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Volume 12 (1971)
- Issue 6 Pages 423-
- Issue 5 Pages 349-
- Issue 4 Pages 267-
- Issue 3 Pages 149-
- Issue 2 Pages 75-
- Issue 1 Pages 1-
Volume 12, Issue 3
Displaying 1-13 of 13 articles from this issue
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Morizo ISHIDATE1971 Volume 12 Issue 3 Pages 149-151
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSDownload PDF (548K) -
Reaction of Organomercuric Compounds with Plant TissuesMitsuharu TAKEDA, Kimiaki ISOBE, Toshiro NIGO, Hiroya TANABE, Iwao KAW ...1971 Volume 12 Issue 3 Pages 152-155
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSFor the purpose to elucidate the type of mercury compounds present in agricultural products treated with organomercuric fungicides, behavior of phenylmercuric acetate and methylmercuric chloride within several kinds of young plants was studied.
Both compounds were found to be decomposed, to some extent, to inorganic mercuric compound. It was shown by thin-layer chromatography in cooperation with X-ray fluorecence analysis that phenylmercuric compound was present in rice bran.View full abstractDownload PDF (772K) -
Effect of Thiol Compounds on Decomposition of Organomercuric CompoundsKimiaki ISOBE, Mitsuharu TAKEDA, Hiroya TANABE, Iwao KAWASHIRO1971 Volume 12 Issue 3 Pages 156-159
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSDecomposition mechanism of organomercuric fungicides in plants were studied from the pure chemical point of view.
Thiol compounds such as cysteine, glutathione and dihydrothioctic acid were found to decompose organomercuric compounds to inorganic one.
Mechanism of the reactions of thiols with phenylmercuric and alkylmercuric compounds seemed to be different from each other.View full abstractDownload PDF (579K) -
Studies on the Decomposition of Organomercuric Compounds in Wheat RootsMitsuharu TAKEDA, Kimiaki ISOBE1971 Volume 12 Issue 3 Pages 160-163
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSDecomposition mechanism of organomercuric fungicides in plants were studied from biochemical point of view.
Phenyl- and alkylmercuric compounds were shown to be decomposed rapidly but with lag time, in the presence of tissue cultured wheat root.
Pretreated root with an organomercuric compound reacts with the same reagent without lag time but not with other kinds of organomercuric compounds.View full abstractDownload PDF (568K) -
Yataro KOKUBO, Fujio UMEKI, Misao HARUTA1971 Volume 12 Issue 3 Pages 164-169
Published: June 05, 1971
Released on J-STAGE: July 27, 2010
JOURNAL FREE ACCESSMicrobiological studies were made on the muscle tissue of 10 swine obtained at an abatoir. Serial psychrotrophic bacterial counts were made at regular intervals on the specimens kept at 5 and 10°C for a period of 10 days. The methods adopted for the enumeration of psychrotrophic organisms were those widely used by the dairy microbiologists, and the determination of proteolytic and lipolytic activities of the isolates were made by the use of milk agar and Crossley agar plates, respectively.
The results obtained are summarized as follows:
1) Psychrotrophic bacterial counts obtained by the use of several different determination methods agreed well one another.
2) Serial psychrotrophic bacterial counts in the specimens had indicated the gradual propagation of the organisms at 5°C, i. e., the counts reached at the order of 108 organisms per gram of meat after 7 days of the storage, however, the meat stored at 10°C for 3 days was found to have already involved about 109 organisms in one gram of sample, and the increase in pH value and rotten odors were also observed.
3) About 70% of the initial isolates of the meat were comprised in gram-negative bacteria, such as Pseudomonas, Flavobacterium, Achromobacter and others, however, after the 7 days of storage at 5°C, more than 90% of the isolates were found to have been replaced by Pseudomonas.
4) Most of the initial isolates grew well between 10-35°C. However, gram-negative strains tended to grow better at or below 30°C and gram-positive strains at or above 35°C. Most of Pseudomonas isolated from the meat stored at 5°C grew well between 0-30°C, but not at 35°C.
5) About 25% of the psychrotrophic isolates manifested proteolytic activities. On the other hand, about 31% of the isolates exhibited weak lipolytic activities, while 14% showed both proteolytic and lipolytic activitiesView full abstractDownload PDF (1165K) -
In vitro and in vivo Formation of DimethylnitrosamineAyako SAKAI, Akio TANIMURA1971 Volume 12 Issue 3 Pages 170-176
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSBy the addition of nitrite as color fixative or preservative to marine fishes or fish roes which contain in high concentration of secondary amines, such as dimethylamine or diethylamine, the formation of nitrosamine in foods have to be presumed. The conditions in which dimethylnitrosamine was produced in vitro from sodium nitrite and dimethylamine hydrochloride were studied and it was found that the optimum pH for the production of dimethylnitrosamine in buffer solutions was near 3.6. Thirty minutes after oral dosage to rabbits, 5mg of dimethylnitrosamine was detected in stomach contents when 1, 000mg of sodium nitrite and 500mg of dimethylamine hydrochloride were administered. From the results of these experiments, the possibility of the formation of nitrosamines in foods was discussed which might occur in human stomach by the uptake of nitrite as food additive and when the foods which contain large quantities of nitrite and secondary amines were administered.View full abstractDownload PDF (1241K) -
Colorimetric Determination of Secondary Amines and NitrosaminesYoshio ITO, Akio TANIMURA1971 Volume 12 Issue 3 Pages 177-184
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSThe precursors of nitrosamines which has been known as potent carcinogenic substance, were found as nitrite and secondary amines by the discovery during the storage of fishmeal preserved with nitrite. Although nitrite is used in foods as color fixative in many countries, it is also detected in natural products such as vegetables, fruits and other many kinds of foods. Secondary amines, the other precursor are detected in fishes especially in marine fishes and fish roes, but few data concerning the distribution of secondary amines in foods were reported. For the purpose of investigating on the toxicity of nitrosamines in foods, the distribution of secondary amines in common daily foods is important and it is necessary to establish a determination method of secondary amine. The authors modified the naphthylamine colorimetric method reported by Uno, and succeeded in obtaining good recovery and sensitivity.View full abstractDownload PDF (1235K) -
Extraction and Identification of Secondary Amines in FoodsYoshio ITO, Hiroko SAKUTA, Shigetoshi YOKOTA, Ikuko AYUKAWA, Akio TANI ...1971 Volume 12 Issue 3 Pages 185-191
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSIt is necessary to research the distribution of secondary amines in foods which is one of the precursors of carcinogenic nitrosamines. In this report, rapid and not complicated extraction method of secondary amines from foods was described and over 98.6% of recovery was obtained by this method. For the identification of secondary amines in foods, thinlayer chromatography has been commonly used. But the chromatograms were sometimes disturbed with contaminated primary amines, ammonium salts or the other substances. To exclude the contaminants secondary amines were converted into nitroso compounds, purified, and carried out by thin-layer chromatography. By this procedure secondary amines extracted from foods could be clearly identified on the plate.View full abstractDownload PDF (919K) -
Distribution of Secondary Amines in FoodsTaro KAWAMURA, Keiichi SAKAI, Fumio MIYAZAWA, Hiroshi WADA, Yoshio ITO ...1971 Volume 12 Issue 3 Pages 192-197
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSIt is presumed that secondary amines contained in various foods were combined with nitrite which was added to the foods as the color fixative to form the carcinogenic nitroso compounds.
And the possibility also must be discussed whether nitroso compounds were produced in human stomach when the foods whcih contained of high concentrations of secondary amines and nitrite respectively were successively administered, the animal experiments by use of rabbits being described in the first report of this series. Distribution and amounts of secondary amines in a few kinds of foods was already reported by some authors, though not in detail. In this report, distribution and amounts of secondary amines in foods, especially in Japanese proper foods, and the results of analyses of nitrosamines in foods were also described. Fishes, marine fishes and fish roes contained large quantities of secondary amines, i. s. dimethylamine and diethylamine, and the amounts in roasted fishes increased markedly. The amounts of secondary amines in meats, even in roasted meats, were trace, and nitrosamines were not detected in a kinds of foods by thin-layer chromatography.View full abstractDownload PDF (899K) -
Susumu HORIE, Shiro SATO, Michiko MIYANABE1971 Volume 12 Issue 3 Pages 198-202
Published: June 05, 1971
Released on J-STAGE: July 27, 2010
JOURNAL FREE ACCESSAzide yeast dextrose-ethyl violet azide citrate broth method (AYD-EAC) for enterococcal test, reported by Horie in 1960, was reviewed and an improved method, AC (37°C) -AC (45°C), was developed in this work.
In the new method, azide citrate medium (AC, polypepton, 20g; yeast extract, 5g; dextrose, 5g; Na-citrate·2H2O, 10g; NaCl, 5g; K2HPO4, 4g; KH2PO4, 1.5g; NaN3, 0.25g; distilled water, 1, 000ml) was employed both in presumptive and confirmatory test, respectively. Although the composition of AC medium resembled closely to that of EAC medium used in original method, ethyl violet was not used in the new medium.
AC medium tubes inoculated with serial dilutions of the samples were incubated at 37°C for 48±3 hours. Tubes showing turbidity were transfered to fresh tubes of AC medium, using a wire loop (3mm in diameter). After the tubes were incubated for 48±3 hours at 45°C, tubes showing turbidity were considered positive confirmatory test.
Using AYD-AC and AC-AC method, MPN values of enterococci in 27 samples of various contaminated waters, raw oyster and frozen foods were determined. It was shown that although MPN values obtained by both methods were comparable, AC medium gave less false positive tubes than AYD medium in presumptive test. Of 188 tubes recorded as positive in confirmatory test of AC-AC method, 187 were found to contain Gram-positive cocci, in pairs or short chains, which grew in 6.5% NaCl containing glucose broth and showed negative catalase test.
It was known that AC-AC method was highly specific for the determination of entero-cocci in samples, such as contaminated waters or foods, which contain heterogeneous bacterial flora.View full abstractDownload PDF (786K) -
Constitution of Bacterial Flora in Stored MilkMichio HAMAMOTO, Toshiro KANAUCHI1971 Volume 12 Issue 3 Pages 203-208
Published: June 05, 1971
Released on J-STAGE: July 27, 2010
JOURNAL FREE ACCESSComposite samples of bottled milk were stored at 0-37°C and changes in bacterial flora were observed.
Before the storage, 469 isolates as after U.H.T. sterilization contaminants were obtained from the 1.5L of the milk sample. These strains were divided into 40 types and 72% of the contaminants were regarded as psychrotroph.
Outline changes of bacterial flora during the storage were observed by the changes in rates of standard plate counts and psychrotrophic plate counts, designated by Standard Methods, Eddy or Ingraham, to the viable cell counts.
Bacterial flora observed in the early stages of storage were distinctly different from those before the storage and invariable constitution was found in each stored sample when the viable cell counts were relatively small in number.
In the latter stages of storage, psychrotroph designated by Ingraham in the milk sample stored at 0°C, psychrotroph designated by Eddy in the samples stored at 3°C or 5°C and psychrotroph designated by Standard Methods in the samples stored at 7°C or 10°C were enumerated equal in number to the viable cell counts, and only 7 types of psychrotroph were demonstrated from the samples stored at 0-10°C. In the relation to the storage temperature, psychrotrophs having lower minimum growth temperature were not always dominant at the range of these low temperature, and the rates of these psychrotrophs decreased stepwise at the higher temperature.View full abstractDownload PDF (1182K) -
An Attempt to Estimate Shelf-Life of Market MilkMichio HAMAMOTO, Toshiro KANAUCHI1971 Volume 12 Issue 3 Pages 209-215
Published: June 05, 1971
Released on J-STAGE: July 27, 2010
JOURNAL FREE ACCESSMeasurements were made on the rates of multiplying of psychrotrophic strains and bacterial growth in the stored milk, and the influences of storage temperature, psychrotrophic species and level of contamination on the bacteriological shelf-life of market milk were analysed.
On the multiplying of psychrotrophs, marked differences in the generation time were observed among the strains at the low temperature, where little differences were observed above 15°C. And the logarithmic growth rates (reciprocal of generation time) were shown as parabolic functions of incubation temperature below 27°C, and the growth lags were assumed as constants depending on the strains.
In the composite samples of bottled milk, similar relation was found between the doubling rate of contaminants and the storage temperature at the range of 3-32°C, but the growth lag estimated from the initial level of viable cell counts was not constant. But the variations in growth lags estimated by the initial levels of bacteria that grew dominantly in each stored temperature were less than those of viable cell counts. And the doubling rates for the bacterial growth in composite samples of bottled milk were almost equal to the rates of rapidly grown psychrotroph in the low temperature.
From the results of these analyses, trial estimations were made on shelf-life of market milk, assuming 5×104/ml as the level of practical significance, and it was considered that the storage temperature was most important, because the differences in shelf-life were arisen only in low temperature by the differences of species or levels of contamination. And it was found that the equal response of estimates arose from the difference of 1°C in storage temperature or the 10-fold difference in the initial level of contaminants. And the estimates of shelf-life suggested that undesirable changes would not occur within 3 days at 10°C, and 5 days of bacteriological shelf-life would be expected below 5°C.View full abstractDownload PDF (1372K) -
Yoshiko SHIRAISHI, Yoshiaki KUZUHARA, Yoneji SAKAGAMI1971 Volume 12 Issue 3 Pages 216-219
Published: June 05, 1971
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSDownload PDF (622K)
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