Validation of ELISAs for Isoflavones and Enterolactone for Phytoestrogen Intake Assessment in the French Population.

Phytoestrogens are dietary compounds with low estrogenic activity. The two main categories in the French diet are isoflavones from pulses and enterolignans metabolized by the gut flora from various lignans found in fruits, vegetables, grains, and beverages. Isoflavones and lignans have different effects on human physiology and can antagonize each other. Comprehensive lists of phytoestrogen sources were constructed based on measurements and literature data. The 24 h and 48 h dietary recalls were proposed to the volunteers of the ISOLED cohort (NCT03421184). Urine and plasma samples from these volunteers were assayed for genistein, daidzein, equol, and enterolactone. A dietary score was constructed considering the pharmacokinetic characteristics of these compounds. Correlation analyses were applied to fluid concentrations associated with dietary scores. Pearson correlations reached 0.921 (p < 0.001) for urineIF, 0.900 (p < 0.001) for plasmaIF, 0.764 (p < 0.001) for urineENL, and 0.723 (p < 0.001) for plasmaENL. ELISAs associated with careful intake assessments proved to be good tools for phytoestrogens' exposure estimation.

New Evaluation of Isoflavone Exposure in the French Population.

The study relates the present evaluation of exposure to estrogenic isoflavones of French consumers through two approaches: (1) identification of the isoflavone sources in the French food offering, (2) a consumption-survey on premenopausal women. For the foodstuff approach 150 food-items were analysed for genistein and daidzein. Additionally, 12,707 labels of processed-foods from French supermarket websites and a restaurant-supplier website were screened, and 1616 foodstuffs of interest were retained. The sources of phytoestrogens considered were soy, pea, broad bean and lupine. A price analysis was performed. A total of 270 premenopausal women from the French metropolitan territory were interviewed for their global diet habits and soy consumption and perception. In supermarkets, there were significantly less selected foodstuffs containing soy than in restaurant (11.76% vs. 25.71%, p < 0.01). There was significantly more soy in low price-foodstuff in supermarket (p < 0.01). Isoflavone levels ranged from 81 to 123,871 µg per portion of the analyzed soy containing foodstuff. Among the women inquired 46.3% claimed to have soy regularly. Isoflavone intake >45 mg/day is associated to vegan-diet (p < 0.01). In total, 11.9% of soy-consumers had a calculated isoflavone intake >50 mg/day. This dose can lengthen the menstrual cycles. The actual exposure to phytoestrogen is likely to have an effect in a part of the French population.

Rapid lateral-flow immunoassay for the quantum dot-based detection of puerarin.

In this study, a rapid (within 10min) quantitative lateral-flow immunoassay using a quantum dots (QDs)-antibody probe was developed for the analysis of puerarin (PUE) in water and biological samples. The competitive immunoassay was based on anti-PUE monoclonal antibody conjugated with QDs (detection reagent). Secondary antibody was immobilized on one end of a nitrocellulose membrane (control line) and PUE-bovine serum albumin conjugate was immobilized on the other end (test line). In the quantitative experiment, the detection results were scanned using a membrane strip reader and a detection curve (regression equation: y=-0.11ln(x)+0.979, R(2)=0.9816) representing the averages of the scanned data was obtained. This curve was linear from 1 to 10µg/mL. The IC50 value was 75.58ng/mL and the qualitative detection limit of PUE was 5.8ng/mL. The recovery of PUE added to phosphate-buffered saline and biological samples was in the range of 97.38-116.56%. To our knowledge, this is the first report of the quantitative detection of a natural product by QDs-based immunochromatography, which represents a powerful tool for rapidly screening PUE in plant materials and other biological samples.

Flavonoid and lignan intake in a Mediterranean population: proposal for a holistic approach in polyphenol dietary analysis, the Moli-sani Study.

BACKGROUND/OBJECTIVES: The objective of this study is to extract and assess data on the dietary intake of flavonoids and lignans in a healthy free-living Mediterranean population, using newly updated harmonized European Union food composition data. This work also aimed at analyzing in a holistic way the total content of the diet in major classes of polyphenols. SUBJECTS/METHODS: Six thousand nine hundred and eighty-one men and 7048 women (aged ⩾ 35 years) of the Moli-sani cohort, randomly recruited from the general population, were analyzed. The European Prospective Investigation into Cancer (EPIC) and Nutrition-Food Frequency Questionnaire was used for dietary assessment. The polyphenol content of each food group was evaluated using Eurofir BioActive Substances in Food Information System and the United States Department of Agriculture food composition tables (FCTs), when data were missing. Flavonol, flavone, flavanone, flavanol, anthocyanin, isoflavone and lignan intakes were calculated and polyphenol antioxidant content (PAC) score (-28, 28) constructed, to assess the total content of the diet in these nutrients. RESULTS: Seasonal and citrus fruits, leafy, grain, pod and root vegetables, and onions and garlic accounted for different proportions (11-70%) of the total intake of different polyphenols. Within the Moli-sani population, men or older, or no/former smokers, or physically active or obese/overweight individuals presented higher consumption of flavonoids, lignans and PAC score (P for all <0.01). Multiple regression analysis showed that PAC score and its seven components were positively associated with Mediterranean diet (MeD) adherence in both genders (ß-coefficient >0, P<0.001). In addition, 1 unit increase in PAC score was associated with 7.1-7.8% increase in the likelihood of high MeD adherence (P<0.001). CONCLUSIONS: The intake of flavonoids and lignans in an European Union population was calculated using harmonized European Union FCT data. In addition, a holistic approach in dietary analysis of polyphenol intake was proposed.

Process of formulating USDA's Expanded Flavonoid Database for the Assessment of Dietary intakes: a new tool for epidemiological research.

The scientific community continues to be interested in potential links between flavonoid intakes and beneficial health effects associated with certain chronic diseases such as CVD, some cancers and type 2 diabetes. Three separate flavonoid databases (Flavonoids, Isoflavones and Proanthocyanidins) developed by the USDA Agricultural Research Service since 1999 with frequent updates have been used to estimate dietary flavonoid intakes, and investigate their health effects. However, each of these databases contains only a limited number of foods. The USDA has constructed a new Expanded Flavonoids Database for approximately 2900 commonly consumed foods, using analytical values from their existing flavonoid databases (Flavonoid Release 3.1 and Isoflavone Release 2.0) as the foundation to calculate values for all the twenty-nine flavonoid compounds included in these two databases. Thus, the new database provides full flavonoid profiles for twenty-nine predominant dietary flavonoid compounds for every food in the database. Original analytical values in Flavonoid Release 3.1 and Isoflavone Release 2.0 for corresponding foods were retained in the newly constructed database. Proanthocyanidins are not included in the expanded database. The process of formulating the new database includes various calculation techniques. This article describes the process of populating values for the twenty-nine flavonoid compounds for every food in the dataset, along with challenges encountered and resolutions suggested. The new expanded flavonoid database released on the Nutrient Data Laboratory's website would provide uniformity in estimations of flavonoid content in foods and will be a valuable tool for epidemiological studies to assess dietary intakes.

HPLC-DAD-ELSD Combined Pharmacodynamics and Serum Medicinal Chemistry for Quality Assessment of Huangqi Granule.

OBJECTIVE: To more scientifically and reasonably control the quality of Huangqi Granules, preliminary studies on the pharmacodynamics and serum pharmacochemistry of this medicine were performed. DPPH and MTT experiments showed that water extracts of Huangqi Granules had good antioxidant activity and increased immunity. Timed blood samples collected 5 min, 15 min, and 30 min after oral administration of a set amount of Huangqi Granules were collected and tested using UPLC-ESI-MS/MS. As a result, calycosin-7-O-ß-D-glucoside, ononin, calycosin, astragaloside IV, and formononetin were found to exist in rat blood after dosing, indicating that the five chemical compounds might have pharmacological activity, and based on this result, they were designated biomarkers for quality control of Huangqi Granules. Consequently, a simple, rapid and efficient method was developed in the present study for the simultaneous determination of the five characteristic compounds in Huangqi Granules using HPLC-DAD-ELSD. MATERIALS AND METHODS: The separation was performed using an Agilent Hypersil ODS column (4.6 × 250 mm, 5 µm) at 30 ℃. The mobile phase was composed of water (solvent A) and acetonitrile (solvent B) with a flow rate of 1 mL/min. The drift tube temperature of the ELSD system was set to 85 ℃, and the nitrogen pressure was 3.5 bar. RESULTS: All five characteristic compounds had good linear behavior with r2 values greater than 0.9972. The recoveries varied from 96.31% to 101.22%. Subsequently, the developed method was applied to evaluate the quality of Huangqi Granules from different batches, and hierarchical clustering analysis (HCA) was used to analyze the classification of the samples based on the values of the five compounds. CONCLUSION: The established HPLC method combined with HCA proved to be effective to evaluate the quality of Huangqi Granules.

Isoflavones in food supplements: chemical profile, label accordance and permeability study in Caco-2 cells.

Consumers nowadays are playing an active role in their health-care. A special case is the increasing number of women, who are reluctant to use exogenous hormone therapy for the treatment of menopausal symptoms and are looking for complementary therapies. However, food supplements are not clearly regulated in Europe. The EFSA has only recently begun to address the issues of botanical safety and purity regulation, leading to a variability of content, standardization, dosage, and purity of available products. In this study, isoflavones (puerarin, daidzin, genistin, daidzein, glycitein, genistein, formononetin, prunetin, and biochanin A) from food supplements (n = 15) for menopausal symptoms relief are evaluated and compared with the labelled information. Only four supplements complied with the recommendations made by the EC on the tolerable thresholds. The intestinal bioavailability of these compounds was investigated using Caco-2 cells. The apparent permeability coefficients of the selected isoflavonoids across the Caco-2 cells were affected by the isoflavone concentration and product matrix.

Rapid determination of major bioactive isoflavonoid compounds during the extraction process of kudzu (Pueraria lobata) by near-infrared transmission spectroscopy.

Near-infrared (NIR) spectroscopy has been developed into an indispensable tool for both academic research and industrial quality control in a wide field of applications. The feasibility of NIR spectroscopy to monitor the concentration of puerarin, daidzin, daidzein and total isoflavonoid (TIF) during the extraction process of kudzu (Pueraria lobata) was verified in this work. NIR spectra were collected in transmission mode and pretreated with smoothing and derivative. Partial least square regression (PLSR) was used to establish calibration models. Three different variable selection methods, including correlation coefficient method, interval partial least squares (iPLS), and successive projections algorithm (SPA) were performed and compared with models based on all of the variables. The results showed that the approach was very efficient and environmentally friendly for rapid determination of the four quality indices (QIs) in the kudzu extraction process. This method established may have the potential to be used as a process analytical technological (PAT) tool in the future.

Assessment of the estrogenicity of the diet of a healthy female Spanish population based on its isoflavone content.

Phytoestrogens are natural components of plants consumed by humans. The hormonal activity of these substances has long been known. Various in vitro tests have demonstrated the agonistic or antagonistic estrogenic activity of some phytoestrogens. The objective of this study was to estimate the supply of isoflavones in the diet of a healthy adult female population and to assess its estrogenic effect. The diet was assessed by questionnaire and the estrogenicity of the estimated isoflavone content was tested by E-screen, finding a mean total estrogenic capacity of 0.129 × 10⁻¹° eq.E2 (12.9 pmol day⁻¹), corresponding to a daily isoflavone intake of 265.8 µg day⁻¹. This study offers a preliminary insight into the phytoestrogen content of the diet of a healthy active population of Spanish women. The effects of this additional hormonal burden are highly controversial, and this approach to estimating dietary phytoestrogen intake of specific populations may help to elucidate its implications for human health.

A modified QuEChERS method as sample treatment before the determination of isoflavones in foods by ultra-performance liquid chromatography-triple quadrupole mass spectrometry.

This paper reports the development of an analytical method for the determination of isoflavones in legumes using LC-MS/MS. A modified approach of the QuEChERS methodology was used to extract the analytes from the food samples. The proposed method includes a two-step extraction process and allows the determination of isoflavones in pulses without the need of a clean-up step. Use of this methodology for the extraction of natural occurring substances provides advantages such as simplicity and ease of use, especially taking into account the complexity of food matrices. The method was applied successfully for the determination of eight isoflavones, including aglycones and glucosides, in legumes of Spanish origin (chickpeas, lentils and beans from the region of Castilla y León). The target compounds were the glucosides daidzin, glycitin and genistin, and the aglycones daidzein, glycitein, genistein, formononetin, and biochanin A. The detection limits were in the 0.7 µg L(-1) to 1.5 µg L(-1) range for formononetin and glycitin respectively. Recoveries ranged from 72% to 119%, and standard deviations lower than 25% were obtained for the inter-day precision. The method described is precise, selective and not time-consuming.

Identification of multiple constituents in the traditional Chinese medicine formula Zhi-zi-chi decoction and rat plasma after oral administration by liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry.

RATIONALE: Liquid chromatography (LC) coupled to positive electrospray ionization (ESI) tandem mass spectrometry (MS/MS) employing a time-of-flight tandem mass spectrometer was established to identify multi-components of Zhi-zi-chi decoction, a traditional Chinese medicine formula, and the constituents in rat plasma after oral administration of Zhi-zi-chi decoction. METHODS: The LC separation was achieved on a C(18) column. The mobile phase consisted of acetonitrile/0.2% formic acid with gradient program. The quadrupole time-of-flight (Q-TOF) mass spectrometer was operated in the positive ion mode with an electrospray ionization source (ESI+). The capillary voltage of the ion source was set at 4500 V and the capillary exit was 90 V. The nebulizer pressure was maintained at 1.2 bar. Hexapole radio frequencies 1 and 2 were set to 200 Vpp and 250 Vpp, respectively. RESULTS: A total 47 compounds in the Zhi-zi-chi decoction and 24 constituents in rat plasma after oral administration of Zhi-zi-chi decoction were identified. Of the 47 detected compounds in the Zhi-zi-chi decoction, 15 were identified by comparing the retention time and MS data with that of reference compounds and the rest were identified by MS analysis and retrieving the reference literature. Of the identified 24 compounds in rat plasma, 19 were the original form of the compounds absorbed from the 47 detected compounds, and the other five were the metabolites of the compounds existing in the Zhi-zi-chi decoction. CONCLUSIONS: A fast and sensitive LC/Q-TOF MS method has been developed and successfully utilized to screen the active ingredients of a Chinese medical formula, Zhi-zi-chi decoction, for the first time. The results indicated that the 24 compounds identified in rat plasma were the potential active ingredients of Zhi-zi-chi decoction, which provided helpful chemical information for further pharmacology and active mechanism research on Zhi-zi-chi decoction and other traditional Chinese medicines.

Chemical and biological assessment of Angelica herbal decoction: comparison of different preparations during historical applications.

The commonly used Angelica herbal decoction today is Danggui Buxue Tang (DBT), which is a dietary supplement in treating menopausal irregularity in women, i.e. to nourish "Qi" and to enrich "Blood". According to historical record, many herbal decoctions were also named DBT, but the most popular formulation of DBT was written in Jin dynasty (1247 AD) of China, which contained Astragali Radix (AR) and Angelicae Sinensis Radix (ASR) with a weight ratio of 5:1. However, at least two other Angelica herbal decoctions recorded as DBT were prescribed in Song (1155 AD) and Qing dynasties (1687 AD). Although AR and ASR are still the major components in the DBT herbal decoctions, they are slightly varied in the herb composition. In order to reveal the efficiency of different Angelica herbal decoctions, the chemical and biological properties of three DBT herbal extracts were compared. Significantly, the highest amounts of AR-derived astragaloside III, astragaloside IV, calycosin and formononetin and ASR-derived ferulic acid were found in DBT described in 1247 AD: this preparation showed stronger activities in osteogenic, estrogenic and erythropoetic effects than the other two DBT. The current results supported the difference of three DBT in chemical and biological properties, which could be a result of different herbal combinations. For the first time, this study supports the popularity of DBT described in 1247 AD.

[The importance of soy in Mexico, its nutritional value and effect on health]. / La historia del uso de la soya en México, su valor nutricional y su efecto en la salud.

Soy protein has been used in several Latin-American countries including Mexico in various food programs with the purpose to improve the nutritional status of the population due to the high nutritional value and its relatively low cost that was maintained for some time. In the present work, the use and research on soy in Mexico since 1970 is described. In addition, this review shows the effects of the different components of soy, in particular its protein and the isoflavones on health, the mechanism of action of soy protein to reduce cholesterol and triglycerides, and insulin secretion, as well as its glycemic response, and finally, the recommendations of soy protein consumption to obtain a health benefit.

La historia del uso de la soya en México, su valor nutricional y su efecto en la salud / The importance of soy in Mexico, its nutritional value and effect on health

La proteína de soya se ha utilizado en algunos países latinoamericanos, incluido México, en diversos programas de alimentación; el propósito ha sido el de mejorar el estado nutricional de la población debido a su elevado valor nutricio y su costo relativamente bajo que mantuvo por algún tiempo. En este trabajo se describen los usos y la investigación que se ha llevado a cabo sobre la soya en México desde 1970. Además, se revisan los efectos de los diferentes componentes de la soya, en particular de su proteína y las isoflavonas, sobre la salud, su mecanismo de acción en la reducción del colesterol y los triglicéridos y la disminución de la secreción de insulina, así como su respuesta glucémica; por último, se delinean las recomendaciones del consumo de la proteína de soya parar obtener un beneficio en la salud.

Soy protein has been used in several Latin-American countries including Mexico in various food programs with the purpose to improve the nutritional status of the population due to the high nutritional value and its relatively low cost that was maintained for some time. In the present work, the use and research on soy in Mexico since 1970 is described. In addition, this review shows the effects of the different components of soy, in particular its protein and the isoflavones on health, the mechanism of action of soy protein to reduce cholesterol and triglycerides, and insulin secretion, as well as its glycemic response, and finally, the recommendations of soy protein consumption to obtain a health benefit.

Rapid separation and identification of 54 major constituents in Buyang Huanwu decoction by ultra-fast HPLC system coupled with DAD-TOF/MS.

Buyang Huanwu Decoction (BYHWD), is a well-known traditional Chinese preparation consisting of Radix Astragali, Radix Angelicae Sinensis, Rhizoma Ligustici Chuanxiong, Radix paeoniae Rubra, Flos Carthami, Semen Persicae and Lumbricus. An ultra-fast high-performance liquid chromatography (HPLC) method coupled with diode array detection (DAD) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF/MS) has been developed for rapid separation and structural identification of constituents in BYHWD. Using an ultra-fast HPLC system with short columns (4.6 x 50 mm, 1.8 microm), the total analysis time for this complex prescription is less than 30 min. With various fragmentor voltages in TOF/MS, accurate mass measurements (less than 5 ppm error) for molecular ions and characteristic fragment ions could represent reliable identification criteria for these compounds. Fifty-four major constituents from BYHWD sample, including four C-glycosyl quinochalcones, four flavonoid O-glycosides, sixteen isoflavones, six monoterpene glycosides, eight saponins, four organic acids and five amino acids, were identified or tentatively characterized based on their retention times, DAD and TOF/MS data. All the compounds were further assigned in the seven individual crude drugs. In conclusion, the ultra-fast HPLC with DAD-TOF/MS is a highly useful and efficient technique to separate and identify constituents in complex matrices of herbal medicines or preparations.

Chemical and biological assessment of a chinese herbal decoction containing Radix Astragali and Radix Angelicae Sinensis: Determination of drug ratio in having optimized properties.

Danggui Buxue Tang (DBT), a Chinese medicinal decoction that is commonly used as a dietary supplement in treating woman with menopausal irregularity, contains two herbs: Radix Astragali (Huangqi) and Radix Angelicae Sinensis (Danggui). The ratio of Radix Astragali and Radix Angelicae Sinensis used in DBT should be 5:1 as described in China in 1247 A.D.; however, the rationale of this formula has not been given. Here, the chemical and biological properties of DBT, prepared from different ratios of the drugs, were determined. Significantly, higher amounts of Radix Astragali-derived astragaloside IV, calycosin, and formononetin and Radix Angelicae Sinensis-derived ferulic acid were found in DBT with Radix Astragali and Radix Angelicae Sinensis in a 5:1 ratio. By using the biological effects of DBT in stimulating osteoblast proliferation, estrogen promoter activation, and anti-platelet aggregation activity, the drug ratio of 5:1 produced the best effects. In addition, the use of ethanol-treated Radix Angelicae Sinensis enhanced the efficacy of DBT, and the treatment further increased the solubilities of chemical constituents. By analyzing the correlation of chemical and biological results, several chemicals showed positive correlation with DBT-induced bioactivities. The current results support the ancient formulation of DBT, and the identified chemicals could serve as markers for quality control of DBT.

A newly constructed and validated isoflavone database for the assessment of total genistein and daidzein intake.

The principal phyto-oestrogens (PO) in food are isoflavones, lignans, coumestans and prenylated flavonoids, with isoflavones and lignans being the most commonly found in UK diets. Until recently obtaining accurate data on the PO content of foods was hampered by lack of suitable analytical methods and validation techniques. Furthermore, although PO data exist for some foods, these foods may not be available in the UK. The aim of the present study was to construct a new, comprehensive isoflavone (total genistein + daidzein) database. Using data, mainly from recent GC-MS analysis, for approximately 300 foods available in the UK, and extensive recipe calculations, a new database was constructed containing approximately 6000 foods allocated an isoflavone value. By analysing 7 d weighed food diaries, the database was subsequently used to estimate isoflavone intake in two groups of healthy volunteers, omnivores (n 9) and vegetarians (n 10). Mean isoflavone intake in the vegetarian and omnivorous group was 7.4 (sem 3.05) and 1.2 (sem 0.43) mg/d, respectively. Mean intake for the total group was 4.5 (sem 1.89) mg/d. Main food sources of isoflavones for the vegetarian group were soya milk (plain), meat-substitute foods containing textured vegetable protein and soya protein isolate, soya mince, wholemeal bread and rolls, white bread and rolls, croissants and pitta breads, beans, raisins and soya sauce. Main food sources of isoflavones for the omnivorous group were soya yogurts, wholemeal bread and rolls, white bread and rolls, garlic bread, nan bread and brown bread, sultanas and scones.

Reproductive toxicity assessment of chronic dietary exposure to soy isoflavones in male rats.

Epidemiologic and experimental data suggest that consumption of diets that are rich in isoflavones may decrease cancer risk in the breast, prostate, and other tissues. Isoflavones such as genistein and daidzein are structurally similar to endogenous estrogens, and demonstrate both estrogenic and weak anti-estrogenic activities; these activities may underlie the impaired fertility and reproductive tract disorders reported in animals exposed to high doses of isoflavones. To identify possible effects of isoflavones on male fertility, we evaluated reproductive parameters in Wistar-Unilever rats receiving dietary exposure to PTI G-2535, a characterized mixture of soy-derived isoflavones containing 45% genistein, 23% daidzein, and 4% glycitein. Beginning at 10 weeks of age, rats received chronic dietary exposure to the soy isoflavone mixture (200 or 2000 mg/kg diet) for a minimum of 12 months. Controls received unsupplemented chow diet only for the same period. Dietary exposure to isoflavones induced no gross toxicity or alterations in body weight gain. Absolute and relative weights of the testis and epididymis in groups receiving high or low doses of isoflavones were comparable to those of controls, and histopathologic evaluations demonstrated that testicular morphology was similar in all study groups. Isoflavone exposure had no significant effects on spermatid count, sperm production, or sperm morphology in any group. These data suggest that the reproductive system of adult male rats is relatively insensitive to isoflavone toxicity at dose levels that demonstrate significant activity in cancer chemoprevention, and that male reproductive function is unlikely to be affected by long-term administration of isoflavones for cancer prevention or other purposes. The results of this study conducted in adult male rats differ from the significant alterations in reproductive parameters that have been reported in female rats receiving prenatal or juvenile exposure to isoflavones.

Quality, labeling accuracy, and cost comparison of purified soy isoflavonoid products.

OBJECTIVES: To evaluate the labeling accuracy and product uniformity of available soy isoflavone products in the eastern Washington State region for 13 products and to perform a cost comparison based on the isoflavone content in milligrams for 11 products. DESIGN: Thirteen (13) isoflavone products (7 tablet and 6 capsule formulations) were randomly obtained from health food, grocery, and pharmacy outlets in eastern Washington State. Four different samples of the same product were extracted using 75% ethanol. Each sample was analyzed for isoflavone content using a gradient high-performance liquid chromatography (HPLC) method. Pure isoflavonoid standards were used to quantify the content of genistein, daidzein, and glycitein and their respective glycosides. The amount of total isoflavonoids per purchased product was then divided into its purchase price in order to make cost comparisons between the products based on a 50 mg/d dose. RESULTS: The weight variation within each product was generally small (<4%). However, there was significant variability in the composition of the products. Only 4 of the 13 products contained at least 90% of the isoflavone content claimed on the label and 2 of products contained impurities in the HPLC chromatogram that exceeded 40%. There was no difference in the total isoflavonoid contents of the 2 identical products made by the same manufacturer, but the percentages of the main components had changed significantly over time. Based on a 50-mg isoflavone per day dose, the cost of a 30-day supply ranged from $3.20 to $65.88. CONCLUSION: There is a lack of uniformity among the products tested and the majority (67%) of the products contained less than 90% of labeled amounts. There is significant variability in the compositions between the products and in the composition of the same product over time. Consumers cannot trust isoflavonoid product labels to represent the product's content accurately or that product pricing is a reflection of isoflavone content.

Combined in situ and in vitro assessment of the estrogenic activity of sewage and surface water samples.

In order to investigate the estrogenic activities of two municipal sewage treatment plant (STP; sites A and B) effluents and of Rhine water sampled at Worms (site C; Rhine-Neckar triangle, Germany), data from in situ experiments measuring hepatic vitellogenin expression from caged rainbow trout (Oncorhynchus mykiss) were compared with data from in vitro bioassays (yeast estrogen screen [YES], ER luciferase assay with HEK 293 cells [HEK], primary rainbow trout hepatocytes [PH]) and chemical analysis. Three sampling campaigns were carried out at each site between November 2000 and September 2001. Vitellogenin (VTG)-mRNA expression in male rainbow trout exposed for two weeks ranged from 3 +/- 5 to 619 +/- 188 and from 226 +/- 38 to 3373 +/- 1958 pg/microg total RNA at sites A and B, respectively. E2-equivalents obtained from the in vitro bioassays gave values up to 0.21 +/- 0.04 nM (57.3 +/- 10.2 ng/l, PH), 0.07 +/- 0.03 nM (20.2 +/- 6.9 ng/l; YES) and 0.008 +/- 0.002 nM (2.1 +/- 0.7 ng/l; HEK). In contrast, in one-year-old rainbow trout exposed at site C, no VTG-mRNA induction could be observed after two weeks of exposure. In vitro bioassays (YES, HEK, PH) indicated estrogenic activity at site C, which, however, was lower than at the investigated STP effluents. Chemical analysis of representative water samples from site A identified steroidal estrogens up to 5.6 ng/l 17beta-estradiol (E2), 19 ng/l estrone as well as 1.5 ng/l 17alpha-ethinylestradiol. Furthermore, the sum of fecal- and phytosteroids, resorcyclic lactones, and flavonoid concentrations were 280 (A) and 1.200 ng/l (B). In addition, site C (river Rhine) contained 3.9 ng/l E2 and 250 ng/l of fecal- and phytosteroids, respectively. Thus, STP effluents and Rhine water contain biologically relevant concentrations of estrogenic compounds, the activity of which can be detected by means of various bioassays.