We investigated the state of water in frozen liquid foods, supposed to influence the performance of freeze-drying, by DSC. The amount of unfreezable water in milk was constant irrespective of the initial water content. As expected from the phase equilibrium, the water content of the non-ice part of CAS was constant among the samples with different initial water contents. The volume fraction of ice crystals, which should be known in the analysis of the freeze-drying rate, was significantly smaller at the low initial water content than the one usually estimated with the assumption that the water was all freezable.

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Cigarette smoke reduction due to a perforated mouthpiece tube was measured, and its results were compared with the reduction caused by conventionally vented acetate filters. The reduction of nicotine and tar increased with the ventilation rate through the perforated tube. In the absence of a filter material, the difference between the reduction of tar and nicotine was found to be greater than that observed for conventionally vented filters, and the concentration of nicotine in tar was enhanced. The reduction of carbon monoxide, carbon dioxide, acetaldehyde, isoprene and acetone were all proportional to the ventilation rate through the perforated tube. The presence of a filter material had no effect on the gas and vapor phase components.

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Using vented charcoal niters, the adsorption efficiencies of acetaldehyde, isoprene and acetone, the major components in the vapor phase of cigarette smoke, were studied. Filter ventilation was found to raise the adsorption efficiency of the adsorbent. The effect of increasing the ventilation rate through the filter was greatest for the adsorption of acetaldehyde. In order to clarify the effects of decreases of the flow rate and the concentration caused by ventilation, the adsorption by unvented charcoal filters under varied conditions was also measured. Although both raised the adsorptions of the three components, the lowered concentration was contributed to mainly by an increase of adsorption by the vented charcoal filters. Regardless of whether the filter was perforated or not, the adsorptions of the three components depended on the volume of the air drawn in at the top of the lighted end of the cigarette.

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Mutant strain ME544, which is able to grow on glycerol slowly, was derived from glycerolnegative mutant strain G011, which is a derivative strain of Cellulomonas sp. NT3060 and is defective in both the enzyme activities of glycerol kinase and glycerol 3-phosphate dehydrogenase. The mutant strain still lacked both the enzyme activities involved in the dissimilation of glycerol and had the same level of glycerol dehydrogenase activity as the parent strain. Dihydroxyacetone kinase activity in mutant strain ME544 was inducibly formed, reaching 4-fold the level in mutant strain G011 in glycerol medium. Thus, the mutant strain seemed to dissimilate glycerol by means of glycerol dehydrogenase followed by an increase in dihydroxyacetone kinase. Subsequently, a mutant strain, GP1807, which was resistant to the inhibition of growth on glycerol by 1, 2-propanediol, was derived from mutant strain ME544. Glycerol dehydrogenase activity of the mutant strain was amplified about 6-fold compared to that of the wild type strain.

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The effects of caseins on the Theological properties of κ-carrageenan'-calcium gel was investigated by measuring the gel breaking strength. The existence of β-casein in the system promoted the gelation of κ-carrageenan in the presence of calcium ion. Beta-casein increased the strength of calcium gels of κ-carrageenan with increasing NaCl concentration up to 80 mM and strengthened the κ-carrageenan-calcium gel at neutral pH. The values obtained from the slopes of the logarithmic plots of the gel strength versus concentration were 2.15 for κ-carrageenan gel and 2.27 for a β-casein-κ-carrageenan mixture gel, suggesting that β-casein may participate in the gelation of κ-carrageenan through the mediation of calcium ions.

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The formation of an intermediate product, which could easily give a radical product, in an early stage of the Maillard reaction was confirmed commonly occur in various sugar-amino compound systems, by detection of the N, N'-dialkylpyrazine cation radical generated on the addition of ascorbic acid (AsA) to the reaction mixtures. This intermediate was produced immediately after to glycosylamine formation, prior to Amadori rearrangement, and completely parallel to the formation of glyoxal dialkylimine, which was identified by TLC as a main component of the extract. Authentic glyoxal dialkylimine was shown to produce an identical radical on treatment with both reducing agents and acids instead of AsA. It was thus demonstrated that the intermediate is glyoxaldialkylimine and that acid hydrolysis followed by reduction is required for production of the free radical.

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Ascorbic acid-protein mixtures of low moisture content stored for 2-3 days in aerobic conditions at 60°C produced a red coloration, which was shown to have resulted from an amino-carbonyl reaction of oxidized ascorbic acid (dehydroascorbic acid, DHA) by the facts that DHA-casein or ovalbumin systems yielded a rapid red coloration in low moisture conditions as well as in an ethanol suspension. Zein showed only a weak red coloration with DHA. An apparent decrease in the free amino group, as determined by the TNBS method, was observed to be associated in parallel with the red pigment formation. The electrophoretic pattern of ovalbumin changed significantly upon incubation with DHA, together with the formation of the red pigment. The red pigment extracted from a DHA-casein system showed an absorption spectrum, TLC Rf value, and hydrolyzed products (DHA and scorbamic acid) identical to those of 2, 2'-nitrilo di-2(2)-deoxy-L-ascorbic acid mono ammonium salt, produced from DHA and amino acid. Formation of the red pigment was also observed in the reaction of DHA with N_α-acetyl lysine. These results indicate that the ε-amino group of lysine in protein can be attributed to the formation of a red pigment identical with NDA.

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Volatile flavor components of watermelon fruit (Citrullus vulgaris) were obtained by distilling juice under reduced pressure and extracting the resulting distillate with Freon-11. The volatiles were separated into acidic and neutral fractions and then analyzed by gas chromatography and gas chromatography-mass spectrometry.
Fifty-two compounds were found for the first time as flavor components of watermelon. Among them, the following compounds have not been previously reported as naturally occurring flavor components: 4-oxononanal and 2-hydroxy-, 2-pentyloxy-, 2-hexyloxy-, 2-octyloxy-, 2-nonyloxy-, 2-[(Z)-3-noneyloxy]-, 2-[(Z)-2-nonenyloxy]-, 2-[(Z, Z)-3, 6-nonadienyloxy]-, 2-benzyloxy-, and 2-phenetyloxy-5-pentyltetrahydrofurans.

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Screening of microorganisms producing a new kind of flocculating substance was carried out. A fungus that produced a large amount of a strong microbial cell flocculant was isolated from soil. The fungus was classified as a Paecilomyces species. The substance produced showed very interesting and unique flocculation characteristics. It could efficiently flocculate all tested suspended solids in aqueous solution, and flocculation was practically not affected by ionic strength, pH or temperature.
The influence of components of the culture medium upon the flocculant production by Paecilomyces sp. 1-1 was studied. Addition of hydrolysates of casein such as casamino acid and polypeptone stimulated the production of the flocculant. A high concentration of calcium ions also significantly increased the mycelial growth and the production of the flocculant. Under the optimum cultural conditions, a 500-fold dilution of the culture filtrate could efficiently flocculate and sediment E. coli cells.

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A new flocculant for microbial cells was purified by ethanol precipitation and gel chromatography from the culture fluid of Paecilomyces sp. I-1. Isoelectric focusing of the flocculant (PF-101) showed a single band at pH 8.5, and its molecular weight was estimated to be over 300, 000 daltons by the ultra-filtration method. The results of elemental analysis, the IR spectrum and investigation of the acid hydrolysate by gas and liquid chromatography and colorimetric analysis suggested that PF-101 was a polysaccharide composed of galactosamine. About 80% of the galactosamine residues were N-unsubstituted and 8% were N-acetylated. Studies on deaminative cleavage, periodate oxidation and Smith degradation suggested that the galactosamine residues were mainly linked by α (1→4)-linkages.

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Xylanase produced by E. coli HB101 carrying plasmid pCX311, which contains the xylanase A gene of alkalophilic Bacillus sp. strain C-125, was purified by ammonium sulfate precipitation, DEAE-cellulose column chromatography and Sephadex G-75 gel filtration. The purified enzyme had a molecular weight of 43, 000. The pH and temperature optima for its activity were 6-10 and 70°C, respectively. The enzyme retained full activity after incubation at 50°C for 10min. These enzymatic properties of the xylanase were almost the same as those of xylanase A. But this enzyme was less stable than xylanase A at low pHs. Furthermore, we could purify a larger amount of alkaline xylanase from E. coli than from alkalophilic Bacillus sp. strain C-125.

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Olive oil was hydrolyzed continuously at 40°C by Candida cylindracea lipase in a small hollow fiber bioreactor (total area of hollow fibers was about 0.11m²) in which the hollow fibers were made of microporous polypropylene. The lipase could be adsorbed easily onto oil-impregnated hollow fibers from its aqueous solution. The continuous feedings of olive oil inside the hollow fibers and of the buffer solution containing 18% glycerol as a stabilizer outside the hollow fibers were started after the enzyme-glycerol solution was removed from the bioreactor and the buffer-glycerol solution was added. An unvaried half life of 14 days of the adsorbed enzyme was observed when increasing amounts of the enzyme (1.0-5.0mg/ml) were put in, but its half-life was lowered to 6 days when the amount of the added enzyme was less (0.05 mg/ml). Free enzymes in the enzyme solutions with and without 18% glycerol retained their initial activities equally for at least 3 months at temperatures below 4°C. This suggests the feasibility of reuse of the enzyme-glycerol solution that was used in the preceding adsorption procedure after the solution was stored and supplemented with fresh enzyme. It was demonstrated by three successive cleanings and continuous hydrolyses that the used hollow fibers were regenerable. The productivity number was 0.81mg•(unit)^-1•h^-1, which was 26 times as great as that of the gel-entrapped lipase.

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A novel α-L-fucosidase was found in the culture broth of Fusarium oxysporum isolated from a soil sample when the fungus was cultivated on a liquid active sludge hydrolyzate medium. The enzyme was not found in the culture broth of the fungus grown on glucose medium. The α-L-fucosidase from the fungus was purified to homogeneity by polyacrylamide gel electrophoresis after ammonium sulfate fractionation and successive column chromatographies on DEAE-Sephadex A-50, hydroxylapatite, Sephadex G-150 and Con A-Sepharose 4B. The molecular weight was estimated to be about 80, 000 by gel filtration, and the optimum pH was found to be 4.5. The enzyme was relatively stable in the pH range of 4-8 and up to 45°C on 10min incubation. The Km value for p-nitrophenyl α-L-fucoside was 0.87mM. The enzyme showed a novel substrate specificity in that it could hydrolyze porcine mucin and blood group substances of human saliva besides nitrophenyl compounds. Such a specificity has not been found for any other α-L-fucosidase from various sources.

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Effects of various compounds on the dextransucrase (EC 2.4.1.5) from Leuconostoc mesenteroides was evaluated based on the two catalytic activities of enzyme, that is the hydrolase activity for the substrate, sucrose, and the transferase activity of a D-glucosyl group to an acceptor molecule. The effectors were grouped into six categories by their activation or inhibition of the sucrase and transferase activities of dextransucrase. Type I-A inhibited both activities, type I-B inhibited the sucrase activity, and type I-C inhibited the transferase activity. Type A-A activated both the hydrolase and transferase, and type A-B activated only the transferase. Antagonistic modulation (type IA-A), was shown by methyl α-D-glucoside and glycerol, which activated the sucrase and inhibited the transferase. A double reciprocal plot for dextran gave a biphasic pattern which led to Ki values for each limb. Based on the biphasic kinetics and the action of antagonistic effectors, the regulation of dextran synthesis was discussed.

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Oxime ethers containing a 4-phenoxyphenoxy group in the molecules were synthesized and their insect growth regulating (IGR) activities were studied. Of these new IGR's, propionaldehyde oxime O-2-(4-phenoxyphenoxy)ethyl ether and propionaldehyde oxime O-2-(4-phenoxyphenoxy)propyl ether were found to be most effective, having much higher activities than methoprene against larvae of Culex pipiens pollens and Musca domestica by the immersion method and medium method, respectively. In addition, the effects of steric isomerism of these compounds were examined; their IGR activities were found to have a close relationship to the juvenile hormone activity by the Galleria wax test.

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One hundred and nineteen strains of microorganisms (yeasts, bacteria, actinomycetes and fungi) were screened as to the hydroxylation of bicyclo[2.2.1]heptane-7-carboxylic acid, bicyclo[2.2.1]hept-2-ene-7-syn-carboxylic acid, and their methyl esters. Several species belonging to the genera, Bacillus, Streptomyces, Penicillium, Aspergillus, Absidia, Beauveria, Cunninghamella, Drechslera, Mucor and Chaetomium, were found to asymmetrically hydroxylate some or all of the substrates. Bacillus thuringiensis and Aspergillus awamori were the most effective microorganisms for obtaining the chiral products, (1R)-2-hydroxy acids or esters, with enantiomeric purities of 75-90% e.e., which are potential intermediates for (-)-methyl jasmonate or natural prostaglandins.

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Some microorganisms, including some bacteria isolated from soil, were found to secrete an extracellular soymilk-clotting enzyme. Among them, strain No. K-295G-7 showed the highest soymilk-clotting activity and stability of the production of the soymilk-clotting enzyme. The enzyme system (culture filtrate) coagulated protein in soymilk, a curd being formed at pH 5.8-6.7 and at 55-75°C. The optimum temperature for the soymilk-clotting activity was 75°C and the enzyme system was stable at temperatures below 50°C down to 35°C. About 80-100% of the original activity remained after 1hr at pH 5-7 and 35°C.

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The spore coat protein of Clostridium perfringens type A was solubilized from intact spores by treatment with a mixture of sodium dodecyl sulfate (SDS) and dithiothreitol (DTT) at alkaline pH. About 35% of the total dry weight of spores was extracted with this treatment. The extracted protein was partially purified by gel filtration. The major component (Fr-B1) is rich in glutamic acid and aspartic acid, as well as half-cystine. SDS-polyacrylamide gel electrophoresis analysis of the Fr-B1 showed a major polypeptide band of a molecular weight of 17, 000.

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Cultured malt broth of Fusarium poae has a strong fruity odor mainly due to lactones: γ penta-, γ hexa-, γ hepta-, γ octa-, γ nona-, γ deea-, γ undeea-, γ dodeca-, cis-6-dodecen-4-olide and δ decalactones. They were identified after gas chromatography and mass spectrometry by comparison of retention data and odors with those of authentic samples. cis-6-Dodecen-4-olide is the most abundant lactone (2 mg/liter) and is responsible for the predominant canned peach-like aroma.

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Two amino acid derivative antibiotics, hadacidin and duazomycin A, were isolated as inhibitors of de novo starch synthesis in excised leaf segments from culture filtrates of Penicillium No. 467 and Streptomyces No. 317, respectively. In addition, azaserine, 6-diazo-5-oxo-L-norleucine (DON), and trifluoro-DL-methionine were found to be potent inhibitors among about 70 kinds of commercial amino acid derivatives. These amino acid derivatives inhibited de novo starch synthesis at concentrations ranging from 1 to 10ppm but did not inhibit photosynthetic oxygen evolution at a concentration of 100ppm. The inhibition caused by these diazo compounds was reversed by a supplement of L-glutamine. With hadacidin and trifluoro-DL-methionine, however, the reversal was not observed upon the addition of L-aspartic acid or L-methionine, respectively. Among these active compounds, hadacidin was herbicidal against lettuce and barnyard millet by foliar treatment at a concentration of more than 1000ppm.

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The properties of uridine phosphorylase (UPase) and purine nucleoside phosphorylase (PNPase) at high temperature were investigated. Both enzymes were found to be distributed in a wide range of bacteria and were partially purified from Enterobacter aerogenes AJ 11125 by heat treatment, ammonium sulfate fractionation and column chromatographies onDEAE-cellulose and Sephadex G-150. The UPase Was purified 109-fold, and it showed an optimum pH of 8.5 and optimum temperature of 65°C, and activity toward uridine, 2'-deoxyuridine, thymidine and uracil arabinoside but not cytidine. The Km values of UPase for uridine were 0.7 mm at 40°C and 1.8mM at 60°C. The PNPase was purified 83-fold, and it showed an optimum pH of 6.8 and optimum temperature of 60°C, and significant activity toward purine arabinosides as well as purine ribosides. The Km values of PNPase for inosine were 0.8 mM at 40°C and 2.2 mM at 60°C.

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The sensitivity of cultured insect cells to a moulting hormone depended on their origin. Cell proliferation of cell-line C6/36, which originated from an Aedes albopictus larva, was suppressed by high concentrations of 20-hydroxyecdysone but was greatly promoted by low concentrations. Similar phenomena were observed with extracts of cedar and pine pollen. By employing the C6/36 cell-line for the screening of insect growth regulating substances, a highly active cell-growth promoting substance was found in a bovine pancreas extract. When 1 ppt of the partially purified substance was added to 2.5% fetal calf serum, the growth of cells was so greatly promoted that it was more than equal to that in the standard medium containing 10% of the serum.

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An exocellular γ-glutamyl arylamide-hydrolyzing enzyme was produced by a Bacillus sp. in L-glutamate-containing medium. This enzyme was a tetrameric simple protein composed of two heavy subunits (Mr 56, 000) and two light subunits (Mr 46, 000). It hydrolyzed γ-amido, acyl and aryl bonds in L- and D-glutamyl compounds, and the activity on L-glutamic acid γ-p-nitroanilide was inhibited by the addition of glutamate and γ-glutamyl compounds but not by α-glutamyl compounds. The activity was stimulated by various dipeptides but not by free amino acids. L-Alanine, glycine, L-serine and L-cysteine inhibited the enzyme competitively. Addition of hydroxylamine had no effect on the activity.

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N-Acyl- and N-sulfonyl-N-(2, 3-epoxypropyl)benzenesulfonamide derivatives were synthesized and their herbicidal activities were tested against barnyardgrass and rice plants by the pot and the petri dish tests in order to examine the structural requirements for herbicidal activity in N-(2, 3-epoxypropyl) benzenesulfonamide derivatives. The N-sulfonylbenzenesulfonamide derivatives exhibited higher activity against barnyardgrass than the N-acylbenzenesulfonamide derivatives, and were found to be as active as N-(2, 3-epoxypropyl)-N-(α-methylbenzyl) benzenesulfonamide. Some of the N-sulfonylbenzenesulfonamide derivatives showed high selectivity towards barnyardgrass and rice plants at their germination stage.

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The change in the levels of endogenous cytokinins in the shoot and grain of rice (Oryza sativa L. japonica cultivar Nihonbare) during its growth and development was followed by selected ion monitoring using deuterium-labelled internal standards. Five cytokinins, zeatin (Z), cis-Z, ribosylzeatin (RZ), cis-RZ and 6-(3-metliyl-but-2-enylamino)purine riboside were detected in the shoot, root and ear of rice. The maximum contents of RZ and Z in the shoot and root were found at the maximum tillering stage. In the ear, the levels of Z and RZ changed markedly. It is therefore suspected that RZ and Z play some roles in the tillering and seed growth in rice.

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Quinoxaline derivatives from disaccharides (isomaltose, maltose, laminaribiose, trehalose and sucrose) and o-phenylenediamine (OPD) under weakly acidic reflux conditions were subjected to GLC and GC-MS analyses.
Three high-molecular-weight quinoxaline derivatives (IA-I, -II and -III) were obtained from isomaltose in a yield of 90%, indicating no splitting of the glucosidic linkages. Both low- and highmolecular-weight quinoxaline derivatives were obtained from 5 mM maltose. From 50 mM maltose, a low-molecular-weight quinoxaline, GA-I, was obtained predominantly. Quinoxalines from laminaribiose were both high (LA-I and -II) and low (ATBQ, GA-I, G-1 and GA-II) molecular-weight derivatives, in yields of 18% and 48%, respectively. LA-I and -II were stereoisomers, at the C-3 position, of laminaribiose. Trehalose gave no quinoxalines, and sucrose gave only small amounts of low-molecular-weight quinoxalines.
From these results, we found that 1, 6-linkages of the disaccharides used are most resistant to the OPD degradation, followed by the 1, 4- and 1, 3-linkages, in that order. Possible pathways for the formation of quinoxalines are proposed.

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An enzymatically modified gelatin with covalently attached leucine dodecyl ester, referred to as EMG-12, was used as a surfactant to prepare emulsions with different properties by changing the surfactant concentration, oil volume fraction, and pH in the water phase. The emulsions generally resisted the freezing of their constituent bulk water at approximately -10°C, but similar emulsions produced with soy protein isolate, casein, or Tween-80 as control agents were less resistant. The freezing (or unfreezing) of the bulk water in these emulsions depended on the kind of agent used, not on the emulsion properties such as average area of the oil/water interface, stability against coalescence, and stability against creaming. The emulsion produced with EMG-12, like that produced with polyglycerol stearate, tended to maintain its unfrozen state even in the presence of silver iodide crystals added as heterogeneous ice-nuclei. The significance of producing such an antifreeze emulsion is discussed from the standpoint of cryopreservation of cold-sensitive food and biological systems.

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Modification of tryptophan residues in castor bean hemagglutinin (CBH) with N-bromosuccinimide (NBS) was investigated in detail. Tryptophan residues accessible to NBS increased with lowering pH and six tryptophan residues/mol were oxidized at pH 3.0, while two tryptophan residues/mol were oxidized at pH 5.0. From the pH-dependence curve for tryptophan oxidation, we suggest that -the extent of modification of tryptophan in CBH is influenced by an ionizable group with pK_a=3.6. The saccharide-binding activity was decreased greatly by modification of tryptophan concomitantly with a loss of fluorescence. A loss of the saccharide-binding activity was found to be principally due to the modification of two tryptophan residues/mol located on the surface of the protein molecule. In the presence of raffinose, two tryptophan residues/mol remained unmodified with retention of fairly high saccharide-binding activity. The results suggest that one tryptophan residue is involved in each saccharide-binding site on each B-chain of CBH.

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