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Volume 29, Issue 1
Displaying 1-10 of 10 articles from this issue
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Takafumi OHTA, Kimiko KOJIMA, Yasuko MIYAMOTO, Takashi INOUE, Shoji TA ...1988 Volume 29 Issue 1 Pages 1-6_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSConvenient spectrophotometric methods for analysis and characterization of N-nitroso compounds (NC) formed in foods by nitrite treatment were developed.
Foods were homogenized with water, supplemented with nitrite, adjusted to pH 3, and incubated at 37°C for 1hr. NC formed were extracted effectively with ethyl acetate after addition of phosphoric acid and sodium sulfate, and analyzed by using hydrogen bromide/acetic acid- and hydrogen chloride/acetic acid-Griess reagents. Based on these measurements, NC were classified into three groups, those whose precursors have pKa values larger than about 10.7, those whose precursors have pKa values smaller than about 10.7 and larger than about 4.8, and those (SNC) whose precursors have pKa values smaller than 4.8. Nitrosamides content was calculated by subtracting the SNC content from the NC content determined by a modification of the method of Preussmann and Schaper-Druckrey.
The above methods were applied to several nitrite-treated foods. The amount of total N-nitroso compounds (TNC) formed and the proportion of NC content of each group in TNC differed greatly with different foods, indicating that the present methods are useful for characterization of NC formed in foods by nitrite treatment.View full abstractDownload PDF (756K) -
Michio SATO, Akira TANAKA, Toshie TSUCHIYA, Tsutomu YAMAHA, Shinsuke N ...1988 Volume 29 Issue 1 Pages 7-12_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSExcretion, organ distribution and metabolic fate of sodium o-phenylphenate (OPP-Na) and o-phenylphenol (OPP) were studied in male rats mainly with 14C-compounds. Both OPP-Na and OPP were rapidly excreted in the urine and feces following oral administration. About 85-90% of the dose appeared in the urine, but only 3-4% in the feces within 48hr. Biliary excretion amounted to about 27% of the dose 72hr after oral administration of OPP-Na, and was higher than that in the feces. This fact suggests that enterohepatic circulation of OPP metabolites occurs in the body. No significant retention was observed in organs and tissues on Days 1, 3 and 7 for OPP-Na, and Days 1 and 7 for OPP after dosing. Autoradiographic studies of intact rats gave the same results. The major metabolites in the urine were the conjugates of OPP after a single oral administration of OPP-Na. OPP, 2, 5-dihydroxydiphenyl (DHD) and 2-phenyl-p-benzoquinone (PBQ) in a free state were identified in the pooled urine of the rats receiving the 2% OPP-Na diets for 2 weeks. No remarkable difference was observed in excretion pattern or metabolites between OPP-Na and OPP in the single dose experiments.View full abstractDownload PDF (2139K) -
Tomoko NAGATA, Masanobu SAEKI1988 Volume 29 Issue 1 Pages 13-20_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSA high performance liquid chromatographic method (HPLC) for determination of 7 sulfonamides, clopidol, trimethoprim, ormethoprim, furazolidone, dinitolmide, pyrimethamine, ethopabate, difurazone, nicarbazin, and decoquinate, in chicken tissues was developed.
The drugs were extracted from tissues by homogenizing with warm methanol. The homogenate was centrifuged and the supernatant was evaporated to dryness. The residue was dissolved in buffer solution (pH 5.5) and partitioned with n-hexane. The buffer solution was then partitioned with chloroform. The chloroform layer was evaporated to dryness and the residue was dissolved in 85% acetonitrile and applied to an alumina column. The drugs were eluted with 85% acetonitrile and the eluate was applied to an HPLC column packed with Nucleosil 5C18.
Decoquinate was eluted with methanol-water (9:1; detected at 315nm), difurazone and nicarbazine with acetonitrile-acetic acid-water (50:0.5:50; detected at 350nm), and the other drugs with acetonitrile-acetic acid-water (14:0.5:86; detected at 270nm and at 350nm).
The average recoveries of all drugs added at the level of 0.2ppm were more than 65.5%. The detection limits of clopidol, difurazone, nicarbazin, sulfamerazine and sulfamethoxy-pyridazine were 0.03ppm, and those of the other drugs were 0.05ppm.View full abstractDownload PDF (694K) -
Yoko KAWAMURA, Eiichi KAMATA, Yukio OGAWA, Toyozo KANEKO, Sadao UCHIYA ...1988 Volume 29 Issue 1 Pages 21-25_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSThe effect of various foods on the intestinal absorption of benzo(a)pyrene (BP) was studied. Mixtures of 14C-BP and twelve kinds of foods and food components were administered orally to rats, and the radioactivity in blood was determined at intervals. Oils such as triolein and soybean oil enhanced the absorption of BP and the absorption ratios were 50.5% and 39.4%, respectively. On the other hand, water suspension, and solid foods and food components such as cellulose, lignin, bread, rice flake, starch, potato flake, spinach, katsuobushi (dried bonito) and ovalbumin suppressed the absorption of BP and the absorption ratios were 20.1% to 29.5%. Among solid foods and food components, the absorption was related to the extent of BP release from foods in vitro. The binding of BP to solid foods might be the most important factor in suppressing the intestinal absorption of BP.View full abstractDownload PDF (591K) -
Yoko KAWAMURA, Takashi UMEMURA, Masami WAKANA, Toyozo KANEKO, Sadao UC ...1988 Volume 29 Issue 1 Pages 26-31_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSThe effect of two different carriers, oil solution and water suspension, on the distribution, excretion and lymphatic absorption of benzo(a)pyrene (BP) administered orally to rats was studied. The highest amount and concentration of radioactivity were found in liver and kidney after the intestinal absorption of 14C-BP in both forms. The water suspension form gave higher concentration of BP in liver and kidney than the oil solution form and enhanced their localization. The radioactivities in lung, spleen and testis were below 0.1% and there was no significant difference between the two carriers. The main excretion route of BP in the oil solution was the bile. In the case of water suspension, the renal excretion was relatively more important. The recovery in lymph was 0.20% in the oil solution group and 0.22% in the water suspension group. The lymphatic absorption accounted for only a small portion of the intestinal absorption of BP, and there was no significant difference between the two groups. It was found that the nature of the carrier affected not only the intestinal absorption but also the distribution and excretion of BP.View full abstractDownload PDF (589K) -
Mitsuo OISHI, Eiko AMAKAWA, Tsutomu OGIWARA, Nobuo TAGUCHI, Kazuo ONIS ...1988 Volume 29 Issue 1 Pages 32-37_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSA method for determination of nicotinic acid (NA) and nicotinamide (NAA) in meat by high performance liquid chromatography (HPLC) was developed.
NA and NAA were extracted from meat with methanol and the extract was cleaned up with a Sep-pak alumina N cartridge. NAA was eluted with methanol and NA was eluted with 0.1M sodium hydrogencarbonate from the cartridge. NA and NAA in each eluate were separated on a column packed with LiChrosorb RP-18 by using methanol-acetate buffer (pH 5) containing 0.1M sodium acetate and 0.01M tetrabutylammonium hydroxide (2:10v/v%), as a mobile phase, with detection at 261nm. Recoveries of NA and NAA from ground meats spiked at levels of 0.5 and 2.0mg/100g were more than 92%. NA was detected in 24 of 155 samples of commercial ground meat at the level of 1.1-45.7mg/100g and NAA was detected in all of the samples at the level of 1.1-5.9mg/100g.
The effect of storage time on content of NA an NAA in meat at -18, 4, 10 and 25°C was examined. At 10°C, NAA content began to decrease on the 2nd day and NAA was no longer detected on the 5th day, whereas NA began to be detected on the 2nd day and its content subsequently rapidly increased. The total amount of NA and NAA in one sample was approximately constant during storage.
Based on these results, NAA in meat appears to be converted to NA during sotrage.View full abstractDownload PDF (529K) -
Masako NOSE, Ichirou HIRATA, Teruyosi ARAI, Kenji OHTA, Senzou SAKAI1988 Volume 29 Issue 1 Pages 38-46_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSAntibacterial action of Na-citrate in combination with Na-cholate was investigated on some Gram-negative bacteria involved in food poisoning and food spoilage.
Vibrio groups (V. cholerae non-01, V. fluvialis and V. parahaemolyticus) and Plesiomonas shigelloides were inhibited by 0.1 or 0.2M Na-citrate and 0.1% Na-cholate at pH 7.0, but higher amounts of both acids were required for inhibition at pH 8.0. Campylobacter jejuni and Yersinia enterocolitica were inhibited by 0.04M Na-citrate and 0.1% Na-cholate, and by 0.2M Na-citrate and 0.2% Na-cholate, respectively. Inhibition by combined Na-citrate and Na-cholate was also observed on the growth of Aeromonas hydrophila, Alcaligenes faecalis, Citrobacter freundii, Escherichia coil, Proteus vulgaris, Pseudomonas fluorescens and Serratia marcescens.
Based on the above results, the effectiveness of combinations of citric acid (as a food component) and bile acids for inhibiting the growth of food poisoning bacteria in the human intestine is discussed.View full abstractDownload PDF (822K) -
Hiroko NARITA, Yuriko SUZUKI, Kimie ASAOKA, Masami OHMURA, Kumiko HASH ...1988 Volume 29 Issue 1 Pages 47-51_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSA method to quantitate BHA and BHT by a continuous extraction method using an essential oil distilling apparatus (Shizuoka Prefecture method) was developed in collaboration with 7 research institutions by selecting salad oil, butter and dried fish as samples.
In salad oil and butter, the recoveries of BHA and BHT were 80% or more, while in dried fish, the recovery of BHA was 80% or more but that of BHT was only about 60%.
The modification of directly adding n-butyl acetate (butyl acetate method) or acetone (acetone method) improved the recovery of BHT to about 80% from dried fish. The recovery and precision in BHA determination by the butyl acetate method or the acetone method were satisfactory.View full abstractDownload PDF (419K) -
Katsuhiko IKEBE, Yukio TANAKA, Ryoichi TANAKA1988 Volume 29 Issue 1 Pages 52-57_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESS -
Akihiro TSUMURA, Kinuko HIRAMATSU, Miyako OHNISHI, Kanae TAKAHASHI1988 Volume 29 Issue 1 Pages 58-61_1
Published: February 05, 1988
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESS
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