NIPPON SUISAN GAKKAISHI
Online ISSN : 1349-998X
Print ISSN : 0021-5392
ISSN-L : 0021-5392
Volume 1, Issue 2
Displaying 1-5 of 5 articles from this issue
  • Kiyomatsu MATSUBARA(SAKAMOTO)
    1932 Volume 1 Issue 2 Pages 67-69
    Published: August 10, 1932
    Released on J-STAGE: February 29, 2008
    JOURNAL FREE ACCESS
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  • Hiroaki AIKAWA
    1932 Volume 1 Issue 2 Pages 70-74
    Published: August 10, 1932
    Released on J-STAGE: February 29, 2008
    JOURNAL FREE ACCESS
    About 30 samples were collected around the Near and the Rat Islands of the Western Aleutian Islands during the IV voyage of the Hakuhô-maru in July and August, 1928. They were disposed to me for quantitative and qualitative studies, by which the following results were obtained: (1) Quantitative distribution of plankton. Aline drawn between the Near and the Rat Islands divides the investigated area into 2 parts: one extending along the coast of the Bering Sea and the other along the Pacific coast. The former is far richly populated by plankton than the latter. The poorly populated regions are located along the eastern coast of the Near Islands, close to the southern part of the Rat Islands, and most extensively between these two islands, Densely populated regions are found between these poorly populated regions in the Pacific on one hand, and along the north-eastern part of the Near Islands and around the Rat Islands in the Bering Sea on the other. The above mentioned fact coupled with the state of isotherms and isohalines of the surface and 50-meterlayers seems to show that the surface water masses are descending into the lower layer just in the region poorly populated by plankton, thus preventing the water masses coming from the south and the north from mingling with each other in the deeper layer. On the contrary, the densely populated regions seem to lie at the places where the deeper water mass is rather upwelling or the water masses form the northe and the south are stagnant. Possibly, in the poorly populated regions the water may lack some nutrient salts, while either the mechanical accumulation by the stagnation of the water mass or the rapid growth of plankton by the abundant supply of the nutrient salts may account for regions of dense population (see text-fig. ang table B). (2) Qualitative result. The plankton in this area is rather monotonous and few in number of species (see Table A on p. 72). Chaetoceros is mainly observed in the poorly populated regin (I a-c) as well as in the fairly populated region (II a-c), and most of them are found along the Pacific coast. The densely populated region on the Pacific side has Nitzschia seriata as the representative species in addition to Thalassiothrix longissima and Coscinodiscus. The densely populated regions along the northern part of the Rat Islands (III) shows Thal. long. as the leading species. The densely populated region on the north-eastern part of the Near Islands (IV) contains prominently and abundantly Rhizosolenia and Denticula sp. Among the animal plankton, Eucalunus elongatus, Cyttarocyis Ehrenbergii and Codonellopsis morchella prevail mainly on the Pacific side, but on the contracy Calanus pulmchrus and the genus P ?? rafavella in the Bering Sea. The difference of percentage of each species, especially of plankton animals, which may be far more sensible than the phytoplankton, shows to some extent the grade of mixture of the Bering Sea water and Pacific water in the investigated area. The line between the Near and the Rat Islands divides this area into 2 regions not only quantitatively but also qualitatively. Most plankton plants of this area are common to the southern seas of the Pacific side of Japan, but is may be mentioned that these species which prevail in the Summer plankton here generally abundant among the Spring plankton in the southern seas.
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  • Yarokurô YAMAMURA
    1932 Volume 1 Issue 2 Pages 75-76
    Published: August 10, 1932
    Released on J-STAGE: February 29, 2008
    JOURNAL FREE ACCESS
    The following empirical formula is obtained between the ammonia-content at the beginning of decomposition of fish muscle, A0, and that after D-days A. A=A0eKD (Fig. 1), where K is a constant.
    The values of K are caluculated by the formula for a number of fish kinds (Tab. 1). It is shown that the value of K has a remarkable correlation with total nitrogen, N, fat, F, and water, W, contents such as: rK×X=-0.615±0.121, rK×F=-0.650±0.113 and rK×W=+0.638±0.115.
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  • Takeo OYA, Masao KIMATA
    1932 Volume 1 Issue 2 Pages 77-80
    Published: August 10, 1932
    Released on J-STAGE: February 29, 2008
    JOURNAL FREE ACCESS
    AKAMATSU found by the estimation of the increased acidity and of the inorganic phosphoric acid that Taka-phosphatase (which is contained in Taka-diastase from Aspergillus oryzae) decomposes not only the synthetical glycerin-phosphoric acid, but also the glycerin-phosphoric acid which is a decomposed product from lecithin. One of the authors measured cholin, a decomposition product of lecithin by lecithase, and inorganic phosphoric acid, a decomposition product by phosphatase, and found that the estimation of cholin is a very convenient method for the study of lecithase. He observed that the degree of injurious effect of ultraviolet ray on the formation of inorganic phosphoric acid is different from that on the formation of cholin from lecithin by Taka-diastase, the former being the highest at pH 6.6. After Pincussen's reports, the injurious effect of ultraviolet ray upon the enzyme is the greatest at the optimum pH for the enzyme. Therefore, we suspected that the optimum pH for lecithase may be different from that of phosphatase.
    In the following experiments, we have determined the optimum pH for lecithase by the measurement of cholin. For the estimation of cholin freed, we have used the following method: We added a small quantity of magnesium chloride solution and that of ammonia to the reaction mixture, filtered off the precipitates of magnesium hydroxide which includes the nondecomposing lecithin, added a iod-iodkali solution to the filtrate, separated the precipitate of cholin-periodide and solved in chloroform, and finally titrated freed iodine with N/100 thiosulphate solution. 1c.c. of N/100 Na2S2O3=0.14mgr. of cholin.
    To the lecithin-methylalcohol solution-0.5gr. of lecithin was solved in 5 c.c. of methylalcohol-40 c.c. of M/15 phosphate buffer solution and 20 c.c. of 5% Taka-diastase solution were added, and then the flask was filled to 100 c.c. with distilled water. After standing for a definite time at 36°-37°C, 10 c.c. of the reaction mixture was taken out, was filled to 11 c.c. with magnesium chloride solution and ammonia, and was filtered. Two c.c. of its filtrate was neutralised with hydrochloric acid, was added 0.2 c.c. of iod-iodkali solution, then cholin-periodide was collected by centrifuging, washed with the saturated NaCl solution at 0°C and was solved in chloroform. The iodine freed was titrated with N/100 Na2S2O3 solution.
    From the result of the experiment we see that the optimum pH-value for lecithase is near 7.0 (Table I.). Next, from the data we calculated the velocity-constant by using monomolecular equation and showed that the reaction velocity obeys the monomolecular reaction within 3 hours (Table II).
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  • [in Japanese]
    1932 Volume 1 Issue 2 Pages 81-88
    Published: August 10, 1932
    Released on J-STAGE: February 29, 2008
    JOURNAL FREE ACCESS
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