All issues
Volume 21 (1980)
- Issue 6 Pages 425-
- Issue 5 Pages 327-
- Issue 4 Pages 243-
- Issue 3 Pages 165-
- Issue 2 Pages 113-
- Issue 1 Pages 1-
Volume 21, Issue 4
Displaying 1-12 of 12 articles from this issue
- |<
- <
- 1
- >
- >|
-
Chemical Form of Copper in Soybeans. IRyoichi TANAKA, Seisaku YOSHIDA, Takashi KASHIMOTO1980 Volume 21 Issue 4 Pages 243-246_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSAs part of a series of studies to clarify the chemical form of heavy metals in food, the interaction between Cu (and Cd) and the water-soluble fraction of soybeans was investigated.
1. Of the total Cu and Cd in soybeans, 60% of each was extracted as water-soluble supernatant by ultracentrifugation (×105, 000G).
2. The effect of pH on the extraction of the water-soluble fraction was studied. The amounts of Cu and Cd extracted at pH 4 or 5 were minimal. At pH 4 or 5, the amount of total nitrogen and the absorbance at 280nm were also minimum. This suggests that Cu and Cd may bind to a protein (s) which precipitates at its isoelectric point, pH 4 or 5.
3. Ultrafiltration of the water-soluble fraction was carried out. Approximately 90% of Cd in the water-soluble fraction was retained in the highest molecular weight fraction (m. w. greater than 40, 000). However, Cu was found in various molecular weight fractions (ca. 21% in m. w. greater than 40, 000, ca. 28% in m. w. 40, 000-10, 000 and ca. 50% in m. w. less than 10, 000).View full abstractDownload PDF (523K) -
Chemical Form of Copper in Soybeans. IISeisaku YOSHIDA, Ryoichi TANAKA, Takashi KASHIMOTO1980 Volume 21 Issue 4 Pages 247-251_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSCopper binding components in soybeans were extracted with buffer solution and separated by gel filtration.
1. 60% of Cu in soybeans was extracted with 0.01M Tris-hydrochloric acid buffer solution (pH 7.4). The protein content of the crude extract was approximately 63%.
2. The crude extract was characterized by gel filtration on Sephadex G-50. It was separated into two fractions (F-I, m. w.>ca. 10, 000 and F-II, m. w.<ca. 10, 000). F-I contained 20ppm Cu and 80-90% protein, while F-II contained 24ppm Cu and ca. 1% protein.
3. F-I was treated with enzymes. No change was found in the gel filtration profile of F-I on Sephadex G-50 after treatment with trypsin or α-amylase.
4. The binding capacity of F-I to Cu was also determined. When Cu was added in batches to F-I, the amount of bound Cu increased with the amount added. When 80μg of Cu was added to 20mg of F-I, the concentration of Cu in F-I increased over 80 times (1, 700ppm) from the original level (20ppm).
5. Cu in F-II was eluted together with nitrogen-containing material, which gave a positive ninhydrin reaction. There may be an interaction between Cu and peptides in F-II.View full abstractDownload PDF (581K) -
Masaru KOMAKI, Norihiko MATSUDA, Keiko MATSUNAWA1980 Volume 21 Issue 4 Pages 252-259_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSSpore counting media were compared for effect on the recovery of non-heat-treated and heat-treated spores of Clostridium botulinum and C. sporogenes. The spore count obtained with each of eight kinds of media was compared with that recovered with pork pea infusion agar (PPI). No difference was observed among the media in the recovery count of non-heat-treated spores. With heat-treated spores, however, the spore count recovered with yeast extract agar was largest, and was comparable to that recovered with PPI.
As regards reducing agent added to the recovery medium, no significant difference was observed between sodium thioglycollate and L-cysteine monohydrochloride. No inhibitory effect was observed when the reducing agent was added to the medium before autoclaving.View full abstractDownload PDF (761K) -
Midori NAKANO, Yoko KUBOKURA, Masuo OGAWA1980 Volume 21 Issue 4 Pages 260-265_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSMethods of culture for bacteria contained in commercial vacuum-packed sliced ham and sausage were studied, and a survey was conducted to clarify the actual state of bacterial contamination of these meat products. The results obtained can be summarized as follows.
1) Studies on methods of culture: The bacterial count obtained by incubation at 7°C was about ten to fifty times higher than that obtained by incubation at 37°C up to 3 weeks after packaging. This difference decreased later. There was no significant difference in bacterial count between aerobic and anaerobic culture, regardless of the temperature of incubation. Differences in culture method did not produce large difference in the detected bacterial flora of the meat products, in which Lactobacillus and Streptococcus were predominant. Both genera could also be grown in aerobic culture. Obligate anaerobic bacteria could be grown only in anaerobic culture incubated at 37°C, but in any case were not predominant.
2) Actual state of bacterial contamination: The highest bacterial count was obtained from aerobic culture on trypicase soy agar medium incubated at 7°C, among all the methods examined. The count was more than 50, 000per gram in 62.5%, more than 106 in 53.0%, more than 107 in 40.0%, and more than 108 in 9.0% of the samples taken from vacuum-packed sliced ham and sausage immediately after purchase. The count exceeded 105 (on average) within 7 days after packaging. It is urgently necessary to clarify the reason for the bacterial contamination of these meat products from a foodhygienic point of view.View full abstractDownload PDF (853K) -
Kunihiro SHINAGAWA, Nobuharu KUNITA, Takashi ONAKA, Niro TAKEMASA1980 Volume 21 Issue 4 Pages 266-272
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSAnti B. cereus H sera of 19 serotypes were prepared with 18 strains of B. cereus supplied by Dr. Gilbert and an additional SH-1 strain isolated from an outbreak of B. cereus food poisoning by the method of Taylor and Gilbert. The titers of Anti H sera ranged from 3, 200 to 12, 800. Some of these sera cross-agglutinated with heterologous antigens, but mono-specific H sera were prepared by absorption.
In 11 of 13 “vomiting type” outbreaks incriminated foodstuffs or clinical specimens or both yielded H-serotype 1 only. The other 2 outbreaks yielded serotypes 3 and SH-1. Two “diarrheal type” outbreaks yielded serotype 8 only. Of 140 isolates, 98 (70.0%) were serotype 1, 20 were serotype 8, 11 were serotype SH-1, 6 were serotype 3, and 5 (3.6%) were not typable (NT). In all, 135 of the 140 (96.4%) strains isolated from these episodes were typable. Of 10 food poisoning outbreaks involving not only B. cereus but also S. aureus, one yielded serotype 1 and one yielded serotype 3, while the other 8 each yielded two or three serotypes, 1+SH-1, 1+NT, 1+SH-1+NT, or NT alone. Of 70 isolates, 21 (30.0%) were serotype 1, 8 were serotype 3, 4 were serotype SH-1 and the other 37 (52.9%) were NT.
Of 115 isolates from cooked rice, 29 (25.2%) were serotype 1, 10 were serotype 8, 8 were SH-1, 6 were serotype 12, and 44 (38.3%) were NT; the others were serotype 3, 5, 9, 14, 16, or 18. Of 55 isolates from raw rice, 7 (12.7%) were serotype 7, 4 were serotype SH-1, 2 were serotype 1, one was serotype 8 and the other 41 (74.5%) were NT.
B. cereus was isolated from 65 of 433 (15.0%) samples of feces of healthy food handlers and school children; of these 65 isolates, 10 (15.4%) were serotype 1, 44 (67.7%) were NT, and the others were serotype SH-1, 8, 5, 12, or 14.View full abstractDownload PDF (938K) -
Nagao HAYASHI, Yohko TERAOKA, Hidemasa KODAKA, Mineko USHIJIMA, Akio T ...1980 Volume 21 Issue 4 Pages 273-282_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSThe formation of nitrosodimethylamine (NDMA) from dimethylamine (DMA) and sodium nitrate in the stomach of monkeys was investigated.
Five monkeys maintained on commercial monkey diet were force-fed with 20ml/kg of brain heart infusion broth containing 500ppm of DMA and 1200ppm of sodium nitrate. Three monkeys, used as control animals, were starved for one day before the force-feeding with the two compounds. The concentrations of NO2- and NDMA, the pH and the types of microorganisms in the sampled stomach contents were chemically and microbiologically determined at 0, 0.5, 1, 3, 5 and 7 hours after the administration of DMA and sodium nitrate. The blood concentration of NDMA was also measured.
The results were as follows:
1) After the administration of DMA and sodium nitrate, the peak concentrations of NO2- and NDMA in stomach contents of the three one-day starved monkeys were 2.7, 89 and 16.2ppm, and 41.1, 144.4 and 5.4ppb, respectively, while the peaks of the two compounds in the normal diet monkeys were 75.6, 69.9, 5.7, 1.0 and 201.5ppm of NO2- and 833.6, 63.9, 6.1, not detected and 4.7ppb of NDMA. However, NDMA was not detected (detection limit 0.2ng) in the blood of any monkey investigated.
2) The good NDMA converter monkeys generally had a higher pH value of the stomach contents than the poor converter monkeys.
3) No remarkable variation of microbial counts was observed in the stomach contents of the monkeys tested.View full abstractDownload PDF (1341K) -
Masakazu TSUTSUMI, Tamaki NARITA, Asao MATSUOKA, Tadao WATANABE1980 Volume 21 Issue 4 Pages 283-287_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSA halotolerant bacterium, Staphylococcus aureus IFO 3060, can grow over a wide range of sodium chloride concentrations (0-15%), but the addition of cholate to a medium containing sodium chloride resulted in a decrease of the sodium chloride tolerance of the bacterium.
A decrease of salt tolerance to some inorganic salts, lithium chloride, lithium sulfate, potassium chloride, potassium sulfate and sodium sulfate, but not potassium phosphate monobasic or sodium phosphate monobasic, was also caused by cholate. The action of these salts in the presence of cholate may be due to the anions, Cl- and SO42- (but not PO43-), rather than the cations, Li+, K+, and Na+.
Though some detergents in the presence of sodium chloride led to a decrease of the salt tolerance, the effect was not a general one, and therefore may not be ascribable to the surfaceactive properties of the detergents.
Cholate accelerated the release of Mg2+, carbohydrates, proteins and UV-absorbing substances from the cells in the presence of sodium chloride, but no release of lipids was observed.
From the results of the previous and this report, it appears that the synergistic action of salts and cholate occurs on the cell envelope, probably at the cell wall layer.View full abstractDownload PDF (658K) -
Ayako YOSHIDA, Masami IMAIDA1980 Volume 21 Issue 4 Pages 288-293_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSThe formation of formaldehyde (FA) in shrimps which were bleached with sulfite solution was investigated.
1. Approximately 300ppm of FA was detected in shrimps when they were bleached with 4.5% sulfite solution. FA was identified by Thin layer chromatography (TLC) as the dinitrophenylhydrazone and by IR spectrometry as methylenebisdimedone.
The amount of FA formed in bleached shrimps increased in proportion to the sulfite concentration.
2. The following data suggest that FA in shrimps was formed from endogeneous trimethylamine oxide (TMO) upon treatment with sulfite. When TMO in a water dialysate of shrimps was fractionated by TLC, FA was detected in the TMO fraction on treatment with sulfite. When sulfite solution was added stepwise to the water dialysate of shrimps, the amount of FA formed increased with the amount of sulfite added, and the amount of TMO in the dialysate decreased correspondingly.View full abstractDownload PDF (646K) -
Shinjiro HORI, Takashi KASHIMOTO, Nobuharu KUNITA1980 Volume 21 Issue 4 Pages 294-300_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSRats were given a single oral dose of 44mg of polychlorinated quaterphenyls (PCQ) per rat, or repeated oral doses of 1.26mg of PCQ/rat/day for 10 days. After a single oral dose of 44mg/rat, PCQ was excreted into the feces throughout the experimental period. The cumulative amount of PCQ in the feces in 6 days reached 97% of the total dose. PCQ, however, were hardly excreted into the urine. Six days after administration, approximately 2.3% of the total dose was present in the rat tissues. The liver contained the highest concentration, and approximately 50% of PCQ loaded in the whole body was found in the liver.
Following repeated oral doses of 1.26mg/rat/day for 10 days, the PCQ concentration 1 day after the final administration of PCQ was highest (34.1ppm) in the liver, followed by the adipose tissue (5.1ppm)>kidney>lung>heart>spleen>thymus>brain. After 50 days, adipose tissues contained the highest concentration (1.3ppm), followed by the liver (1.1ppm). The blood showed the lowest concentration (0.04ppm). The biological halflives of PCQ in rat tissues ranged from 14.1 days in liver to 41.3 days in adipose tissue.
The components of the residual PCQ differed between adipose tissue and liver. That is to say, more highly chlorinated PCQ was observed in the liver compared with that in the adipose tissue.View full abstractDownload PDF (890K) -
Shunjiro OGAWA, Hideyo SUZUKI, Yasuhide TONOGAI, Yoshio ITO, Masahiro ...1980 Volume 21 Issue 4 Pages 301-306_1
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSFour extraction-cleanup procedures, i. e., liquid-liquid extraction using ether (Method A), steam distillation (Method B), modified steam distillation (Method C) and alkaline hydrolysis (Method D), were tested for the gas-liquid chromatographic determination of benzoic acid in Korean ginseng tea and dried Chinese bamboo shoots. The lowest values were obtained by Method A. Those obtained by Method B were a little higher while the results with Method C increased with increase in the volume of the distillate. The highest values were obtained by Method D, the results being 5.1-32.6 times larger than those obtained by Method A. It is presumed that only free benzoic acid is extracted by Method A, while both free benzoic acid and combined benzoate could be extracted by Method D. The results of Methods B and C indicate that a part of the combined benzoate was decomposed into free benzoic acid during steam distillation. Since artificially added benzoic acid as well as its sodium salt would be present in the free form in these foods while most of the naturally occurring benzoates would be in combined form, it is recommended to apply both Methods A and D for the differentiation of artificially added benzoic acid and benzoate from naturally occurring food ingredients. Combined benzoate was provisionally calculated by subtracting the value obtained by Method A from that obtained by Method D. The absence of free benzoic acid or benzoate in food shows that these substances have not been artificially added. Steam distillation methods seem to be inappropriate, as mentioned above.View full abstractDownload PDF (707K) -
Masao MATSUMOTO, Yukinori KAGOSHIMA, Misao HARUTA1980 Volume 21 Issue 4 Pages 307-311
Published: August 05, 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESS -
1980 Volume 21 Issue 4 Pages 323
Published: 1980
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSDownload PDF (37K)
- |<
- <
- 1
- >
- >|