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Volume 28 (1987)
- Issue 6 Pages 427-
- Issue 5 Pages 311-
- Issue 4 Pages 219-
- Issue 3 Pages 159-
- Issue 2 Pages 109-
- Issue 1 Pages 1-
Volume 28, Issue 6
Displaying 1-12 of 12 articles from this issue
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Yasuhide TONOGAI, Yumiko NAKAMURA, Sumiko TSUJI, Yoshio ITO1987 Volume 28 Issue 6 Pages 427-435_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSMethods for the detection and determination of polysorbate in powdered soup from instant noodles by two colorimetry procedures using cobalt-thiocyanate and Dragendorff reagents have been developed.
Suitable conditions for thin layer chromatography of polysorbate were as follows: adsorbent, silica gel; developing solvent, dichloromethane-methanol-acetone-water (55:20:15:4) mixture; color development, Dragendorff reagent.
Purification of the extract from a sample was carried out by chromatography on a silica gel column and elution with dichloromethane-methanol (2:1) mixture after washing with ethyl acetate.
Dragendorff reagent was examined for colorimetry of polysorbate as well as cobalt-thiocyanate reagent. The range of calibration at the wavelength of 500nm was 10-50μg/ml of polysorbate. The sensitivity was 5 times higher than that with cobalt-thiocyanate.
Polysorbate was added to the sample at the 200ppm level and determined by the use of both colorimetry procedures; the recoveries ranged between 94.5 and 97.0%. Contents of polysorbate in domestic and imported samples were determined and 100-345ppm of polysorbate was found in imported samples by the proposed method.View full abstractDownload PDF (881K) -
Sachie IKEGAMI, Fumie TSUCHIHASHI, Mitsunori OHNO, Eiichi NISHIDE1987 Volume 28 Issue 6 Pages 436-444_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSThe study was performed to clarify the biological effects of chlorinated benzenes with different degrees of chlorination and different substituents. One series from monochlorobenzene to hexachlorobenzene was used to study the effect of the number of chlorine atoms. The second series was composed of p-amino-, hydroxy-, nitro- and methyl-chlorobenzene. Sprague Dawley male rats aged 4 weeks were fed diets containing the chlorinated benzenes at the level of 500ppm for 2 weeks.
When the number of chlorine atoms in the benzene ring is over 4, the weight of the liver, lipid components in the liver and serum (total lipid, phospholipid and cholesterol), cytochrome P-450 and cytochrome c reductase significantly increased. However, the intensity of the biological effect was not always related to the number of chlorine atoms; the parameters were more markedly increased by pentachlorobenzene administration than by hexachlorobenzene administration.
Vitamin A contents in the liver and serum were decreased by feeding of chlorinated benzenes, particularly pentachlorobenzene. Lipid peroxide in the liver was significantly elevated by pentachlorobenzene and monochlorobenzene administration, being accompanied by an increase of triglyceride and decreases of vitamin E and glutathione peroxidase.
On the other hand, the biological effects of aniline, phenol, nitrobenzene and toluene were not markedly enhanced by chlorination.View full abstractDownload PDF (1090K) -
Sumiko TSUJI, Kôhei ISHIDA, Yumiko NAKAMURA, Yasuhide Tonogai, H ...1987 Volume 28 Issue 6 Pages 445-452_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSIn the determination of hydrogen peroxide in soft drinks containing ascorbic acid by using the oxygen electrode method, it was necessary to adjust the sample to the optimum pH for catalase with phosphate buffer. Various methods for mixing the sample with phosphate buffer were studied with 11 kinds of commercial soft drinks.
Two of those methods were as follows: (i) the sample was put in the sample cell of the apparatus with the oxygen electrode after purging dissolved oxygen from the phosphate buffer; (ii) the sample was mixed with phosphate buffer and dissolved oxygen was purged from this sample solution in the cell. The released oxygen was then measured after addition of catalase. By the former method, hydrogen peroxide was not found in any samples. The latter gave hydrogen peroxide contents of 0.2-4.7μg/ml. The reason for this was that hydrogen peroxide was formed by oxidation of ascorbic acid before the addition of catalase during mixing of the sample with phosphate buffer.View full abstractDownload PDF (873K) -
Sadao UCHIYAMA, Yukio SAITO1987 Volume 28 Issue 6 Pages 453-460_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSThe binding potential of ochratoxin A (Oct. A), a carcinogenic mycotoxin detected in cereals and proteinous products, to animal tissue and serum proteins in vitro was investigated to get basic information on its toxicity. The relationship between the binding potential and fluorescence enhancement of Oct. A in the presence of serum albumin is also discussed. Oct. A had a high affinity to serum albumin but little affinity to soluble tissue proteins of liver and kidney in the rat as determined by electrophoretic analysis. Human serum albumin (HSA) had a much higher affinity for Oct. A than did α1-, α2-, β- and γ-globulins. The binding parameters to HSA were n=2.15±0.05 and K=6.01±0.09 (×105/M). The fluorescence enhancement of Oct. A in the presence of HSA was pH-dependent and increased from pH 4.0, reaching a maximum at pH 5.0. These data were similar to those for bovine serum albumin (BSA). The enhancement was not connected with major binding at a carboxyl group of Oct. A but probably with a weak interaction between an isocoumarin ring of Oct. A and the albumin protein.View full abstractDownload PDF (2843K) -
Ikuo SUDA, Tadao WATANABE, Masakazu TSUTSUMI1987 Volume 28 Issue 6 Pages 461-465_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSThe correlation among the sensitivity to sodium chloride or cholate, the variation of succinate dehydrogenase activity caused by cholate and the protective effect of the outer membrane against the antibacterial action of cholate was investigated using E. coli JE 1011 and its mutants.
These bacteria were classified into cholate-sensitive and cholate-resistant strains. The cholate-sensitive strains had a high tolerance for sodium chloride, but the salt tolerance was markedly weakened by cholate. On the other hand, the salt tolerance of the cholate-resistant strains was relatively low, but was not weakened by cholate.
Succinate dehydrogenase activities of the cholate-sensitive strains were inhibited by cholate, though the activities of the cholate-resistant strains were activated by it.
The outer membrane of the cholate-resistant strains contained b-, c- and d-protein, regarded as major proteins in the membrane of E. coli, but the membrane of the cholatesensitive strains lacked one or more among these proteins. These results suggest that major proteins in the outer membrane exhibit a protective effect against the antibacterial action of cholate.View full abstractDownload PDF (2992K) -
Yasutaka KATSUKI, Shigeru MATSUMOTO, Hideo TSUYUKI1987 Volume 28 Issue 6 Pages 466-472_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSPurified triolein (TO) and trilinolein (TL) were oxidized by introducing oxygen at 75°C into the same apparatus as employed previously. In each oxidized sample, volatile decomposition products, especially aldehydes (as the origin of rancid odor), were identified by gas chromatography mass spectrometry, comparing with the products from the corresponding fatty acid methyl-ester.
It was observed that heptane and octane as hydrocarbons, 1-heptanol and 1-octanol as alcohols, and heptanal, octanal, nonanal, decanal, 2-decenal and 2-undecenal as aldehydes were formed from TO, while pentane as a hydrocarbon and hexanal, heptanal, 2-heptenal, 2-octenal and 2, 4-decadienal as aldehydes were obtained from TL. The precursors of those products, the monohydroperoxides (MHP), and cleavage positions were discussed in comparison with those of methyl-esters. The formation mechanism of the above products could be explained except for heptanal from TO and 2-heptenal from TL (these were assumed to be secondary oxidation products). Further, 3-nonenal (or 2-nonenal), which was expected to be formed from TL, was not found. In the oxidation of TL, formation of 11-MHP was found in addition to 9-MHP and 13-MHP.
The relative percentages of peak area were calculated from a gas chromatogram of volatiles derived from TO, and aldehydes accounted for about 67% of the area. The odor of octanal was the strongest. In the oxidation of TL, 2, 4-decadienal accounted for 42% of the total area, and the odor of hexanal was the strongest at each stage of oxidation.View full abstractDownload PDF (742K) -
Kojun TSUNODA, Noriko INOUE, Mitsuo AOYAMA, Akihisa HASEBE1987 Volume 28 Issue 6 Pages 473-479_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSA rapid and simple analysis procedure involving a batch system using polyamide (nylon-6 powder) was devised for the detection of food colors. The food colors were extracted from food with a mixture of 1% ammonia water and ethanol (4:6). The extract was filtered, and the filtrate was diluted two or three times with water. The colors in the solution were absorbed on a small amount of polyamide (10-30mg) in acid (pH 4-5). After filtration and rinsing with hot water, the polyamide was suspended and eluted with a small quantity (about 100μl) of a mixture of 28% ammonia water and ethanol (4:6). After five min, the supernatant was used for paper chromatography and thin layer chromatography on a silica gel plate or a polyamide sheet. The solvent systems for the chromatographies were as follows: paper chromatography, butanol-ethanol-1% ammonia water (6:2:3); silica gell thin layer chromatography, ethyl acetate-ethanol-28% ammonia water (3.3:1:1) or (4.5:1:0.7); polyamide thin layer chromatography, methanol-ethanol-isoamyl alcohol-28% ammonia water (15:10:5:3). The systems containing ammonia as described above were required for separation of the food colors. Compared with the wool dyeing method, the presented method did not require evaporation of alcohol, heating for adsorption or elution of the food colors or concentration of the eluate. It is rapid, simple and precise for the detection of the food colors in various colored foods.View full abstractDownload PDF (885K) -
Shingo MIZUOCHI, Keiko YOSHIDA, Hirokazu OGIHARA, Misao HARUTA1987 Volume 28 Issue 6 Pages 480-482_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSIn 1983, Tan and his co-workers presented a plate MPN technique for estimating viable cell counts as a substitute for the traditional method. This simple system was compared with the pour plate method for the estimation of lactic acid bacterial counts in fermented milks and lactic acid bacteria drinks.
The correlation coefficients between plate MPN counts and pour plate counts in pure cultures of lactic acid bacteria, and fermented milks and lactic acid bacteria drinks were 0.983 and 0.929, respectively.
The plate MPN technique appears to be a convenient procedure for the estimation of lactic acid bacterial counts in fermented milks and lactic acid bacteria drinks.View full abstractDownload PDF (366K) -
Keiko YOSHIDA, Shingo MIZUOCHI, Misao HARUTA, Yoshikazu SIMIZU, Toshik ...1987 Volume 28 Issue 6 Pages 483-486_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSFor enumerating viable bacteria in raw milk, the Petrifilm method was compared with the standard plate count method and Breed method. 1) The correlation coefficient between Petrifilm SM counts and Breed clump counts was 0.916, and the regression line, with a slope of 1.00 and an intercept of -0.11, was close to the line of equality. 2) On average, Petrifilm SM counts were 15% lower than plate counts, but the correlation coefficient between both counts was 0.972 and the regression line, with a slope of 0.92 and an intercept of 0.60, was close to the line of equality. 3) An incubation time of 48 hours in the Petrifilm method and plate count method was better than 24 or 72 hours. 4) The personal errors in the Petrifilm method were fewer than in the other methods.View full abstractDownload PDF (439K) -
Ken-ichi NAKAYA, Akira SUGITANI, Makoto KAWAI1987 Volume 28 Issue 6 Pages 487-491_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSA sensitive and simple method for simultaneous determination of destomycin A (DM) and hygromycin B (HM) in pork by high performance liquid chromatography with a fluorescense detector was developed.
DM and HM was extracted with 10% trichloroacetic acid, and the extract was applied to an Amberlite CG-50 column (NH4 form) followed by a Dowex 1-X8 column (OH form) to obtain a test solution. A portion of the test solution was treated with o-phthalaldehyde to derivatize DM and HM. The derivatives were separated on a TSK gel ODS-120T column with methyl alcohol-water-acetonitrile (65:30:5) as the mobile phase and quantitated by fluorometry.
Recoveries of DM and HM added to pork at levels of 0.25 and 0.5μg/g and at 0.5 and 1.0unit/g were 73.8 and 82.5%, and 77.4 and 81.6%, respectively. The detection limits were 0.1μg/g for DM and 0.3unit/g for HM in the sample.View full abstractDownload PDF (508K) -
Kayoko KOBAYASHI, Masatake TOYODA, Yukio SAITO1987 Volume 28 Issue 6 Pages 492-497_1
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSA simple and rapid method for the quantitative determination of ethyl carbamate (EC) in alcoholic beverages was developed.
Twenty grams of sample was placed onto an Extrelut 20 column after the pH of the sample had been adjusted to 8.0, and the column was eluted with 70ml of dichloromethane. The eluate was mixed with 1.8ml of acetonitrile and made up to 60ml. The solution, after purification through Sep-pak Florisil, was concentrated to about 5ml using a Kuderna-Danish concentrator, then to 0.5ml with a stream of nitrogen. The test solution was alkylated with N, N-dimethylformamide dimethylacetal, purified by Extrelut column chromatography and concentrated. The derivation of EC was checked by capillary gas chromatography with a flame ionization detector.
The recovery from three kinds of alcoholic beverages spiked with EC at the level of 300ppb was 70.9-86.3%, and the detection limit was 30ppb. This is a little higher than that of our previous method, i. e., 10ppb, but the proposed method is very rapid compared with our previous method, and it took only five or six hours to analyze one sample.
By using this method, nine samples of commercial alcoholic beverages, sake, beer, shochu and sour, gin fizz, red wine, white wine, bourbon whisky and brandy were analyzed. Trace amounts of EC were detected in four samples.View full abstractDownload PDF (553K) -
Mutsuo ISHIZAKI, Seiichi UENO1987 Volume 28 Issue 6 Pages 498-501
Published: December 05, 1987
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSDownload PDF (316K)
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