• KOREAN JOURNAL OF CROP SCIENCE
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• v.48
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• pp.31-40
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• 2003

Phytoestrogens are oestrogenic compounds found in plants and consist of isoflavones, lignans, and coumestans. The structural similarity of phytoestrogens to endogenous oestrogens has promoted the hypothesis that phytoestrogens exert hormonal or anti-hormonal effects relevant to the risk of hormone-dependent disease and/or their suitability as a dietary alternative to hormone replacement therapy. Epidemiological studies suggest that food stuffs containing phytoestrogens may have a beneficial role in protecting against a number of chronic disease and conditions. It is thought that these estrogen-like compounds may protect against chronic diseases, such as hormone-dependent cancers, cardiovascular disease and osteoporosis. Furthermore, phytoestrogens are used as a natural alternative to hormone replacement therapy and to reduce menopausal symptoms. Phytoestrogens are considered good candidates for use in natural therapies and as chemopreventive agents in adults. However safe and efficacious levels have yet to be established.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.162-162
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• 2001

Phytoestrogens produced naturally by either plants or their seeds are three main classes of phytoestrogens: isoflavone, lignan and coumestan. Phytoestrogens can have both agonist and antagonist action of estrogenic activity. It is believed that phytoestrogens with agonist and antagonist action of estrogenic activity may reduce the risk of breast cancer, in addition to may reduce the risk of osteoporesis by therapeutic agent of breast cancer.(omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.131.1-131.1
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• 2003

Phytoestrogens are naturally occurring compounds derived from plants. Structurally, some phytoestrogens resemble endogenous estrogen of humans and animals. Phytoestrogens exhibit estrogen agonist/antagonist properties and have many biological effects such as prevention of hormone-dependent breast cancer, anti-oxidative activity, inhibition of tyrosine kinase activities and inhibition of angiogenesis. In this study we investigated whether biochanin A, a phytoestrogen, and its metabolites such genistein, p-ethylphenol and phenolic aic affect IL-4 production in EL-4 thymoma cell-line and primary lymph node cells. (omitted)

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.479-486
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• 2004

Phytoestrogens display estrogen-like activity because of their structural similarity to human estrogens and exhibit high affinity binding for the estrogen receptors (ERs). The prevalence of phytoestrogens in our diets and the biological effects that they may cause need to be fully examined. ER is the ancestral receptor from which all other steroid receptors have evolved. Although phytoestrogens serve specific signaling functions between the plants and insects, fungi, and bacteria, many chemical signals are often misinterpreted as estrogenic signals in non-target organisms such as vertebrates. There are no ERs in plants or in their most common partners, insects. However, Rhizobium soil bacteria have NodD proteins which is an intended target of phytoestrogen signaling and share genetic homology with the ER. These two evolutionarily distant receptors both recognize and respond to a shared group of chemical signals and ligands, including both agonists and antagonists. This review briefly summarizes estrogen and estrogen receptors, kinds of important phytoestrogens, their health effects as well as some of the evolutionary aspects of mechanism by which phytoestrogen mimics the endogenous ER signaling in our body.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.3
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• pp.165-169
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• 2002

We have previously demonstrated that phytoestrogens isolated from safflower seeds significantly attenuated bone loss in ovariectomized rats, and directly stimulated proliferation and differentiation of cultured osteoblastic cells. In an attempt to elucidate underlying cellular mechanisms, in the present study we investigated effects of $17{\beta}-estradiol\;(E_2)$ and phytoestrogens such as matairesinol and acacetin, a type of lignan and flavonoid, respectively, on activation of mitogen activated protein (MAP) kinases, extracellular signal-regulated kinase 1 (ERK1) and ERK2, in cultured osteoblastic ROS 17/2.8 cells. Western blot analysis with anti-MAP kinase antibody showed that a wide range concentrations $(10^{-14}\;to\;10^{-6}\;M)\;of\;E_2$ as well as both phytoestrogens induced rapid and transient activation of ERK1/2 through phosphorylation within minutes. Maximum activation of MAP kinases by $E_2$ and phytoestrogens were observed at 10 and 15 min, respectively. $E_2-induced$ phosphorylation of ERK1/2 returned to the control level at 30 min, whereas phytoestrogen-induced phosphorylation was maintained at high level until 30 min. PD-98059, a highly selective inhibitor of MAP kinase, prevented phosphorylation of ERK1/2 in the cells treated either with $E_2$ or phytoestrogens. To examine a possible involvement of estrogen receptor in the activation process of MAP kinase, Western blot analysis was performed in the presence and absence of the estrogen receptor antagonists, ICI 182,780 and tamoxifen. These antagonists blocked MAP kinase phosphorylation induced not only by $E_2,$ but also by the phytoestrogens. To the best our knowledge, this study is the first to demonstrate that phytoestrogens such as flavonoid and lignan extracted from safflower seeds produce a rapid activation of MAP kinase, at least partially via membrane estrogen receptor of the cultured osteoblastic cells.

• The Journal of Pediatrics of Korean Medicine
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• v.29 no.2
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• pp.59-77
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• 2015

Objectives Medical plant has a big role in Herbal Medicines, and most medical plant has phytoestrogens. Therefore some estrogenic effects have been reported in a lot of Korean Medicine literature. Phytoestrogens should be used carefully in children. The objective of this study is to identify reported phytoestrogenic effects in Herbal Medicines and to evaluate the characteristics of the phytoestrogens in Herbal Medicines. Methods A literature search was done with using 8 databases with a limit of reports until 12/31/2013. The estrogenic effects were summarized by each individual Korean Medicine. The frequency of the phytoestrogens was also investigated depending on the Korean medical categorization by the treatment effect. Results and Conclusions Phytoestrogenic effects were reported in 89 Herbal Medicines. Phytoestrogens were act bidirectionally, and the effect was fairly weak compared to estrogen. Phytoestrogenic effect was variable on different cells and tissues. The most frequent phytoestrogenic effect was in tonifying and replenishing medicinal, the following orders were heat-clearing, exterior-releasing, and blood-activating and stasis-dispelling medicinal. Phytoestrogens were not reported in dampness-resolving, digestant, orifice-opening, emetic medicinal.

• Journal of the Korean Wood Science and Technology
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• v.32 no.6
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• pp.1-6
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• 2004

Phytoestrogens are considered to exhibit biological activities in human and animal. There are few data on the contents of phytoestrogens in woody plants. This study was undertaken to examine phytoestrogen contents in five species (Albizzia coreana, Albizzia julibrissin, Gleditsia japonica var. koraiensis, Maackia fauriei and Sophora japonica) of leguminosae. An HPLC method was employed for the first time to analyze phytoestrogens in five species. The contents of daidzein and genistein were in the range of 2.9~170.5 ㎍/g and 1.3~118.4 ㎍/g, respectively. Daidzein and genistein were most abundantly present in the Sophora japonica among the samples examined.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3091-3096
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• 2015

Worldwide, breast cancer is the most common malignant neoplasm and the second most common cause of cancer death in women. This malignancy is recognized to be estrogen-dependent and due to this feature, hormone replacement therapy is regarded as potentially dangerous in breast cancer survivors who seek relief of their menopausal symptoms. Whereas hot flashes are detected in nearly half of postmenopausal women with a relatively high frequency and severity, botanic sources of estrogens have been proposed as an alternative treatment. Nevertheless, estrogenic properties of these compounds suggest possibility of stimulating cancer recurrence or worsening prognosis in survivors. As well, effects in improving vasomotor climacteric changes is controversial. Many studies have considered the subject, some focusing on efficacy of phytoestrogens for control of menopausal symptoms, and others discussing effects of these compounds on breast cancer outcome in terms of survival or recurrence. The present article is a concise review of the effects of consumption of phytoestrogens on menopausal symptoms, namely hot flashes, and breast cancer recurrence and mortality in survivors of the disease. Overall, the major part of the current existing literature is in favor of positive effects of phytoestrogens on breast cancer prognosis, but the efficacy on menopausal symptoms is probably minimal at the best.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.102-106
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• 2006

The phytoestrogens including isoflavones (genistein, daidzein, biochanin A, formononetin, and glycitein), coumestrol, and lignans (secoisolariciresinol, matairesinol, and anhydrosecoisolariciresinol) were quantified in edible sea vegetables from Korea. Sea vegetable samples were collected based on domestic consumption data. After hydrolysis of phytoestrogen glycosides in prepared samples, aglycones of phytoestrogens were extracted with diethyl ether and analyzed with isotope dilution gas chromatography-mass spectrometry in selected ion monitoring mode (ID-GC-MS-SIM). Total samples included 19 samples representing eight species. Most of the samples showed rather low concentrations, ranging from not determinated to $79.2\;{\mu}g/kg$ for isoflavones and from 106.4 to $694.8\;{\mu}g/kg$ for lignans. The daily intake of phytoestrogen from sea vegetables, estimated from the present data and domestic consumption data, was about $0.13\;{\mu}g/day$ for isoflavones and $2.0\;{\mu}g/day$ for lignans. When we compared these results with those from legumes, sea vegetables would not be considered the major source of phytoestrogens in the Korean diet.

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.217-220
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• 2016

Phytoestrogens are one of quasi-estrogens which are not generated within the endocrine system, but consumed by intaking phytoestrogenic plants. Phytoestrogens, also called as "dietary estrogens", are various botanic chemical compound groups naturally occurring nonsteroidal plant compounds of spontaneous generation. Due to their structural similarities to estrogone, they may provide desirable health benefits for reducing the menopausal symptoms. In this paper, various phytoestrogens were extracted from sophora root, pomegranate and kudzu by ultrasonic extraction process. In this study, the amount of extracted phytoestrogens at various ultrasonic power strengths and extraction times were compared, which could be used as basic data in the study of biology and chemistry related to natural products.