflavones. These results suggest that the isoflavones inhibited the activation of PLC at the G-protein or downstream of the sequences in signal transduction.In permeabilized 3T3 cells, the inhibition of AlF-4 plus adenosine triphosphate (ATP)-dependent PLC was recovered by increasing ATP but not AlF-4. Genistein also inhibited the activity of adenosin 5'-[3-O-thiotriphosphate](ATP[S])-dependent PLC. The effect of genistein and other inhibitors of protein tryrosine kinases and phosphatases suggests that protein tyrosine phosphorylation is not involved in the activation of PLC in 3T3 cells and that AlF-4-and ATP[S]-mediated activation of PLC involves a different mechanism from the tyrosine kinase-mediated activtion of PLC.Daidzein and genistein seem to interrupt the ATP-dependent step of PLC activation by a putative G-protein.
19 citations
TL;DR: The chloride content of Lupin Seedings Treated with Copper Chloride acts as a “spatially aggregating agent” to increase theIsoflavones in the substance and increase the likelihood of its synthesis inducers.
Abstract: (1992). Accumulation of Isoflavones in Lupin Seedings Treated with Copper Chloride. Bioscience, Biotechnology, and Biochemistry: Vol. 56, No. 4, pp. 690-691.
16 citations
01 Jan 1992
16 citations
TL;DR: 2′-hydroxygenistein was the most potent inhibitor of the enzymatic activity of acidic cell wall isoperoxidases from lupin hypocotyls and was discussed on the basis of the compartimentalization of auxin catabolism in both young epidermal cells and differentiating vascular tissues of l upin seedlings.
15 citations
TL;DR: Phenylation of 3-phenylsulfonlylchroman-4-ones using Ph3BiCO3 leading to the synthesis of isoflavanones and isoflavones is reported as mentioned in this paper.
Abstract: Phenylation of 3-phenylsulfonlylchroman-4-ones using Ph3BiCO3leading to the synthesis of isoflavanones and isoflavones is reported.
10 citations
TL;DR: In this paper, the chloroform extract of the roots of Milletia auriculata has yielded three prenylated isoflavones in addition to the previously reported is oflavones isoauriculatin, auriculin, millettin, and scandenone and the rotenoid sumatrol.
8 citations
TL;DR: One-step chemical conversion of flavanones into isoflavones by use of thallium trinitrate (TIN) is reported in this paper, and the mechanism of a 2,3-aryl migration in this reaction is discussed in relation to in vivo rearrangement process of precursors in the is oflavone biosynthesis.
Abstract: One-step chemical conversion of flavanones into isoflavones by use of thallium trinitrate (TIN) is reported, and the mechanism of a 2,3-aryl migration in this reaction is discussed in relation to in vivo rearrangement process of flavanone precursors in the isoflavone biosynthesis.
3 citations
TL;DR: Phenylation of 3-phenylsulfonlylchroman-4-ones using Ph3BiCO3 leading to the synthesis of isoflavanones and isoflavones is reported as discussed by the authors.
Abstract: Phenylation of 3-phenylsulfonlylchroman-4-ones using Ph3BiCO3leading to the synthesis of isoflavanones and isoflavones is reported.