The effects of a 120-day feeding of vitamin E (VE)-deficient diet on hepatic antioxidative enzymes such as glutathione peroxidase, glutathione reductase and glutathione S-transferase were investigated in Wistar male and female rats gonadectomized at 3 weeks of age. Dietary VE deficiency significantly increased malondialdehyde concentration in hepatic homogenate of both sexes, regardless of gonadectomy, but had little effect on the activities of the enzymes studied. The results suggest that VE itself, not cytosolic antioxidative enzymes, plays a major role in suppressing lipid peroxidation on hepatic membranes, without any sex-difference.

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A simple gas chromatographic (GC) method has been developed to determine trace amounts of formaldehyde (HCHO) in tap water and commercially available mineral water. HCHO was reacted with O-(2, 3, 4, 5, 6-pentafluorobenzyl) oxyamine, and the product, HCHO-oxime derivative, was determined by GC using a capillary column. The HCHO can be detected as its pentafluorobenzyloxime, by using an electron capture detector, at levels of 0.1pg. Finally, 3.85-14.8μg/L and 4.88-9.23μg/L of HCHO were detected in tap water of 6 cities and 3 commercial mineral waters in bottles made of polyethylene terephthalate, respectively. Commercial mineral water in glass bottles and paper packages contained 0.16 and 0.20μg/L of HCHO, respectively.

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A method was developed for assay of progesterone used as an anabolic agent by applying a commercially available enzyme immunoassay (ETA) kit for diagnosis of pregnancy in cattle (by measuring progesterone in whole milk) to the measurement of progesterone in beef. Beef was homogenized with acetonitrile, and progesterone was extracted into dichloromethane. The dichloromethane phase was concentrated and purified by Sephadex LH-20 column chromatography. The concentrated hexane-benzene-methanol (85:10:5) eluate was taken up in buffer solution, and the solution was subjected to enzyme immunoassay using the kit.
The mean recoveries of progesterone in beef fortified with 1-10ppb were 116-130%. A good correlation between the values obtained by the ETA method and by HPLC was obtained for progesterone added to beef. The detection limit of progesterone was about 1ppb in the samples. This procedure is useful for initial screening of residual progesterone in beef.

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Development of a procedure for simultaneous analysis of triadimefon, triadimenol, triapentenol, pacrobutrazole, diniconazole, propiconazole, benalaxyl and bitertanol in vegetables and fruits is described. The pesticides were extracted from the sample and analyzed by FTD-GC. Recoveries of the pesticides spiked at 0.2ppm were 67.8-112.5% from 9 kinds of samples except pumpkin. The peaks detected in each sample were confirmed by GC/MS after clean-up by Florisil column chromatography. Triadimefon was eluted with 15% ethyl acetate/hexane and the others were eluted with 30% ethyl acetate/hexane from the Florisil column. Triadimefon (0.41-1.29ppm) and triadimenol (0.22-1.03ppm) were found in all of 6 pineapple skin parts and bitertanol (0.27-0.95ppm) was found in 5 banana skin parts (total 7 samples), but they were not detected in the edible parts of pineapple or banana. Detection limits of the 8 fungicides by the proposed method were 0.01ppm in the samples.

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The relationship between chemical structures of 21 kinds of pyrazole derivatives and their fungistatic activity towards Aspergillus niger was investigated by the agar plate filter paper disc method. The influence of pH upon the fungistatic activity of the compounds was tested at pH 3.7. 5.2 and 7.0. The inhibition of fungal growth was estimated in terms of initial strength of activity (IS) and its durability. The IS value of 4-chloro-m-cresol (1) obtained on incubation at pH 5.2 for 3 days was defined as 100. The durability was estimated as the period required for the initial inhibition zone to disappear under continuous incubation.
Pyrazole (2) itself showed no fungistatic activity and the compounds substituted with a methyl-, carboxy-, ethyloxycarbonyl-, hydrazinocarbonyl-, hydroxymethyl-, hydroxy-, nitroso-, amino-, acetamino- or diazo-group were in effective at any pH. On the other hand, the compounds bearing a phenyl or sulfur group such as 3-methyl-5-phenylpyrazole (11), 3, 5-dimethyl-4-phenylpyrazole (21), 3-amidinothiomethyl-5-methylpyrazole dihydrochloride (13), 3-methyl-5-pyrazoylmethyl-N, N-dimethyldithiocarbamate (14) and 3, 5-dimethyl-4-α-thiophenylpyrazole (22) showed fungistatic activity. Their IS values were inferior to that of 1, but the durabilities, except 13, were the same as or somewhat superior to that of 1. However, 3, 5-diphenylpyrazole (12), in which the 3-methyl group of 11 was replaced by a phenyl group, and bis (3-methyl-5-pyrazoylmethyl) disulfide (15), which was obtained by hydrolysis or hydrogenation followed by oxidation of 13 or 14, showed complete loss of activity.

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A simple head-space GC method was developed for the simultaneous determination of 7 organic solvents in natural color preparations. Acceptable limits of organic solvents in natural colors are set by the FDA.
Color preparations were measured in vials, to which water and sodium chloride were added. The vials were tightly capped and kept at 50°C for 1 hour in a water bath, followed by injection of 1ml of the vapor phase in the vial into the GC column. A packed column, a G-column and a capillary column were used for the separations. The standard addition method was used for the determination.
Among 35 samples, methanol in 20, acetone in 3 and isopropanol in 1 exceeded the limits set by the FDA.

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A determination method by HPLC for starting materials [sulfanilic acid (SA), G-salt (GS), R-salt (RS), Schaeffer's salt (SS)], intermediates [6, 6′-oxybis(2-naphthalenesulfonic acid) (DONS), 4, 4′-(diazoamino)-dibenzenesulfonic acid (DAADBSA)] and subsidiary colors [3-hydroxy-4-[(4-sulfophenyl)azo]-2, 7-naphthalenedisulfonic acid (RS-SA), 4-[(2-hydroxy-1-naphthalenyl)azo] benzenesulfonic acid (2N-SA), 6-hydroxy-5-(phenylazo)2-naphthalenesulfonic acid (SS-AN)] in sunset yellow FCF was developed. The following conditions were used for analysis: column, Inertsil ODS-2 (4.6mm i. d.×250mm); solvent, gradient elution system of 0.02M ammonium acetate and 40v/v% acetonitrile in 0.02M ammonium acetate; detection, SA, GS, RS, SS and DONS at 232nm, DAADBSA at 358nm and subsidiary colors at 482nm.
Recoveries of each impurity from sunset yellow FCF averaged 99.4-102.2%. Sixteen samples of commercial sunset yellow FCF in Japan were examined, with the following results: SA, N. D. -0.170%; GS, N. D. -0.080%; RS, N. D. -0.050%; SS, N. D. -0.281%; DONS, N. D. -0.250%; DAADBSA, N. D. -0.210%; RS-SA, 0.024-3.54%; mixtures of SS-AN and 2N-SA (as SS-AN); 0.015-0.360%. The detection limit was 0.05μg/g for each impurity.

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A simple and widely applicable method for the determination of cyclamate in foods by high performance liquid chromatography was developed.
The sample was dialyzed with 0.02N hydrochloric acid for 48 hours. Tetra-n-butylammonium bromide was added to the dialyzate, then the sample solution was adjusted to pH 4.0-5.0 and passed through a Mega Bond Elut C₁₈ cartridge. Cyclamate was eluted with a mixture of acetonitrile-water (3:7). Cyclamate in the eluate was converted into N, N-dichlorocyclohexylamine by reaction with sodium hypochlorite; the eluate was acidified with 50% sulfuric acid, then n-hexane and sodium hypochlorite solution were added, and the mixture was shaken to form N, N-dichlorocyclohexylamine. The n-hexane layer was shaken with sodium hydrogen carbonate solution to remove free chlorine. The N, N-dichlorocyclohexylamine in the n-hexane layer was separated on a Finepak SIL C18T-5 column with a mobile phase of methanol-water (8:2) and detected at 314nm.
The recoveries of cyclamate added at the levels of 50 and 500μg/g to various kinds of foods were 96.5-100% and 94.8-98.8%, respectively. The detection limit of cyclamate was 10μg/g. This method seems to be very well suited for routine analysis.

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A simple and rapid analytical method for the determination of n-dibutylphthalate (DBP) in imported vodka was developed. The method consists of extraction with n-hexane and determination by gas chromatography (FID). The time required for the routine analysis is about 30min per sample. Recoveries of DBP spiked at levels of 0.5, 3.0 and 5.0ppm were 98.5, 97.8 and 92.7%, respectively, and the detection limit was 0.1ppm. DBP was detected in two out of 15 vodka samples at a maximum concentration of 0.2ppm by application of this method. The presence of DBP in the vodka was confirmed by GC/MS.

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