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Volume 24, Issue 6-7
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Tomtoshi OKAICHI, Hisao KAI, Yoshiro HASHIMOTO1958 Volume 24 Issue 6-7 Pages 389-393
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSA rapid and marked color change was observed on a filefish, Stephanolepis cirrhifer (TEMMINCK et SCHLEGEL) and four distinct patterns were recognizabl (Fig. 1). Among twelve fish which ranged from 7 to 9cm in length and were kept in a tank of 60 litres capacity in the laboratory, there appeared two dominants assuming the pattern B, whereas the other subordinates indicated no dark pattern (A). When these dominants were removed from the tank, two dominants newly appeared soon. The dominant actively drove subordinates away and fought with the other to occupy the food and space (c and d in Plate I). The excitement in these activities induced the remarkable dispersion of melanophores (C and D in Fig. 1).
A rapid and extensive aggregation of melanophores resulting in the excitement pallor was also recognized when the fish were frightened violently. It is the most interesting fact that the time required for change of pattern is very short and the shift from one extreme to the other, for instance from D to A, occurs only in one or two seconds, and this may be the most rapid case so far known on fish (Table 1).
Among the fish kept in a large aquarium in the Ueno Zoo, on the other hand, there was recognized no order and every fish assumed the pattern B or C, whereas the same rapid excitement pallor was observed. The behavior of the fish in the laboratory, therefore, must be a specific one induced by the experimental condition, perhaps by the dense keeping of fish.
The similar color change due to excitement was also indicated by a different species of filefish, Rudarius ercodes (JORDAN et FOWLER) (Plate II).View full abstractDownload PDF (986K) -
Sueo M. SHINO1958 Volume 24 Issue 6-7 Pages 394-397
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (259K) -
Preliminary Research in Cultural ConditionsHideo IWASAKI, Chikayoshi MATSUDAIRA1958 Volume 24 Issue 6-7 Pages 398-401
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe present work was attempted to find what physical and chemical factors are necessary for the early development of the young buds of Porphyra tenera in culture. The results obtained are summarized as follows:
1. The young buds grew more rapidly under the sunlight than the artificial light. The sunlight below 25, 000 lux through a window glass was most favourable for the growth of young buds.
2. The young buds grew rapidly and healthily in daily light period. It seems that Porphyra needs an alternate light and dark-condition for the growth. The illumination of 8-9 hours per day is favourable for the growth in culture.
3. From the experiments of nitrogen and phosphorus requirements, it was found that good culture of the young buds can be obtained when potassium phosphate (monobasic) and potassium nitrate are added to the filtered inshore sea water.
4. The supply of iron as Fe-EDTA to the medium enriched with inorganic nitrogen and phosphorus promoted the growth of young buds. In iron deficient medium, the young buds grew dull in colour.View full abstractDownload PDF (275K) -
Yoshiichi MATSUI1958 Volume 24 Issue 6-7 Pages 402-406
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe fantastic conception that pearl formation originates from the dew-drop had been generally accepted from the beginning of the Christian Era until about the 16th century. Androthenus (1550) published his opinion that the pearl is comparable to measly of pigs, and led the way in the scientific investigations of the pearl formation hypothesis. Writers have sum marized these many hypotheses over and over again.
The pearl is a secreted substance formed in the body of certain mollusca, and there are various kinds of pearl which are formed by respectively different causes. Hence, most of the explanations of pearl formation hitherto published do not discuss all but only each particular pearl investigated by the respective author.
We define the pearl as a chemical substance formed in the body of bivalvia, the principal ingredient of which is calcium carbonate containing chonchioline, an albuminoid. We may induce pearl formation by a specific stimulation which in turn causes abnormal multiplication of certain cells which participate in the deposition of pearly substance.View full abstractDownload PDF (383K) -
Yunosuke IITAKA1958 Volume 24 Issue 6-7 Pages 407-410
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIt is a question whether Tauti's law on model experiment is tenable in such a small model as 1/250 or not. In order to check the validity of this law, a relatively large scale model experiment had to be made. An experiment was made with a 1/10 model in the sea to compare the results with the results obtained with the 1/250 model. The result is shown in Fig. 2, which shows a quite satisfactory agreement. Moreover, in the present experiment, the be haviour of the bottom margin of the net during pursing was observed using a newly deviced depth-meter and chemical tubes (Fig. 3).View full abstractDownload PDF (413K) -
Research in the Vicinity of Tsuyazaki, during Mar., 1957-Mar., 1958Keitaro UCHIDA, Yoichi SHOJIMA1958 Volume 24 Issue 6-7 Pages 411-415
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSTo make clear the relation between the life of fishes and the floating algae near shore, the authors carried out this research at Tsuyazaki Fishery Research Laboratory of Kyushu University. Fig. 1 and 2 show the collecting method. The results thus obtained during the period from March, 1957 to March, 1958 are summarized as follows:
1) The floating algae near shore have close relation to the young stage of some fishes locally well known.
2) The fishes accompanying the floating algae are abundant during spring to autumn but scarce in winter. The dominant species in each season are: Sebastes sp., Enedrias nebulosus and Seriola quinqueradiata in spring; Aluterid fishes in summer; Dasson trossulus in autumn; Girella punctata in winter.View full abstractDownload PDF (781K) -
Hisao KOBAYASI, Toru HAYASI1958 Volume 24 Issue 6-7 Pages 416-421
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSScale arrangement of 98 species of Japanese fishes is studied in this paper with the following results. (1) Scale arrangement can be classified into 5 types, viz., overlapped, mosaic, separated, irregular and single-lined. (2) Among overlapped-types of arrangement, a standard one consists of a set of 7 scales, varying in number from 9 to 11, 13, and anomalously from 8 to 10, 12. (3) One scale is no case overlapped by over 13 scales. (4) A set of 2-6 overlapped scales is in no case arranged regularly in the large part of the side of afish. (5) Systematically related fishes usually have a similar type of arrangement, but some of them have not.View full abstractDownload PDF (399K) -
Kozi WADA1958 Volume 24 Issue 6-7 Pages 422-427
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe crystalline structure of the nacre of Pinctada martensii was investigated with x-ray diffraction and the results were as follows:
1) The nacreous layer is found to be, not a single crystal, but aggregations of minute aragonite crystals all having their orthorhombic b and c axes parallel or nearly parallel to the fiber axes which are in agreement with the directions of growth parallel and normal to the inner shell surface, respectively.
2) The mode of the micro-crystal arrangements varies from portion to portion of nacres. 3) Orientation of crystallites seems to be more or less different between the discontinuous layers formed in the process of shell growth.
4) The crystalline structure of nacres is mosaic.View full abstractDownload PDF (1823K) -
The Estimation of Survival Rate by ObservationKôsi ONODERA1958 Volume 24 Issue 6-7 Pages 428-434
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSFor the estimation of the survival rate of fingerling trout stocked in a brook, a method through visual observation, by means of water-glass, was adopted. Some sample pools were taken for the observation, within the brook section of experiment (divided into Section I and II), and both the upper and the lower ends of a sample pool were blocked by setting screens to prevent the fish comming in or out the pool.
The number of fish dwelling in a sample pool was counted by observation and denoted as N', then, the fish in the pool was collected under an utmost effort by means of a circling seine, the number symbolized by C. Followed by the seining the fish remained still in the pool was sought by observation, deriving the number as (N-C)'. N denotes the true value against N'.
Then the rate of discovery, defined as r=N'/N may be calculated following the formula (1) found on page 430 of the text, and the rate of fishing, f=C/Nfrom (2) on page 430 could be established. The symbol C' denotes the number of fish observed which were assumed to have been mingled among the caught fish, therefore, the rate C'/C also carries the meaning of rate of discovery. The fraction C'/N' bears again the meaning of rate of fishing.
Considering the combined population of these sample pools, the author can estimate the synthesized discovery rate which represents that of total section surveyed from which sample pools were taken.
Apparent survival rate s1' which could be defined as the rate of apparent population size N2' measured by observational method at time t2 against the apparent initial population size N1' at time t1, could be corrected to the true survival rate s1' after the formula, s1=r1/r2•s1'.
As for apparent survival rate (s1)ε which is defined as the rate of apparent population size N1' at time t1 against the initial stocked population size P at time of planting tp, could be corrected to the true survival rate (s1)p as follows-(s1)p=1/r1•(s1)ε.
Finally the two corrective coefficients were induced, one kpt, which corrects the apparent survival rate at a given time tn against initial stocked population size to the true survival rate, while the other ktt corrects the apparent survival rate at a given time tn, against initial apparent population at the time tn-1 to the true survival rate.
Thus, the author has arrived,
1. Discovery rate, rj, at a pool, j, having population size less than about 100, was estimated to be between 0.6 and 1.4, and consequently,
2. The size of accompanied error of estimation of population size shown in proportion to the true size, or the size of relative deviation, Ej=1-rj, showed the range of 0.4>Ej>-0.4.View full abstractDownload PDF (420K) -
Variation of the specific growth and the relation between the average and the individual specific growth by a small population of the brown trout (Salmo trutta L.) reared in pondYasuo KODAMA1958 Volume 24 Issue 6-7 Pages 435-440
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe author intended to make clear the variation of the specific growth of an individual fish (R2) in a population and to compare the specific growth of the population ( ?? 1) with the average ( ?? 2) of the R2's obtained. The brown trout measuring eighteen with each fish marked by different tag, were reared in a small pond from July 2 to Augst 28, 1957, and total length of each fish was measured during the course. The results were obtained as follows: 1) although it was recognized that ?? 2 did not coincide with ?? 1 arose from formula (2) and (3) respectively, their difference was very small (Table 1). 2) It was observed that the larger the length of fish, the larger the R2 obtained, and producing a linear relation between them in each of the two periods of growth (Figs. 1 and 2). If the linear relation was expressed as R2=bγ+a (where γ means the representative of the length of a fish in one growth period), then it may be possible to connect ?? 1 with ?? 2 through the formula (5). The ?? 2 in Table 1 also derived from (5) actually produced precise estimate of ?? 2. 3) The fact of positive cor-relation existing between R2 and the length of fish will result the increase of the variation in the length in accordance with the growth of fish. Of population in natural body of water we would expect a more complicated relation existing between R2 and the length of fish than in the present case of confined water. The writer's another experiment of fingerling rainbow trout stocked in a mountain brook well demonstrated the fact, the variation of length of fish being extremely high and increase with the growth of fish.View full abstractDownload PDF (408K) -
Mitsutake MIYAMURA, Tsugihko MAKIDO1958 Volume 24 Issue 6-7 Pages 441-444
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn pearl culture, a graft tissue cut from the mantle of a pearl oyster is inserted into the body of the oyster together with a nucleus. The aim of the present experiments was to examine whether or not anatomical parts of the mantle from which graft tissues had been taken would have any effect on the quality of the pearl developed later in the body.
In the experiments the graft tissue was obtained from different sides of the mantle, the right and the left, each side divided into series of A, B, and C, with subdivisions I, II, and III (Fig. 1). The operated oysters were cultured in an area of Ago Bay for about four months till December 1954. The subsequent inspection, comparing the developed pearls in association with the graft tissues from the specific areas revealed:
1. In producing thicker layers of the pearl in term of weight, the graft tissues from the right side of the mantle was better than the ones from the left; A series of the tissue were as good as B series and better than C, the tissues from area III were the best followed by the tissues from areas II and I in this order (Table 1).
2. The occurring frequency of colored pearls differed between the graft tissues from each other side of the mantle, but did not among the tissues from other subdivisions of the mantle (Table 3).
3. The occurring frequency of lustrous pearls varied between these tissues compared with each other: A and C, III and II, III and I; but no differences was apparent between any other pair of the comparison.View full abstractDownload PDF (259K) -
Masaharu NISHIWAKI, Toshiro KAMIYA1958 Volume 24 Issue 6-7 Pages 445-448
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSA beaked whale that belongs to the genus Mesoplodon stranded on 22 Sept. 1957 at Oiso Beach, Sagami Bay, near Tokyo. Skull, vertebral column (C7+D10+L10+Ca21=48), and chevrons (11 in number) were collected in a complete set. Four distinctive characters from skull and mandibular are taken into special consideration in classifying the species of Mesoploden, and a key to the species of this genus was summarized basing on these characters. The authors concluded to settle for this specimen a new species and nominated as Mesoploden ginkgodens. The first specimen of Mesoploden from Japan was reported by OGAWA and identified as M. densirostris in 1935. It was examined again in the present work, and identified as the same species to the new specimen, viz. M. ginkgodens. As the space is restricted in this bulletin, the detailed report will be published in the Scientific Reports of the Whales Research Institute No. 13.View full abstractDownload PDF (2959K) -
Masao TAKAHASHI, Masayoshi HATANAKA1958 Volume 24 Issue 6-7 Pages 449-455
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe young mackerel were reared in a tank, fed with the known amounts of the anchovy and Euphausia. The ration and the daily growth were obtained for each individual mackerel.
(1) The relation between the ration and the daily growth can be expressed as a linear regression within the practical applications for the estimation of food consumption by the mackerel in nature.
(2) Under nearly the same sizes and the same temperatures, the anabolic rates of the mackerel in the case of giving the anchovy for food showed 0.23 to 0.30 (or 0.41 to 0.54 on calorie base) and those in the euphausid 0.17 to 0.22 (or 0.34 to 0.44 on calorie base).Thus, the former were higher than the latter.
(3) The decreasing rate of the anabolic rates in accordance with the unit growth of the mackerel was 0.0100 in the case of feed with the anchovy, while it was 0.0095 in the case of the euphausid. Therefore, the hypothesis used in the previous report2) that the decreasing rates of the anabolic rates are pararell between the two kinds of food, the anchovy and the euphausid, can be admitted.View full abstractDownload PDF (504K) -
Seasonal and Environmental Variation of Vitamin B12 Content in Tapes japonica and Meretrix mererix lusoriaJun'ichiro SAGARA, Masaaki YANASE1958 Volume 24 Issue 6-7 Pages 456-461
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIt has been reported that the vitamin B12 content of bivalves, and of starfish which devour bivalves, is higher than that of fish or other aquatic animals. Recent studies have shown that vitamin B12 will affect the growth of Porphyra tenera and relate to the development of “red tide”. In view of these facts, we made a study of vitamin B12 as one of some means to analyze the environment of the shallow water clam bed.
In this experiment we measured the vitamin B12 content of Tapes japonica and Meretrix meretrix lusoria, the bottom substances in which they lived, the fine deposits in the hollow of ripple marks and the plankton which are the food of clams.
Vitamin B12 content was determind by Euglena method added 1mg/cc acid hydrolysed casein to HUTNER's basal medium, and each sample were digested by trypsin before hot water extraction. Results obtained were as follows:
1. Vitamin B12 content in the soft body of Tapes japonica and Meretrix meretrix Zusoria is high before and during spawning, and low after spawning. In Tapes japonica, there is a tendency for individuals that live off the coast to be higher in vitamin B12 content than those that live near the coast; moreover individuals cultured by the hanging method are higher in vitamin B12 content than those raised in the above-mentioned benthic environment. In Mere-trix meretrix Zusoria, however, the above described tendency is not clear. Further, vitamin B12 content of Tapes japonica is higher than that of Meretrix meretrix lusoria during every month of the year (see Tables 1, 2, & Fig. 1).
2. Vitamin B12 content of the sandy bottom in the offshore areas is higher than in the shallow coastal beds, and vitamin B12 content of same substances divided into three vertical layers is higher in the upper and middle layers and poorer in lower layer. Fine deposits on the hollow of ripple mark are higher in Vitamin B12 than in the sandy bottom areas mentioned above. Vitamin B12 content in zooplankton (Copepoda) is higher than that of phytoplankton (Coscinodiscus sp. or Thalassiothrix sp.) (see Table 3).View full abstractDownload PDF (434K) -
Takeyuki DOI1958 Volume 24 Issue 6-7 Pages 462-465
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn determining a population size in the initial period of fishing or the size of recruit, the availability will be considered as a factor playing a greater role than mortality. Unless we take the availability into consideration in our treatment, therefore, it would be sometimes difficult for us to explain the fluctuations in fish catch by combination of any other factors. In this report, we, comparing the variations in actual catches and in theoretical catches calculated from the assumed population models, have proved that the availability can be computed with the aid of an analogue computer designed for analysing population problems.
In order to postulate the mathematical models of a population, the problems concerning the sardine, Sardinops melanosticta, exploited by the gill nets in the west Japan Sea, have been treated as examples, because the data such as fishing effort and age composition by gear are better available for the catch in this region than in other parts of our country.
Indicated in Fig. 1 are the comparisons between the actual catches and theoretical ones that are assumed in equations (1) to (9) for various combinations of gear efficiency and natural mortality; in Fig. 3 are the comparisons for another combination assumed after the previous treatment in equation (10). Except for 1953 in Fig. 3, the patterns of theoretical catches in these figures do not fit to the actual ones in any combination of gear efficiency and natural mortality.
Therefore, we have to compute the availability by assuming the most probable values of efficiency of gear (1/100, 000) and coefficient of natural mortality (0.5). In Table 1 showing the results obtained, the column A indicates the availability compared with the preceding year, and the column B series of relative availability compared on the basis of 1951. The reasons making the availability vary from year to year and the questions concerning the structures of mechanisms by which the conditions of the initial abundance of a population or recruit will be established are important problems to be solved in the future.View full abstractDownload PDF (251K) -
Yoshio HIYAMA, Takaya KUSAKA, Yoshiaki YAMASHITA1958 Volume 24 Issue 6-7 Pages 466-468
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSAs a fundamental experiment concerning effect of lift net, the authors studied the relation between mesh sizes and fish lengths of catches in model lift nets.
The set of the observation was shown in Fig. 1. as a material of fish was used Carp Cyprinus carpio. Population of the carps in the tank is explained on the upper column of Table 1. as the total number 197 individuals. They were taken into consideration on the population to be approached in the natural condition. Net materials were used of mesh sizes 6, 3 and 1.5cm. and the lifting speeds of the net were selected 3 grades at 5, 10 and 20 seconds per 88cm.
The results obtained were shown in Table 1. and Fig. 2. for the number of the fish lifted and the catching rate. Fig. 3. were shown a effect what is a indicator of catching efficiency against a certain mesh size and fish length.View full abstractDownload PDF (210K) -
Saburo KAWADA, Yozo YAWARA1958 Volume 24 Issue 6-7 Pages 469-474
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIt is important for improving the catching efficiency of set net to detect the swimming course of fish schools in fishing areas. For this purpose the experiments were carried out at Yoshihama Bay, Iwate Prefecture during November to December, 1954 (Table 1).
Two survey boats, each installed with a vertical type of fish finder, sailed back and forth along the detecting course selected as shown in Fig. 1. A number of points where we encountered with fish schools, were plotted on a chart to calculate the encounter index. The swimming course of fish schools was estimated as follows.
The fish schools which enterd the northern part of the bay, at a speed of 0.5-2m/sec (Tables 3 and 4), swam to the south along the isobath of 40-60 meters and reached at the front of the set net. According to our observation they were expected to fall into the set net on their way of going out the bay (Figs. 3 and 4).
Further studies are under way to obtain better results by using simultaneously a vertical type and a horizontal type of fish finder.View full abstractDownload PDF (298K) -
Shiro FUJITA1958 Volume 24 Issue 6-7 Pages 475-479
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSSebtases oblongus GÜNTHER is a common viviparous scorpaenid fish in Japan. From November to December, 1955 and 1956, the author reared female parent fish incubating fertilized eggs, and observed the development in the egg squeezed from the parent fish. Spawned larvae were also reared for about one month in a glass jar, feeding the brine-shrimp nauplii.
On November 23, 1956, a female parent fish (210mm in total length) bearing developing eggs at 16-cell stage (Fig. 1) was caught and kept in an aquarium. In 7 days after being caught, this fish abnormally released all the eggs at 27-myotome stage. On November 29, 1956, another female (208mm) with developing eggs at more advanced stage (Fig. 6) was caught and kept in an aquarium. In 171/2 days after being caught this fish naturally spawned larvae in the tank.
Fertilized eggs at the early developing stages are spherical in shape, measuring 1.55-1.60mm in diameter, with a number of orange oil-grobules. In the coures of development, the eggs became larger and changed in shape (Figs. 1-8). Newly spawned larvae (including the one of Fig. 9), measuring 7.25-7.50mm in total length had 27 (8+19) myotomes and swam freely in the glass jar. The melanophores and small xanthophores were distributed on the top of head, on the back of trunk, around the intestine tube, and on the middle part of the tail, but none on the pectoral fins. In 5 or 6 days after being spawned, the larva (7.20mm) consumed all the yolk and began to eat the brine-shrimp nauplii. In 25-30 days after being spawned, the larvae (including the one of Fig. 12), measuring 12-14mm in total length, reached the end of the post-larval stage. All the fins were well formed with a complete set of fin rays (D, VIII-13-14, A, 111-7, P, 16, V, 1-5).View full abstractDownload PDF (405K) -
Otohiko SUZUKI1958 Volume 24 Issue 6-7 Pages 480-482
Published: 1958
Released on J-STAGE: February 29, 2008
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On the Effects of Light-intensity and Water-tamperature upon the Rate of Photosynthesis-1Yunosuke SAITO1958 Volume 24 Issue 6-7 Pages 484-486
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe rate of photosynthesis of Undaria pinnatifida was measured by the quantity of oxygen evolved from the materials which were kept in various conditions concerning light-intensity and water-temperature.
Results obtained may be summarized as follows:-
(1) The photosynthesic rate was accelerated with the increase of light-intensity, and reached to a maximum at a intensity correlating to the water-temperature; i.e. at 10-15°C at 20, 000 lux and at 5°C at 30, 000-35, 000 lux.
(2) Under a definite illumination the photosynthesic rate was accelerated with a rise of water temperature, and the highest value was usually observed at 20°C, but the rate decreased at 25°C. The ratio increased with rise of water-temperature was more gradually under 30, 000 lux than under less light-intensity.View full abstractDownload PDF (208K) -
By Kenji KUROGANE, Yoshio HIYAMA1958 Volume 24 Issue 6-7 Pages 487-494
Published: 1958
Released on J-STAGE: February 29, 2008
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Nakaroku NAKAMURA1958 Volume 24 Issue 6-7 Pages 495-500
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe thriving of phytoplankton is believed as one of the most important factors concerning directly to the daily appetite and respiration of fishes in the eel-culture ponds.
The author had deviced a new method to denote the degree of phytoplankton thriving by the measurements of the transparency using a small china disc, and also, had cleared to specify and notate the water-color numerically by the Munsell Color System. Using these new methods, I have studied on the seasonal variation of phytoplankton thriving and its particle size in many eel-culture ponds.
The results so far are as follows:
(1) Chlor content, transparency and water-color of pond waters in five main eel-cultural districts in Shizuoka, Aichi and Mie Prefectures are summarized on Fig. 1.
(2) Respective characteristics of plankton thriving in the ponds of these districts are compared with each other and seasonally by plotting the ratio of chlor content, transparency and hue value of water-color on the triangular co-ordinates (Fig. 2, 3).
(3) While phytoplankton of a minute particle dominates in the ponds in which chlor content of water is higher, relatively macro-sized plankton colony thrives in the fresh-water ponds and especially in the warmer season.View full abstractDownload PDF (349K) -
On the Relation between the Visual Range of Net Twines and the Turbidity of Surrounding waterNaoichi INOUE, Satoshi NISHIZAWA, Kozaburo TAMUKAI, Takao KUDO1958 Volume 24 Issue 6-7 Pages 501-506
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSVisual range of net twines with different colors and diameters (Table 1) was observed succesively in an experimental tank (Fig. 1) containing water of serially different turbidity (Fig. 2). Variations of visual range with the wave length of incident light was also observed using a series of color filters (Table 2 and Fig. 3).
Visibility or visual range γ of net twine in water of turbidity k seen from the light source of parallel illumination is expressed by the following equation;
ε=e-2kr(8R/f180-1),
where ε is the contrast threshold of observer, R is the luminous albedo of the net twine and f180 is the mean relative backward scattering function of surrounding water. The value of ε of an observer is generally a function of the brightness of background and the visual angle θ of target. In this experiment the value of ε was calculated by observing long and narrow strips of grayish paper of different width with known albedo, backgrounded by a constant brightness, and the following experimental formula was obtained (Fig. 4 and Fig. 5);
ε=ε0/1-e-θθ
where ε0 and α are parametric constants depending probably on the background brightness and the shape of target, respectively. The backward scattering is generally very difficult to obtain, therefore the values of
ε/e-2kr=8R/f180-1≅B
were calculated to test their constancy through a series of experiments with a fixed twine (sample No. 1) and any one fixed color filter, the results being shown in Table 4. The variation of this value with the turbidity of water is not negligibly small except in the case of green light.View full abstractDownload PDF (336K) -
1. test of copper as a barrier for Japanese drill, Tritonalia japonicaT. IMAI, S. ITO, K. SHIRAISHI, T. SHIBUYA1958 Volume 24 Issue 6-7 Pages 507-510
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSOn suggestion of John B. Glude, Fish & Wildlife Service, U. S. A., tests were made to see if metal copper plate would be useful as a barrier to control the Japanese drill, Tritonalia japonica as it is for the Atlantic drill, Urosalpinx cinerea. Various copper paints were also used for the test.
1. Tritonalia japonica reacts sensitively against Cu ion in sea water. They show a contraction of foot at the concentration of 0.5γ Cu++/cc. Complete closure of operculum was observed in 50 percent of the individuals tested at 10γ Cu++/cc and in 100 percent at 20γ Cu++/cc.
2. Copper plate, copper paints were found effective in repelling the drill, T. japonica but not for Rapana thomasiana. Its effect on Thais tumulsa was dubious.
3. Among paints tested, Vinilex copper paint showed the best results comparable to copper plate, for a period of 5-6 months. Ordinary copper paint was effective for less than a month.
A period of lasting effectiveness was assumed to depend on the lasting dissolution of Cu ion.
4. In field test it was confirmed that copper plate and Vinilex copper paint can be used as an efficient barrier of controlling the Japanese drill, T. japonica.View full abstractDownload PDF (295K) -
On the volatile Component of Xanthoxylum piperitumTeruhisa KATAYAMA1958 Volume 24 Issue 6-7 Pages 511-514
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESS1. The presence of citronellal was confirmed in the carbonyl fraction of the seeds of Xanthoxylum pipertum.
2. A terpene fraction was fractionated using a FENSKE column and the presence of d-limonene and β-phellandrene was confirmed as the bromide and nitrosochloride. The presence of terpinolene, linalool, 1:8-cineol, and α-termpineol was clarified by chromatostrip. The presence of an ester giving a spot at Rf 0.50 was found in a fraction boiling at above 94°C.View full abstractDownload PDF (201K) -
On the Fire-Retardant Property of the ProductKosaku SUZUKI1958 Volume 24 Issue 6-7 Pages 515-518
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe chlorination product was examined of its fire-retarding property toward wooden pieces, promising to be used as one of ingredients of a fire-retardant coating base. The intact wooden pieces burned with flames of course, whereas the pieces treated with this product generated no flame when heated in an electric furnace at a considerably high velocity of heating.
The fire-retardative effect of the product was especially prominent toward Sugi, cryptomeria, though also appreciable even toward Nara. one of the “hard wood”.View full abstractDownload PDF (256K) -
A Spectrophotometric Method for the Simultaneous Determination of Ferrous and Ferric Forms of Myoglobin in their Mixed SolutionYoshihiko SANO, Kanehisa HASHIMOTO1958 Volume 24 Issue 6-7 Pages 519-523
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn order to investigate the discoloration of tuna meat during freezing storage, it is necessary to follow quantitatively the metmyoglobin (MMb) formation responsible for browning. As no precise methods for determining the amount of met-form in fresh meat have so far been reported, a new spectophotometric method was devised.
As accepted usually, there exist three forms of myoglobin (Mb), reduced Mb, oxy-Mb (MbO2) and MMb in the meat. Among these three, the former two can be converted readily to carbonyl-Mb (MbCO) by exposing them to carbon monoxide (Case 1). All the derivatives can be converted into MbCO by treating them similarly with CO after reducing MMb with sodium dithionite (Case 2), and also into MMb by adding a trace of ferricyande solution (Case 3).
If the optical densities at 568mμ (α-max. of MbCO of fish) in Cases 1, 2 and 3 are designated as d, a, and b, respectively, the relative amount (X%) of MMb to total Mb in the solution can be calculated by the equation:
X=a-d/a-b×100
(Fig. 1).
To avoid the autoxidative change to MMb from ferrous Mb in the experiment, temperature should be kept as low as possible and pH near the neutral (cf. Figs. 2 and 3). The application of neutral pH is further reasonable, in view of the fact that the absorption spectrum of tuna MMb changes with pH, E568mμ increasing in alkaline side (Table 1). Accuracy of this method was good, as judged from the results of experiments obtained for the mixture of known amounts of pure preparations (Table 2). An example of application of the method was shown in Fig. 4, which indicates that the lower the pH is, the more rapid the MMb formation (cf. Fig. 3).View full abstractDownload PDF (375K) -
Eizaburo NOGUCHI, Joji YAMAMOTO1958 Volume 24 Issue 6-7 Pages 524-530
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn this report, we examined the improvement of keeping quality of fish achieved by application of hinokitiol (m-isopropyl tropolon), sodium hinokitiolate and asnalon (oil of Thujopsis dolabrata SIEB.).
Fishes previously kept immersed in 0.01% or 0.02% solution of hinokitiol for about one or two hours were stored at room temperature. Hinokitiol, sodium hinokitiolate and asnalon were recognized to be the same with one another in respect of apparent effectiveness, and freshness of the fishes treated with these agents was maintained almost two or three times longer over that of the control. Asnalon, however, is not suited for actual use because of its intense oder and bitter taste.
It has been ascertained that the preservative power of hinokitiol for fish is attributable at least in part to its inhibitory effect on protease activity (see Table 4).View full abstractDownload PDF (542K) -
On the Electrophoretic Specificity of Serum Lipoprotein and GlucoproteinKaname SAITO1958 Volume 24 Issue 6-7 Pages 531-534
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSSerum protein was isolated from a few fishes by the paper electrophoresis. The protein contained glucoprotein as well as lipoprotein, which were detected by the periodic acid SCHIFF reaction and sudan black-B reaction, respectively. The electrophoretic patterns obtained indicate that, not to mention the contrast between fish and other animals, the relative mobility of serum protein is possible to greatly differ even within the realm of fish as it is the case between elasmobranchs and teleosts.
The lipoprotein-and glucoprotein-reactions were positively found in the case of serum protein of teleosts such as carp, gray mullet or red snapper in an albuminlike fraction (component F or 1) judged as such from its large relative mobility, while albumin fraction of human serum or rabbit serum, both used as contrast, showed only negative ones. With elasmobranchs like shark and ray, on the other hand, these reactions were particularly distinct rather in a fraction of lower mobility (component 4) as compared with the faster fraction (component 2).
These results might allow to assume that such animals having marked difference in taxological status are generally attached also by a profound difference in protein composition without connection to the apparent similarity their serum protein shows in electrophoretic mobility.View full abstractDownload PDF (195K) -
The Difference in the Chemical Composition of Normal and Browned Canned Crab MeatYoshio NAGASAWA1958 Volume 24 Issue 6-7 Pages 535-540
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (341K) -
Yoshihiro SATO, Reizo IWAMATSU, Michitaro TAKAHASHI1958 Volume 24 Issue 6-7 Pages 541-544
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe volatile basic-and amine-N of the fish sold at the store in Sendai, August 1957, were determined by Conway's microdiffusion method and the results obtained were summarized in Table 1. Comparing the values with those in fish of May and June 1957, the quality of marketing fish was better in summer (26-35°C) than in spring (18-25°C) (Table 1-3). This fact will be caused by the rapid transportation from the fishing ground to the fish store and the proper treatment of fish with ice in August.
It was found that the percentage of fish of the poor quality was small in the well equipped store (Table 5) and that comparing the bottom fish with the surface fish, the former always had the high value of the volatile amine-N in comparing with the volatile basic-N (Table 1, 6).View full abstractDownload PDF (333K) -
Various Effects of Phosphate on Qualities of “Kamaboko”, Fish CakeKazuhiro OKAMURA, Tosio MATUDA, Mitio YOKOYAMA1958 Volume 24 Issue 6-7 Pages 545-550
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSI. These salts had desirable effects upon the jelly-strength of “Kamaboko” as it is indicated as following:
a. Na-pyrophosphate was the most effective one as well as Na-tripolyphosphate when it was used in concentration of 0.1-0.3%.
b. Na-hexametaphosphate and Na-secondary-phosphate were not so effective as Na-pyrophosphate when they were used in the same concentration as Na-pyrophosphate.
c. The addition of Na-tertiary-phosphate, Na-tatarate, Na-succinate and Tari indicated no effects upon the products, but we did not find any change in jelly-strength due to the addition of the salts.
d. It is assumed that the desirable effects of phosphates upon the jelly-strength of “Kamaboko” are due to the characteristic properties of phosphates themselves rather than alkalinities of the phosphates.
II. Concerning the taste and flavour of “Kamaboko” in the experiment of Na-pyrophosphate, Na-tripolyphosphate, Na-secandary-phsophate, Na-hexametaphosphate, Na-tertiaryphosphate, Na-tatarate, Na-succinate, and Tari with the addition of 0.1-0.3% concentration:
The addition of these salts, expect Na-succinate, scarcely influenced the taste and flavour of “Kamaboko” products. Even with the addition of 0.03% concentration Na-succinate gave the characteristic taste of the clam to “Kamaboko”.
III. The inter-relationship between the pH values shifted to alkali side by the addition of these salts, and the deterioration of “Kamaboko”:
The pH values of “Kamaboko” products increased by the rate of 0.1-0.4, with the addition of these salts, and this increase of pH values did not affect the putrefaction of “Kamaboko” products nor gave any particular influence upon the mode of it's products in the result of our experiments.View full abstractDownload PDF (474K) -
Takeaki KIKUCHI, Toshiyuki HIRANO, Akira ONUKI, Ikunosuke OKADA1958 Volume 24 Issue 6-7 Pages 551-554
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSFor the studies of protein contained in muscle of an aquatic animal on the basis of polarographic wave, it is necessary to grasp a protein wave typical of meat extractives of the aquatic animal. Here, the authors studied the method to determine a polarographic protein wave typical of meat extractives of aquatic animals. We also studied into the origin of the protein wave. The results are as follows:
1) In order to obtained the typical wave for meat extractives, it is necessary to change the amount of meat extractives relative to the ammoniacal cobaltic solution according to the extraction ratio of meat (Table 1).
2) It is experimentally ascertained that the polarographic waves treated here originate purely in protein and have no relation to non-proteinous extractive components of meat.View full abstractDownload PDF (242K) -
Determination of Muscle PigmentTsunetoshi KANEMITSU, Hiroshi AOE1958 Volume 24 Issue 6-7 Pages 555-558
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThree methods for estimating astaxanthin, the only carotenoid occurring in the muscle of Pacific salmons have been devised as follows:
(A) The muscle (5g) was ground in a mortar and the pigment was several times extracted with acetone. The combined acetone extracts were concentrated at room temperature under nitrogen, and the pigment was extracted with petr. ether. This solution was run through a column (3.5×30cm) of cellulose powder (20g), and the column was washed with about 80-100cc of petr. ether to remove fat completely. The pigment adsorbed on the cellulose powder was then eluted with acetone. This acetone fraction was concentrated, and its volume was suitably adjusted with acetone for spectrophotometric measurement with Beckman spectrophotometer. Regarding the difference between values at 478 mμ and 600 mμ as accounting for astaxanthin, the amount of astaxanthin in fresh muscle was calculated using the value of E1%1cm (478 mμ)=2, 200 for pure astaxanthin in acetone.
(B) The petr. ether solution of the pigment prepared as A, was added with small amount of anhydrous Na2SO4, and filtered through No. 4 glass filter. After removal of the solvent, the residue was dissolved in a suitable volume of petr. ether for spectrophotometric analysis. The extinction was measured at 470 mμ and 600 mμ, and the calculation was the same as A, except that E1%1cm (470 mμ)=2, 400 was used for pure astaxanthin in petr. ether.
(C) The muscle was extracted with acetone as A. The volume of this solution was immediately suitably adjusted for spectrophotometric analysis. Extinction measurement and calculation were made as A.
In the methods A and B, the recovery of added pure astaxanthin was 94.4-97.6% and 97.0-98.7% respectively. And there was no appreciable difference among the values obtained by the methods A, B, and C on the same material (Table 1).
By these methods, astaxanthin concentration was determined on the dorsal, ventral, and caudal muscles of five species of North Pacific salmons (Table 2), on the muscle of some individuals of red salmon caught at different stations, and also on that of five species from the same station (Table 3). So it was ascertained that the muscle of red salmon is most rich in this pigment, and there was found no distinct relationship between theamount of the muscle astaxanthin and sex, body weight, body length and fattiness.View full abstractDownload PDF (341K) -
On Some Physico-Chemical Properties of a Film of the Ryphan (Rubber Hydrochloride) and the Krehalon (Polyvinyliden Chloride) Used as the Casings of Fish SausageSaburo UENO, Toru HASIMOTO, Wataru SIMIDU1958 Volume 24 Issue 6-7 Pages 559-562
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSSome physico-chemical properties of a film of the Ryphan have been compared with those of the Krehalon in reference to the value in being used for the casings of fish sausage, and we have obtained the following results.
1. When the films are heated in hot water, a great deal of chlorine ion is liberated from the Ryphan, but it is not so with the Krehalon.
2. A great deal of chlorine ion is observed to be isolated from the film of either Ryphan or Krehalon when it is exposed to the germicidal lamp, the film coming out dark brown. This phenomenon is more remarkable in the Krehalon.
3. It has been discussed that the discoloration of nitroso-heme in cooked whale meat may be based upon the oxidation, and the Krehalon, which is air-proof, is found preferable to the Ryphan in the prevention of discoloration.View full abstractDownload PDF (318K) -
Amino Acid Composition of Tuna MyoglobinShoji KONOSU, Kanehisa HASHIMOTO, Fumio MATSUURA1958 Volume 24 Issue 6-7 Pages 563-566
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSAmino acid composition of myoglobin (Mb) of tuna, Thunnus orientalis, was determined. The globin, prepared from the thrice-recrystallized Mb, was hydrolyzed with 20% HCl for 24 hrs. and analyzed by the method of STEIN & MOORE7). The hydrolyzate for tryptophan was prepared after GREENE6) and analyzed similarly. Cystine and/or cysteine were determined by the method of SCHRAM5). The elution curves are shown in Fig. 1. The amino acid composition of tuna Mb was shown in Table 1, together with that of hemoglobin (Hb) of tuna, T. thynnus13), and that of mammalian pigments.
Distinct differences were discerned between Mb and Hb of tuna, as seen in the case of horse11) or human14). Most of relative quantitative differences of corresponding amino acids, however, were similar to those observed in the cases of mammalia, except for leucine, methionine, and histidine, etc.
Next the following differences are pointed out by comparing amino acid composition of tuna Mb to that of mammalian Mb's:
(1) Amongst monoamino-monocarboxylic amino acid, alanine is most prevailing in tuna, whereas leucine in mammalia.
(2) Tuna Mb contains one cysteine residue, the absence of which has been reported for mammalian Mb's (cf. Table 1 and ROSSI-FANELLI et al.14)).
(3) In tuna Mb, glutamic acid and basic amino acids are considerably poor.
The percentage distribution of groups in tuna Mb and the others are shown in Table 2. Tuna Mb is scant in free anionic and cationic groups. Accordingly the total of both groups of tuna Mb is less than that of mammalian Mb and rather comparable to its Hb. However, the difference between two groups reveals the more or less basic nature of the globin. The total of polar groups of tuna Mb was found also to be low as the total of ionic groups is, which will account for the relatively low solubility of tuna Mb reported before2).View full abstractDownload PDF (306K) -
On the Unpleasant Odorous Acid of Rain Spoilt Dried-squid (II)Tei YAMANISHI, Yasuko KAJIKAWA1958 Volume 24 Issue 6-7 Pages 567-568
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSWe have obtained a waxy and acidic substance with strong offensive odor which is characteristic to rain spoilt dried squid. When the waxy substance was heated at about 160°C, needle like crystalline (I) was formed by sublimation. We reported about (I) having an empirical formula of C2H4O.
By this experiment, we were able to isolate the another acid as a flat leaf form crystalline by heating at 200° ?? 205°C the residue formed by the process of obtaining (I) from the waxy substance. We found it to be phenylacetic acid (II) by its infrared and ultraviolet spectrums, and by test of mixed melting point. The waxy substance consists of about 70% of (I) and 30% of (II).View full abstractDownload PDF (131K) -
Fatty Oils from Salmon EggsKoichi ZAMA, Muneo KATADA, Hisanao IGARASHI1958 Volume 24 Issue 6-7 Pages 569-572
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSUnfertilized and fertilized (after 24 hours) salmon eggs were repeatedly extracted with acetone. The acetone extracts were further treated with acetone to yield the fatty oils as acetone-soluble lipids.
The properties of these lipids presented in Table 1 showed no difference between the lipids of both eggs.
Percentage composition of the fatty acids of the fatty oil from unfertilized egg was as follows: saturated C14 4.8, C16 11.1, C18 3.5, and C20 0.5, unsaturated C14 0.2 (-2.0H), C16 13.2 (-2.5H), C18 36.2 (-3.0H), C20 20.1 (-8.5H), and C22 10.4 (-10.0H).
The presence of C18-alcohols and glyceryl ethers were found besides cholesterol in the unsaponifiable matter.View full abstractDownload PDF (250K) -
Folic Acid and Folinic AcidAkio KANAZAWA, Daiichi KAKIMOTO1958 Volume 24 Issue 6-7 Pages 573-577
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSStudying into the folic acid (FA)-and folinic acid (CF)-contents of various seaweeds obtained from the southern sea coast of Japan, the following results were arrived at:
1. Not only in FA content but in CF, no notable specific variations were found between different groups of algae, while some remarkable differences were found rather between different algae belonging to the same group. A highest amount of FA was obtained with Hydroclathrus clathratus and a lowest with Endarachne binghamiae, the values being 860 mγ/g and 35 mγ/g, respectively. As regards CF content, a maximum value was found for Ceramium tenerrinum and a minimum was for Ectocarpus indices, the figures being 930 mγ/g and 12 mγ/g, respectively.
2. It was found likely that in general seaweeds contain much more FA than CF.
3. As to the distribution of the two kinds of “Free form” and “Conjugated form”, the former of FA was entirely absent in Ceramium tenerrinum and Gloiopeltis complanata and no trace of CF in “Free form” was present in Gracilaria verrucosa, either of the FA and CF estimated being in “Conjugated form”; but in general seaweeds hold “Conjugated form” much more abundantly than “Free form”.
4. In Porphyra tenera no considerable seasonal variations were seen in the both factors.
5. In seaweeds autolytic liberation of FA and CF from the conjugated form was scarcely met with. This suggests that the conjugase activity is very weak in these plants.View full abstractDownload PDF (339K) -
The Composition of Fatty Alcohols in the Pacific Beaked Whale Blubber Oil.Masamichi SAIKI, Shin-chen FANG, Takajiro MORI1958 Volume 24 Issue 6-7 Pages 578-580
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe quantitative composition of fatty alcohols in the blubber oil of a pacific beaked whale, Berardius bairdii, was determined (Table 6). In this analysis, alcohols were previously fractionated before fractional distillation by the Urea adduct-Me OH method3)4) (unsaponifiable matter: urea: solvent=1:2:20), which was very effective to separate octadecenol (Tables 3 and 6).
The saturated and unsaturated alcohols were found to be 38% and 62% respectively, and the latter is almost entirely consisted of monoethenoid alcohols by the oxidation method with KMnO4 in acetone solution. The fatty alcohols are mainly composed of octadecenol (53%) and octadecanol (27%), and the presence of such a large quantity of octadecanol has not been so far reported on marine animal oils.View full abstractDownload PDF (212K) -
Effect of chlortetracycline (CTC) treatment on quality of salt sardine and salt mackerel, and change in CTC residue during saltingTetou TOMIYAMA, Tohru SUGITANI1958 Volume 24 Issue 6-7 Pages 581-585
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn brine salting of sardine, the addition of a 10-ppm level of CTC to a 10% brine was capable of preventing the fish from spoilage for two days at 20°C. An excellent quality of salt sardine was obtained when the fish was dipped for one hour in a CTC (20 ppm)-brine prior to the dry salting. In both the brine salting and the dry salting of sardine it was found that the CTC treatment could reduce the necessary amount of salt to one-half as much.
The decrease in CTC content of brine as well as tissue during the brine salting of mackerel took place linearly with time of dipping. The CTC residue of the dry salt sardine after a 4 day storage at room temperature was found only 0.03 to 0.17 ppm.View full abstractDownload PDF (379K) -
Changes in Muscle of Yellowtail (Seriola quinqueradiata) during Cold StorageUsio SIMIDU, Hiroyoshi TERASHIMA, Wataru SIMIDU1958 Volume 24 Issue 6-7 Pages 586-590
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (233K) -
Electrodialysis of Sea Water and the Stability of Vitamin B12 in Sea WaterKen-ichi KASHIWADA, Daiichi KAKIMOTO, Akio KANAZAWA, Kazunori KAWAGOE, ...1958 Volume 24 Issue 6-7 Pages 591-594
Published: 1958
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSWe have formerly reported on a method presented to determine the vitamin B12 in sea water. On that occasion sample sea water was previously desalted by dialysis against running fresh water, using cellophane as diaphragm, so that the vitamin B12 content might be properly estimated by the Euglena method. In the present experiment we confirmed the superiority of electrodialysis over running water dialysis, and also examined the stability of vitamin B12 in sea water. The results obtained were as follows.
Desalting of sea water was found to be accomplished in a shorter time by electrodialysis than by running water dialysis (Table 2).
As to the stability of vitamin B12 in sea water, on the other hand, it was made clear that:
1) Loss of vitamin Bit in sea water proceeds with a considerable velocity in diffused day light, while the loss is evaded almost completely even throughout 20 days storage if the sea water is kept in brown light or in the dark (Table 3).
2) Intentional neutralization or acidification of natural sea water lessens the rate of loss of vitamin B12 in diffused day light; but such processing is never to be looked on as a conclusive way of keeping the vitamin B12 perfectly fixed (Table 4).
3) In a sea water being exposed to the sun, its vitamin B12 content decreases very rapidly (Table 5).View full abstractDownload PDF (325K)
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