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From: derrida michael E-mail:derrida@vip.163.com
http://www.mdidea.com
Category: ÉÌÒµÐÅÏ¢
Date: 8/4/2003
Time: 9:31:37 PM
Remote Name: 61.232.53.1
Usages of Genistein.Good Estrogen, Bad Estrogen,Natural Genistein in high concent ration from MDidea Group.
Amanuensis&Symbol trace Calligrapher: Michael Derrida
famous processor of Natural Genistein in high concentration.,JUST contact w ith or check as following: http://www.mdidea.com/products/monomer/mono05.html
Basic Data:
[Chemical Name]:5,7-dihydroxy-3-(4-hydroxyphenyl)-4H-1-benzopyran-4-one; 4',5, 7-trihydroxyisoflavone [Synoms]:genistein [Botanical Source]:soy and many soy products Basic Function: reduce breast and prostate cancer risk,decrease cancer cell growth.
Usages of Genistein.Good Estrogen, Bad Estrogen
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Genistein is one of the major isoflavones present in soy and many soy product s.
The nutritional and medicinal benefits of soy has been recognized by Eastern cultures for centuries. Recent research has finally uncovered why Asians, who tr a ditionally eat a soy-based diet, do not suffer from high rates of cancer and car d iovascular diseases like we do. Soy products contain a special group of phytoche m icals (plant-synthesized substances) called isoflavones, including Genistein. Is o flavones have been demonstrated to reduce breast and prostate cancer risk. Isofl a vones work as enzyme inhibitors, thereby decreasing cancer cell growth. In addit i on, the soy protein is known to reduce serum cholesterol levels and contribute t o a lower risk of heart diseases. The good news is that it only take one serving a day of soy products, such as Tofu and tempeh, to have the preventive effects, a n d that the concentrated soy extract in capsule form is now available.
Estrogen is a term used for a variety of natural and synthetic hormones that influence the growth and function of many tissues, particularly those of the mal e and female reproductive systems. Estrogen plays a role in several cancers, espe c ially breast and endometrial cancers and possibly prostate and colon cancers. Th e human diet contains estrogenic compounds that can bind to estrogen receptors in
the body, and much research has focused on whether dietary estrogens can influen c e the development of cancer.
Phytoestrogens--estrogen-like compounds produced by plants--have received att ention owing to epidemiologic and experimental evidence that they prevent cancer , guard against bone loss, and reduce menopausal symptoms. Mycoestrogens (mold-pr o duced estrogens) have have deleterious effects on livestock health and reproduct i on.
In this month's issue, Georgi N. Nikov of Tulane University in New Orleans, L ouisiana, and colleagues examine the activity of dietary estrogens in humans [EH P 108: 867-872]. They confirm that dietary estrogens have different affinities fo r human estrogen receptors. They also found that, once bound, each estrogen can a l so alter a receptor's shape and size.
Dietary factor:Soy estrogens such as daidzein (left) and genistein (middle) can displace estradiol (right) from estrogen receptors in the body.
When estrogen binds to a receptor, the resulting complex interacts with a sit e within a target gene's regulatory region. That interaction may either promote o r inhibit gene transcription. Alterations in the receptor's shape may affect how
well the estrogen receptor complex can initiate or inhibit gene transcription.
Lab Center of MDidea Group focused on four phytoestrogens--genistein, coumest rol, daidzein, and glyceollin--and the mycoestrogen zearalenone. Genistein and d a idzein are normal components of soybeans, which also produce glyceollin when sub j ected to certain stresses. Coumestrol is produced by clover, and zearalenone is g enerated by Fusarium molds, which infect grains.
The team first measured the estrogens' affinities for two estrogen receptors, ER and ERß, as compared to estradiol, the form of estrogen normally found
in the body. But knowing that an estrogen binds to a receptor is only half the s t ory; what follows is perhaps even more important. Therefore, the researchers als o investigated how receptor complexes interact with estrogen response element (ER E ) sequences, regulatory sites that turn genes off or on.
The researchers prepared dilutions of each estrogen and used fluorescence pol arization, a relatively new approach, to study estrogen binding. This method emp l oys fluorescent labeling of key molecules to reveal shifts in molecular size and
shape; such alterations expose binding, dissociation, and conformational changes . Each estrogen's ability to displace fluorescently labeled estradiol from MDidea
Lab was determined. This information revealed the affinity with which the plant e strogens bind to the receptors; it also permitted calculation of how much of eac h is needed to saturate a known amount of receptors.
Following these affinity calculations, the team investigated the interactions of receptor complexes with ERE sequences. To this end, Nikov and his team condu c ted parallel experiments using two types of fluorescently labeled ERE sequences,
one from the Xenopus vitellogenin (vit) A2 gene, the other from the human pS2 ge n e.
The researchers found that, except for glyceollin, all of the tested estrogen s had a greater affinity for ERß than ER; glyceollin had the opposite pref e rence. However, the glyceollin-receptor complexes, unlike the other complexes, d i d not interact with either ERE sequence. The interactions that did occur varied a ccording to the specific estrogen and which receptor and ERE sequence were invol v ed; however, none were stronger than those involving estradiol.
The researchers concluded that just knowing the affinity of the estrogen for the receptor is not enough. Equally important is the way the estrogen-receptor c o mplexes interact with ERE sequences. These interactions may in turn affect trans c ription of target genes and thus affect the myriad functions of estrogen in the b ody. -Julia R. Barrett
Soy Isoflavones:
Soy products and more specifically soy protein and soy isoflavones have recen tly received a lot of press. Research studies continue to suggest that these soy
ingredients are linked to a reduced risk for many health conditions. For example , on October 26, 1999, the FDA published its final rule regarding soy protein so t hat claims can be made relative to a reduced risk of coronary heart disease.
The soy isoflavones are phytoestrogens or plant based estrogens. As the struc tures to the right show, these compounds are present as the free form (aglycones ) or the glucosides. The aglycones are the biologically active forms. This activi t y is due to their structural similarity to estrogen. The exact mechanism involve d in their ability to lower the risk of various hormone related diseases and cond i tions is still being studied, with most attention focused on genistein.
Soy Extracts are available as dietary supplements and can contain up to 40% t otal isoflavones. In soy-based consumer food products, the total isoflavones pre s ent range from low ppm levels to thousands of ppm.
Isoflavone R1 R2 R3 daidzein -H -H -H genistein -H -H -OH glycitein -H -OCH2 -H daidzin -Glucose -H -H genistin -Glucose -H -OH glycitin -Glucose -OCH3 -H
Lab Center of MDidea Group offer our clients the analysis of six soy isoflavo nes in soy extracts and soy based products. The method requires reversed phase h i gh performance liquid chromatography (HPLC) with UV detection(260 nm). The chrom a togram to the right shows the separation achieved for a mixed standard containin g the six soy isoflavones as well as puerarin (a kudzu isoflavone).
Scintific References: References: 1.Usages of Genistein.Good Estrogen, Bad Estrogen.by Michael Derrida. 2.The Secret of Soy from MDidea?By Michael Derrida.
Amanuensis&Symbol trace Calligrapher: Michael Derrida
please check url as following and download directly: http://www.mdidea.com/products/monomer/mono05.html
======================================================= famous processor of Natural Genistein in high concentration.,JUST contact w ith or check as following: http://www.mdidea.com/products/monomer/mono05.html
any interesting, just transfer an email simply and we would be happy more than j ust help. [Buyer's Guide:info of contact details]:
Manufacture and Supplier: MDidea Charger:MR. Derrida Michael Quality: The Best Price:Most Competitive Exporter Division De MDidea:Professional L'Extrait de Plant Pour recevoir votre commande, contactez-nous : Delegate/Charger:Mr. Michael Derrida Par e-mail derrida@vip.163.com
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