The effects of lecithin addition in oil or water phase on the stability of oil-in-water emulsions made with 0.1 wt%, whey protein and 10 wt% n-tetradecane at neutral and acidic pH were studied by monitoring the gravitational creaming and phase separation. The effects of lecithin addition on the interfacial behavior of β-lactoglobulin were also studied to compare with the results of emulsion stability. At neutral pH, crude phosphatidylcholine (PC) from egg yolk or soybean increased the stability of the emulsion made with protein and lowered the interfacial tension of protein films more effectively than pure egg PC. A more remarkable effect on both the emulsion stability and the interfacial tension was found when crude PC was added in the oil phase rather than in the water phase. The purity of lecithins and the way to add them are suggested to be very important to make a stable emulsion with protein. On acidic pH (4.5 or 3.0), the increased creaming or phase separation in a whey protein-stabilized emulsion, but the lowered interfacial tension of β-lactoglobulin films, were found upon the addition of pure or orude PC in oil or water phase. These results suggest that in acidic pH, densely packed films may be formed on a planar oil-water interface, but not on adsorbed layers around oil droplets in an emulsion.

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Certain plasmids in Enterococcus faecalis encode a mating response to recipient-produced peptide sex pheromones. Targeted disruption of tra genes on pPD1 suggested that TraA plays a central role in the plasmid-specific pheromone signaling pathway. TraA functioned as a negative regulator for the pheromone-inducible conjugal transfer. Complementation analysis of pPD1 tra gene mutants by pAD1 suggested that the pheromone binding function of TraC was non-specific between these plasmids, but the function of TraA and the pheromone shutdown function of TraB are plasmid-specific.

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The presence of resveratrol (3, 5, 4'-trihydroxystilbene) and its β-glucoside, piceid (resveratrol-3-β-D-glucopyranoside), together with their isomers in wine appears to be one of the beneficial factors conferring a protective effect against cardiovascular disease through red wine ingestion. A total of 42 red and white wines was collected in arears from Hokkaido to Kyushu in Japan. The wines were fractionated with a C₁₈ Sep-pak cartridge, and the active principles were eluted with ethyl acetate. Crude trans- and cis-piceid were extracted from a Chinese medicine, 'Kojohkon' (Polygonum cuspidatum), and their retention times and UV absorption were confirmed by HPLC. trans- and cis-Resveratrol, and trans- and cis-piceid were analyzed in a short C₁₈ HPLC column, and cis-resveratrol was quantified from the amount of cis-isomer converted from authentic trans-resveratrol that had been treated by UV irradiation. The content of piceid is shown as the resveratrol equivalent. The average content of total stilbene compounds was 4.37 mg/liter in red wines, while only 0.68 mg/liter in white wines. Red wines made from Pinot noir, Merlot, and Zweigeltrebe grapes all had a high resveratrol content.

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Effects of cytokinins were studied on rotenone-sensitive NADH dehydrogenase in mitochondria from fresh potato tubers (Solanum tuberosum), in consideration of the operation of external and rotenone-insensitive internal NADH dehydrogenases that has not been fully accounted for in previous studies. In submitochondrial particles (smp), zeatin was only weakly active, and zeatin riboside (ZR) was inactive. Inhibition rates at 400 μM of isopentenyladenine (iP) and isopentenyladenosine (iPA) were 45% and 30%, respectively, and that of BA (BA) was 64%. In intact mitochondria, the inhibition by iP and BA significantly increased, I₅₀ being 50 and 250 μM, respectively, but that by zeatin and iPA decreased. A structur-activity study showed that hydrophobic and steric factors are important for the activity. Cytokinins inhibited the electron flow via natural quinone more strongly than that via synthetic quinone. These results suggest that among the cytokinins the species that can regulate the electron transport is iP rather than its riboside or zeatin.

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Gene expression of apolipoproteins (apo) A-I, A-IV, and B, the predominant protein components of chylomicrons, was investigated in the residual ileum after a massive small bowel resection in rats. A Northern blot analysis showed that the apo A-IV mRNA level, but not the apo A-I and B mRNA levels, in the ileum was significantly higher in the resected rats than in the sham-operated rats 24 h and 2 wk post-surgery. RT-PCR coupled with a primer extension assay revealed that the apo B-48 mRNA/apo B-100 mRNA ratio, i.e., apo B mRNA editing, in the ielum was unchanged by the resection. It is thus concluded that, among the major intestinal apolipoproteins, apo A-IV is the only one whose gene expression is influenced by loss of the proximal intestine.

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The effect of activating the renin-angiotensin system on the metabolism of angiotensins (ANGs) in normotensive human plasma was investigated. In normotensive supine human plasma, four peptides with in vitro angiotensin I-converting enzyme (ACE) inhibitory activity which correspond to the sequence of ANG (3-8), ANG (4-8), ANG (5-8), and ANG (3-4) existed at a concentration of > 39 fmol/ml of plasma. When activating the renin activity by keeping upright in posture for 60 min, ANG II and the four peptides significantly increased as compared with the levels in the supine posture, except for ANG I. In particular, Val-Tyr corresponding to ANG (3-4) in the upright posture was about 4-fold more than the value in the supine posture, and was predominantly present (447 fmol/ml of plasma) as well as ANG I. As a result of in vitro degradation tests on ANGs, ANG (3-4) was produced from ANG I, and not from ANG II, III or (3-8), during the 30-min incubation.

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The oxidation of the tryptophan residues of rye seed chitinase-a (RSC-a) and its isolated catalytic (Cat) domain by N-bromosuccinimide (NBS) was investigated in the absence and presence of oligomers of N-acetylglucosamine (GlcNAc)_n. Based on the reactivity toward NBS at pH 5.9, the seven tryptophan residues present in RSC-a are grouped into highly reactive (HR-), low reactive (LR-), and unreactive residues. Analyses of the peptides from 1 tryptophan- and 3 tryptophan-oxidized RSC-a showed that the HR-residue is Trp23 and the LR-residues are Trp131 and Trp141. The chitin-binding ability of RSC-a was lost upon the NBS oxidation of Trp23 at pH 5.9 or pH 7.0. This oxidation was prevented by (GlcNAc)₃, which induced a high UV-difference spectrum with maxima at 284 and 293 nm. On the other hand, the chitinase activity of the Cat domain was greatly reduced by the NBS oxidation of Trp131 and Trp141 at pH 5.9, while in the NBS oxidation at pH 6.4, approximately one tryptophan residue was oxidized and about half of the activity was retained. The NBS oxidation of the isolated Cat domain at pH 5.9 was protected by (GlcNAc)₄, which induced a UV-difference spectrum with maxima at 284 nm and 293 nm as well as a small trough around 300 nm, similar to that observed in RSC-c. From these results and the previous result that Trp72 in RSC-c is involved in the substrate-binding, it was suggested that Trp23 is highly exposed on the surface of the RSC-a molecule and involved in the chitin-binding, while Trp131 is involved in substrate-binding in its enzyme action.

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The capacitance of suspensions of cultured rice cells (Oryza sativa L. ssp. japonica), grape cells (Vitis sp.), and CH27 cells originated from murine B-cell lymphoma was measured in the frequency range of 0.2 to 10 MHz. The relationship between the increase in capacitance caused by the presence of cells at 0.4 MHz, ΔC, and the cell density was linear. Measurement of capacitance was useful in measurement of transitional changes in cell volume under external osmotic stress when sucrose was added. From the course of volume changes with such stress, the water permeabilities of the plasma membrane, L_p, were measured to be 0.015, 0.020, and 0.090 pm/(s·Pa) at 25°C, for rice cells, grape cells, and CH27 cells, respectively. The smaller L_p for plant cells seemed to explain why preservation of plant cells by freezing is more difficult than for animal cells. From the temperature dependence of L_p, the apparent activation energies were calculated to be 12.0±2.9 and 13.0±5.2 kcal/mol for rice cells and CH27 cells, respectively.

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Dielectric relaxation of water molecules was measured in the frequency range from 0.2 to 20 GHz for aqueous solutions of urea, formamide, alcohols, and saccharides. The relaxation behavior was described well by the Debye equation with a single relaxation process in most cases. The static permittivity of solution and relaxation time of water in solution changed linearly with solute concentration. The relaxation time shift of water molecules through the existence of solute was correlated well to the first virial coefficient of the activity coefficient of water suggesting the close relationship between dielectric relaxation time and aqueous solution structure.

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A convenient detection of sugar chains in Taka-amylase A (TAA) was done by using 40 μg of enzyme, where a decrease in the UV absorption of NaIO₄ during the periodate oxidation reaction was monitored. The periodate-oxidized sugar chain was labeled with a fluorescent reagent, N-1-ethylenediaminonaphthalene (EDAN), by incubation at pH 9.5 and 30°C for 1h. The excess EDAN was removed by either quenching with o-phthaladehyde or Bio-Gel P-2 gel adsorption. Among the peptide fragments preparbd from the EDAN-labeled TAA, a fluorescent peptide corresponding to the sugar chain was distinguished by the ODS column. These results suggest that periodate oxidation and subsequent fluorescent labeling were useful for the sensitive analysis of various glycoprotein samples.

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An α-amylase from Aspergillus oryzae, Taka-amylase A (TAA), was cleaved into peptide fragments by an acid protease. Inactivation of TAA was greatly retarded by the addition of α-cyclodextrin or Ca²⁺. TAA peptide fragments were separated into two groups having no and high affinity to the substrate, soluble statch. This separation was done by the forced affinity chromatography method by a column of epichlorohydrin cross-linked soluble starch gel. Three peptides were isolated from the high-affinity fragments, purified by the ODS-120T column, and their amino acids were sequenced. Peptides I, II, and III originated from α2-helix, α3-helix, and β2-sheet, respectively, and all of these were located in the (β/α)₈ barrel of the main domain of TAA molecule. A stereo graphic view showed that Peptides I-III were at the cleft near the catalytic site. Occurrence of a Trp residue in all three peptides strongly suggested that Trp was very important in the binding of TAA to the substrate, soluble starch.

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An unidentified growth factor (UGF) was separated from shochu distillery by-products (SDBP) and its effect on the growth of a primary chick muscle cell culture was investigated. Chick muscle cells were isolated from fertile eggs (13-day-old embryos) of commercial broilers. UGF was separated on Sephadex LH-20 with a solvent system of water-methanol-ethylene dichloride (10:90: 20, v/v), and the fraction eluted between 136 and 164 min was collected (fraction I). Fraction I was further purified by HPLC with an Inertsil ODS-2 column using a solvent system of methanol-butanol (80:20, v/v). Three fractions having retention times of 3.76, 4.57, and 5.12 min were collected and are referred to as fraction A, B, and C, respectively. In experiment 1, chick muscle cells were cultured in an m-199 medium containing 0.001, 0.01, or 0.1% of fraction I. In experiment 2, chick muscle cells were cultured with 0.01 or 0.005% of each fraction A, B, and C. Creatine kinase (CK) activity, protein and DNA contents were measured as indices of myotube growth, cell growth and cell proliferation, respectively. N^τ-mbthylhistidine (N^τ-MH) release from the muscle cell was also measured to observe the effect on proteolysis. In experiment 1, the protein content was significantly (p < 0.05) increased by fraction I, despite the low dose level. CK activity was significantly (p < 0.05) higher than the control when 0.001% of fraction I was added to the medium. However, increasing the level beyond 0.01% did not further increase the CK activity. The DNA content was not significantly changed. In experiment 2, the protein content, CK activity, and DNA content were significantly (p < 0.05) higher when fractions A and B were added to the medium. However, this was not the case when fraction C was added. N^τ-MH release was significantly (p < 0.05) higher when fraction A was added, but, was significantly (p < 0.05) lower when fraction B was added, while fraction C had no effect on N^τ-MH release. The present results show that SDBP contained two growth-promoting factors for a primary chick muscle cell culture, although their modes of action may be different.

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Nigrosporin A and B, two new phytotoxic and antibacterial metabolites were isolated from a culture filtrate of Ngrospora oryzae. The active principles were absorbed on XAD-2 resin and purified by suceessive ODS-HPLC. The structures were identified by spectroscopic and derivatization analysis as naphthoquinone derivatives. The substances showed phytotoxic activities, such as root elongation inhibition, necrotic effects, oxygen evolution inhibition, starch synthesis inhibition, and CO₂ fixation inhibition at concentrations of 10-100 ppm. They also showed growth inhibition activity against Bacillus subtilis in a disc diffusion assay as well as when compared with streptomycin.

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Pseudomonas sp. OS-ALG-9 produces several kinds of alginate-degrading enzymes both intra- and extracellularly. As a second alginate lyase of this bacterium, the gene encoding alyII has been cloned in Escherichia coli JM109 by shotgun techniques and then sequenced. The alyII gene has an open reading frame of 2141 bp encoding 713 amino acid residues with a calculated molecular mass of 79, 803 Da. The deduced amino acid sequence did not show any extensive similarity with those of other known alginate lyases, however, hydrophobic cluster analysis showed that alyII belonged to class 3 of alginate lyases. The alginate lyase from E. coli harboring the alyII gene showed a single active band, which coincided with one of four major alginate lyases from the crude cell extracts of Pseudomonas sp. OS-ALG-9 on a zymogram.

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We constructed an efficient system for synthesis and secretion of human interleukin-2 (IL-2) by Bacillus brevis. The secretion vector we constructed had strong promoters and contained the region coding for the signal peptide of the gene for B. brevis 47 cell-wall protein, followed directly by the gene encoding mature IL-2. Modification of the signal peptide and use of a protease-deficient mutant of B. brevis HPD31 increased productivity. When the signal peptide was more basic near its amino terminal and more hydrophobic in the middle region, IL-2 production increased 20 fold. Production by the mutant harboring the secretion vector was four fold that of the parent harboring the same plasmid. The yield of IL-2 iricreased further to 0.12 g/liter, when cultural conditions were made optimal, such by the addition of Tween 40 to the medium. The IL-2 produced by B. brevis had the same biological activity as authentic IL-2. Biologically active human IL-2 was produced efficiently and secreted directly into the medium by B. brevis.

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Acetobacter xylinum produces both cellulase and bacterial cellulose, but some report believed that this cellulase activity does not decrease the degree of polymerization (DP) of bacterial cellulose during cultivation. A. xylinum subsp. sucrofermentans BPR2001 produces two enzymes that hydrolyze CM-cellulose and cellotriose, respectively. We examined the effect of the two cellulase activities on the DP of bacterial cellulose when bacterial cells were cultured with agitation at pH 4, where little cellulase is produced, and at pH 5, where much cellulase is produced. The weight-average degree of polymerization (DP_w) of bacterial cellulose remained in the range of 14, 000 of 16, 000 during cultivation at pH 4, but at pH 5, the DP_w decreased from 16, 800 to 11, 000. The mechanical strength of a sheet prepared from the bacterial cellulose produced at pH 4 was higher than those of BC produced at pH 5. These results suggest that the two cellulase activities cause the decrease in DP and deterioration of physical properties of bacterial cellulose seen during cultibation.

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The structures of N-linked sugar chains (N-glycans) of storage glycoproteins in soybean seeds have been identified. Eight pyridylaminated (PA-) N-linked sugar chains were derived and purified from hydrazinolysates of the storage glycoproteins by reverse-phase HPLC and size-fractionation HPLC. The structures of the PA-sugar chains purified were first identified by two-dimensional PA-sugar chain mapping and ion-spray mass analysis, considering the results of sugar composition analysis or sequential exotlycosidase digestion. The deduced structures were further analyzed by ion-spray tandem mass spectrometry and 500 MHz ¹H-NMR spectrometry. The eight structures fell into two categories; the major class (96.6%) was a typical high mannose-type, the minor class was a xylose containing-type (Man₃Xyl₁GleNAc₂, Man₃Fuc₁Xyl₁GlcNAc₂; 3.4%).

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An 8', 8', 8'-trideuterated analog of abscisic acid (ABA) was diastereoselectively synthesized as a new analog of ABA that is resistant to 8'-hydroxylation, the first metabolic reaction of ABA, owing to the primary kinetic isotope effect. (+)-8', 8', 8'-Trideutero-ABA showed long-term activity in the rice elongation assay. The rate of metabolism of this analog in rice cell suspension culture was about two fold slower than that of (+). ABA. The concentration of 8', 8'-dideuterophaseic acid produced was about 1/3 that of phaseic acid converted from (+)-ABA. This result indicated that the long-lasting activity of the (+)-trideutero-ABA in the rice assay was the result of the delayed 8'-hydroxylation as expected.

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An efficient production strain for L-threonine fermentation was derived from Escherichia coli by multiple rounds of mutation programs that aimed at deregulation of the L-threonine biosynthetic pathway and blocking of L-threonine degradation pathways. When the optimum amount of DL-methionine was added, this strain KY10935, an L-methionine auxotroph, gave 100 g/liter L-threonine after 77 h cultivation. In this strain, key enzymes in the L-threonine biosynthetic pathway were highly derepressed, but some were inhibited by lower concentrations of L-threonine than the accumulated level. Such incomplete deregulation of the pathway was accounted for by the intracellular concentration of L-threonine being lower than the extracellular level. In an assessment of L-threonine transport in terms of phenotypic growth responses to the amino acid, L-threonine-auxotrophic mutanis with a lesion in the L-threonine operon were derived from strain KY10935 by selection for auxotrophy for dipeptide L-alanyl-L-threonine or glycyl-L-threonine, the transport systems of which were different from those of L-threonine. All three independent mutants isolated needed an extraordinarily high concentration (10mg/ml) of L-threonine, but grew in the presence of a low concentration (10μg/ml) of either dipeptide, indicating that strain KY10935 had impaired L-threonine uptake. These results suggested that the strain had an unusual mechanism of L-threonine hyperproduction: the inability to take up L-threonine that had accumulated extracellularly decreased the steady-state level of intracellular L-threonine, freeing the remaining regulatory steps of feedback inhibition.

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Sulfated glycopeptides in ovomucin, chalazae and yolk membrane were found to activate cultured macrophage-like cells, J774.1, and TGC-induced macrophages from the peritoneal cavity of male mice. The mactophage-stimulating activity was estimated by the growth and morphology of the cells, H₂O₂ generation, and interleukin-1 (IL-1) production from the cells. The in vitro culture assay with macrophages showed that the protease digests of ovomucin, yolk membrane, and chalazae induced morphologic alteration and increased H₂O₂ generation and IL-1 production in lower concentration (100μg/ml). The isolation of the components having macrophage-stimulating activity was attempted to elucidate the molecular mechanism. The O-linked carbohydrate chains, consisting of N-acetylgalactosamine, galactose, N-acetylneuraminic acid and sulfate, in the sulfated glycopeptide were identified as a component having macrophage-stimulating activity.

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One of the three isoforms of an enzyme degrading L-cystine was purified to homogeneity from broccoli (Brassica oleracea var. italica) inflorescences, with use of a sensitive assay based on derivatization of a reaction product with monobromobimane. The reaction product with a thiol group was found to be thiocysteine from results of liquid chromatography-mass spectrometry and high-resolution mass spectrometry. Pyruvate was also a reaction product, formed in equimolar amounts. The purified enzyme catalyzed β-elimination of L-cystine to yield thiocysteine, pyruvate and possibly ammonia, so it was cystine lyase a. L-Cystine but not D-cystine was a substrate of the enzyme. S-Methyl L-cysteine sulfoxide and S-ethyl L-cysteine sulfoxide were substrates but were less suitable than L-cystine. L- and D-cysteine and also cystathionine were not substrates. The purified enzyme (M 186, 000) was composed of four identical subunits (M_r 45, 000) and was pyridoxal 5'-phosphate-dependent.

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Plant growth regulators (PGRs) including gibberellins (GAs) were examined for their effects on shoot growth and flowering of a perennial paddy weed, Sagittaria pygmaea Miq. Among PGRs tested, only GAs (A₁, A₃, A₄, and A₅), AC-94377 [1-(4-chloro-1, 3-dihydro-1, 3-dioxo-2H-isoindol-2-yl)cyclohexanecarboxamide] and 2, 6-diisopropylphenoxyacetic acid (DIPA) promoted both shoot growth and flowering. Structural requirements of GAs for promotion of flowering seemed to be different from those for shoot growth of the weed. In addition, since the course of flowering induced by DIPA was clearly different from that observed in plots treated with GA₃ or AC-94377, different mechanisms may be involved in promotion of flowering.

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The cytoprotective effect of green tea extract and its phenolic compounds against 1, 4-naphthoquinone-induced hepatotoxicity was evaluated in primary cultured rat hepatocytes. After exposure to 1, 4-naph-thoquinone, lactate dehydrogenase (LDH) leakage and cell viability were both improved by the presence of the tea extract and tea polyphenols. This cytoprotective effect was related to the structure of tea polyphenols, the galloyl group of (-)-epigallocatechin-3-gallate and (-)-epicatechin-3-gallate being particularly effective. The production of liquid peroxidation by 1, 4-naphthoquinone was not inhibited by the tea extract nor by tea polyphenol addition. After 2 h of incubation, the protein thiol concentration was reduced by 1, 4-naphthoquinone, but this reduction was prevented by the tea extract and tea polyphenols.The reduction in protein thiol content of the cells closely paralleled the LDH leakage and loss of cell viability. These results suggest that the mechanism of protection by tea polyphenols against 1, 4-naphthoquinone-induced toxicity to rat hepatocytes was due to the maintenance of protein thiol levels.

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Reinvestigation of the opisthonotal gland secretion of the mold mite, Tyrophagus putrescentiae, resulted in the isolation of a new monoterpene lactone, whose chemical structure was elucidated as (E)-2-(4'-methyl-3'-pentenylidene)-4-butanolide (3), to which we gave the trivial name β-acariolide in relation to β-acaridial {1, (E)-2-(4-methyl-3-pentenylidene)-butanedial}. The compound was synthesized by LiAlH₃(OEt) reduction of 1 and subsequent oxidation involving simultaneous cyclization by using Ag₂CO₃ on Celite. Both the E- and Z-isomers of β-acariolide (3 and 4) were also prepared by the reaction of α-ethoxaly-γ-butyrolactone (6) and 4-methyl-3-pentenal under basic conditions. Their NMR spectra were compared with each other, and the geometry of the pentenylidene double bond of the isolated compound was concluded as being E.

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The water-soluble lignin in LEM (the extract of the solid culture medium of Lentinus edodes mycelia) has been known to have antiviral and immunopotentiating activities in vivo and in vitro. The water-soluble lignin rich fraction (JLS-18) was prepared from LEM using ultrafiltration and hydrophobic column chromatography. JLS-18 showed about 70 times higher antiviral activity than LEM in vitro. JLS-18 activated the cytotoxicity of NK cells and macrophages, and activated T cells in vitro. JLS-18 also induced interleukin 6 (IL-6) secretion from human leukocytes infected with Sendai virus in vitro. These data showed that JLS-18, the water-soluble rich fraction of LEM, had antiviral and immunopotentiating activities.

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Mutation of Asp51 of a base-nonspecific RNase, RNase Rh, to Ser, Thr, or Gln makes the enzyme more preferential for the dinucleoside phosphate (XpY) having G and C at the 5'-side (X). On the other hand the mutation of one of the B1 site components, Tyr57 to Trp, and Trp49 to Phe makes the enzyme more preferential for purine bases and pyrimidine bases, respectively. In this study, to obtain more specitic RNases and RNases with different base specificity, we prepared double-mutant enzymes that have Ser, Thr, and Asn at the 51st position and Trp at the 57th position or Phe at the 49th position, and their enzymatic specificities were studied with XpYs as substrates. The double-mutant enzymes D51SY57W and D51TY57W are lmore guanylic atid preferentiaI than the mother single-mutant enzymes, D51S and D51T, respectively. They are extremely guanylic preferential RNases. D51NY57W is more a guanylic acid preferential enzymb than D51N, but cytidylic acid preferente is of a similar order to that of D51N. The double mutant enzymes D51NW49F and D51TW49F showed an increased cytidylic acid preference as well as guanylic acid preference as compared to the mother single-mutant enzymes, D51T and D51N. The results of analysis of base specificity by the release of mononucleotides from RNA and the rates of hydrolysis of homopolynucleotides led to the same conclusion as in the case of the hydrolysis of XpY.

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The main structure of shark type I collagen is similar to that of land mammals, with a partial difference in amino acid sequence and post-translational modification. By static light scattering, the weight-average molecular weight of shark collagen (7.52×10⁵) suggests the presence of some aggregated molecules, oligomeric collagen. The self-assembly curve of shark collagen had a shorter lag phase and a longer growth phase than that of pig collagen. The optimum temperature and pH of shark collagen self-assembly is different from that of pig collagen.

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A carboxymethylated derivative of a linear (1→3)-β-D-glucan (CMCD) from Alcaligenes faecalis var. myxogenes acted directly on mouse peritoneal macrophages and mouse lymphoma P388D1 cells, and induced a growth suppressing activity for bovine artery endothelial cells (BAEs) from themselves at a concentration of 100μg/ml. The suppressing activity was also detected in the mouse serum administered as an i.p. injection of CMCD at a dose of 100mg/kg, suggesting that the growth suppressing activity was induced from macrophages potentiated by CMCD in vivo.

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Arbutin cinnamate was synthesized from arbutin (4-hydroxy-phenyl β-D-glucopyranoside) and vinyl cinnamate by regioselective transesterification with a bacterial lipase in acetonitrile. The product was identified by NMR and FAB-MS analyses. These spectra showed that one ester bond was formed between the primary alcohol moiety of the D-glucose of arbutin and the carboxyl residue of cinnamic acid. Furthermore, plant pigments such as isoquercitrin (quercetin 3-O-β-D-glucopyranoside) and callistephin (pelargonidin 3-O-β-D-glucopyranoside) were also converted to their corresponding cinnamate esters in the same manner.

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Two new acylated anthocyanins were isolated from beninabana, Brassica campestris var. chinensis, in addition to two known anthocyanins. The structures were established by spectral analyses.

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A novel and efficient procedure named "reducing end modification method" was developed for manufacturing high purity maltooligosaccharides. By the method, high purity maltose and maltotetraose were prepared from starch. Starch was liquefied, debranched, and oxidized with sodium hypochlorite at the reducing end. The reaction mixture was treated with β-amylase or maltotetraose-forming amylase from Pseudomonas stutzeri IFO-3773, resulting in the production of high purity maltose or maltotetraose, oxidized maltooligosaccharides, and oxidized undigested dextrin. High purity maltose (maltose content, 99.9%) or maltotetraose (maltotetraose content, 95%) was obtained very effectively from the reaction mixture by chtomatography on a strong acid cation exchange resin (Na⁺).

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An aminopeptidase A (EC 3.4.11.7) was purified to homogeneity from Bacillus lichenformis NS115 and its enzymatic properties were characterized. The enzyme had an apparent molecular mass of 64 kDa, consisting of heterodimeric 42 kDa and 22 kDa subunits, and is a new enzyme from N-terminal analysis of heavy and light subunits. The light subunit had no catalytic activity against the substrate and apparent K_m values of heavy and whole enzyme were 0.26 and 0.087 mM of γ-glutamyl-p-nitroanilide, respectively.

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The effect of orally administering cabbage juice on tumor necrosis factor α (TNF) and interleukin-1 (IL-1) productivity was studied in resident peritoneal macrophages from normal and hepatoma-bearing rats. The productivity of TNF and IL-1 was stimulated by gastric intubation of cabbage juice in the normal state, but not in the hepatoma-bearing state where the production of these cytokines had already been stimulated. From these results, cabbage may contain some effective component(s) that can be absorbed from the gastrointestinal tract to stimulate the production of TNF and IL-1.

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Vibrio anguillarum is a pathogenic microorganism of vibriosis, an infectious disease found in various fish species. A mouse hybridoma clone, named C5, that produced a monoclonal antibody to V. anguillarum was established. The specific reaction of C5 antibody with V. anguillarum was confirmed by the pre-adsorption effect of the V. anguillarum cells in ELISA and a cell immunoprecipitation experiment. Western blotting analysis indicated that the C5 antibody recognized a high molccular weight stubstance extracted from cells with detergents.

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Antioxidant activity of ferulic acid β-glucuronide, which is prepared from the plasma of feruloyl arabinose fed rats, in the CuSO₄-induced LDL autoxidation system was studied. It has been found that absorbed ferulic acid occurred as the β-glucuronide and that the antioxidant activity of ferulic acid β-glucuronide, which has not only the hydrophobic ferulic acid moiety but also a hydrophilic sugar moiety, is stronger than ferulic acid in the LDL oxidation system.

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ρ-Aminobenzoic ethyl ester (ABEE)-derivatized monosaccharides were separated by HPLC with a trifluoroacetic acid (TFA) solution or borate buffer as the eluent. In the case of the TFA solution, ABEE-derivatized monosaccharides of the neutral and amino sugars found in animal glycoproteins were separated in a simultaneous analysis. In the case of the borate buffer, ABEE-derivatized monosaccharides of identical molecular weights such as ABEE-Gal, -Glc, and -Man were separated as stereoisomers. Glucuronic acid and galacturonic acid were detected and separated within 8 min. The relationship between the peak areas and the amounts of ABEE-derivatized monosaccharides was linear in the range of 1 to 1000 pmol.

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A ceramics preparation (Cleansand-205), which was coated with a mixture of the oxides of Si, Al, Ti, and Ag, was found to inactivate Lactobacillus phage PL-1 suspended in a buffer solution. The inactivation of phage was dependent on the amounts of Cleansand-205 added, and the reaction obeyed almost first-order reaction kinetics. The phage inactivation was considerably accelerated by the presence of light.

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The nucleotide sequence of 1981 bp cDNA containing the entire coding region of a human placental fructose-6-phosphate, 2-kinase/fructose-2, 6-bisphosphatase was determined. The sequence encodes 469 amino acids and, based on homology to the rat testis enzyme, appears to be the testis-type isozyme expressed in placenta. The enzyme was expressed in Escherichia coli BL21 (DE3) by using a T7 RNA polymerase-based expression system and purified to homogeneity. The expressed enzyme was bifunctional with specific activities of 75 and 80 mU/mg of kinase and phosphatase, respectively. Kinetic parameters of the expressed enzyme are similar to those of the rat testis enzyme.

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Water extracts from meats and offals were incubated with a macrophage cell line (RAW 264.7), and nitrite in the medium was measured as an index of the macrophage stimulating activity. Ten of 38 water extracts had macrophage stimulants and chicken meat, chicken gizzard, cattle reticulorumen, swine stomach, and swine cerebrum had high activities.

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About 80% of radioactivity was recovered in asymmetrically labeled sucrose from UDP-[¹⁴C]glucose or [¹⁴C]fructose with recombinant mung bean sucrose synthase expressed in Escherichia coli harboring pEB-01. This high recovery is due to the fact that the enzyme conserving the activity of sucrose synthase has a similar affinity for UDP-glucose and fructose to an intact enzyme from the mung bean, but a lower affinity for sucrose.

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Biodegradabilities of chelating agents were tested with activated sludge. Ethylenediaminetetraacetic acid (EDTA) remained intact in the effuent even after acclimation for 100 days, but propanediamine-N, N'-disuccinic acid (PDDS) and nitrilotriacetic acid (NTA) were biodegraded after acclimation for 5 and 23 days, respectively. Optical isomers of ethylenediamine-N, N'-disuccinic acid (EDDS) had different biodegradabilitibs: SS- and RS-isomers were susceptible to biodegradation, but the RR-isomer was resistant. SS-isomer was degraded even by activated sludge without acclimation.

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The staphylococcal Panton-Valentine leukocidin (PVL) genes [luk-S-PV-lukF-PV] existed in a hexagonal phage-like particle (φPVL) isolated from mitomycin C-induced Staphylococcus aureus V8 (ATCC 49775). The genome packed in φPVL was a linear double-stranded 40-kb DNA with single-stranded cohesive ends (cos). The [lukS-P V-lukS-PV], attP, and int (integrase gene) of φPVL were all located very close to one another within a 4.0kb-segment on the genome in the order given, and the segment is located at the center from the left and the right cos sites. In addition, the [lukS-P V-lukF-PV]-attP-int region contains 5 direct repeat sequences that show high similarity with the recombinase-binding sites of bacteriophages of S. aureus.

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