Using the procedure employed for the separation of fusarenon and nivalenol, toxic substances were separated from cereal grains infected with Fusarium in the crop field of Kagawa-ken in 1970. Production of the toxic substances in culture filtrates of the isolated strain was also determined. The results are summarized as follows:
(1) Fusarium spp., Alternaria spp., Aspergillus spp. and Penicillium spp. were isolated from moldy grains of barley and wheat. Fusarium roseum or related species were found to be a majority of casual fungi.
(2) Moldy grains mainly contained “Rd-toxin”, mp. 149. 5-151°C, and nivalenol, mp. 224-226°C, both toxic to mice and protozoa and the former was considered as a newly found mycotoxin having a scirpene nucleus.
(3) Phytotoxic butenolide, mp. 115-117°C, hardly detectable in the grains, and Rd-toxin were separated from culture filtrates of the isolated Fusarium roseum strain, whereas nivalenol was not detected.

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It is well known that canned asparagus dissolves tin from uncoated inner surface of the can in the short term of storage after manufactured, however the cause of this phenomenon has not been known. The present paper deals with the internal corrosion of canned asparagus and its correlation to the tin dissolving activity of cystine, cysteine and asparagus.
Extract of asparagus freeze-dried and stored at room temperature for 0-3 years was subjected to the test packing in baby-food cans. Closed cans were sterilized at 120°C for 20 minutes and stored at 38°C.
The corrosion factors were easily extracted with boiling methanol. They are inactive against cation exchange resin and stable in the acid medium but considerably unstable against alkaline solution. Thus, the action of detinning of four sulfur containing amino acids and relative substance were examined. When more than 500ppm of cystine is contained in the packed can, severe corrosion and sulfur stain was accelerated. Dried asparagus contained more than 15000ppm of cystine+cysteine.
The influence of oxygen or nitrogen substitution in the reaction medium were studied in the conection with the detinning action of cystine and cysteine. Cystine accelerated severe corrosion in the absence of oxygen, but cysteine promoted severe corrosion only at the presence of oxygen. Cystine and cysteine are assumed to be the factors which play one of the main roles in the proceeding of the corrosion in canned asparagus.

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The purpose of the experimental study was to clarify whether the deposited BHC in organs and tissues of rats would reduce with the dietary levels of protein, or whether the dietary protein levels would be related to the BHC deposition. The results obtained are as follows:
1) A protein-rich diet was effective in reducing BHC having deposited in organs and tissues. It was found that the effects were roughly proportional to the protein content of the diet.
2) It was recognized that the increase of the dietary level of protein lowered the deposition of BHC in organs and tissues, especially in liver.

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The strains of enteropathogenic Escherichia coli isolated from commercial foods in Niigata prefecture from 1969 to 1971 were surveyed for drug resistance to several chemotherapeutic drugs and distribution of R factors. Of 28 strains were examined, and 8 strains (8/28) were resistant to a number of chemotherapeutic drugs such as tetracycline (TC), chloramphenicol (CM), streptomycin (SM) and sulfonamide (SA), however, all of the isolates were sensitive to kanamycin, nalidixic acid and aminobenzyl penicillin. Of these resistant strains, 7 strains (7/8) were resistant to two or more drugs, and one strain (1/8) to only one drug. The majority of these drug risistant strains were the isolates from fresh meats.
It was also found that 4 strains (4/8) of these resistant strains carried R factors. All of the resistance patterns of R factors were multiple drug resistance.

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Ten kinds of frozen ready-to-serve sea-food were investigated bacteriologically. As the results, almost all samples were found to contain living cells of E. coli, Enterococci and Staphylococci, however, Vibrio parahaemolyticus, Salmonella and Shigella could not be isolated.
Among staphylococcal strains isolated from shellfish (Neptunea polycostata), two strains produced enterotoxic substances. One strain produced enterotoxin A, B and D, while another enterotoxin B and D. The production of these toxins were evidenced by precipitation against antienterotoxins and monkey feeding tests.
A refference strain of enterotoxigenic Staphylococcus aureus (S-6) produced more than 3.8 microgram of enterotoxin B in one gram of this kind of shellfish after incubation for 8 hours at 37°C. It seems that this amount of enterotoxin is enough to provoke food poisoning symptoms in adult when it is consumed.
It was confirmed experimentally that it needs boiling for ten minutes to sterilize frozen shellfish (Neptunea polycostata), completely.

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Technique to determine residual polychlorinated biphenyls (PCBs) has been complicated by the fact that PCBs are not single compound, but complex mixtures of isomers having various degrees of chlorination.
A method is described for the determination of PCBs through exhaustive chlorination.
The procedure is as follows.
1. Approximately 1μg of the ordinarily cleaned-up sample of PCBs is treated with 0.5ml of antimony pentachloride at 220°C for 2 hours in a sealed glass tube.
No prior separation of PCBs from DDE is required.
2. Decachlorobiphenyl formed is taken up into 20ml of benzene, and the solution is washed successively with 30% hydrochloric acid, 10% tartaric acid solution and water, dried by passing through micro-column packed with 1g of silica gel containing 5% water, and concentrated under stream of dry air.
3. Decachlorobiphenyl is analysed by gas-liquid chromatography with electron capture detector by using liquid phases such as DEGS-PA and OV-1.
At levels higher than 1μg, the described procedure gives almost quantitative yield of decachlorobiphenyl.
By this method total PCBs can be determined unequivocally as decachlorobiphenyl equivalent. Therefore, on assuming that residual PCBs constantly contain 50% chlorine, estimation of the amount of PCBs originally present can also be made with an error of up to 25%, because the chlorine contents of the common commercial PCBs preparations varies exclusivelyb etween 40 and 60%.

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The multiplication of psychrotrophic coli-aerogenes bacteria in milk or fish stored atchill temperature is already known. In order to investigate the sanitary significance of the organisms, some observations on the distribution of the organisms in mountain and residential area were carried out. At 14 of 16 stations along the Kita-akikawa and the Mitake-sawa, branch of the River Tama, the psychrotrophic coli-aerogenes bacteria could be isolated from the soil, bottom mud or water samples. On the contrary, at only 3 of 13 stations in the residential areas the organisms were detected. Seventy two strains of the psychrotrophic coli-aerogenes bacteria collected in this investigation were classified into 11 groups according to IMViC types, motility and gelatine liquefying ability. Majority of the isolates showed --++ IMViC type with positive reaction both in motility and in gelatine liquefaction test (Group I). Thirty one of the 72 isolates showed marked growth in glucose broth at 5°C within 1 to 2 days. Almost all the strains grew well at 37°C, while not at 40°C.
From the result of this investigation, it was revealed that psychrotrophic coli-aerogenes bacteria are widely distributed in mountain area.

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The bacterial fiora on the skin and in the muscle of spoiled raw fish stored at 0.5°C was investigated.
Enumeration and isolation of bacteria was conducted with smear plate method using 1% NaCl containing agar or 50% sea water agar medium. Ten samples of fresh sea fish were used in this experiment. One hundred and four strains were isolated from the skin of the fresh fish, and 150 and 148 strains were isolated from skin and muscle of the spoiled fish, respectively. Among the total isolates Pseudomonas group III/IV was predominant, and Vibrio, Pseudomonas II and I, or Moraxella constituted a small percentage of them. The isolates classified as the above-mentioned Pseudomonas IIII/IV were found to be devided clearly into the two groups on the basis of the difference in the salt requirement. The halophilic group was tentatively designated as Pseudomonas III/IV-H, while non-halophilic one Pseudomonas III/IV-NH. The majority of the Moraxella and the Vibrio strains also showed slightly halophilic property. On the contrary, all of the Pseudomonas I and II strains were nonhalophiles. About 90% of the isolates from the skin of fresh fish consisted of the Pseudomonas III/IV-H, III/IV-NH, Vibrio and Moraxella. After spoilage, the Pseudomonas III/IV-H, III/IV-NH and the Vibrio also dominated in the flora both on the skin and in the muscle, and percentage of the Pseudomonas II and I strains increased to some extent instead of decrease in the Moraxella. The spoilage ability at 5°C of the pure cultures was tested organoleptically using yellow-tail muscle. Several of the Pseudomonas III/IV-NH and III/IV-H strains and some of the Vibrio produced typical offensive spoilage odour, while the other group strains showed only some atypical odours.

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In the previous paper, it was shown that the bacterial flora in the spoilage of chilled raw fish mainly consisted of members of the Pseudomonas III/IV-H, III/IV-NH and the Vibrio group.
The present study was undertaken to investigate bacterial flora of frozen fish and the spoiled fish after thawing and storing at chill temperature.
For enumeration and isolation of bacteria the smear plate method was employed using 50% sea water agar medium described in the previous paper. From the skin of the five frozen fish samples 74 strains were isolated, while 75 strains were obtained from the skin and muscle of the spoiled fish samples, respectively. The majority of isolates from the skin of frozen fish consisted of the Moraxella, the coccal groups and the other undetermined group, and the Pseudomonas and the Vibrio, which were dominant on the fresh raw fish as reported in the previous paper, formed only a small proportion of the isolates in the case of the frozen fish. After spoilage, on the other hand, the Pseudomonas III/IV-H, II and I, which were absent before storage, appeared markedly, and they accounted for most proportion of the isolates together with the Moraxella, while the above-mentioned coccal groups and the undetermined group disapeared. The Pseudomonas III/IV-NH and the Vibrio, which are most important spoilage bacteria of raw fish, were isolated in a small number from the spoiled fish in the present work.

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Organochlorine pesticide residues in mothers' milk were examined in twenty-four prefectures at the beginning of 1971 (January to March).
In the present study α-, β- and γ-BHC, pp′-DDT, pp′-DDE and dieldrin were detected in mothers' milk. while pp′-DDD detected in cow's milk was not detected.
In general, the levels of organochlorine pesticide residues in mothers' milk were higher in West Japan than those in East Japan. Especially, BHC levels in mothers' milk were much higher in West Japan than those in East Japan, but other pesticide residues were not so different in both areas.
Compared peasant wives with non-peasant wives, the levels of organochlorine pesticide residues in mothers' milk of the former were a little lower than those of the latter.
Furthermore, when the results in the present investigation were compared with the tolerance of organochlorine pesticide residues in cow's milk, most of these mothers' milk were lower in the levels of the residues. However, if special regard was paid to the point that the tolerance of pp′-DDT were applied to total DDT, in total DDT residues, about 50% of the mothers' milk examined in the present study was over the tolerance of DDT.
The relationship of organochlorine pesticide residue levels in mothers' milk and some foods (meat, dairy products, and vegetables) were also examined.

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It was published in the previous report that mothers'milk was contaminated with organochlorine pesticides. At the same time, organochlorine pesticides residues in the blood from which the mothers offered their breast milk was examined.
In the presented study, α-, β-, γ- and δ-BHC, pp′-DDT, pp′-DDE and dieldrin were detected in mothers' blood during the lactation period, while pp′-DDD, aldrin and endrin were not detected.
On the whole, organochlorine pesticide residues in their blood were a little higher in West Japan than those in East Japan. The residues in blood of mothers in Hokkaido and Tohoku area were lower than those in other prefectures and then other prefectures were not so different in the residues each other.
Compared peasant wives with non-peasant wives, the levels of organochlorine pesticide residues in mothers' blood of the former were a little lower in β-BHC and total BHC than those of the latter, while the other pesticide residues were not so different between them.

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