Two variants of immunoassay for the determination of biochanin A (5,7-dihydroxy 4'-methoxy isoflavone), i.e., a radioimmunoassay (RIA) and an indirect ELISA, have been developed and evaluated. Both methods employ the same rabbit antiserum to a 7-O-carboxymethyl-5-hydroxy-4'-methoxyisoflavone-bovine serum albumin (BSA) conjugate. A 125I-labeled hapten-tyrosine methyl ester (TME) conjugate was used as a radioligand for the RIA. The indirect ELISA uses immunogen-coated microtitration plates and a peroxidase-labeled antirabbit Ig antibody. Both methods are specific for biochanin A with a comparable sensitivity (3.1 pg/tube for RIA; 5.3 pg/well for ELISA); however, their sensitivity to individual cross-reactants differs. The main cross-reactants are sissotrin (the cross-reactivity 15.7% for RIA; 120% for ELISA), 5-hydroxy, 4',7-dimethoxy isoflavone (51.5% for RIA; 46.5% for ELISA), prunetin (4.5% for RIA; 5.0% for ELISA), genistein (0.8% for RIA; 2.8% for ELISA) and formononetin (0.4% for RIA; 0.3% for ELISA). These methods were used for the analysis of biochanin A in alfalfa and in several nonleguminous plants.

• MeSH
• antisérum chemie   imunologie   MeSH
• ELISA metody   MeSH
• genistein analýza   chemie   imunologie   MeSH
• hapteny analýza   chemie   imunologie   MeSH
• imunoglobulin G chemie   imunologie   MeSH
• isoflavony analýza   imunologie   MeSH
• králíci MeSH
• Medicago sativa chemie   MeSH
• peroxidasa chemie   MeSH
• radioimunoanalýza metody   MeSH
• senzitivita a specificita MeSH
• sérový albumin hovězí chemie   imunologie   MeSH
• skot MeSH
• specificita protilátek imunologie   MeSH
• zkřížené reakce imunologie   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antisérum MeSH
• biochanin A MeSH Prohlížeč
• genistein MeSH
• hapteny MeSH
• imunoglobulin G MeSH
• isoflavony MeSH
• peroxidasa MeSH
• sérový albumin hovězí MeSH

Both bifidobacteria and clostridia are part of the natural gut microflora and while clostridia may be responsible for severe intestinal infections, bifidobacteria are probiotic microorganisms belonging to the most important prospective bacteria in the bowel. The antimicrobial activity of biochanin A was tested in vitro against six Bifidobacterium spp., and eight Clostridium spp. using the broth microdilution method. Biochanin A showed an inhibition against all clostridia in the range of minimum inhibitory concentrations (MIC) from 64 microg/mL (for Cl. clostridioforme, strains DSM 933 and I3) to 1,024 microg/mL (for Cl. perfringens, DSM 11778). No bifidobacteria were suppressed at four-fold higher concentration (MICs > 4,096) than MIC of Cl. perfringens. These results indicate selective growth inhibition of biochanin A and its potential use in antimicrobial prevention and/or protection.

• MeSH
• antibakteriální látky farmakologie   MeSH
• Bifidobacterium klasifikace   účinky léků   růst a vývoj   MeSH
• Clostridium klasifikace   účinky léků   růst a vývoj   MeSH
• druhová specificita MeSH
• genistein farmakologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• střeva mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antibakteriální látky MeSH
• biochanin A MeSH Prohlížeč
• genistein MeSH

The dietary intake of flavonoids seems to be inversely related to cardiovascular mortality. The consumption of isoflavonoids is increasing in the general population, especially due to the use of food supplements and a variety of isoflavonoid-rich foods. However, detailed studies on the vascular influence of individual pure isoflavonoids are mostly missing. For this study, 16 isoflavonoids were initially screened for their vasorelaxant properties on rat aortas. The 2 most potent of them, biochanin A and glycitein, were further tested for the mechanism of action on porcine coronary arteries. They both induced an endothelium independent vascular relaxation, with EC50 below 6 and 17 µM, respectively. Biochanin A, but not glycitein, was able to block the vasoconstriction caused by KCl, CaCl2, serotonin, and U46619 in a dose-dependent manner. Another series of experiments suggested that the major mechanism of action of biochanin A was the inhibition of L-type calcium channels. Moreover, biochanin A in relatively small concentrations (2 - 4 µM) interfered with the cGMP, but not cAMP, pathway in isolated coronary arteries. These results indicate that some isoflavonoids, in particular biochanin A, are able to have vasodilatory effects in micromolar concentrations, which is of potential clinical interest for the management of cardiovascular pathologies.

• MeSH
• cévní endotel MeSH
• genistein MeSH
• isoflavony * MeSH
• koronární cévy MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• prasata MeSH
• vápník MeSH
• vápníkové kanály * MeSH
• vazodilatace MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biochanin A MeSH Prohlížeč
• genistein MeSH
• isoflavony * MeSH
• vápník MeSH
• vápníkové kanály * MeSH

Phytoestrogens are naturally occurring nonsteroidal phenolic plant compounds that, due to their molecular structure and size, resemble vertebrate steroids estrogens. This review is focused on plant flavonoids isoflavones, which are ranked among the most estrogenic compounds. The main dietary sources of isoflavones for humans are soybean and soybean products, which contain mainly daidzein and genistein. When they are consumed, they exert estrogenic and/or antiestrogenic effects. Isoflavones are considered chemoprotective and can be used as an alternative therapy for a wide range of hormonal disorders, including several cancer types, namely breast cancer and prostate cancer, cardiovascular diseases, osteoporosis, or menopausal symptoms. On the other hand, isoflavones may also be considered endocrine disruptors with possible negative influences on the state of health in a certain part of the population or on the environment. This review deals with isoflavone classification, structure, and occurrence, with their metabolism, biological, and health effects in humans and animals, and with their utilization and potential risks.

• Klíčová slova
• biochanin A, daidzein, equol, formononetin, genistein, glycitein, isoflavones, phytoestrogens,
• MeSH
• equol chemie   klasifikace   metabolismus   MeSH
• fytoestrogeny chemie   klasifikace   metabolismus   MeSH
• genistein chemie   klasifikace   metabolismus   MeSH
• isoflavony chemie   klasifikace   metabolismus   MeSH
• lidé MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• biochanin A MeSH Prohlížeč
• daidzein MeSH Prohlížeč
• equol MeSH
• formononetin MeSH Prohlížeč
• fytoestrogeny MeSH
• genistein MeSH
• glycitein MeSH Prohlížeč
• isoflavony MeSH

The isoflavonoids, genistein (4',5,7-trihydroxyisoflavone), biochanin A (5,7-dihydroxy-4'-methoxyisoflavone), daidzein (4',7-dihydroxyisoflavone), and formononetin (7-hydroxy-4'-methoxyisoflavone) are supposed to be health-promoting dietary factors of plant origin. They are particularly abundant in seeds and other parts of many plant species belonging to Leguminosae. The most popular source of isoflavonoids in human diet is soy. Here, evidence is presented that isoflavonoids are regularly found in beer. Diethyl ether extracts of beer were fractionated on thin-layer chromatography-silica, (straight phase) and rechromatographed using a reversed phase high-performance liquid chromatography octadecylsilica column. The fractions were analyzed by two recently developed radioimmunoassays, the first of them being specific for diadzein/formononetin and the second one specific for genistein/biochanin A. The immunoreactivity was found only in fractions with the mobility corresponding to the positions of standards on control chromatograms. Additionally, 26 samples of bottled beer were analyzed for isoflavonoid content using the combination of reversed phase high-performance liquid chromatography and radioimmunoassay. The sum of the four isoflavonoids ranged from 1.26 to 29 nmol/L in individual beers. Formononetin was the major isoflavonoid (0.19-14.99 nmol/L), whereas the concentration of daidzein was several times lower (0.08-2.5 nmol/L). Genistein and biochanin A concentrations were comparable, ranging from 0.169-6.74 nmol/L and from 0.820-4.84 nmol/L for genistein and biochanin A, respectively. It is concluded that beer contains significant amounts of biologically active isoflavonoid phytoestrogens.

• MeSH
• genistein analýza   MeSH
• isoflavony analýza   MeSH
• pivo analýza   MeSH
• radioimunoanalýza MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, P.H.S. MeSH
• Názvy látek
• biochanin A MeSH Prohlížeč
• daidzein MeSH Prohlížeč
• formononetin MeSH Prohlížeč
• genistein MeSH
• isoflavony MeSH

UNLABELLED: In this study, we tested 15 naturally occurring isoflavones and their metabolites for their possible antibacterial properties against nine Gram-positive and Gram-negative bacteria. The in vitro antibacterial activity was determined using the broth microdilution method, and the results were expressed as minimum inhibitory concentrations (MICs). 6,7,4'-trihydroxyisoflavone (demethyltexasin), 7,3',4'-trihydroxyisoflavone (hydroxydaidzein), 5,7-dihydroxy-4'-methoxyisoflavone (biochanin A), 7,8,4'-trihydroxyisoflavone (demethylretusin) and 5,7,4'-trihydroxyisoflavone (genistein) produced significant antibacterial activity (MICs ≥ 16 μg ml(-1)). The most effective compound, demethyltexasin, was subsequently tested for its growth-inhibitory effect against Staphylococcus aureus, and it exhibited significant antistaphylococcal effects against various standard strains and clinical isolates, including methicillin and tetracycline resistant ones with the MICs ranging from 16 to 128 μg ml(-1). SIGNIFICANCE AND IMPACT OF THE STUDY: The results of the structure-activity relationship (SAR) analysis identified ortho-dihydroxyisoflavones as a class of antibacterially effective compounds emphasizing the hydroxyl groups at C-5, 6 and 7 positions as crucial supposition for the antibacterial action of plant isoflavones and their metabolites. Demethyltexasin, an isoflavones' metabolite present in the human body through enterohepatic recycling of soya bean isoflavones (daidzein, genistein), showed the most potent antibacterial activity, especially against various strains of Staphylococcus aureus (including MDR and MRSA). The significance of this study is a deepening of the knowledge on isoflavones' SAR and identification of the antistaphylococcal activity of demethyltexasin, which suggest that metabolites of isoflavones can be even more potent antibacterial agents than their precursors.

• Klíčová slova
• antimicrobial activity, demethyltexasin, isoflavonoids, methicillin-resistant Staphylococcus aureus, minimum inhibitory concentration,
• MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• genistein farmakologie   MeSH
• gramnegativní bakterie účinky léků   MeSH
• isoflavony chemie   farmakologie   MeSH
• lidé MeSH
• methicilin farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• rostlinné extrakty farmakologie   MeSH
• Staphylococcus aureus účinky léků   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 6,7,4'-trihydroxyisoflavone MeSH Prohlížeč
• 7,8,4'-trihydroxyisoflavone MeSH Prohlížeč
• antibakteriální látky MeSH
• biochanin A MeSH Prohlížeč
• daidzein MeSH Prohlížeč
• genistein MeSH
• isoflavony MeSH
• methicilin MeSH
• rostlinné extrakty MeSH

Plants of the Amaryllidaceae family are known as producers of biologically active alkaloids. Besides these a variety of flavonoids, including flavones, chalcones and chromones, have been detected in the Amaryllidaceous plants. In this study, we have analysed 16 representatives of the family for the presence of isoflavonoids. The water/ethanolic extracts were analysed with HPLC-ESI-MS both without any pre-treatment and after immunoaffinity chromatography as a clean-up step. Four individual immunosorbents specific for biochanin A, daidzein and genistein were used. In addition, five enzyme-linked immunosorbent assays specific for the above-mentioned isoflavonoids and their derivatives have been used for the analysis of the extracts after fractionation by semi-preparative HPLC. Fifteen selected isoflavonoids were detected in the studied samples, and the amount of individual compounds ranged between ca. 0.8 and 400 ng/g of dry weight. This study extends the number of known isoflavonoid-producing families within the monocotyledonous plants.

• Klíčová slova
• Amaryllidaceae, ELISA, HPLC-ESI-MS, immunoaffinity chromatography, isoflavonoid,
• MeSH
• alkaloidy chemie   izolace a purifikace   farmakologie   MeSH
• elektronová paramagnetická rezonance MeSH
• ELISA MeSH
• genistein izolace a purifikace   MeSH
• isoflavony chemie   izolace a purifikace   farmakologie   MeSH
• liliovité chemie   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alkaloidy MeSH
• biochanin A MeSH Prohlížeč
• daidzein MeSH Prohlížeč
• genistein MeSH
• isoflavony MeSH

The aim of the study was to determine phytoestrogen content in fresh-cut legume forage. This issue has been much discussed in recent years in connection with the health and safety of feedstuffs and thus livestock health. The experiments were carried out on two experimental plots at Troubsko and Vatín, Czech Republic during June and July in 2015. Samples were collected of the four forage legume species perennial red clover (variety "Amos"), alfalfa (variety "Holyně"), and annuals Persian clover and Alexandrian clover. Forage was sampled twice at regular three to four day intervals leading up to harvest and a third time on the day of harvest. Fresh and wilted material was analyzed using liquid chromatography-mass spectrometry (LC-MS). Higher levels ( p < 0.05) of isoflavones biochanin A (3.697 mg·g (-1) of dry weight) and formononetin (4.315 mg·g (-1) of dry weight) were found in red clover than in other species. The highest isoflavone content was detected in red clover, reaching 1.001% of dry matter ( p < 0.05), representing a risk for occurrence of reproduction problems and inhibited secretion of animal estrogen. The phytoestrogen content was particularly increased in wilted forage. Significant isoflavone reduction was observed over three to four day intervals leading up to harvest.

• Klíčová slova
• Medicago, Trifolium, biochanin A, formononetin, isoflavones, phytoestrogens,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Isoflavones and coumestrol from dietary legumes are plant constituents showing multiple beneficial effects on humans. Owing to their ability to bind with mammalian estrogenic receptors and thereby intervention in several kinds of hormone-related cancers, they have received much attention. Soybean (Glycine max) is currently the major source of isoflavonoids in human diet. However, dozens of tropical and subtropical leguminous species remain unexplored for their isoflavonoids content. RESULTS: We have analyzed 55 extracts from 41 tropical and subtropical legume species used either in human or animal diet by high-performance liquid chromatography for the content of soy isoflavones, biochanin A, daidzein, daidzin, formononetin, genistein, genistin, sissotrin, ononin and the coumestan coumestrol. Genistein and biochanin A were the most abundant compounds. The highest content of genistein was found in aerial parts of Andira macrothyrsa, seeds of Pachyrhizus tuberosus and aerial parts of Calopogonium mucunoides (598, 250 and 184 µg g(-1), respectively) and biochanin A in aerial parts of Cratylia argentea, C. mucunoides and flowers of A. macrothyrsa (76, 53 and 40 µg g(-1), respectively). CONCLUSION: None of the samples tested was richer overall source of soy isoflavones and coumestrol than soybean; nevertheless several species (C. mucunoides or A. macrothyrsa) may serve as a promising source of individual compounds.

• MeSH
• dieta * MeSH
• Fabaceae chemie   MeSH
• genistein analýza   MeSH
• Glycine max chemie   MeSH
• isoflavony analýza   MeSH
• kumestrol analýza   MeSH
• lidé MeSH
• nadzemní části rostlin MeSH
• podpora zdraví MeSH
• rostlinné extrakty chemie   MeSH
• semena rostlinná chemie   MeSH
• tropické klima MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• biochanin A MeSH Prohlížeč
• genistein MeSH
• isoflavony MeSH
• kumestrol MeSH
• rostlinné extrakty MeSH

Complete separation of aglycones and glucosides of selected isoflavones (genistin, genistein, daidzin, daidzein, glycitin, glycitein, ononin, sissotrin, formononetin, and biochanin A) was possible in 1.5 min using an ultrahigh-pressure liquid chromatography (U-HPLC) on a different particular chemically modified stationary phases with a particle size under 2 microm. In addition, selected separation conditions for simultaneous determination of isoflavones together with a group of phenolic acids (gallic, protocatechuic, p-hydroxybenzoic, vanillic, caffeic, syringic, p-coumaric, ferulic, and sinapic acid) allowed separation of all 19 compounds in 1.9 min. Separations were conducted on a non-polar reversed phase (C(18)) and also on more polar phases with cyanopropyl or phenyl groups using a gradient elution with a mobile phase consisting of 0.3% aqueous acetic acid and methanol. Chromatographic peaks were characterised using parameters such as resolution, symmetry, selectivity, etc. Individual substances were identified and quantified using UV-vis diode array detector at wavelength 270 nm. Limits of detection (3S/N) were in the range 200-400 pg ml(-1). Proposed U-HPLC technique was used for separation of isoflavones and phenolic acids in samples of plant materials (Trifolium pratense, Glycine max, Pisum sativum and Ononis spinosa) after acid hydrolysis of the samples and modified Soxhlet extraction.

• MeSH
• genistein chemie   izolace a purifikace   MeSH
• Glycine max chemie   MeSH
• hrách setý chemie   MeSH
• hydroxybenzoáty chemie   izolace a purifikace   MeSH
• isoflavony chemie   izolace a purifikace   MeSH
• kyselina gallová analogy a deriváty   chemie   izolace a purifikace   MeSH
• kyselina vanilová chemie   izolace a purifikace   MeSH
• kyseliny kávové chemie   izolace a purifikace   MeSH
• kyseliny kumarové chemie   izolace a purifikace   MeSH
• molekulární struktura MeSH
• propionáty MeSH
• rostlinné extrakty chemie   izolace a purifikace   MeSH
• Trifolium chemie   MeSH
• vysokoúčinná kapalinová chromatografie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biochanin A MeSH Prohlížeč
• caffeic acid MeSH Prohlížeč
• daidzein MeSH Prohlížeč
• daidzin MeSH Prohlížeč
• ferulic acid MeSH Prohlížeč
• formononetin MeSH Prohlížeč
• genistein MeSH
• genistin MeSH Prohlížeč
• glycitein MeSH Prohlížeč
• glycitin MeSH Prohlížeč
• hydroxybenzoáty MeSH
• isoflavony MeSH
• kyselina gallová MeSH
• kyselina vanilová MeSH
• kyseliny kávové MeSH
• kyseliny kumarové MeSH
• p-coumaric acid MeSH Prohlížeč
• phenolic acid MeSH Prohlížeč
• propionáty MeSH
• protocatechuic acid MeSH Prohlížeč
• rostlinné extrakty MeSH
• sinapinic acid MeSH Prohlížeč
• syringic acid MeSH Prohlížeč