The content of 9 types of isoflavonoids (daidzein, glycitein, genistein, formononetin, biochanin A, coumestrol, daidzin, glycitin and genistin) in 34 domestic or imported raw beans including soybeans, 7 immature beans and 5 bean sprouts consumed in Japan were systematically analyzed. Each isoflavonoid was analyzed in total after acid hydrolysis to the aglycone, and intact individual isoflavonoids were also analyzed without hydrolysis. After the sample clean up, daidzein, glycitein, genistein, formononetin, biochanin A, daidzin, glycitin and genistin were determined by HPLC with a diode array detector and coumestrol was determined by spectrofluorimetry. The content and composition of isoflavonoids varied greatly between soybean sprouts, immature soybeans and mature beans of the same type but of different source. Isoflavonoid content was highest in mature soybeans. The composition of isoflavonoids differed in each growth stage of soybeans. In other beans, the largest content of isoflavonoids was found in mature chickpeas, but this value was less than 1/27 of the isoflavonoid content in mature soybeans. Thus, the contribution of beans other than soybeans to the daily intake of isoflavonoids in a Japanese diet is negligible.Key words ---isoflavonoid, bean, acid hydrolysis, high performance liquid chromatography, diode array detection, spectrofluorometric detection tivities 1) and reported to be protective against cancer, cardiovascular diseases and osteoporosis. [3][4][5][6][7][8][9] Much research has been reported about the content of isoflavonoids in soybeans and soybean-derived processed foods. [10][11][12][13][14][15][16][17][18][19][20][21][22][23] In contrast, there are few reports about the isoflavonoid content in beans other than soybeans. 11,12,18,23) Japanese people are reported to ingest isoflavonoids mainly through the consumption of soybeans and its derived processed foods. 20) Recently, we estimated that the Japanese daily intake of isoflavonoids from soybeans and soybean-based processed foods is 27.80 mg per day (daidzein 12.02 mg, glycitein 2.30 mg and genistein 13.48 mg).24) However, isoflavonoid intake from the consumption of immature beans, sprouts and beans other than soybeans has not been elucidated. Here we have measured the content of isoflavonoids in mature and immature beans and bean sprouts consumed in Japan, and have compared the content and composition variation between different types and different growth stages of the beans. MATERIALS AND METHODSMaterials ---Genistein, formononetin and biochanin A were purchased from Extrasynthèse (Genay, France). Daidzein, daidzin, genistin, glycitein and glycitin were from Fujicco Co., Ltd. (Kobe, Japan). Coumestrol was obtained from Fluka Chemie AG (Bucks, Switzerland). Flavone, 2,6-dit-butyl-4-methylphenol (BHT) and dimethyl sulfoxide (DMSO) were from Wako Pure Chemical Industries, Ltd. (Osaka, Japan). The chemical structures of these isoflavonoids and flavone are shown in Fig. 1. Acetonitrile, ethanol, n-hexane and methanol were analytical grade...
Duplicate hospital diet samples obtained over 1 week in 2001 were analysed to estimate the daily intake of plasticizers and the results were compared with those obtained in 1999. The plasticizers quantified in this study were: dibutyl phthalate, butylbenzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), di(2-ethylhexyl) adipate (DEHA), diisononyl adipate (DINA) and O-acetyl tributyl citrate (ATBC). Dipropyl, dipentyl, dihexyl and dicyclohexyl phthalate were also analysed but not detected. The analytical procedure for this follow-up study was essentially the same as in the previous one. Detection limits were 0.1-15.6 ng g(-1) for each plasticizer. One-week duplicate diet samples provided by three hospitals in three remote prefectures of Japan were analysed as individual meals. DEHP was detected at 6-675 ng g(-1) in 62 of 63 meals, significantly lower levels compared with those detected in 1999. Levels of DEHA and DINP also decreased. The mean intake of plasticizers estimated from all samples was 160 microg DEHP day(-1), 12.5 microg DEHA day(-1), 4.7 microg DINP day(-1) and 3.4 microg BBP day(-1). Levels of DINA were relatively high in meals from one hospital: in those meals, the average daily intake was 1338 microg day(-1). Those of ATBC were also higher in meals from another hospital: the average daily intake was 1228 microg day(-1). The sources of DINA and ATBC can be cling-film or sausage packaging.
Plasticizers in duplicate diet samples obtained over 1 week were analysed in order to estimate daily intake. The phthalate esters were as follows: diethyl, dipropyl, dibutyl, dipentyl, dihexyl, butylbenzyl, dicyclohexyl, di(2-ethylhexyl), dioctyl, diisooctyl (mixture of isomers) and diisononyl (mixture). Di(2-ethylhexyl) adipate was also determined. Homogenized samples of composite meals were extracted with acetonitrile, lipids were removed by extraction into n-hexane and the acetonitrile layer was cleaned using Florisil and Bondesil PSA dual layer column. Phthalates were determined by GC/MS (SIM). Phthalate recovery from the fortified food mixture by this method was 62.5-140.8%. Quality assurance as assessed by three laboratories indicated coefficient of variance in the levels of detected phthalates in same lot samples as below 10%. Detection limits were 0.1-23 ng/g for each phthalate. One-week duplicate diet samples provided by three hospitals in three remote prefectures of Japan were analysed as individual meals. In all 63 samples, DEHP was present at the highest level among all phthalates in the range 10-4400 ng/g. The intake of plasticizers estimated from all samples was 519 microg DEHP/day, 86 microg DEHA/day, 65 microg DINP/day, and 4.7 microg BBP/day. Calculated DEHP in 2-day samples out of 21 days exceeded EU TDI for a person of 50 kg body weight (1850 microg per day). Disposable PVC gloves used during the preparation of meals were suspected as the source of the high DEHP content. One-day intake of the other phthalates and DEHA was below 7% of TDI in all cases. High concentrations of DEHP (5990 ng/g) was found in baby food used in quality assurance work. The source of contamination was the PVC-tube used during production and was effectively reduced by replacing the tube by one made of stainless steel.
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