The photolysis mechanism of riboflavin (RF) in milk serum was studied. When milk serum was light-illuminated, the decomposition of RF in the serum was accelerated. Superoxide anion (O₂^-) and hydrogen peroxide (H₂O₂) were found to form during the illumination, while superoxide dismutase (SOD) activity could not be detected in the milk serum. The decomposition of RF was significantly inhibited by the addition of tryptophan or mannitol which are scavengers of the hydroxyl radical. Conversely, addition of Fe³⁺ or lactoferrin promoted the decomposition.
These results strongly suggest the direct participation of the hydroxyl radical in the RF decomposition in milk serum during light-illumination. It was also suggested that the hydroxyl radical was formed via the iron catalyzed Haver-Weiss reaction in which iron reacts with O₂^- and H₂O₂, although it is still unknown how O₂^- and H₂O₂ were generated by illumination.

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4-Hydroxy-3, 7-dimethyl-2, 6-octadienal (5-Hydroxycitral) (2) was prepared from 3, 7-dimethyl-2, 6-octatrienal (citral) (1) via bromoaldehyde (4) and acetoxyaldehyde (6). 3, 7-Dimethyl-2, 4, 6-octadienal (7) was also obtained as a byproduct. 4-Hydroxy-3, 7-dimethyl-2, 6-octadienal (2) showed similar growth inhibition activity to that of 1 against Sarcoma180.

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The relationships among the spinnability, the rheological properties, the spun fiber strength, and the inhibition of lysinoalanine (LAL) formation with the addition of reducing agents were studied to get safe, edible, fibrous soy protein, having excellent spun fiber strength, when a dope of 20% protein concentration was used as a normal dope. It was found that cysteine and 2-mercaptoethanol were effective in reducing LAL formation and the dopes prepared with the addition of these agents showed almost the same spun fiber strength as that of the normal dope prepared without agents. Especially, cysteine was the most effective agent for inhibiting LAL formation to get fibrous protein for meat analogues. The most suitable concentration for inhibiting LAL formation was 2% cysteine in the total protein. The dopes with the addition of 2-mercaptoethanol and Na₂SO₃ had lower viscoelastic values and their frequency dependence of G' was higher than that of the normal dope. However, the dopes with the addition of other reducing agents (NaHSO₃, glycine, reduced glutathione) had higher viscoelastic values and lower frequency dependence of G'. The viscoelastic values of the dopes with the addition of 2-mercaptoethanol, Na₂SO₃, and that of the normal dope were decreased with the lapse of time, but the dopes prepared by the addition of other agents had constant viscoelastic values.

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GA₁, GA₃, GA₅, GA₁₉, GA₂₀ and GA₂₃ were identified by GC-MS in the acidic ethyl acetate-soluble fraction from the seeds of sweet potato (Ipomoea batatas Lam.). GA₁₉ and GA₂₃ were major Gas in the mature seeds, their contents being about 200 and 160 μg/kg fresh weight, respectively, while those of GA₁₉ and GA₂₃ in immature seeds were below 100 μg/kg fr. wt. The occurrence of glycosyl conjugates of GA₃, GA₅, GA₈, GA₁₇, GA₁₉, GA₂₀, GA₂₃ and GA₄₄ in the butanol fraction from mature seeds was shown by GC/MS analysis after enzymatic hydrolysis.
Besides the endogenous GAs in sweet potato, those in immature seeds of several other Convolvulaceae plants were investigated. The species of endogenous Gas were discussed in terms of chemotaxonomy.

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The hydrolysis of konjac glucomannan by a purified extracellular mannanase from Streptomyces sp. produced four kinds of oligosaccharides containing both glucose and mannose residues. These glucomanno-oligosaccharides were identified as O-β-D-glucopyranosyl-(1→4)-Dmannopyranose (epicellobiose, G₁M₁-I), 0-β-D-glucopyranosyl-(1→4)-O-β-D-mannopyranosyl- (1→4)-D-mannopyranose (G₂M₁-I), O-β-glucopyranosyl-(1 →4)-O-β-D-glucopyranosyl-(1→4)-D-mannopyranose (G₂M₁-I) and O-β-D-glucopyranosyl-(1 →4)-O-β-D-glucopyranosyl-(1→4)-O-β-D-mannopyranosyl-(1→4)-D-mannopyranose (G₂M₂-I). On the basis of the structure of the above oligosaccharides, the mode of action of the mannanase on the glucomannan is discussed.

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The apoenzyme of glucose oxidase (EC 1.1.3.4) from Aspergillus niger was modified by diethylpyrocarbonate (DEPC). A second-order rate constant of inactivation with respect to the regaining of activity when reconstituted with FAD was 33.7M^-1s^-1 at pH 6.2 and 25°C. This inactivation was reversed up to 60% by the addition of 0.25 M hydroxylamine. It was suggested that histidyl residues having pK_a = 8.2 were responsible for the reconstitution reaction of holo-oxidase from its pH-dependence of inactivation. In addition to these histidyl residues, two SH-groups were particitated in the DEPC modification, and these residues seemed likely to interact with each other. From the studies on the enzyme kinetics, CD spectra, and stoichiometry on the modification of histidyl residues, all data suggested that inactivation of apoenzyme with DEPC was due primarily to the modification of two histidyl residues essential for the binding of FAD and two cysteines near these residues. The present investigation suggested that there were some other histidyl residues necessary for maintaining the proper conformation of native glucose oxidase.

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A method for determining the tryptophan content of feed and feedstuffs was established. This method involved three steps: alkaline hydrolysis, pretreatment of the hydrolysate for chromatography, and measurement of tryptophan by ion exchange liquid chromatography. With this method, the recovery of tryptophan in egg-white lysozyme, which is a pure protein with six tryptophan residues, was 97%. It was shown that co-existing nutrients, such as carbohydrate, fiber, and free or combined ash, did not affect the recovery of tryptophan in lysozyme, but that the recovery of tryptophan was reduced by the presence of fat. Therefore, defatting of feed and feedstuffs is necessary to obtain accurate values for tryptophan analysis by this method. The tryptophan contents of some proteins, feedstuffs, and feeds were determined under the optimum conditions established in this study.

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Dried tempeh is known to be remarkably stable to lipid oxidation. An isoflavone has been isolated and is considered to be one of the antioxidants in tempeh. However, the true origin of the antioxidative activity of tempeh is still obscure. In this paper, isoflavones and their glucosides in tempeh were analyzed by HPLC, and the liberation of isoflavones from glucosides occurred during fermentation was made clear. The main isoflavones responsible for the antioxidative activity in tempeh were deduced to be daidzein and genistein.

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Nitrate and nitrite were successfully extracted from deproteinized chicken egg with aqueous solution, and analyzed by gasliquid chromatography with an electron capture detector without further cleaning. The distribution of these anions in 50 egg samples was the logarithmic normal distribution in each case, that is, N (2.796 (=0.063ppm), 0.295) and p {0.052ppm ?? μ ?? 0.076ppm}=0.95 for nitrate-N, and N (2.470 (=0.030ppm), 0.227) and p {0.026ppm ?? μ ?? 0.034ppm}=0.95 for nitrite-N. When the chickens were fed with a commercial diet containing elevated levels (1, 000 or 5, 000ppm) of nitrate- or nitrite-N, the concentration of these anions in their eggs markedly increased and proceeded to the steady state within 2 or 3 days, where the level was proportional to that of anions added to the diet. After withdrawing the excess of anions from the diet, the concentrations of anions in the eggs decreased exponentially, where the rate constants for nitrate and nitrite were about 0.6 day^-1 and 1.0 day^-1, respectively. In the series of experiments, it was assumed that the reactions NO₃^-→NO₂^- and NO₂^-NO₃^- proceed simultaneously in the body of chickens.

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Flow properties of aqueous deacetylated xanthan solutions could be approximated to pseudoplastic behavior at concentrations below 0.1% but to plastic behavior above 0.3%. The flow indices in the power law for the deacetylated xanthan were somewhat different at various concentrations. The apparent viscosity of deacetylated xanthan decreased with increasing temperature at relatively low concentrations from 0.1 to 0.5%, however, it increased with increasing temperature, showed a maximum value at 40°C and decreased gradually at 1.0%. Compared with native xanthan, deacetylated material showed higher dynamic viscoelasticity at high concentrations. The dynamic viscoelasticity of deacetylated xanthan decreased with increasing temperature at various concentrations. The dynamic viscoelasticity of deacetylated xanthan was decreased by addition of urea (4.0M).
This suggests that acetate residues, which are attached to the inner mannose residues of the side chains, contribute to the intramolecular association, and that the side chains of xanthan become more flexible after deacetylation.

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Non-Newtonian behavior and dynamic viscoelasticity of a series of aqueous mixed solutions of xanthan and locust bean gum were measured using a rheogoniometer, and the rheological properties were analysed. A gelation occurred in the mixture at the concentration of 0.2% total gums at room temperature. The flow curves of the mixture solutions showed a yield value and approximated to plastic behavior at 50°C. The maximum dynamic modulus was obtained when the mixing ratio of xanthan to locust bean gum was 1:2, while comparable high moduli were also obtained in the mixing ratio of 1:3 or 1:4. A mixture of deacetylated xanthan and locust bean gum showed the highest dynamic modulus, about two times that of the mixture of native or Na-form xanthan. The dynamic modulus of the mixtures decreased rapidly with increasing temperature. In contrast, the dynamic viscosity was scarcely changed during increasing temperature in the mixing ratio of 2:1. The dynamic modulus was decreased by addition of urea (4.0M), NaCl (0.1%) and MgCl₂. We concluded that the intermolecular interaction between xanthan and locust bean gum might occur between the side chains of the former and backbone of the latter, as in a lock-and-key effect.

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In order to elucidate the nature of malodor from piggery wastes, volatile compounds in fresh faeces, fresh urine, rotten urine, and rotten mixtures of faeces and urine were isolated by freeze vacuum distillation and continuous extraction and identified by gas chromatography-mass spectrometry. Many alcohols were detected not in fresh urine, but in faeces. Various fatty acids were determined at high concentrations in all samples, but their abundance was different in faeces and urine. Large amounts of phenols came from urine. Aromatic carboxylic acids were detected only in urine and decreased rapidly during digestion. Indole and 3-methylindole which were present only in faeces showed a reverse change of concentration during digestion.

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Reconstitution of highly purified P700-chlorophyll a protein complexes into the chloroplast lipid vesicles and their kinetic properties have been studied. All four major chloroplast lipids, monogalactosyldiacyl-, digalactosyldiacyl-, sulfoquinovosyldiacyl-, and phosphatidyl-glycerol, which were purified from spinach leaves, were found to form liposomes in the presence of 20% (w/w) phosphatidylcholine and function as a barrier against small molecules such as ascorbate and potassium ferricyanide. Plastocyanin, added to the preformed reaction center-liposomes, reduced up to 90% of photooxidized P700 in the P700-chlorophyll a protein complexes, which suggests that the portion of P700-chlorophyll a protein complexes which accomodate the transfer of electrons from plastocyanin is exposed predominantly on the exterior of the vesicles. The effects of cations on the electron transfer from plastocyanin to photooxidized P700 in the reconstituted system were similar to that in the solution system, which suggests the importance of local charges proximal to P700 in the P700-chlorophyll a protein complexes and a minor role of lipid membrane on the effects of cations in the reaction.

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Attempts to solubilize active ubiquinol : cytochrome c reductase, cytochrome b-c₁ complex, from the submitochondrial particles from sweet potato root tissue ended in failure because all detergents tested caused inactivation of this enzyme complex. Consequently, the complex was isolated with the content of cytochrome b as the marker for purification after solubilization with deoxycholate though it was inactive. Deoxycholate had no effect on two α-bands at 555 and 558nm but caused a blue shift of an α-band at 563nm in the reduced-minus-oxidized difference spectrum of the submitochondrial particles at low temperature. The purified complex exhibited the same difference spectra at low and room temperatures as the submitochondrial particles in the presence of deoxycholate, which suggests that the complex has three (at least two) cytochrome b components with different spectroscopic properties and that the apparent molar ratio of cytochrome b to c₁ is 1.5. The purified complex consisted of eight subunits: I, 51kDa ; II, 49kDa ; III, 33kDa ; IV, 32kDa ; V, 27kDa ; VI, 17kDa ; and VII and VIII, 10kDa. Subunits III and IV were cytochrome c₁ and b, respectively.

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A type II restriction endonuclease, designated as AliAJI, was purified from cells of Acetobacter liquefaciens AJ 2881 by combined column chromatography on heparin-Sepharose CL-6B, DEAE-Sepharose CL-6B and blue Sepharose CL-6B. The purified enzyme was homogeneous on polyacrylamide gel disc electrophoresis, and the enzyme preparation was free from other nuclease activities, as judged by constancy of lambda DNA-digest electrophoretic patterns after prolonged incubation for 24hr. The enzyme was optimally active at 37°C at pH7.5, required neither sodium chloride nor ammonium sulfate, both of which rather inhibited enzyme activity at high concentration (100 and 75mM, respectively), and cleaved lambda, φX174 RF, SV40, pBR322, M13 mp7 RF and Ad2 DNAs at 18, 1, 2, 1, 1 and 25 or more sites, respectively. The recognition sequence of the enzyme on DNA molecules was determined to be 5'-C-T-G-C-A-G-3', and the enzyme was found to cut between A and G in the sequence, being an isoschizomer of the endonuclease of Providencia stuartii 164 (PstI).

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A prolidase with a molecular weight of 43, 000 was purified to homogeneity from a cell-free extract of Streptococcus cremoris H61. The optimum pH of the enzyme was in the range of 6.5 to 7.5. The hydrolyzing activity was specific for dipeptides of the X-Pro type. Kinetic constants for 4 dipeptides (Leu-Pro, Phe-Pro, Val-Pro and Ala-Pro) were estimated. Km values were not very different for these substrates, but V_max values were quite different (Leu-Pro> Phe-Pro, Val-Pro> Ala-Pro). The enzyme was activated by cobalt ion and inactivated by metal-chelating agents or with 2-mercaptoethanol.

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The production of neoviridogrisein II, a peptidolactone antibiotic, was suppressed by glucose in Streptomyces griseoviridus G-89. Pyruvic acid accumulated in the glucose-supplemented culture. The glucose effect was correlated with inhibition by pyruvic acid but not with low pH of the culture broth.

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Commercial Philippine fish sauce (Patis) was steam-distilled and the distillate was fractionated into four fractions, neutral, basic, acidic and phenolic and each fraction was analyzed using gas chromatography and gas chromatography-mass spectrometry.
As a result of this study, a total of 66 compounds were identified in Patis, 14 of which were only a tentative identification. Out of these 66 identified compounds, 40 identified compounds have not been reported in previous studies on fish sauces. These identified compounds include 19 acids, 14 alcohols, 12 nitrogen containing compounds, 5 esters, 3 sulfur containing compounds, 1 phenol, 3 carbonyls, 7 hydrocarbons and 2 others. In the acidic fraction, 5 acids were considered major constituents which accounted for about 98% of the total acids. n-Butanoic acid was found to be the most abundant accounting for about 50% of the total acids.

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β-Galactosidases (EC 3.2.1.23) from Bacillus circulans were purified and separated into two different enzyme forms, using Sephadex G-150, ion-exchange, polybuffer chromatography, and preparative polyacrylamide gel electrophoresis. The molecular weights estimated for these two enzymes were 2.4×10⁵ (β-galactosidase-1) and 1.6×10⁵(β-galactosidase-2). They showed similar isoelectric points of about 4.5 and the same optimum pH of 6.0, whereas they were considerably different in Km values, substrate specificity, and particularly oligosaccharide-producing activity. β-Galactosidase-2 produced many galacto-oligosaccharides, including di-, tri-, tetra-, and pentasaccharides, during hydrolysis of 4.56% lactose. When 60% of the lactose was converted, the total amount of oligosaccharide production reached a maximum at which about 41% of the products formed were oligosaccharides. β-Galactosidase-1 produced only 6% at its maximum.

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Ungerminated spores of the sweet potato strain of Ceratocystis fimbriata are highly sensitive to spore-agglutinating factor (SA factor) from sweet potato roots and are agglutinated by the factor at low concentrations. However, they become less sensitive to the factor when they germinate. The substances (SAI substances) that inhibited spore agglutination by SA factor were released by sonication from the surface of germinated spores of the sweet potato strain and isolated. The substances seemed to re-bind efficiently onto the surface of the sonicated spores at pH 6.5 in the presence of Ca²⁺ (10mM) and this made them less sensitive to SA factor. The substances were assumed to be proteins from the inactivation by heat and trypsin treatments. The substances diminished, to a similar degree, the sensitivity to SA factor of germinated spores of all seven strains of C. fimbriata ; the sweet potato, coffee, prune, cacao, oak, taro, and almond strains. The substances stimulated the growth of sweet potato, coffee, cacao, and taro strains in liquid media, while the growth of prune, oak, and almond strains were inhibited by the substances. These results are discussed in relation to differential agglutination of germinated spores of various strains by SA factor and to host-parasite specificity.

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Seven aryl methyl phosphorochloridothionates were prepared and examined for reactivity as two-step phosphorylating reagents to synthesize oxazaphospholidine sulfide. The 2, 6-dichloro-4-methylphenyl and p-nitrophenyl derivatives (CMPC and MNPC) were selected and resolved into optically active enantiomers. Their absolute configurations were determined. Even in the presence of an alcohol, an amine first attacked the phosphorus displacing the chloride ion. The amide that was produced reacted with an alkoxide to displace the aryloxide ion. Both the substitutions underwent inversion of the configuration.

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To reveal the mechanism of reducing sugar-induced polymerization of proteins, monomeric lysozymes were isolated at various stages of storage from whole lysozyme (WL) being kept with glucose at 75% relative humidity and 50°C for up to 30 days, and their chemical properties were investigated and compared with the corresponding WL. The impairment of Lys, Arg, and Trp residues was observed in all the isolated monomeric lysozymes (IM) as well as in the WL.
When the IM were stored for another 10 days without glucose, they polymerized and had an additional impairment of Arg and Lys but not Trp residues. All IM exhibited almost the same polymerization rate, but the sum of additional losses of Lys and Arg residues varied. The IM was also found to cross-link untreated lysozymes even in the absence of glucose.
On basis of the results obtained hitherto, it is suggested that the glucose-induced polymerization of lysozymes proceeds through the following paths. At the first step, some bifunctional agents (BF), probably α-dicarbonyl compounds, generated from the reaction between ε-amino groups of lysine residues and glucose, attach to Arg, Lys, and Trp residues through one of their two functional sites. At the second step, some of those proteins with BF attached polymerize by binding of the other unoccupied functional site with the remaining Lys and Arg (not Trp) residues of the other protein molecules. The other of the proteins with BF attached polymerize through the combination between the other unoccupied functional sites themselves with no loss of amino acid residues.

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Mutants with low pyruvate dehydrogenase (PD) activities were derived from a pyruvate kinase-deficient lysine-producing mutant of Brevibacterium flavum, No. 22. They were selected as prototrophic revertants of the acetate auxotrophs of strain No. 22. Among them strain KD-11 produced 55g/liter of lysine as its HCl salt when cultured for 72hr in a medium containing 100g/liter of glucose, soybean-meal hydrolysate and methionine. The lysine yield of strain KD-11 was the highest ever reported (55%). The mutant required a higher concentration of methionine for maximum production and gave a smaller amount of cell mass in cultivation than its parent. PD activity of strain No. 22 was stimulated by cysteine, stabilized by glycerol, and gave apparent Kms of 89, 22, 380, 83 μM for pyruvate, coenzyme A, 3-acetylpyridine adenine dinucleotide, and NAD, respectively, under standard conditions. The apparent Km for NAD of PD from strain KD-11 was 10-times higher than that from No. 22. When the concentration of NAD was low, the cell extracts of strain KD-11 showed low PD activity. The specific activity of phosphoenolpyruvate carboxylase of strain KD-11 was slightly higher than that of strain No. 22, while the inhibition by aspartate of the former enzyme was weaker than that of the latter.

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The finding that most strains of microbes produce a growth stimulating substance for microorganisms was demonstrated and confirmed with the culture broth of Escherichia coli grown on a glucose-mineral medium. Addition of culture broth of E. coli to the culture media of the others markedly reduced the lag phase in microbial growth but not growth rate in the subsequent exponential phase nor the total cell yield in the stationary phase. The growth stimulation causing reduction of the lag phase was dependent on the amount of culture broth added. Occurrence of cell growth was essential for the excretion of the growth stimulating substance by E. coli. Under identical inoculum size, even with a heavy inoculum, a further reduction of the lag phase was observed by the addition of culture broth of E. coli. The substance was only effective at the initial growth phase but inert when the substance was added to a growing culture at the exponential phase. Finally, the substance was identified as pyrroloquinoline quinone, a newly established coenzyme, through chromatographic, spectroscopic and enzymatic criteria.

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Pievious work with MAPI, a serine protease inhibitor, has shown that inactivation of membrane bound protease by MAPI resulted in inhibition of normal sporulation of Bacillus subtilis IFO 3027 [Shimizu et al., Agric. Biol Chem., 48, 365 (1984)]. In the cells cultured with MAPI, the cellular amount of IP-I, a cytoplasmic serine protease which is sensitive to EDTA was lower than the control cells. An endogenous proteinaceous inhibitor having specific inhibitory activity against IP-I was produced during the sporulation and its amount in the MAPI-treated cells was higher than that of control cells. The proteinaceous inhibitor was inactivated only by membrane bound protease. Consequently, IP-I was activated through degradation of proteinaceous inhibitor by membrane bound protease. It seems probable that the proteinaceous inhibitor and membrane bound protease are involved in the regulation of a protease system in sporulating cells of B. subtilis.

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A number of 1-citronellyl-5-substituted imidazoles were synthesized and bioassayed on the silkworm, Bombyx mori, in order to assess their anti-juvenile hormone activity. Most of the 1-citronellyl-5-substituted imidazoles induced precocious metamorphosis in the 3rd and 4th instar larvae of B. mori by topical application. The percentage of precocious metamorphosis correlated well with the dosage. Among the compounds tested, 1-citronellyl-5-(2-chlorophenyl)imidazole (8) and the 2-methylphenyl analog 10 showed the highest activity. When compounds 8 and 10 were applied to the 4th instar larvae at 10μg/larva, precocious pupation was induced in 100% without any lethal effects.

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Two simple methods, the Tenax GC method and the active carbon method, have been developed to analyze the headspace volatiles of tobacco. The headspace volatiles swept by helium from cut tobacco were collected by either Tenax GC or active carbon and were analyzed by gas chromatography after desorption by heating the Tenax GC or by extracting the active carbon with dichloromethane. The gas chromatograms of the headspace volatiles of flue-cured tobacco obtained by these two methods differed. Both methods showed good reproducibility and were applied to the analysis of the headspace volatiles of American and Japanese flue-cured tobacco samples. By principal component analysis, three or four principal components were. extracted from the 15 selected peaks of the headspace volatiles of these samples that had been obtained from both the Tenax GC and the active carbon methods.

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The sex pheromone of the Rice stem borer, Chilo sappressalis WALKER (Lepidptera: Pyralidae), (Z)-11-Hexadecenal, was biosynthesized by feeding experiments with possible deuterized precursors and tested by a GC-SIM analysis of the pheromone component. The pathway commenced by hexadecanoic acid being reduced to the hexadecanal, from which (Z)-11-hexadecenal was biosynthesized by the introduction of a double bond.

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In order to develop a new method for determination of the G+C content of a DNA, preparations from 26 bacterial strains and salmon sperm were digested to form 5'-deoxyribonucleotide-monophosphates (dNMP) with nuclease P1 and subjected to high performance liquid chromatography (HPLC). Chromatograms indicated excellent separation of the components, and the data analysis suggested sufficient reproducibility and reasonable A/T and G/C ratios over a wide range (39 to 72mol%) of G+C values.

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