The effects of ceramics radiation on nitrosation of dimethylamine with nitrite in citrate buffer of pH 3.4 was studied using a ceramics plate and a ceramics heater. The rate constant of nitrosodimethylamine (NDMA) production under the irradiation conditions decreased by 81% from the non-irradiated reaction, and that of nitrite degradation increased 1.5-fold. The activation energy for NDMA production and nitrite degradation after 4h of irradiation decreased by 53 and 73% of the non-irradiated reactions, respectively. It was estimated that the hydration effects of the ceramics radiation were concerned in the repression of NDMA production and the acceleration of nitrite degradation.

View full abstract

Feeding sesamin and α-tocopherol in combination, both at the 0.5% dietary level, to Sprague-Dawley rats for 3 weeks resulted in a trend toward decreasing the proportion of 20:4n-6 and 22:5n-6 and increasing that of 18:2n-6 in phosphatidylcholine from various tissues, suggesting interference with the metabolism of linoleic acid. This dietary manipulation significantly reduced the production of leukotriene C₄ in the lung, the splenic production of leukotriene B₄, and reduction of the plasma histamine level. Simultaneous administration of sesamin and α-tocopherol signiticantly increased the production of IgA, IgG, and IgM by mesenteric lymph node lymphocytes, while the IgE level tended to be reduced. These effects were not necessarily apparent by feeding these compounds separately. Thus, sesamin and α-tocopherol in combination would be effective for regulating the eicosanoid production and modifying the immune function.

View full abstract

Amino acid-carboxymethyl starch granule (AA-CMS) conjugates were prepared by using water-soluble carbodiimide (1-ethyl-3-(3-dimethylaminopropyl) carbodiimide) to improve the functions of starch. Slightly modified potato CMS was dispersed in a 5% water-soluble carbodiimide solution. An amino acid (Glu, Cys, Lys, Gly, Leu, or Phe) solution was added, and the reaction mixture was incubated at 24°C for 5h, resulting in the formation of an acid-amide bond between CMS and the amino acid. Each AA-CMS conjugate was recovered after thoroughly washing with distilled water and air-drying. The functional changes of the starch were investigated by microscopic observation, differential scanning calorimetry (DSC), solubility, and digestibility with α-amylase or β-amylase. The swelling and solubility of the AA-CMS conjugates were much lower than those of CMS. Data from DSC shows that the conjugates gelatinized at a higher temperature than CMS and were difficult to retrograde, especially the conjugates with hydrophobic amino acids. The digestibility of the conjugates with α-amylase or β-amylase was markedly decreased as compared with that of CMS and native starch.

View full abstract

A cowpea glubulin isolate was treated with protein kinase, and the functional properties of the reaction product were compared with those of a native protein isolate in the range pH 3-8. The phosphorylated proteins significantly exhibited (p ≤ 0.05) increased solubility in the range pH 4-6, but the solubility at pH 3, 7, and 8 was significantly (p ≤ 0.05) decreased when compared to that of the native proteins. The emulsifying activity index was significantly (p &ie; 0.05) decreased, but the emulsion stability of the proteins was generally increased (p ≤ 0.05) over the pH range investigated due to phosphorylation. The foaming capacity and foam stability were each signinificantly (p ≤ 0.05) increased in the range pH 4-6 and at pH 4 and 5, respectively, as a result of phosphorylation.

View full abstract

Arthrobacter sp. Q36 produces a novel enzyme, maltooligosyl trehalose synthase, which catalyzes the conversion of maltooligosaccharide into the non-reducing saccharide, maltooligosyl trehalose (α-maltooligosyl α-D-glucoside) by intramolecular transglycosylation. The enzyme was purified from a cell-free extract to an electrophoretically homogeneous state by successive column chromatography on Sepabeads FP-DA13, DEAE-Sephadex A-50, Ultrogel AcA44, and Butyl-Toyopearl 650M. The enzyme was specific for maltooligosaccharides except maltose, and catalyzed the conversion to form maltooligosyl trehalose. The K_m of the enzyme for maltotetraose, maltopentaose, maltohexaose, and maltoheptaose were 22.9 mM, 8.7 mM, 1.4 mM, and 0.9 mM, respectively. The enzyme had a molecular mass of 81, 000 by SDS-polyacrylamide gel electrophoresis and a pI of 4.1 by gel isoelectrofocusing. The N-terminal and C-terminal amino acids of the enzyme were methionine and serine, respectively. The enzyme showed the highest activity at pH 7.0 and 40°C, and was stable from pH 6.0 to 9.5 and up to 40°C. The enzyme activity was inhibited by Hg²⁺ and Cu²⁺.

View full abstract

A novel enzyme, maltooligosyl trehalose trehalohydrolase from Arthrobacter sp. Q36 was purified from a cell-free extract to an electrophoretically pure state by successive column chromatography on Sepabeads FP-DA13, Butyl-Toyopearl 650M, DEAE-Toyopearl 650S, and Toyopearl HW-55S. The enzyme specifically catalyzed the hydrolysis of the α-1, 4-glucosidic linkage that bound the maltooligosyl and trehalose moieties of maltooligosyl trehalose. The K_m of the enzyme for maltosyl trehalose, maltotriosyl trehalose, maltotetraosyl trehalose, and maltopentaosyl trehalose was 5.5 mM, 4.6 mM, 7.0 mM, and 4.2 mM, respectively. The enzyme had a molecular mass of 62, 000 by SDS-polyacrylamide gel electrophoresis and a pI of 4.1 by gel isoelectrofocusing. The N-terminal amino acid of the enzyme was threonine. The enzyme showed the highest activity at pH 6.5 and 45°C, and was stable from pH 5.0 to 10.0 and up to 45°C. The activity was inhibited by Hg²⁺, Cu²⁺, Fe²⁺, and Zn²⁺.

View full abstract

Uptake of cesium, potassium, and rubidium by Rhodococcus erythropolis CS98 and Rhodococcus sp. strain CS402 followed Michaelis-Menten saturation kinetics. The K_m's for uptake of these monovalent cations by R. erythropolis CS98 and Rhodococcus sp. strain CS402 were 136 and 436 μM for Cs⁺, 65 and 101μM for K⁺, and 102 and 113μM for Rb⁺, respectively. These values were significantly lower than those of Rhodobacter capsulatus and the Kup system in Escherichia coli. Potassium was a competitive inhibitor of cesium uptake by these strains, suggesting that cesium was accumulated by the potassium transport system. Although an uncoupler, FCCP, inhibited the cesium transport system, this system was not repressed by high concentrations of potassium in both Rhodococcus strains. However, the specificity in both Rhodococcus strains was different from the Trk system. These results suggest that the potassium transport system which can transport cesium in both Rhodococcus strains may be novel.

View full abstract

A β-1, 3-glucanase secreted by Stachybotrys elegans, when grown on minimal synthetic medium containing Rhizoctonia solani cell wall fragments, was purified to homogeneity. The purification method involved ammonium sulfate precipitation and ion-exchange and size-exclusion chromatographies. The molecular mass of the enzyme was estimated under denaturing conditions to be about 94 kDa. The enzyme had an optimum pH of 5.0 and was most active between 40 and 50°C. Except for Mn²⁺, the enzyme activity was not sensitive to the metal ions tested and K_m of 0.18mg/ml was estimated for laminarin as a substrate. Cell wall lytic activity of purified β-1, 3-glucanase was tested on actively growing R. solani hyphae. β-1, 3-Glucanase induced morphological changes such as hyphal tip swelling, bursting, leakage of cytoplasm, and formation of numerous septae

View full abstract

An unusual amino acid, (2S, 3R, 4R, 6E)-2-acetylamino-3-hydroxy-4-methyl-6-octenoic acid (2a) and its stereoisomer (2b), were synthesized by the aldol condensation of (2R, 4E)-2-methyl-4-hexenal (5) with tert-butyl isocyanoacetate (6) as the key reaction via trans-oxazoline derivative 7, in which two continuous chiral centers were newly formed. The oxazoline derivative was efficiently hydrolyzed to afford separable N-formyl-β-hydroxy amino acid esters 8a and 8b in a 1:1 ratio. Each diastereomer was transformed into target N-acetyl amino acids 2a and 2b via corresponding amino acids 1a and 1b.

View full abstract

Glycine-rich protein (GRP) was extracted with hot water from cell walls of the aleurone layer of soybean seeds and solubilized by pectinase treatment. GRP was purified by Sephadex G-100 gel chromatography, anion exchange HPLC, and reverse-phase HPLC. Two GRP fractions that had almost the same amino acid composition were found by gel chromatography. The high-molecular-mass GRP seems to be an associated form of the low-molecular-mass GRP (30-kDa). Thirty-kDa GRP was separated into a major GRP-I and a minor GRP-II by anion exchange HPLC. The major amino acids of GRP-I purified by reverse-phase HPLC were glycine (68%) and serine (12%). GRP-I contained a small proportion of sugar, approxlmately 9% (w/w), and mannose, arabinose, glucose, xylose, and galactose were included in the sugar moiety. The N-terminal amino acid sequence of GRP-I was a novel polyglycine structure including at least 20 glycine-repeated sequence. The GRP-I might be a novel type of extracellular matrix protein specific to the aleurone layer.

View full abstract

A new analysis method for protein phosphatase type 2A inhibitors was established that uses the firefly bioluminescence system for detection. Thus, firefly luciferin phosphate was used as a substrate, and the liberated free luciferin was determined from the amount of light emitted from the immobilized luciferase. This method was successfully used to determine the activities of known inhibitors, i.e., okadaic acid, calyculin A, microcystin-LR and tautomycin using less than 10 pmol of a sample.

View full abstract

The keratinase produced by Bacillus licheniformis PWD-1 was induced by feather powder. Maximal enzyme production could be achieved by culturing in a medium containing 1% hammer-milled feather powder (100 mesh) at 45°C for 30h. Maximal growth of PWD-1 was achieved at 50°C, and maximal enzyme induction was at 45°C. The molecular mass and isoelectric point of this enzyme were 31.4 kDa and 8.5, respectively. This enzyme was stable from pH 5 to 12. The optimal reaction pHs for feather powder and casein were 8.5 and 10.5 to 11.5, respectively. The optimal reaction temperature was 50°C to 55°C. The relative activity of this enzyme toward casein, feather powder, keratin, elastin, and collagen was 1OO:52:41:18:7, and 100:56:32:3 for Suc-AAPL-pNA, Suc-AAPF-pNA, Suc-AAPM-pNA, and Suc-AAVA-pNA (Suc, succinyl ; pNA, p-nitrophenylanilide).

View full abstract

Two new flavone glucosides that are considered to be useful chemotaxonomic markers were isolated from the leaves of Pyrus serotina cv. Nijisseiki. Spectral and chemical data enabled their structures to be established as 7, 4'-dihydroxy-5, 3'-dimethoxyflavone 7-O-β-D-glucoside and 7, 4'-dihydroxy-5, 3'-dimethoxy-flavone 4'-O-β-D-glucoside.

View full abstract

Syntheses of two carbonyl derivatives of hydantocidin 1, a potent, naturally occurring herbicide, and their herbicidal activity are described. Spiroimidazolidinone 2, the descarbonyl compound at C9, was prepared by employing reductive demethylsulfurization with tri-n-butyltin hydride as the key step. Another derivative, spiroimidazolinone 10, was obtained from α-azidoamide 8 and benzyl isocyanate via the aza-Wittig reaction. 2 had lost almost all herbicidal activity, whereas 10 retained herbicidal activity against such dicotyledonous weeds as ragweed and cocklebur, but lost activity against monocotyledonous weeds. These results imply the possibility that proper modification of the carbonyl group at C7 of the parent compound would afford hydantocidin analogues possessing crop selectivity.

View full abstract

In Aspergillus oryzae wild-type strains, the expression of the agdA gene encoding α-glucosidase (AGL) is induced by maltose at the transcriptional level in a similar manner to the amyB gene encoding Takaamylase A (TAA) and the glaA gene encoding glucoamylase (GLA). In A. oryzae transformants containing multiple copies of the agdA gene, a high-level of AGL activity was observed. This was accompanied by a significant reduction in TAA and GLA activities. Moreover, transformants with the highest AGL activity showed the lowest degree of TAA and GLA activities. Northern blot analyses showed that the transcriptional levels of amyB and glaA in the AGL-overproducing transformant were drastically reduced when large amounts of agdA mRNA were detected in maltose-grown mycelia. In addition, the glucose concentration of the maltose-containing medium that was used to grow the AGL-overproducing transformant for RNA extraction was higher than that of the control transformant. These results suggest that the reduced expression of the amyB and glaA genes in the AGL-overproducing transformant was due to either titration of a common regulatory protein(s) involved in maltose induction or carbon catabolite repression.

View full abstract

The effects of freezing on the proteolysis of beef during storage at 4°C after being thawed was investigated. A sarcoplasmic 32-kDa protein in frozen as well as unfrozen beef decreased rapidly during storage at 4°C, and a more than 100-kDa protein appeared in both beef samples. And the increment of peptides in the frozen beef during the storage at 4°C was larger than that in the unfrozen beef, suggesting that the proteolysis was faster during the storage of the former than the latter. However, its increment in the frozen beef for 10 weeks during the storage at 4°C became smaller than that of the one frozen for less than 5 weeks. To discover an indicator for evaluation of the conditioning of frozen and unfrozen beef, peptides produced during the storage of beef at 4°C were surveyed. A peptide, APPPPAEVPEVHEEV, was detected and seemed to be available as an indicator in the conditioning of beef.

View full abstract

The relationship between bacterial cellulose production and growth was investigated and the production was found to be associated with growth. Thus, it was expected that enhanced growth would lead to enhanced cellulose production. On the other hand, factors which promote the growth of and cellulose production by Acetobacter xylinum subsp. sucrofermentans BPR2001 were investigated and it was found that addition of p-aminobenzoic acid (PABA) has such effects. Therefore, mutants resistant to sulfaguanidine (SG), which is an analog of PABA, were bred from BPR2001. One of the mutants, BPR3001E, showed increased cell growth and had higher productivity, producing 9.7 g/liter of cellulose from 44 g/liter of fructose. The production is 40% higher than that of BPR2001.

View full abstract

Uricase from Cellulomonas flavigena SK-4 is an industrially useful enzyme for commercial formulations of hair coloring. The uricase production by recombinant Escherichia coli strain with a high cell density cultivation technique was described. Of three kinds of media, synthetic media with the feeding of a high concentration of glucose solution were suitable for high cell density cultivation. As for feeding, both biomass concentration and uricase productivity were increased by about two (61.2g dry cell weight (DCW)/liter)and three times (1037 U/ml broth), respectively, in 24h by continuous supply. In the case of feeding by a DO-stat method, however, cell concentration was comparable to continuous glucose supply but uricase activity was reduced. By supplying pure oxygen to compensate for oxygen limitation during cultivation, the highest values of 77.4g DCW/liter and 1113 U/ml broth of the uricase activity were achieved with the total cultivation time of 15h.

View full abstract

Sesamin is a specific inhibitor of Δ5 desaturation, the conversion from dihomo-γ-linolenic acid (20 : 3, n-6) to arachidonic acid (AA, 20 : 4, n-6). Previously, we reported that sesamin inhibited Δ5 desaturation of n-6 fatty acids in rat hepatocytes but not that of n-3 fatty acids, from 20 : 4 (n-3) to eicosapentaenoic acid (EPA, 20 : 5, n-3). In this study, we investigated the interaction of sesamin and EPA on Δ5 desaturation of both series and the n-6/n-3 fatty acids ratio by measuring actural fatty acid contents in vivo. Rats were fed three types of dietary oils ; 1) linoleic acid (LA, 18 : 2, n-6) : linolenic acid (LLA, 18 : 3, n-3) =3 : 1, n-6/n-3 ratio of 3 : 1 (LA group), 2) LA : LLA = 1 : 3, n-6/n-3 ratio of 1 : 3 (LLA group), 3)LA : LLA : EPA = 1 : 0. 5 : 3, n-6/n-3 ratio of 1 : 3. 5 (EPA group) with or without sesamin (0. 5% w/w) for 4 weeks. In all groups, sesamin administration increased the content of dihomo-γ-linolenic acid (20 : 3, n-6)in the liver and decreased the A5 desaturation index of n-6 fatty acid, the ratio of 20 : 4/20 : 3 (n-6). On the contrary, the Δ5 desaturation index of n-3 fatty acid, the ratio of 20 : 5 + 22 : 5 + 22 : 6/20 : 4 (n-3), was increased by the administration of sesamin. These results suggest that sesamin inhibits the Δ5 desaturation of n-6 fatty acid, but not that of n-3 fatty acid in rat livers. Sesamin administration decreased incorporation of EPA (n-3) and simultaneously increased the AA (n-6) content in the liver. The n-6/n-3 ratio in the liver was increased by administering sesamin under n-3 rich conditions, i.e., the LLA and EPA groups.

View full abstract

A CD8⁺ T cell clone specific to α_s1-casein, one of the major allergens in milk, is shown to inhibit its own production of interferon (IFN)-γ by producing interleukin (IL)-10. Anti-IL-10 antibodies enhanced the production of IFN-γ induced by the antigen plus antigen-presenting cells from 12h onward after initiating the culture. This enhancing effect was observed only when the cells were stimulated in the presence of the antigen-presenting cells. Neither IL-2 nor IL-4 abrogated this enhancing effect. This reveals a new regulating mechanism for IFN-γ production from CD8⁺ T cells.

View full abstract

Desorption behavior of β-lactoglobulin (β-Lg), one of the main constituents of fouling deposits in milk processing, from stainless steel surfaces during caustic and enzymatic cleanings was studied by using a glass column packed with stainless steel particles fouled with β-Lg. Both in caustic and enzymatic cleanings, the amount of β-Lg remaining on the stainless steel particles decreased according to first-order kinetics at the initial stage, and gradually reached a constant value. The desorption rate constant at the initial stage and the residual amount of β-Lg after 2h of cleaning were evaluated as the measures of cleaning efficiency under various conditions. In caustic cleaning, these two values were strongly affected by the concentration of NaOH. The initial desorption rate increased with increasing flow rate of the caustic solution, suggesting a mass transfer effect. In enzymatic cleaning, the maximum desorption rate constant was obtained at around the optimum pH for the enzyme reaction. The temperature dependence of the initial desorption rate constant was stronger in caustic cleaning than in enzymatic cleaning.

View full abstract

Improved conditions for the production and characterization of 1-arylpropane-1, 2-diols and related compounds were developed. Experimental conditions providing highly enhanced activity of pyruvate decarboxylase in bakers' yeast in the presence of pyruvate, thiamine pyrophosphate, and magnesium(II)salt were applied to the preparation of (R)-1-hydroxy-1-phenyl-2-propanone from benzaldehyde. Subsequent reduction with bakers' yeast efficiently afforded 1-phenyl-1, 2-propanediol (35%). The composition of its stereoisomers was precisely determined, and the major (1R, 2S)-isomer (89% of the total mixture) could be isolated by recrystallizing the corresponding benzoate. The analytical method for identifying the stereoisomeric composition was also effective for the determination of 5-phenyl-4-pentene-2, 3-diol, the biotransformation product from cinnamaldehyde, the vinylogous substrate of benzaldehyde. Furthermore, the structural characterization of 1-(2-furyl)propane-1, 2-diol, which was obtained from furfural (28%) by the action of brewers' yeast Saccharomyces cerevisiae (carlsbergensis), is described. The major (1S, 2S)-isomer could be isolated by recrystallizing the crude product.

View full abstract

A new enzymatic method for the measurement of serum and urine creatinine is described. The method is based on a novel microbial creatinine degradation pathway via N-methylhydantoin [Shimizu et al., Clin. Chim. Acta, 185, 241-252 (1989)]. By using two novel enzymes, N-methylhydantoin amidohydrolase and N-carbamoylsarcosine amidohydrolase, as key enzymes, coupled with a colorimetric procedure for hydrogen peroxide detection, the creatinine level can be measured. The results obtained for human serum and urine show good correlation with those obtained by a standard chemical method based on the Jaffe reaction. The new method is simple and specific, and shows excellent sensitivity and reliability.

View full abstract

Protective effects of bovine β-lactoglobulin (β-LG) from the degradation of β-ionone related compounds, retinol and β-carotene, was investigated. Retinol- and β-carotene-β-LG complex were incubated under the degrading conditions (heating, oxidation, and irradiation with a fluorescent lamp). The remaining amount of retinol and β-carotene was measured from UV spectra. It was found that β-LG protects β-ionone related compounds from degradation by heating, oxidation, and irradiation.

View full abstract

A cowpea globulin isolate was used as a substrate for transglutaminase (TGase), and the product was compared with native proteins in respect of its functional properties at pH 3-8. Foaming capacity was significantly increased (p ≤ 0.05) in the range pH 3-8as a result of the treatment with TGase. The emulsifying activity index was significantly (p ≤ 0.05) improved at pH 4, 6, and 7, while the emulsion stability was improved (p ≤ 0.05) in the range pH 3-6 for the treated samples.

View full abstract

Some di- and tridepsipeptides containing hydroxymethylbutyric acid were synthesized. A comparison of their NMR spectra with those of the degradation products from the Sarcodon scarbrosus depsipeptide enabled assigning the natural compound preferentially to be cyclo-Hmb-Ile-Hmb-Ala-Thr-. The configuration of the residue of Hmb-Ile is postulated to be L-L, although it could possibly be D-D.

View full abstract

A mixed culture we had isolated, which degrades biphenyl/poly-chlorinated biphenyls, is composed of two strains, Pseudomonas fluorescens KKL101 and Pseudomonas sp. strain KKS102. KKS102produces benzoic acid as a dead-end metabolite in the degradation of biphenyl. In this study we showed that KKL101 grew on benzoic acid as a sole source of carbon. This indicated a role of KKS102 in the growth of KKL101 and of KKL101 for the growth of KKS102in the mixed culture.

View full abstract

The chemical structures of the metabolites induced in oat leaves that had been inoculated with an incompatible race of crown rust fungus (phytoalexins) were examined. An HPLC analysis, using synthetic standards, demonstrates that they were a series of N-acyl5-hydroxyanthranilates named avenanthramides, where the acyl groups were p-coumaroyl (avenanthramide A), feruloyl (avenanthramide B), and 5-(4'-hydroxyphenyl)-penta-2, 4-dienoyl (avenanthramide L).

View full abstract

Schizophyllan was heated at 100°C in 85% dimethyl sulfoxide (DMSO) containing 0. 01M H₂SO₄ for various times, and fractionated by gel-permeation chromatography. Molecular weights (M_r) of the depolymerized products thus obtained were measured in water and DMSO by GPC-LALLS to estimate their conformations in water. The products with triple helical structure stimulated regeneration of Saccharomyces cerevisiae protoplast cells, while those of single chain conformation were totally inactive.

View full abstract

The ratios of oleic acid to linoleic and linolenic acids in phospholipid classes and triacylglycerol of rice grains were unexpectedly higher in the increasing order of cold tolerance among three varieties cultivated in Hokkaido. However, grain diglycosyldi-acylglycerol was found to be richer in linolenic acid, formed mostly within plastids, as the rice cultivars were more cold-tolerant.

View full abstract

The varietal differences in the rate of esterification of endosperm lutein by fatty acids during the storage of wheat seeds were determined for 138 wheat cultivars. Nine cultivars were found in which esterification did not proceed. The increase in free linoleic acid during storage was no different between the non-esterified and esterified cultivars. This suggests that the esterification of lutein is not caused by lipase, but rather by an unknown acylhydrolase which has a high substrate specificity to lutein.

View full abstract

The trans isomer of 2-(4-bromophenyl)-5-tert-butyl-2-thiono-1, 3, 2-dioxaphosphorinane competitively inhibited the specific binding of ³⁵S-tert-butylbicyclophosphorothionate to rat brain membranes with an IC₅₀ value of 0. 52μM, and showed insecticidal activity against houseflies with an LD₅₀ value of 2.4μg/fly. This compound and its analogues acted as noncompetitive GABA_A receptor antagonists (NGRAs), and phosphorus-containing cyclo-hexane skeletons may prove useful for the design of novel NGRAs.

View full abstract

The synthesis of p-boronophenylserine (BPS), a new water-soluble analogue of p-boronophenylalanine (BPA), was achieved from p-[(dihydroxy)boryl] benzaldehyde (1) in four steps. The key intermediate, oxazoline(4), was prepared by the reaction of the protected aldehyde(2) with ethyl isocyanoacetate(3), using sodium cyanide, and then transformed into syn- and anti-BPS.

View full abstract

Four phosphatidylcholines (PCs) containing linoleate (LA) and docosahexaenoate (DHA) in known positions were oxidized in an aqueous solution with or without chicken egg albumin. When PC was dispersed with albumin, PC containing DHA was more oxidatively stable than PC containing LA, and 1-palmitoyl (PA)-2-polyunsaturated fatty acyl (PUFA)-PC showed higher oxidative stability than a 1 : 1 mixture of 1, 2-diPUFA-PC+1, 2-diPA-PC. In an aqueous solution without albumin, however, the reverse results were obtained. Albumin had a strong inhibitory effect on the oxidation of PC in an aqueous phase, this action of albumin being more effective on PC containing DHA than on PC containing LA, and more effective on 1-PA-2-PUFA-PC than on 1 2-diPUFA-PC.

View full abstract

Sucrose and oils were detected by NMR spectroscopy in an intact maize seed. These compounds were located in the seed by an ¹H-NMR image and ¹H-NMR localized spectra using an NMR microscope. Oils were in the embryo and pericarp while most of the sucrose was in the endosperm. Oil composition was estimated by spin-simulation using a ¹³C-NMR spectrum.

View full abstract

Acetophenone was converted to phenol by A. glaucus MA0200. Production of phenol, which has a pungent flavor, seemed to give a contrary effect on the creation of flavor of molded Katsuobushi. Production of phenol is the process of degradation of acetophenone, also with a pungent flavor. It would play a role in the decreasing of the pungent flavor of Katsuobushi.

View full abstract

The α- and γ-tocopherol levels in the plasma of Japanese eel (Anguilla japonica) were 53.9μg and 1.3μg/ml of plasma, respectively. The α-tocopherol in the plasma was mainly distributed as very-low-density lipoprotein and low-density lipoprotein (LDL), while LDL and high-density lipoprotein constituted most of the γ-tocopherol. A highly positive coefficient of correlation was observed between the α-tocopherol and lipoprotein contents in Japanese eel Plasma.

View full abstract

The complete amino acid sequence of a proteinaceous cysteine proteinase inhibitor from the fruit of avocado (avocado cystatin)is presented. The protein consists of 100 amino acid residues and has a molecular mass of 11, 300 Da. Comparison of this sequence with sequences of plant cysteine proteinase inhibitors (phytocystatins), including oryzacystatins I and II from rice seeds, cowpea cystatin, and corn cystatin, showed that the avocado cystatin molecule has 60% and 54% residues identical with the two forms of the rice seed proteins, oryzacystatins I and II, respectively, and 64% and 63% with the cowpea and corn proteins, respectively. The totally conserved sequence, Gln-Val-Val-Ala-Gly, among several of the animal cystatins as well as phytocystatins, is at positions 47-51in the avocado cystatin molecule.

View full abstract

Four macrocarpals (macrocarpals A, B, E, and am-1) were isolated from the leaves of Eucalyptus amplifolia. Macrocarpal-am-1 is a new macrocarpal in which the isopentyl phloroglucinol chromophore is coupled with the 1, 10-secoaromadendrane skeleton. Its structure is elucidated by spectral techniques.

View full abstract

α-Galactosidase was purified by ion-exchange chromatographies on DEAE-cellulose and SE-cellulose columns from the culture filtrate of Penicillium purpurogenum No. 618. The final preparation was judged homogeneous by SDS-PAGE and its molecular mass and isoelectric Point were estimated to be 67kDa and 4. 1, respectively. The N-terminal amino acid sequence of the enzyme was analyzed and aligned with those of other α-galactosidases. In addition, the enzyme acted on the stubbed α-galactosyl residue connected to the β-1, 4-manno-oligosaccharide chain, indicating that this specificity was quite different from that of Mortierella vinacea α-galactosidase.

View full abstract

Arabidopsis thaliana and Nicotiana tabacum were transformed to blasticidin S (BS) resistance with BSD (the BS deaminase gene from Aspergillus terreus) using the Agrobacterium-mediated transformation method. Expression of BSD allowed direct selection of transformants by the fungicide, and both kinds of transgenic plants showed high level of resistance phenotype at 100ppm of BS sprayed on the leaves. Using Botrytis cinerea, the causal fungus of gray mold disease, it was exemplified that application of BS could control the disease in transgenic tobacco with negligible phytotoxicity.

View full abstract

Induction and repression of tyrosine phenol-lyase (TPL; EC4.1.99.2) of Erwinia herbicola AJ2985 were examined on the transcriptional level and it was shown that transcription of tpl was increased by the addition of tyrosine and decreased by the addition of glucose in the medium. The 5' flanking region of its gene, tpl, was analyzed and its transcriptional start point was determined. A presumed -35, -10 promoter region, TyrR box, and operator-like region were also found in this region.

View full abstract

Methyl esters of 3-epi-GA₃ and 3-epi-GA₁ were efficiently pre-pared from methyl esters of GA₃ and GA₁, respectively, by highly selective epimerization of the 3-hydroxyl function with a base in a low-polar aprotic medium.

View full abstract

Ovokinin, a vasorelaxing octapeptide derived from ovalbumin, significantly lowered the systolic blood pressure of spontaneously hypertensive rats (SHR) when orally administered as an emulsion in 30% egg yolk at a dose of 25mg/kg, this effect being larger than that of the peptide administered as a solution at a dose of 100mg/kg. Egg phospholipid, especially phosphatidylcholine, showed essentially the same effect as egg yolk. However, egg neutral lipid was ineffec-tive. Soybean phospholipid was less effective than egg phospholipid in potentiating the antihypertensive activity of ovokinin.

View full abstract

Oligosaccharides (from trisaccharide to decasaccharide) in yacon tuberous roots were purified by charcoal-Celite column and gelfiltration chromatographies. The oligosaccharides were confirmed to be β-(2→1)fructooligosaccharides with terminal sucrose (inulin type oligofructans) by using enzymatic, ¹³C-NMR, and methylation analyses.

View full abstract

BbrPI, an extracellular serine proteinase inhibitors of B. brevis HPD31, is activated by proteolytic processing of an inactive precur-sor. To discover the physiological role of BbrPI, its deficient mutants were genetically constructed. Although the BbrPI deficient mutant had a higher extracellular proteinase activity than the parent strain, it grew normally. The BbrPI deficient mutant showed higher sensitivity to added trypsin than that of the parent. These observa-tions suggest that the BbrPI may play a role in cellular protection from the attack of exogenous proteinases.

View full abstract

The cytokine receptor homologous (CRH) region of the murine granulocyte colony-stimulating factor (G-CSF) receptor was secreted using a Escherichia coli maltose binding protein (MBP) fusion system. The CRH region was prepared from the periplasmic fraction by G-CSF affinity column chromatography and restriction protease factor Xa digestion, and was purified to homogeneity. The purified CRH region specifically bound G-CSF, with an apparent dissociation constant (Kd) of about 1. 5×10^-9 M. A 1:1CRH·G-CSF complex was established by gel-filtration high pressure liquid chromatography (HPLC). However, a 2:1 stoichiometric complex was not established, as in the case of the growth hormone (GH)receptor [Recent Prog. Hormone Res., 48, 233-275 (1993)].

View full abstract

Syntheses of two possible stereoisomeric epoxy lactones (20S, 21R)- and (20R, 21S)-1 that have been proposed for epoxy-rollin A, a structural representative of biosynthetic precursors of tetrahydrofuran annonaceous acetogenins, are described. Protected dihydroxy compound 4, which is the latent epoxy moiety of (20S, 21R)- and (20R, 21S)-1, was prepared by an 8-step sequence via Sharpless asymmetric dihydroxylation, starting from allyl alcohol 6. Preparation of γ-lactone moiety 5 was conducted by the method reported earlier. A palladium-catalyzed cross coupling reaction of 4 with 5 gave enyne 3, which, by a 3-step sequence, was converted into (20S, 21R)- and (20R, 21S)-1. The ¹³C-NMR and mass spectraldata of the two synthetic diastereoisomers are not in accordance with those recorded for epoxyrollin A. Consequently, the structure of epoxyrollin A needs to be revised.

View full abstract

The outer membrane protein profiles of a toluene-tolerant mutant, Pseudomonas aeruginosa, strain PAK103, were compared with those of its parent strain PAO1161. Protein F (OprF), the most abundant outer membrane protein in the parental strain PAO1161, was missing in the toluene-tolerant strain PAK103. The absence of OprF may lead to the loss of toluene diffusion across in the outer membrane of the mutant cells.

View full abstract