Avoidance tests to seven anionic surfactants were conducted using medaka (killifish, Oryzias latipes) in a small chamber system with a bisymmetric parallel-flow. The avoidance ratio (AR, percentage of time spent by a fish in the clean water area of the test-trough in a 5 minute period) and AR₆₅ (95% confidence limit), which is the minimal avoidance concentration of a chemical when the AR is 65% were calculated and used as quantitative parameters of fish avoidance behavior. Patterns of avoidance ratio curve against the various anionic surfactants were similar to each other. AR increased as the concentration of the test surfactant increased, and at a certain concentration AR began to decrease sharply, and finally the medaka did not avoid the surfactant. AR₆₅ of the tested surfactants were: AS (7.1 μg/liter) < LAS, ABS < pure reagent-AES, formulation-AES < sodium laurate < sodium stearate < sodium palmitate (285 μg/liter). AR₆₅/48 hr-LC₅₀ ratios were 0.0002_??_0.002. No relationship was found between the avoidance concentration and the acute lethal concentration.

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Tripeptidase [EC 3. 4. 1.3] in the cytosol fraction of hog small intestinal mucosa was purified by DEAE-cellulose column chromatography, Cellulofine GC-100 gel filtration, preparative electro-focusing, Sephadex G-150 gel filtration and affinity chromatography using Octylamino Sepharose 4 B. The overall procedure gave on approximately 12-fold purification, and the purified enzyme was found to be homogeneous by polyacrylamide gel electrophoresis. The molecular weight of this enzyme was estimated to be about 45, 000 by gel filtration. The optimum pH, optimum temperature and apparent Km value of this tripeptidase were 7.5, 45°C and 0.927 mM, respectively. Inhibition was found by the addition of pCMB and Hg²⁺, while no inhibition was found by EDTA and other metal chelating agents. Among the several tripeptides tested, Leu-Gly-Gly and Ala-Gly-Gly were hydrolyzed rapidly but Gly-Gly-Gly hydrolyzed slowly. No activity was found against dipeptides, acyltripeptide and tripeptideamide.

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Five glycosylsterols, one glycosylceramide and two glycosylglycerides were isolated from corn seeds. The main glycolipids were monoglycosylsterol, monoglycosylceramide, monoglycosyldiacyl-glycerol and diglycosyldiacylglycerol in decreasing order.
Glycosylsterols consisted of acylmono-, mono-, di-, tri- and tetraglycosylsterol. The principal classes were the first two, the representative molecular species of which were characterized as 6'-palmitoyl-3-O-glucosyl-sitosterol and 3-O-glucosyl-sitosterol, respectively.
Monoglycosylceramide was separated as sphingoglycolipid. The main molecular species were shown to be 1-O-glucosyl-N-2'-hydroxy-arachidoyl-4, 8-sphingadienine and 1-O-glucosyl-N-2'-hydroxy-lignoceroyl-4-hydroxy-8-sphingenine.
Glycosylglycerides obtained were mono- and diglycosyldiacylglycerol. The principal molecular species were speculated to be 1-oleoyl-2-linoleoyl-3-O-galactosyl-sn-glycerol and 1-linoleoyl-2-linolenoyl-3-O-digalactosyl-sn-glycerol, respectively.

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Volatile compounds of green teas fired in a firing machine at 130°C for 10, 20 and 30min were prepared by vacuum distillation and analyzed by GC and GC-MS for comparison of volatile compounds of non-fired green tea (raw tea).
The major aroma compounds of raw tea decreased slightly during the firing process. The off-flavor compounds found in stored green tea decreased remarkably during the firing process. Pyrazines, pyrroles, furans, 3, 7-dimethyl-1, 5, 7-octatriene-3-ol and phenylacetaldehyde were produced during firing. Methylpyrazine, 2, 5-dimethylpyrazine, 1-ethylpyrrole-2-aldehyde, 2-acethyl-pyrrole and furfural increased remarkably after firing for 30min, and these pyrazines and pyrroles might be important volatiles in the formation of firing tea flavor. The amounts of 3, 7-dimethyl-1, 5, 7-octatriene-3-ol and phenylacetaldehyde were higher in fired low grade tea compared with high and medium grade tea.

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The specific heat of Japanese rice at different stages of milling was measured. The specific heat of rough rice was measured by an adiabatic calorimeter, husked rice by a modified ice calorimeter and fully milled rice by a twin calorimeter.
Their specific heat values were slightly lower than foreign rices. The relationship between the specific heat of rough rice and moisture content is indicated by the following regression equation: C=0.0112 W+O.217, moisture content 9.8% to 23% where C is specific heat (cal/g °C) and W is moisture content (%). For husked rice and fully milled rice, measurements were made in lower ranges of moisture content. The relationship between the specific heat and moisture content was indicated by two segments with one break, and the regression equations were:
For husked rice (Nihonbare),
C=0.117+0.240,
moisture content below 9.2%,
C=0.00805 W+0.272,
moisture content 9.2% to 14%, For husked rice (Koshihikari)
C=0.0109 W+0.234,
moisture content below 9.2%,
C=0.00803 W+0.262,
moisture content 9.2% to 15%, For fully milled rice (Koshihikari)
C=0.0121 W+0.217,
moisture content below 9.4%,
C=0.00801 W+0.255,
moisture content 9.4% to 15.5%.

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The fatty acid composition of neutral lipids and phospholipids of fish oils extracted from light and dark muscles was determined by GLC. The neutral lipid-to-phospholipid ratio of the determined fish oils was almost 8:2. Palmitic acid (C_16:0) and oleic acid (C_18:1) in neutral lipids and docosahexaenic acid (C_22:6) in phospholipids were the dominant fatty acids. The content of total polyunsaturated fatty acids was about 33% in neutral lipids and 60% in phospholipids.
The total polyunsaturated fatty acid-to-total saturated fatty acid ratios was about 1.3 for marine fish and less than 1.0 for fresh water fish. Of polyunsaturated fatty acids, docosahexaenic acid (9_??_18%) and eicosapentaenic acid (6_??_10%) were prominent.

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[in Japanese]

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