Various phytotoxic symptoms were observed on young Chinese cabbage plant when it was applied with 27 organophosphorus insecticides. These symptoms are classified as follows; leaf-necrosis, leaf-yellowing, abnormal leaf-vein, and normal. Relations between such phytotoxic symptoms and change of some enzyme activities, which had been recognized to change in abnormal plants caused by infection with fungal or viral pathogens, deficiency of nutrient etc., were investigated through the disc electrophoresis on polyacrylamide gels. In case of the isoperoxidase, two bands were detected in the extract of the non-treated leaves, that is, one was much in young leaves and other increased in older leaves. Degree of dark colouring of the later band became strong by insecticide treatments. The strongest band was observed on the plant with severe leaf burn. Three bands of acid phosphatase activity were detected on the normal plants, but the center band was more strong in the treated plants shown severe leaf burn, and an additional fourth band appeared in the most cases of insecticide treatments. In case of glutamic acid dehydrogenase activity, one band was detected in the non-treated plant, but two bands were found in the plant with leaf-necrosis. Two main bands of non-specific esterase were detected, one increased in new leaves, and other in older leaves. The later band in esterase was weak in the leaf-yellowing plants. But, no correlations were found between the occurrence of esterasebands and the symptoms of leaf-necrosis.

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Identification of urinary metabolites of an urea herbicide, 1-(α, α-dimethylbenzyl)-3-(p-tolyl)urea, dymrone, was investigated in male Wistar rats. After intraperitoneal (i. p.) administration of carbonyl-¹⁴C-dymrone (100mg/kg, single), 77% of the dose was eliminated in the urine. Urinary major metabolite was found in the acidic fraction of urine and accounted for greater than 85% of urinary excreted radioactivity. This major metabolite was isolated in crystal from the urine of rats repeatedly treated i. p. with non-radioactive dymrone (100mg/kg/day for 10days) and identified as 1-(α, α-dimethylbenzyl)-3-(p-carboxyphenyl)urea by tlc, NMR, IR, and Mass spectra. In addition, one of the minor metabolite in the urine was suggested as p-carboxyphenylurea by tlc.

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Ten L-5-alkyl- and alkenylthiomethylhydantoin S-oxides (alkyl or alkenyl: methyl, ethyl, propyl, isopropyl, allyl, butyl, isobutyl, sec-butyl, pentyl and hexyl) and some related compounds were prepared from L-cystine. L-5-Propylthiomethylhydantoin S-oxide (L-(±)-PHSO) was further split into L-(+)-PHSO and L-(-)-PHSO. L-5-Alkyl- and alkenylthiomethylhydantoin S-oxides exhibited antimicrobial activities, and L-(±)-PHSO and L-5-isopropylthiomethylhydantoin S-oxide were most active against Escherichia coli AHU 1041. There was no difference in activity between the two stereoisomers, L-(+)-PHSO and L-(-)-PHSO. Yeasts were much less sensitive to L-(+)-PHSO than bacteria. Although (±)-PHSO had potent inhibitory action against E. coli, the deoxy compound, L-5-propylthiomethylhydantoin did not have any activity and the S, S-dioxide had only a weak activity. Both N-carbamoyl-L-cysteine and its sulfoxide had no inhibitory action. From these results it has been suggested that the structure required for antibacterial activity involves both hydantoin ring and sulfoxide function.

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The structure-activity relationships of antibacterial L-5-alkylthiomethylhydantoin S-oxides and related compounds prepared were examined. S-Propyl-L-cysteine-S-oxide, its N-carbamoyl derivative and dl-3-alkylthio-2-methylpropionamide S-oxides which do not have hydantoin ring exhibited far less activities. 5-Alkyl- and alkenylthiomethyl-5-methylhydantoin S-oxides and 5-alkylthioethylhydantoin S-oxides bearing hydantoin structure did not have either any appreciable activity. From these results, it has strongly been suggested that the structure required for antibacterial activity is summarized as follows: (1) Hydantoin ring and (2) sulfoxide function should be necessary, (3) the hydrogen atom on the 5-C of the hydantoin ring is essential, and (4) the methylene-unit between the sulfur atom and the hydantoin ring is not two (or more), but one.

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Microdetermination of cartap hydrochloride 2-dimethylaminotrimethylene S, S′-bis(thiocarbamate) hydrochloride in soil was described. Cartap hydrochloride was adsorbed to soil with the effect of functinal groups in the structure. In proposed paper, cartap hydrochloride was extracted from soil at 65°C with 0.1N HCl containing 1.5% L-cysteine hydrochloride. The extract was hydrolyzed with 1.5% NH₄OH and oxidized with air to give nereistoxin(4-dimethylamino-1, 2-dithiolane). EPD-gas chromatography using sulfur mode was used to determine cartap hydrochloride without any interference. The minimum detection limit of nereistoxin by this method was 1ng corresponding to 0.005ppm in 20g of soil. The overall average recoveris from alluvial soil and volcanic ash soil were 96.8% and 98.0%, respectively. This conventional method will be useful for the residue analysis of cartap hydrochloride in soil.

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Absorption and translocation of 2-dimethylaminotrimethylene SS′-bis (thiocarbamate) (cartap) in plant were investigated. ³⁵S-Labeled cartap hydrochloride was applied to water culture of rice plant and the plant was subjected to autoradiography. Radioactive ³⁵S-compounds (³⁵S), i. e., ³⁵S-labeled cartap and its degradation products, absorbed from the roots or sheath were distributed throughout the whole plant within an hour. During subsequent cultivation in a solution not containing cartap, they were translocated to the top of the leaves and to the root. In an experiment on an injured plant by rice stem borer (Chilo suppressalis), ³⁵S was distributed equally to injured parts of the leaf, probably through the spongy parenchyma. ³⁵S, applied to the leaf blade by painting, was also transported to the whole leaf especially concentrated in the leaf sheath. From the extract of leaves and roots, 4-dimethylamino-1, 2-dithiolane (nereistoxin) and a small amount of 4-dimethylamino-1, 2-dithiolane 1-oxide (nereistoxin monooxide) were detected by thin layer chromatography. After 7 days of culture, most of the radioactivity was detected as nereistoxin, and cartap was hardly detected in any fractions.

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The method of the systematic identification and determination of pesticides was attempted by a combination of column, thin-layer and gas chromatography. Many kinds of pesticides were classified into six divisions and twenty two groups by thin-layer chromatography (tlc), and further divided into six fractions corresponding to divisions by column chromatography. In this paper, in order to apply this systematic method to the determination of pesticide residue in crops, food products or soils, an extract procedure, solvent partitioning and Florisil column cleanup procedures were decided with feed stuff-corns, which had some difficulty in analysis because of being rich in oils and coloring materials. Furthermore, recovery experiments at the level of residue analysis were performed to evaluate the efficiency of this systematic method. Fifteen pesticides in the First and Second Divisions containing tetrasul, heptachlor, quintozene, CNP, chlorpyrifos and nitrogen, etc. were mostly eluted into Fractions I and II from a silica column, respectively, and recovered approximately 100%. Twelve pesticides in the Second Division containing trifluralin, leptophos, dichlofenthion, dichlobenil and chlorfenson, etc. were mostly eluted into Fraction II and recovered more than 90%, except for chlorothalonil.

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After treating rice plants by submerged application with probenazole no changes were noted in the siliciferous cells in the leaves, no morphological changes in the leaf tissue and no anti-fungal activity in leaf exudates were detected. When rice plants were treated by submerged application of probenazole and subsequently inoculated with the blast fungus (Pyricularia oryzae CAVARA) peroxidase activity (oxidation of phenolic substances) increased and an anti-conidial factor in the rice leaf increased. Also the increase of the factor was observed in rice plants treated by the chemical but not inoculated. A part of the appearance of induced resistant characteristics were thought to be similar to a reaction of resistant rice plant. The induction of resistant characteristics were largely inhibited by a heat shock upon rice plant indicating that the event was host mediated reaction. Probenazole (submerged application) appears to control the blast disease in rice by a combination of the events, such as inhibiting sensitive stages in the life cycle of the blast fungus and also activating the host defence.

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Residues of 3, 3′-dimethyl-4-methoxybenzophenone and its metabolite 3, 3′-dimethyl-4-hydroxybenzophenone (OH metabolite) in soils and crops were investigated by means of the gaschromatograph with ECD. The OH metabolite was acetylated with acetic anhydride and pyridine for analysis with GC-ECD.
In upland soil and submerged soil, the half-lives of methoxyphenone were 23-30 days and 7-10 days, respectively.
The formation of OH metabolite reached as much as 1% of applied methoxyphenone in upland soil and 26-55% in submerged soil. Neither methoxyphenone nor OH metabolite were found in rice plant even at a treatment with twice amount of recommended dosage. The residue levels were below the detection limit in various crops except in carrot where 0.042ppm of methoxyphenone was detected.

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The uptake of ¹⁴C-DDT in cultured male germ cells derived from the cabbage armyworm, Mamestra brassicae L. was rapid for 3hr after treatment, but ¹⁴C-parathion was virtually not taken up by the cells. Approximately 40% of DDT taken up by the germ cells was removed from the cells by treatment with low concentrations (0.0001-0.01%) of the non-ionic detergent, Triton X-100. Only a small fraction of DDT taken up by the cells remained in the cytoskeleton structure resistant to 1% Triton X-100. Perhaps the conclusion to be drawn from the data presented in this paper is that DDT binds to outer membrane components of the germ cells.

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