The selectivity coefficients of 16 amino acids for the ammonium form of a strong cation exchange resin (8% divinylbenzene (DVB)) were determined, using the mass action law, and were found to be correlated with various physicochemical parameters through trials of multiple regression analysis. Good relationships were obtained between selectivity coefficients and physicochemical parameters, such as the partition coefficient in octanol/water of amino acids and molecular weight. When the amino acids were divided into three groups (hydrophilic, hydrophobic and basic), the molecular weights of amino acids in the respective groups showed good relationship with the selectivity coefficients of the respective amino acids (regression coefficient: 0.94-0.96). A multiple regression equation was found to express the selectivity coefficient for each amino acid as a function of three parameters (partition coefficient, hydration number and partial molar volume). These results show that the selectivity coefficient of an amino acid is extensively affected by the hydrophobic interaction, together with the molecular size.

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Volatile flavor compounds of seven kinds of dried and smoked fish, such as soda-katsuobushi (dried frigate mackerel), mold-cultured soda-katsuobushi, sababushi (dried mackerel), mold-cultured sababushi, magurobushi (dried tuna), muroajibushi (dried mackerel scad) and katsuobushi (dried bonito) were analyzed, and the differences in flavor composition among these fishes were studied.
Each aroma concentrate obtained by simultaneous distillation-extraction was fractionated into acidic and neutral fractions. The neutral fraction was further fractionated by silica gel column chromatography. All fractions were analyzed by gas chromatography and gas chromatography-mass spectrometry.
Then the analytical data were studied by hierarchial cluster analysis. From the results of cluster analysis and sensory evaluation, it was concluded that katsuobushi, soda-katsuobushi, and magurobushi were quite similar in sensory characteristics and flavor composition.

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Close to 15% of the karatasin proteinase activity in the fruit juice of Bromelia plumieri (karatas) is present outside dialysis Visking tubing in 7 days in 0.2 M acetate buffer (pH) 3.5 or 6.5) containing phenyl mercuric acetate. The small proteinase(s), distinct from the 85% activity in juice due to non-dialysable karatasin with a reported M_r of 24, 868, separates across Spectrapore (13 kDa) membranes but not across Spectrapore with 3.5 kDa average pore diameter. The dialyzed proteinase is named karatasin-D (K-D). Purified non-Dialysable karatasin can be dissociated to what seems to be K-D by incubation in a buffer solution, containing SDS and 2-mercaptoethanol with phenyl mercuric acetate, in dialysis experiments for 8 days at room temperature using Spectrapore 13 kDa tubing.
Thus, native karatasin in B. plumieri fruit juice seem to be the result of association of 2 small molecular mass K-D subunits, linked together by disulfide bonds and electrostatic forces, in equilibrium with small amounts of free K-D molecules. The amino acid composition and partial sequence of karatasin up to the 14th position from the amino terminus have discrete analogies with papain and with stem bromelain.

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The relationship between membrane binding and phosphorylation by protein kinase C (PKC) of acylated protein was examined using chemically acylated lysozyme and phosphatidylserine (PS)-containing dipalmitoylphosphatidylcholine (DPPC) vesicles. Lysozyme monoacylated with a short chain fatty acid such as caproic acid (C₆) was neither bound nor phosphorylated similarly to native lysozyme. With monoacylated lysozyme with the longer chain fatty acids from caprylic acid (C₈) to myristic acid (C₁₄), on the contrary, both membrane binding and phosphorylation increased linearly as the fatty acid chain length increased and reached the maximum value with monomyristoylated lysozyme. The similarity of the profiles in increase in membrane binding and phosphorylation indicated that these two phenomena might be concomitant events. It was also found that the phosphorylated monomyristoylated lysozyme was detected exclusively in the vesicle fraction and the phosphorylation of unbound monomyristoylated lysozme was negligible. These data suggest that the membrane binding mediated by protein acylation directs the protein phosphorylation by PKC.

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A yeast strain, isolated from the exudate of a tree, accumulated biosurfactants abundantly when grown on soybean oil as the sole carbon source. The biosurfactants were found to be a mixture of 4 mannosylerythritol lipids, including two new mannosylerythritol lipids as major components. The major components, which amounted to about 80% of the total lipids, were determined to be 4-O-(di-O-acetyl-di-O-alkanoyl-β-D-mannopyranosyl)-erythritol and 4-O-(mono-O-acetyl-di-O-alkanoyl-β-D-mannopyranosyl)-erythritol. The yeast strain was identified as Candida antarctica (Goto et al.) Kurtzman et al.

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Three tested stock-strains of Candida antarctica were found to produce biosurfactants, i.e., mixtures of 4 mannosylerythritol lipids. They were similar to those produced by isolated strain T-34, but differed in the compositions of the mixtures of the lipids. Strain T-34 was the best producer of the lipids as to total amounts. The strain produced the lipids from different vegetable oils, but failed to produce them from n-alkanes or carbohydrates. The supplementation of yeast extract increased the yield of the lipids. Under the optimal conditions in a shake culture, the concentration of the total lipids amounted to about 40g/1 after 8 days. During the cultivation, the composition of the mixture of the lipids was found to change.

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In order to develop a practical debittering method for amino acids and peptides, several debittering methods were studied. The authors found that hooking acidic amino acids to and acetylation of bitter amino acids is very effective to remove the bitterness from their concentrated solution. For debittering by mixing with additives, skim milk and other peptide compounds were effective. Acidic amino acids were also effective to reduce the bitterness. Gelatinized starch was found to be useful for debittering because it takes bitter substances into its net structure.

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Immobilized cultured cells of Lavandula vera accumulated blue pigments in the culture medium in the presence of L-cysteine when the cells were cultivated under illumination, while brown pigments were accumulated in the dark. Several components of the brown pigments turned blue spontaneously on incubation in the culture medium without the plant cells, Fe³⁺ ion being found to play an important role in this conversion. One of the main components of the brown pigments, which is a precursor of the blue pigments, was deduced to be a novel compound, 1-methylethyl 3, 4-dihydro-7, 8-dihydroxy-5-methoxy-3, 10-dimethyl-4-oxo-4H-naphtho[2, 3-b]pyran-3-butanoate.

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The β-fructosidases from the thermotolerant fungus, A. ficuum, were characterized. All were active as to inulin and sucrose hydrolysis with different specificity constants (k_cat/Km). The enzymes were classified according to the ratio (α) of the specificity constants for inulin (I) and sucrose (S). The invertase showed an α value of lower than one, while the inulinases had α values of higher than one. The a ratio is proposed for the classification of β-fructosidases into the inulinase (EC 3.2.1.7) and invertase (EC 3.2.1.26) groups. The amino acid composition, pH and temperature profiles, ultracentrifugation analysis results and effects of metal ions and effectors were studied. The data confirmed the preceding classification based on the I/S ratio, on the mode of action of inulinases (exo or endo) during inulin hydrolysis and on the molecular properties of the proteins.

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The effects of metal ions on DNA damage induced by hydrogen peroxide were investigated using two methods, agarose-gel electrophoretic analysis of supercoiled DNA and sequencing-gel analysis of single end-labeled DNA fragments of defined sequences. Hydrogen peroxide induced DNA damage when iron or copper ion was present. At least two classes of DNA damage were induced, one being direct DNA-strand cleavage, and the other being base modification labile to hot piperidine. The investigation of the damaged sites and the inhibitory effects of radical scavengers revealed that hydroxyl radical was the species which attacked DNA in the reaction of H₂O₂/Fe(II). On the other hand, two types of DNA damage were induced by H₂O₂/Cu(II). Type I damage was predominant and inhibited by potassium iodide, but type II was not. The sites of the base-modification induced by type I damage were similar to those by lipid peroxidation products and by ascorbate in the presence of Cu(II), suggesting the involvement of radical species other than free hydroxyl radical in the damaging reactions.

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Saponins are bioactive substances with physiological activities and bitter taste. We investigated the distributions of saponins in soybean plants. Acetyl-soyasaponins A₁ and A₄ occur only in seed hypocotyls of soybean plants. Soyasaponin I was detected in all organs of the plant. However, soyasaponin I levels in plant showed very heterogenous distributions, for example, stem and main root had very low soyasaponin I levels, but nodule and leaf had higher levels.

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Three endo-β-1, 4-glucanases (CMCases E-I, E-II and E-III) from Bacillus sp. KSM-522 were purified to homogeneity by repeated chromatography on DEAE Bio-Gel A. The molecular weights were 78, 000 for E-I, and 61, 000 for both E-II and E-III, as judged on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The optimum pH values for activity and isoelectric points were around 6 and 4.4 for E-I, and 7-10 and 3.5 for both E-II and E-III, respectively. These CMCases hydrolyzed CMC in a similar random fashion. The alkaline CMCases, E-II and E-III, were not distinguishable from each other with respect to temperature-activity curves, temperature-stability curves, substrate specificity, patterns of action on cellooligosaccharides, susceptibility to inhibitors or effects of metal ions.

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Three strains of alkalophilic Bacillus, KSM-19, KSM-64 and KSM-520, were isolated which produced alkaline cellulases suitable as additives for improving the efficiency of detergent products. Their activities were not inhibited at all by metal ions or various components of laundry products, such as surfactants, chelating agents and proteinases. The enzyme preparations showed strong activities toward carboxv methyl cellulose, the optimum pHs being 8.5-9.5 and the optimum temperatures about 50°C.
Maximum growth of the isolates was observed at an initial pH of 8.5-9.5; slight growth occurred at neutral pH. Production of the alkaline cellulases required the presence of carboxymethyl cellulose, and it was controlled by a mechanism involving catabolite repression and induction. Two strains, KSM19 and KSM-64, produced alkaline lichenan-hydrolyzing enzymes.

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A novel endo-β-N-acetylgIucosaminidase acting on complex type sugar chains of glycoproteins was found in the culture broth of a fungus isolated from soil and identified as Mucor hiemalis f. hiemalis on the basis of various characteristics. The endo-β-N-acettylglucosaminidase, named Endo-M, was purified to almost homogeneity by polyacrylamide gel electrophoresis involving ammonium sulfate fractionation, and column chromatographies on DEAE-Sepharose CL-6B, Sephadex G-200, hydroxylapatite, TSK-gel HW-65F and Con A-Sepharose 4B. The molecular weight of the enzyme was estimated to be about 95, 000 by gel chromatography. The optimum pH was found to be 6.0-6.5 and the enzyme was stable in the pH range of 7 to 8. The enzyme showed high activity on dansyl ovalbumin glycopeptide, and also could act on dansyl transferrin glycopeptide and dansyl asialotransferrin glycopeptide containing biantennary complex type sugar chains. The Km value for dansyl asialotransferrin glycopeptide as the substrate was 2.0×10^-3M. The enzyme released complex type sugar chains from intact asialotransferrin without the addition of any detergent and the liberated sugar chains were identified by chromatography on a Bio-Gel P-4 column, calibrated with markers of known structure, and ¹H-NMR analysis.

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A functional ovalbumin-dextran conjugate was prepared by dry-heated storage at 60°C and 65% relative humidity for 3 weeks. The emulsifying properties of the ovalbumin-dextran conjugate were about three times higher than those of an ovalbumin-glucose conjugate. SDS-electrophoresis patterns showed that the ovalbumin-dextran conjugate obtained by dry-heating was not as polydispersed as that obtained by cyanogen bromide-activated dextran. The average molecular weight of the ovalbumin-dextran conjugate was about 200, 000. The excellent emulsifying properties of ovalbumin-dextran conjugate were maintained even at pH 3 and were further improved at pH 10. In addition, the emulsifying properties of the ovalbumin-dextran conjugate were greatly enhanced by preheating the conjugate at 100°C. Thus, it is suggested that an ovalbumin-dextran conjugate prepared by controlled dry-heating can be used as a macromolecular emulsifier for food applications.

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The rate of whole body protein synthesis in mice was obtained by a newly modified large dose method. A large amount of alanyltyrosine was injected intraperitoneally together with a tracer dose of [¹⁴C]tyrosine into mice. The animals were sacrificed at 10, 17, 24 and 31 min after the injection. The specific radioactivity of free tyrosine in the whole body was slightly higher than in the serum at 10 min and then decreased linearly. The two straight lines from the serum and whole body crossed each other at about 20 min after the injection. The specific radioactivity of the bound tyrosine in the whole body homogenate increased linearly from zero. Assuming the specific radioactivity of free tyrosine at the crossover point represents that of the site of protein synthesis, we estimated the fractional rate of whole body protein synthesis in mice receiving diets containing egg white hydrolysate, or an amino acid mixture simulating egg white protein, by measuring the specific radioactivity of the free and protein-bound tyrosine at 20 min after the injection in another set of experiments. The fractional synthesis rate of whole body protein was 26.5% per day in the peptide-fed animals, and 19.7% per day in the amino acid-fed ones. The former value was significantly higher than the latter one.

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The synthesis of (±)-cyclocymopol (1) is described. Brominative cyclization with 2, 4, 4, 6-tetrabromocyclohexadienone of cymopol bismethoxymethyl ether (7), which was obtained by monogeranylation of 2, 5-dibromohydroquinone bismethoxymethyl ether (5), resulted in the formation of an undesired tricyclic compound 9. In contrast, an analogous reaction of cymopol dimethyl ether (6) provided the requisite cyclocymopol dimethyl ether (4). A two-step reaction of 4 involving oxidative demethylation with eerie ammonium nitrate or silver dipicolinate and reduction with sodium hydrosulfite gave rise to (±)-cyclocymopol (1).

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(±)-cis and (±)-trans-4'-Hydroxy-γ-ionylideneacetic acids (1a and 2a) were synthesized from (±)-cis- and (±)-trans-4'-acetoxy-γ-cyclocitrals (11a and 11b), respectively, which were obtained by [2, 3]-sigmatropic rearrangement of the bromide (9a) prepared from isophorone. Racemic la was also synthesized from (±)-2, 2-dimethyl-4-THPoxy-1-cycIohexanone (14) in 12 steps.

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Silkworm antitrypsin (sw-AT) isolated from larval hemolymph was limitcdly digested by Achromobacter lysylendopeptidase, α-chymotrypsin, subtilisin BPN', subtilisin Carlsberg, papain, or Pseudomonas elastase. Each proteinase could cleave specific site(s) around the reactive site identified for the reaction of sw-AT and bovine trypsin. Among these proteinases, only subtilisin BPN' was inhibited by sw-AT, although weakly. By the cleavable amino acid sequence in sw-AT, it was suggested that whether or not these proteinases were inhibited by sw-AT did not solely depend on their substrate specificities. The susceptibility to the attack of proteinase should indicate that this region is exposed on the molecular surface. The amino acid sequence in the COOH-terminal region slightly away from the reactive site in sw-AT had homology with that in the corresponding region of the serine proteinase inhibitor (serpin) group.

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Silkworm antitrypsin (sw-AT), which was thought to belong to serpin family, changed its behavior against denaturation after chymotryptic cleavage of a single peptide bond (Tyr-Val) two amino acids away from the reactive site for trypsin (Lys-Val). This chymotrypsin-modified sw-AT became resistant to denaturation by heat, sodium dodecyl sulfate, or guanidine hydrochloride, and this characteristic was evident in its circular dichroism spectrum. The modified sw-AT was also indigestible by S. aureus V8 protease. These facts should indicate a structural change from a stressed, unstable state to a stable one accompanying the cleavage of the single peptide bond in sw-AT. The stabilizing factor was in part attributed to the interaction of a COOH-terminal fragment (5kDa) and an NH₂-terminal one (36 kDa) in modified sw-AT.

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A novel enzyme, of a Pseudomonas species, was purified by ammonium sulfate fractionation and column chromatographies on DEAE-Toyopearl 650M and Toyopearl HW-55s.
The activity recovery was 87 % at the ammonium sulfate fractionation step and 44 % at the final step of the purification, respectively. The purified enzyme was homogeneous electrophoretically and its molecular weight was 72, 000. The optimum pH and temperature were 6.5 and 55°C, respectively. The enzyme was stable up to 45 C in the pH range of 6.5 to 9.0 for 1 hr, and thermostable in the presence of 2 mM CaCl₂ up to 50°C. The isoelectric point of the enzyme was 6.5. The enzyme activity was inhibited by metal ions such as Zn²⁺, Cu²⁺, Ag⁺and Hg²⁺, and enhanced by Rb⁺, Mg²⁺, Co²⁺and Ca²⁺.
The enzyme specifically produced maltopentaose from starch in the initial stage of the reaction, finally producing maltose and maltotriose. The enzyme did not act on glucose, maltose or maltotriose, and maltohexaose was considerably resistant to the enzyme's action. In the initial stage of hydrolysis, G₂ and G₅ were formed from G₇, and thus G₃+G₅ from G₈, G₄+G₅ from G₉, G₅+G₅ from G₁₀, and G₆+G₅ from G₁₁. Through the next action, G₄ and G₅ were degraded to G₂+G₂ and G₂+G₃, respectively. The enzyme action proceeds over the branching points of amylopectin to produce large amounts of G2 and G3, and a residual amount of oligosaccharides having less than 10 glucose units in the final stage of the reaction.

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Two glycopeptides were isolated from a tryptic digest of ricin A-chain variant by gel filtration and reversed-phase HPLC. Their amino acid compositions and sequences showed that Asn-10 and Asn-236 are glycosylated. The sugar chains were liberated from these glycopeptides by hydrazynolysis, N-acetylated, and pyridy laminated. Component analysis and comparison of elution positions of the purified pyridylamino (PA-) sugar chains with those of authentic PA-sugar chains from the major ricin A-chain by reversed-phase HPLC and size fractionation HPLC suggested that both sugar chains linked to Asn-10 and Asn-236 of the ricin A-chain variant are M3FX, identical to that linked to Asn-10 of the major ricin A-chain.

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The flavoring effects of a water extract of garlic (Allium sativum L.) being added to common soups (Chinese soup and curry soup) were examined by a sensory evaluation. When a small amount (0.1 or 0.4% w/v) of the extract was added to the soups, it showed characteristic kokumi flavors (continuity, mouthfulness, and thickness), and other tests revealed that this effect was clearly recognized in the umami solution composed of 0.05 % w/v of monosodium glutamate and 0.05 % w/v of disodium inosinate.
To find the key compounds which gave rise to the effect, the water extract was chromatographed on Duolite C-25 and the adsorbed fraction showed the activity. Further chromatographic studies of the fraction showed that the key compounds were sulfur-containing components, such as alliin, (+)-S-methyl-L-cysteine sulfoxide, and γ-L-glutamyl-S-allyl-L-cysteine.

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Major anthocyanins of root peels of atsumi-kabu (red turnip, Brassica campestris L.) were isolated and identified as cyanidin-3-diglucoside-5-monoglucoside (I, rubrobrassicin), cyanidin-3, 5-diglucoside (II), and cyanidin-3-monoglucoside (III). The effects of these anthocyanins on serum cholesterol levels were examined in rats fed for 3 weeks on either a control diet based on lardcholesterol or experimental diets containing 0.03 % I or 0.045 % of a mixture of II and III (I for experiment 1, and mixture of II and III for experiment 2). Significant increases in serum high density lipoprotein (HDL)-cholesterol levels and significant decreases in the atherogenic index ((total cholesterol - HDL-cholesterol)/HDL-cholesterol) were observed in rats fed on a diet containing I (experiment 1). In experiment 1, total cholesterol - HDL-cholesterol (VLDL-+ LDL-choIesteroI) somewhat decreased in rats fed on a diet containing I. A significant decrease in atherogenic index was observed in rats fed on a diet containing the mixture of II and III (experiment 2). Besides, in experiment 2, total cholesterol and total cholesterol - HDL-cholesterol somewhat decreased in rats fed on a diet containing the mixture of II and III.

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The high yield stereoselective reduction of ketopantoic acid to D-(-)-pantoic acid with microbial cells as a catalyst is described. High activity was found in several bacteria belonging to the genus Agrobacterium. On incubation with a soil isolate, Agfobacterium sp. S-246, the yield of D-(-)-pantoic acid reached 119 rag/ml, with high molar conversion (90%) and high stereoselectivity (>98% enantiomeric excess). Ketopantoic acid reductase (EC 1.1.1.169) was suggested to be the enzyme responsible for this conversion.

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Hydrostatic pressure of 1000 to 7000 kg/cm² was applied on fresh hen egg white and yolk, carp crude actomyosin, a paste of rabbit meat, and a suspension of soy protein at 25°C for 30 min. Gels that stand under their own weight maintaining their shapes were obtained at 6000 kg/cm² for the egg white, 4000 kg/cm² for the egg yolk, 2000 kg/cm² for the carp actomyosin and the rabbit meat, and 3000 kg/cm² for the soy protein. These pressure-induced gels generally kept their original color and flavor, and were glossy and soft in comparison with heat-induced gels. According to textural measurements, the gels tended to increase in hardness and to decrease in adhesiveness with an increase in the pressure applied. However, they had large extensibility and were not fractured by a high stress.

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Molecular species of the major phospholipids, phosphatidylcholine (PC, 49 % of total phospholipids), phosphatidylethanolamine (PE, 27%), and phosphatidylinositol (PI, 11%), of Lilium longiflomm pollen grains were analyzed. Fatty acid compositions (sn-l/sn-2) of major molecular species of PC, PE, and PI were 18:3/18:3, 18:2/18:3 (and/or 18:3/18:2), 18:2/18:2, 16:0/18:3, and 16:0/18:2. Molecular species compositions were quite similar among PC, PE and PI. Mature pollen grains contained more unsaturated molecular species than immature pollen grains.

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Using 12 chimeric cyclomaltodextrin glucanotransferases (CGTases) constructed from two genes, the CGTase gene from the alkalophilic Bacillus sp. strain No. 38-2 (CGTase 38-2 gene) and the CGTase gene from the alkalophilic Bacillus sp. strain No. 17-1 (CGTase 17-1 gene), we compared the effect of those chimeric enzymes on cyclodextrin (CD) production, especially on the composition of the CDs produced. It was found that the N-terminal and the C-terminal segments were important for CD production. Chimeric enzymes that contained the N-terminal and the C-terminal segments derived from CGTase 38-2 produced large amounts of CD, and especially a higher proportion of alpha-CD than those of other chimeric enzymes.

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The cDNA for rat monoamine oxidase A (MAO-A) mRNA was isolated from a liver cDNA library in λ gtll as the cDNA species cross-hybridizing with rat monoamine oxidase B (MAO-B) cDNA. The primary structure of the protein, deduced from the nucleotide sequence, consisted of 526 amino acid residues and its molecular mass was calculated to be 59.6 kD. The amino acid sequence shows about 70% identity with that of rat MAO-B. Northern blot analysis showed that MAO-A mRNA was expressed in various rat tissues and the highest expression was observed in heart. The MAO-B mRNA was quite different from MAO-A mRNA in the tissue-specific expression and liver had the highest level of the mRNA.

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