To detect trace amounts of arsenic, lead, cadmium and tin in soft drinks, a simple and rapid determination without sample pretreatment was developed. A sample of a soft drink was diluted with distilled water and examined by electrothermal atomic absorption spectrometry with addition of nickel nitrate as a matrix modifier. Detection limits of arsenic, lead, cadmium and tin in the samples were 0.025 ppm (as As2O3), 0.025 ppm, 0.005 ppm and 0.3 ppm, respectively.The developed method was applied to the determination of arsenic, lead, cadmium and tin in 13 kinds of soft drinks (total 150 samples). The amounts of arsenic and lead in the soft drinks were less than 0.025 ppm in all samples: cadmium and tin were detected in only 2 (0.006 similar to 0.019 ppm) and 5 (6.9 similar to 86 ppm) of 150 samples, respectively. The proposed method is simple and rapid for determination of arsenic, lead, cadmium and tin in soft drinks.
鶏肉,豚肉及び牛肉中に残留するストレプトマイシン(SM)のHPLCによる簡易迅速定量法を確立した.前処理用カラムとしてC8ミニカラムを用いた肉中SMの前処理と,分析用カラムとして Nucleosil 5C18を用いたニンヒドリンによるポストカラム蛍光誘導体化法を検討した.食肉を3.6%過塩素酸溶液と共にホモジナイズし,組織及びタンパク質を遠心除去しながらSMの抽出を行い,次にC8ミニカラムを用いたイオン対クロマトグラフィーでSMの前処理を行った.又,HPLCは移動相に20mM 1,2-エタンジスルホン酸ナトリウム,5mM 1-オクタンスルホン酸ナトリウム及び5mMニンヒドリンを含む水-アセトニトリル混液(86:14)を,反応液に0.3M水酸化ナトリウム溶液をそれぞれ用い,励起波長400nm,蛍光波長495nmで検出を行った.食肉に2μg/g添加した場合の回収率は66.7%,検出限界は0.5μg/gであった.なお,1検体の分析には約3時間を要した.
Abstract A method for the production and isolation of gram quantities of nivalenol and fusarenon-X, trichothecene mycotoxins, is presented. Fusarium graminearum F-1465 was inoculated and cultured on the pressed barley, and the cultured product was extracted with acetonitrile. The crude extracts were subjected to silica gel column chromatography and then to centrifugal partition chromatography (CPC) using two-phase solvent system n-butanol/water and chloroform/methanol/water. The simple procedures were advantageous for the large scale purification of two toxins from cultured pressed barley medium because it was more time and yield effective. Starting from 1 Kg of the pressed barley substrate, 0.34 g of crystalline nivalenol (purity 103%) was obtained by recrystallization of CPC fraction from hot methanol and 0.78 g of fusarenon-X (purity 77%) was obtained directly from CPC fraction by evaporating to dryness.
