Antioxidative and synergistic activities of 14 cysteine derivatives and 10 dipeptide derivatives with the sequences Cys (R)-Ser and Ser-Cys (R) were investigated, using an autoxidative system of linoleic acid, and the following results were obtained : 1) None of the tested compounds showed any marked antioxidative activity against autoxidation of linoleic acid. 2) In general, S-alkylcysteines were synergistically effective with both dl-α-tocopherol and dibutylhydroxytoluene (BHT). On the other hand, cysteine markedly increased POV of the system in the presence of BHT, while it showed synergistic activity toward α-tocopherol. 3) Blocking of the amino group of cysteine and S-alkylcysteines caused the loss of their synergistic activities, while blocking of the carboxyl group gave products with proxidative activity in the presence of antioxidants. 4) Both Cys (Bzl)-Ser and Ser-Cys (Bzl) showed synergistic effect nearly equal to their constituent amino acids. In analogy with S-alkylcysteins, blocking of the terminal groups, especially the carboxyl group, caused appreciable loss in the synergistic activities of the dipeptides, and a potent proxidative activity was observed with some blocked peptides including Ser-Cys (Bzl)-OBzl, BOC-Ser-Cys (Bzl)-OBzl, and Z-Cys (Bzl)-Ser-OMe. These results suggested that the synergistic action of cysteine derivatives and cysteine-containing peptides might be caused by cooperative action of blocked SH group and free NH₂ and COOH groups.

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Although consumer products containing organomercuric compounds have been banned in Japan since 1975, two kinds of organomercuric compounds were detected in imported shoe colors and shoe polishes, manufactured by Dylon International Ltd. in England and Kiwi Polish Co. in USA, respectively. The Dylon's compound was identified as phenylmercury by gas chromatography with electron capture detector. The Kiwi's compound was purified as the dithizonate by column and thin-layer chromatography, and its mass, proton magnetic resonance, and infrared absorption spectra were compared with those of the dithizonates of authentic organomercuric compounds. In this manner, the Kiwi's compound was identified as (3-chloro-2-methoxypropyl) mercury, which can be easily synthesized from allyl chloride and mercuric acetate in methanol.

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Photodieldrin formed by photoisomerization from dieldrin in wool was investigated. Photodieldrin was extracted by refluxing in methanol, purified by Florisil column chromatography after methanol was evaporated, and determined by gas chromatography with ⁶³Ni-ECD. The recovery of photodieldrin from wool and woollen sweaters was 96% and 97% for 1 ppm, and 101% and 101% for 10 ppm, respectively. The detection limit was 0.05 ppm. The ratio of photodieldrin to dieldrin in wool irradiated for 3 hr in the light, increased to more than 10%, and were 0.2%, 11.5%, and 17.5% for 6 hr in 300-600 lux, 4000-16000 lux, and 20000-86000 lux, respectively. The photodieldrin concentration in 5 kinds of commercial wool was 0.12-0.45 ppm and the ratio of photodieldrin to dieldrin was 0.092-1.1%.

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The effect of Aroclor 1248 (PCB) on the hepatopancreatic microsomal enzymes of carp was examined. The carp were fed a diet containing 250 ppm PCB for 7 days, and activities of NADPH-cytochrome c reductase, NADH-cytochrome b₅ reductase, aminopyrine N-demethylase, and aryl hydrocarbon hydroxylase, along with the amount of cytochrome P-450, cytochrome b₅, and microsomal protein increased significantly by ingestion of PCB. These results showed that Aroclor 1248 induced hepatopancreatic drug-metabolizing enzymes of carp which are similar to hepatic enzymes in mammals. The induction, however, seemed to be a mixed type, also induced by phenobarbital and 3-methylcholanthrene. By measuring the substrate-binding difference spectra of hepatopancreatic microsomes from the carp pretreated with Aroclor 1248, the PCB was found to be bound to cytochrome P-450 in a "modified type II" pattern as classified by Schenkman and others. The spectral changes induced by hexobarbital and aniline, and an increase in the δ-aminolevulinic acid synthetase activity also suggested that Aroclor 1248 increased the synthesis of cytochrome P-450 in the carp hepatopancreas. SDS-polyacrylamide gel electrophoresis, further demonstrated that the hepatopancreatic microsomes contained four kinds of heme protein and that the synthesis of the heme was induced by treatment of the carp with Aroclor 1248.

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The distribution pattern of cadmium in the liver, when renal damage occurred, was studied. Twenty Wistar male rats were divided into four injection dose groups of 0, 0.3, 1.0, and 1.5 mg of Cd (as CdCl₂) per kg of body weight. Subcutaneous injections were given 6 days a week. At 4 weeks, renal damage in the 1.0-and 1.5-mg dose groups occurred in the form of glucosuria, amino aciduria, or proteinuria. Amount of cadmium in the liver increased with dosage and appeared to reach a near-maximum in the 1.0-mg dose group. The hepatic Cd/Zn ratio increased in proportion to the tissue cadmium concentration but the plotted value in the 1.5-mg dose group was extremely higher than the value expected from the increase rate up to 1.0-mg dose group. The liver tissues were homogenized separately in 4 volumes of cold 0.25 M sucrose and the homogenate was centrifuged at 27000×g for 60 min. Increased dosage of cadmium resulted in an increase in the accumulation of cadmium in the 27000×g sediment, which may contain nuclei, mitochondria, lysosomes, and heavy microsomes. The 27000×g supernatant was fractionated on Sephadex G-75. In the 0.3-mg dose group, most of cadmium in the supernatant was bound solely to metallothionein, a low molecular weight protein. In the 1.0-and 1.5-mg dose groups, most of the increased cadmium was bound to metallothionein, but four additional fractions of cadmium appeared. One of them had properties similar to metallothionein. Metallothionein has a molecular weight of approximately 11000 and one of the additional fractions had a molecular weight of approximately 19900, and was assumed to be a dimer of metallothionein.

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Changes in th quality of domestic tap water during contact with model iron materials were investigated by chemical and instrumental analyses. When neutral chlorinated water was placed in contact with pure iron pieces at 20°, the concentration of residual chlorine (free and combined) and solved oxygen in the water decreased rapidly with time, and pH of the water was lowered in the presence of free chlorine, but rose in the presence of combined chlorine. Dissolution of Fe²⁺ from iron pieces into the water was accelerated by residual chlorine suddenly followed by oxidation of Fe²⁺ to Fe³⁺ precipitate. After disappearance of free Cl, however, presence of Fe²⁺ compounds in the water was found in a higher concentration. The rate of disappearance of free Cl, combined Cl, and dissolved oxygen in the water showed a linear relation with logarithm of each concentration. Rate constants for the disappearance of free Cl, combined Cl, and dissolved oxygen in the neutral water at 20° were about 3.2×10^-2, 2.7×10^-2, and 1.5×10^-2M/dm² (Fe)/min, respectively, when the concentration of these substances and SO₄^2- was less than 10 ppm.

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Several experimental conditions for the determination of estradiol (ED) and ethynylestradiol (EED) in cosmetics by high-speed liquid chromatography (HSLC) were developed. ED and EED were extracted from samples with dichloromethane, the extract was concentrated, placed on a silica gel column, and the column was washed with 1, 2-dichloroetane. The fraction eluted with ethyl acetate was concentrated and then ED and EED were determined by HSLC. The conditions for HSLC were as follows : Column, Zorbax SIL (250×2.1 mm, i.d.) ; mobile phase, tetrahydrofuran-hexane (1 : 9) ; flow rate, 0.75 ml/min ; column temp, room temp ; detector, fluorescence spectrophotometer (exciting wave length, 286 nm, fluorescence wave length, 307 nm). The detection limit of ED and EED was 0.005 μg/ml. The recovery of ED added to cosmetic samples was 92.2-96.0% and that of EED was 92.6-96.4%.

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Effect of isocyanuric acid on the stabilization of chlorine was examined in the presence of ammonia. The concentration of added chlorine was changed from 0 to 6 mg/l at the constant ammonia concentration (0.5 mg/l as NH₄⁺), and that of ammonia was changed from 0 to 10 mg/l as NH₄⁺ at the constant concentration of chlorine (1.74 mg/l) added. The added concentration of isocyanuric acid was 0 or 30 mg/l. In these systems exposed to the sun, time course of residual chlorine coucentration was measured at pH 4. Before the break point, chlorine, generally existing in the form of chloramine, was unstabilized by isocyanalic acid. Over the break point, chlorine, almost all existing in the form of free chlorine, was stabilized by isocyanuric acid. These facts seemed to suggest that the bactericidal properties of chlorine are affected by isocyanuric acid.

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Tetrahydrocannabinolic acid (THCA) in fresh cannabis leaves has been already known to convert to tetrahydrocannabinol (THC) by decarboxylation, and then to cannabinol (CBN) by further dehydrogenation. In the present study, THCA and THC in cannabis leaves under three different environmental conditions were determined by the combination of preparative thin-layer chromatography and gas-liquid chromatography. Over 50% of THCA in cannabis leaves under one kind of environmental condition was found to convert to THC in 5 days, while THCA was hardly converted to CBN or cannabinolic acid.

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