Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 65, Issue 6
Displaying 1-30 of 30 articles from this issue
Analytical Chemistry
Organic Chemistry
  • Gyo-Cheol GOO, Sang-Tai CHOI, Hyung-Geun AHN, Kyung-Sik SONG
    2001 Volume 65 Issue 6 Pages 1296-1301
    Published: 2001
    Released on J-STAGE: July 31, 2002
    JOURNAL FREE ACCESS
    The underground portion of the Welsh onion (Allium fistulosum) was extracted and separated into seven fractions to purify allelopathic compounds that were found to promote the growth of rice seedlings (Oryza sativa). The 80% (v/v) ethanol-insoluble fraction of the hot water extract showed the highest growth-promoting effect. Purification by DEAE-cellulose chromatography gave four fractions, AD-1, 2, 3 and 4. AD-3 at 1000 ppm stimulated root and shoot growth by about 2.4 and 1.5 times over the respective water and sucrose-treated controls. The molecular weight of AD-3 was roughly estimated as 630 kDa by gel permeation chromatography. Seventy two percent (by wt.) of AD-3 was a carbohydrate and no proteins were detected. A GC analysis of the neutral sugar composition revealed the presence of Gal (50.1%), Man (17.9%), Ara (10.4%), Rha (8.8%), Glc (7.2%) and Xyl (5.6%). About 3% (by wt.) of the total carbohydrate was uronic acid, which was identified as GalU by a GC analysis. The remainder of AD-3 was extracted in ethyl acetate after its hydrolysis with 2 M HCl. The major component of the ethyl acetate-soluble fraction was identified as unsaturated linear primary alcohols, 1-tetradecanol and 1-octadecanol (16% and 84% by peak areas from GC, respectively) by means of NMR and GC-MS. Sole or combined treatment of these alcohols did not affect the growth of rice seedlings. After partial hydrolysis with 0.2 M trifluoroacetic acid or by a sodium periodate treatment, the activity of AD-3 had completely disappeared, suggesting that the sugar moiety and/or molecular size were important for the activity.
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  • Toshiya MASUDA, Kumiko IRITANI, Shigetomo YONEMORI, Yasuo OYAMA, Yoshi ...
    2001 Volume 65 Issue 6 Pages 1302-1309
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Four kinds of galloyl flavonol glycosides were found in the leaf extract of Pemphis acidula, a plant growing on the subtropical seashore. Their chemical structures were elucidated to be quercetin or kaempferol 6''-O-galloyl-β-D-glycosides by using spectroscopic and chemical analyses. One of the flavonols, kaempferol-3-O-(6-O-gallyol-β-D-galactopyranoside), was newly isolated from natural sources and its structure was completely determined in this investigation. The antioxidant-related activities of the galloyl flavonoids were examined by the DPPH antiradical activity, inhibition of methyl linoleate oxidation, and inhibition of oxidative cell death. These results were compared with those of the corresponding non-galloylated flavonol glycosides and their aglycones. The galloyl flavonoids showed more efficient activity than that of the corresponding flavonol glycosides, but not more than that of the corresponding aglycones in the three assays applied.
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  • Yuko NAKAHARA, Sumie ANDO, Yukishige ITO, Hironobu HOJO, Yoshiaki NAKA ...
    2001 Volume 65 Issue 6 Pages 1358-1368
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    The prototype glycopeptidyl fragments of serglycin, a proteoglycan with the characteristic peptide sequence of repeating L-seryl-L-glycine, were synthesized by a convergent method involving block condensation on a solid support. In order to facilitate detachment of the protected glycopeptides from the resin, a new allyl ester type of linker, which is cleavable by Pd(0)-catalysis, was designed and used in combination with the commercial acid-labile Sieber amide resin for the solid-phase synthesis. Glycopeptide blocks consisting of [O-(2,3,4-tri-O-acetyl-D-xylosyl)-L-seryl-L-glycine]n (n=1-8) were produced in good yields. Block condensation in a solution was also successful to synthesize up to the hexadecapeptide (n=8).
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  • Yoshifusa TAKEUCHI, Qian CHENG, Qing-Wen SHI, Takeyoshi SUGIYAMA, Taka ...
    2001 Volume 65 Issue 6 Pages 1395-1398
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Two novel polyoxygenated cyclohexenes, 6-methoxyzeylenol (3) and 2-acetoxyzeylenone (4), together with two known compounds, zeylenol (1) and zeylenone (2), were isolated from the heartwood of the Chinese tree, Uvaria purpurea. Zeylenol (1) and zeylenone (2) both showed inhibitory activity toward the root growth of Lactuca sativa. Their structures were established by spectroscopic and chemical methods.
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  • Ken FUJITA, Kenji MORI
    2001 Volume 65 Issue 6 Pages 1429-1433
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Serricornin [(4S,6S,7S)-7-hydroxy-4,6-dimethyl-3-nonanone], the female sex pheromone of Lasioderma serricorne, was synthesized by starting from (2S,4S)-2,4-dimethyl-1,5-pentanediol that had been obtained by lipase-catalyzed enantiomer separation of its racemate.
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  • Xiao Hui CHEN, Chul-Sa KIM, Takehiro KASHIWAGI, Shin-ichi TEBAYASHI, M ...
    2001 Volume 65 Issue 6 Pages 1434-1437
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    The hexane-soluble fr. was found to be as intense in antifeeding activity as the crude methnol extract of Cryptomeria japonica against Acusta despesta. This hexane soluble-fraction was used to isolate and identify two sesquiterpenols, (−)-cubebol and (+)-2,7(14),10-bisabolatrien-1-ol-4-one, as the active compounds. Both compounds strongly inhibited the feeding behavior of A. despesta at 120 μg/cm2 and 80 μg/cm2 concentrations, respectively.
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Biochemistry & Molecular Biology
  • Takuma KIMURA, Takeshi NAKANO, Noriyuki TAKI, Mayuko ISHIKAWA, Tadao A ...
    2001 Volume 65 Issue 6 Pages 1275-1283
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    The cell growth and plastid development of cultured green tobacco cells were maintained by the phytohormone cytokinin. After subculture into cytokinin-free medium, when cytokinin treatment was resumed, physiological changes induced by cytokinin were analyzed. Changes in chlorophyll biosynthesis and photosynthetic gene expression were observed 1 week after cytokinin induction, and changes in cell growth were observed 2 weeks after cytokinin induction. Two cytokinin-induced genes (cig) were isolated from these cells using the fluorescent differential display technique. Northern analysis confirmed that expression of these cig was induced by both natural and synthetic cytokinins. The expression of cig1 was also induced by abscisic acid, and its cDNA sequence was similar to the proline dehydrogenase gene. The expression of cig2 is specific to cytokinin and is not induced by other phytohormones. The amino acid sequence encoded by cig2 is similar to the GDP/GTP exchange factor eIF2B, which regulates translation initiation. The expression of these cig suggests a complex induction system involving cytokinin and other phytohormones.
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  • Kun NA, Hoo-Kyun CHOI, Toshihiro AKAIKE, Keun-Hong PARK
    2001 Volume 65 Issue 6 Pages 1284-1289
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Copolymers composed of an Arg-Gly-Asp (RGD) sequence for the adhesion molecule and sugar moieties were synthesized for an insulinoma cell (MIN6) culture. MIN6 cells attached on the poly(N-p-vinylbenzyl-D-maltonamide-co-6-(p-vinylbenzamido)-hexanoic acid-g-GRGDS) (p(VMA-co-VBGRGDS))-coated dishes were in a more aggregated form than other polymer-coated surfaces. P(VMA-co-VBGRGDS) also shows faster proliferation of MIN6 cells (about 18% higher) than with p(VLA-co-VBGRGDS). By interaction between cell and matrix, about 80% greater insulin secretion from MIN6 cells was produced with the p(VMA-co-VBGRGDS), and about 50% greater insulin secretion was produced with the poly(N-p-vinylbenzyl-D-lactonamide-co-6-(p-vinylbenzamido)-hexanoic acid-g-GRGDS) (p(VLA-co-VBGRGDS) as compared with unstimulated cells. Moreover, attachment of MIN6 cells treated with RGD monomer was suppressed approximately 50% for the p(VMA-co-VBGRGDS) surface. This result supported the idea that conjugation of adhesion molecules of RGD peptide in p(VMA-co-VBGRGDS) copolymer specifically interact with integrin families on MIN6 cell membrane.
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  • Kanako SUZUKI, Tomio YABE, Yutaka MARUYAMA, Keietsu ABE, Tasuku NAKAJI ...
    2001 Volume 65 Issue 6 Pages 1310-1314
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Yeast exo-β-1,3-glucanse gene (EXG1) was expressed in Escherichia coli and the recombinant enzyme (EXg1p) was characterized. The recombinant Exg1p had an apparent molecular mass of 45 kDa by SDS-PAGE and the enzyme has a broad specificity for β-1,3-link-ages as well as β-1,6-linkages, and also for other β-glucosidic linked substrates, such as cellobiose and pNPG. Kinetic analyses indicate that the enzyme prefers small substrates such as laminaribiose, gentiobiose, and pNPG rather than polysaccharide substrates, such as laminaran or pustulan. With a high concentration of laminaribiose, the enzyme catalyzed transglucosidation forming laminarioligosaccharides. The enzyme was strongly inhibited with high concentrations of laminaran.
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  • Tsutomu ARAKAWA, John S. PHILO, Yoshiko KITA
    2001 Volume 65 Issue 6 Pages 1321-1327
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Thermal stress was used to assess the stability of recombinant human erythropoietin (EPO) derived from Chinese hamster ovary cells. In 20 mM phosphate at pH 7.0, this protein had a highly reversible thermal unfolding as observed by far UV circular dichroism (CD) and native gel analysis, with no indication of protein aggregation. It had a relatively low melting temperature at 53°C. Assuming a two-state transition, the observed reversibility permits thermodynamic analysis of the unfolding of EPO, which shows that the free energy of unfolding at 25°C is only 6-7 kcal/mol. Upon heating to 79°C over 30 min, however, this protein does undergo aggregation as assessed by native gel. In 20 mM phosphate and citrate at pH 7.0, the results are similar, i.e., EPO suffered a substantial aggregation, while it showed little aggregation in 20 mM Tris or histidine at pH 7.0 and 20 mM glycine at pH 6.3 under identical heat treatment.
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  • Hiroaki TATENO, Tomohisa OGAWA, Koji MURAMOTO, Hisao KAMIYA, Toshiaki ...
    2001 Volume 65 Issue 6 Pages 1328-1338
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    An L-rhamnose-binding isolectin named STL3 (subunit Mr, 21.5 k) was isolated from eggs of the steelhead trout (Oncorhynchus mykiss) in addition to STL1 (subunit Mr, 31.4 k) and STL2 (subunit Mr, 21.3 k) that had been already isolated. STLs were composed of non-covalently linked subunits. The primary structures of STL1 and STL3 were analyzed by the combined use of protein sequencing and cDNA sequencing. A cDNA encoding STL2, of which the protein sequence had been previously studied, was also analyzed. The STL1 subunit (289 amino acid residues) had different structural properties compared to those of the STL2 subunit (195 amino acid residues) and the STL3 subunit (195 amino acid residues); e.g., the number of repeated domain (three for STL1, and two for STL2 and STL3), although all of them were composed of tandemly repeated homologous domains (40 to 53% identities). The lectin levels in various tissues and during the embryonic development showed that STL1 had different distribution and expression profiles from those of STL2 and STL3. Although STL1 could be detected in several tissues and serum of both male and female steelhead trout, STL2 and STL3 were only abundant in the ovary. STL2 and STL3 levels dramatically decreased just after hatching, however, the STL1 level increased temporarily. These results indicate that the multiple lectins from eggs of the steelhead trout form a novel rhamnose-binding lectin family with different structures and tissue distribution to share distinct functions in eggs.
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  • Imre SALLAY, Sumiki TOJO, Koji NOMIYAMA, Yoshiaki KOUZUMA, Makoto KIMU ...
    2001 Volume 65 Issue 6 Pages 1347-1352
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    CEL-III, a galactose/N-acetylgalactosamine (Gal/GalNAc)-specific lectin purified from a marine invertebrate, Cucumaria echinata, has a strong hemolytic activity, especially toward human and rabbit erythrocytes in the presence of Ca2+. We evaluated the role of Ca2+ in hemagglutinating and hemolytic activities of CEL-III. We found that Ca2+ is closely associated with both activities of CEL-III. The fluorescence spectra of CEL-III upon binding to Ca2+ were measured. The result showed a structural change of CEL-III in the presence of Ca2+. The structural change of CEL-III upon Ca2+ binding was further demonstrated by stabilization against urea denaturation and by insusceptibility to protease digestions. CEL-III was completely unfolded at a low concentration of 2 M urea, while CEL-III complexed with Ca2+ was stable in 6 M urea. As for protease digestions, CEL-III monomer and oligomer were readily digested by trypsin, chymotrypsin, and papain in the absence of Ca2+, while they were insusceptible to the three proteases in the presence of Ca2+. The papain digestion of the decalcified oligomer produced a large C-terminal peptide, suggestting that the C-terminal region of CEL-III may participate in oligomerization of CEL-III as a core domain.
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  • Machiko NAKAMURA, Natsuko KUROIWA, Yoshiki KONO, Akira TAKATSUKI
    2001 Volume 65 Issue 6 Pages 1369-1378
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    PDMP (D,L-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol) and PPMP (D,L-threo-1-phenyl-2-hexadecanoylamino-3-morpholino-1-propanol), inhibitors of glucosylceramide synthesis, blocked brefeldin A (BFA)- and nordihydroguaiaretic acid-induced dispersal of the Golgi and trans Golgi network, and Golgi-derived vesicles were retained in the juxtanuclear region. PDMP and PPMP did not stabilize microtubules but blocked nocodazole-induced extensive fragmentation and dispersal of the Golgi, and large Golgi vesicles were retained in the juxtanuclear region. PPMP is a stronger inhibitor of glucosylceramide synthesis than PDMP, but PDMP showed a stronger activity against BFA-induced retrograde membrane flow. However, PPMP showed a stronger activity for Golgi disruption and inhibition of anterograde trafficking from the endoplasmic reticulum, and rebuilding of the Golgi architecture. Cumulatively, these results suggest that sphingolipid metabolism is implicated in maintenance of the Golgi architecture and anterograde membrane flow from the endoplasmic reticulum but not in Golgi dispersal induced by BFA.
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  • Masao TOKUNAGA, Yoichi SHIRAISHI, Masatake ODACHI, Makoto MIZUKAMI, Hi ...
    2001 Volume 65 Issue 6 Pages 1379-1387
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    The groESL locus of a protein-hypersecreting bacterium, Bacillus brevis, was cloned by PCR using primers designed based on the DNA sequence of a B. subtilis homolog. GroEL protein was purified to apparent homogeneity and its ATPase activity was characterized: it hydrolyzed ATP, CTP, and TTP in this order of reaction rate, and its specific activity for ATP was 0.1 μmole/min/mg protein. Purified GroEL forms a tetradecamer. GroEL was estimated to contain 22% α-helix, 24% β-sheet, and 19% turn structures, by CD measurement. GroES protein was also highly purified to examine its chaperonin activity. GroEL protected from thermal inactivation of and showed refolding-promoting activity for malate dehydrogenase, strictly depending on the presence of ATP and GroES.
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  • Nobuyuki KOBASHI, Makoto NISHIYAMA, Hisakazu YAMANE
    2001 Volume 65 Issue 6 Pages 1391-1394
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    A search in the Bacillus subtilis genome sequence found that the gene designated yclM encode(s) a protein showing significant identity in amino acid sequence to aspartate kinases. When yclM was introduced into Escherichia coli cells deficient in all three aspartate kinase genes, production of a protein with molecular size 50 kDa, which was similar to the value deduced from the nucleotide sequence of the gene, was observed. Expectedly, the protein purified to homogeneity had aspartate kinase activity. The enzyme was significantly inhibited by simultaneous addition of both threonine and lysine, which is a typical feature of aspartate kinase III of B. subtilis. The enzyme was very unstable in 10 mM tris-HCl (pH 7.5) buffer, but was stabilized by addition of 500 mM ammonium sulfate. Although all the aspartate kinases so far investigated are oligomeric enzymes, this aspartate kinase was suggested to be a monomer.
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  • Rashmi SHARMA, Arun SHARMA, Tetsuya SHONO, Mitsuo TAKASUGI, Akira SHIR ...
    2001 Volume 65 Issue 6 Pages 1402-1405
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Mulberry leaves treated with UV-C were found to accumulate three different phytoalexins, moracin C, moracin N, and chalcomoracin. The increased level of malondialdehyde in UV-treated leaves along with moracins suggested their role as a free-radical scavenger in stressed plants. All the three moracins induced under UV stress were capable of scavenging the superoxide anion generated by the xanthine-xanthine oxidase system. Also, moracins were capable of inhibiting lipid peroxidation, which strongly indicates their role as a scavenger.
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  • Joong-Hoon AHN, Paola SPOSATO, Su-Il KIM, Jonathan D. WALTON
    2001 Volume 65 Issue 6 Pages 1406-1411
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    A new cellulase gene, cel2, from the filamentous fungus Cochliobolus carbonum was cloned by using egl-1 of Trichoderma reesei as a heterologous probe. DNA blot analysis of cel2 showed that this gene is present as a single copy. The gene contains one 49-bp- intron. cel2 encodes a predicted protein (Cel2p) of 423 amino acids with a molecular mass of 45.8 kDa. The predicted pI is 4.96. It shows similarity to other endoglucanases from various fungi. From the comparison with other cellulase genes, cel2 belongs to family 7 of glucohydrolases. cel2 is located on a 2.5-Mb chromosome in C. carbonum and its expression is repressed by sucrose. A cel2 mutant of C. carbonum was created by transformation-mediated gene disruption. The pathogenicity of the mutant was indistinguishable from the wild type, indicating that cel2 by itself is not important for pathogenicity.
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  • Masayuki KITA, Akira KOMATSU, Mitsuo OMURA, Masamichi YANO, Yoshinori ...
    2001 Volume 65 Issue 6 Pages 1424-1428
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    A cDNA clone encoding phytoene desaturase (PDS) was isolated from citrus (Citrus unshiu Marc.). The transcript of the isolated PDS (CitPDS1) was not detected by conventional RNA gel-blot analysis; instead, it was detected by a sensitive reverse transcription-PCR (RT-PCR). The CitPDS1 transcript in the juice sacs/segment epidermis (edible part) was at a low level in the young fruit, and it increased toward maturation like citrus phytoene synthase (CitPSY1). In the peel, in contrast to CitPSY1, the transcript of which was induced toward maturation, the level of the CitPDS1 transcript remained constant after an increase in July, indicating non-coordinate regulation of CitPDS1 and CitPSY1 in the peel.
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Food & Nutrition Science
  • Katsumi SHIBATA, Tsutomu FUKUWATARI, Etsuro SUGIMOTO
    2001 Volume 65 Issue 6 Pages 1339-1346
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    The effects of pyrazinamide on the metabolism of tryptophan to niacin and of tryptophan to serotonin were investigated to elucidate the mechanism for pyrazinamide action against tuberculosis. Weanling rats were fed with a diet with or without 0.25% pyrazinamide for 61 days. Urine samples were periodically collected for measuring the tryptophan metabolites. The administration of pyrazinamide significantly increased the metabolites, 3-hydroxyanthranilic acid and beyond, especially quinolinic acid, nicotinamide, N1-methylnicotinamide, and N1-methyl-4-pyridone-3-carboxamide, and therefore significantly increased the conversion ratio of tryptophan to niacin and the blood NAD level. However, no difference in the upper metabolites of the tryptophan to niacin pathway such as anthranilic acid, kynurenic acid and xanthurenic acid was apparent between the two groups. No difference in the concentrations of trytptophan and serotonin in the blood were apparent either. It is suggested from these results that the action of pyrazinamide against tuberculosis is linked to the increase in turnover of NAD and to the increased content of NAD in the host cells.
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  • Yasuhiro TOBA, Yukihiro TAKADA, Yasuhiro MATSUOKA, Yoshikazu MORITA, M ...
    2001 Volume 65 Issue 6 Pages 1353-1357
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Milk contains several components effective for bone health. In the previous in vitro and in vivo studies, we have shown that milk whey protein, especially its basic protein fraction (milk basic protein [MBP]), promoted bone formation and suppressed bone resorption. This present study examines the effect of MBP on the biochemical markers of bone metabolism in healthy adult men. Experimental beverages containing MBP (300 mg of MBP a day) were given to 30 normal healthy adult men for 16 days. The serum osteocalcin concentration had increased significantly after 16 days of ingesting the experimental beverage containing MBP. Urinary cross-linked N-teleopeptides of type-I collagen (NTx) excretion had decreased significantly after 16 days of ingesting MBP. The urinary NTx excretion was related to the serum osteocalcin concentration after 16 days of ingestion. These results suggest that MBP promoted bone formation and suppressed bone resorption, while maintaining the balance of bone remodeling.
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  • Hiroyuki TOMOTAKE, Iwao SHIMAOKA, Jun KAYASHITA, Fumiyo YOKOYAMA, Misa ...
    2001 Volume 65 Issue 6 Pages 1412-1414
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    We investigated the effects of a buckwheat protein product (BWP), soy protein isolate (SPI) and casein on the plasma cholesterol level and fecal steroid excretion in rats fed on a cholesterol-free diet. The consumption of BWP suppressed plasma cholesterol by enhancing the fecal excretion of both neutral and acidic steroids. These effects of BWP were stronger than those of SPI.
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  • Katsumi SHIBATA, Tsutomu FUKUWATARI, Satomi ZUSHI, Etsuro SUGIMOTO
    2001 Volume 65 Issue 6 Pages 1415-1418
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Hairless mice were fed with a 10% amino acid mixture diet (control diet, 0.42% histidine content), the control diet without histidine (histidine-free diet), or the control diet rich in histidine (histidine-rich diet; histidine content, 4.2%) for 32 days. They were irradiated with UV light of 312 nm for 30 min, and skin samples were periodically taken for measuring the urocanic acid isomers. Total urocanic acid isomers were decreased by UV irradiation in all the three groups, the recovery being the fastest in the histidine-rich group. The percentage increase in cis-urocanic acid/total urocanic acid was quickly increased by UVB irradiation. The recovery of the ratio was slightly higher in the histidine-rich group, although the total urocanic acid level was higher in the histidine-rich group than in the others. Therefore, the absolute cis-urocanic acid content in the skin was almost the same among the three groups. These results indicate that the increased histidine intake strengthened UVB protection without any decrease in immune suppression.
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  • Junko HIROSE, Setsuko ITO, Noriko HIRATA, Shoko KIDO, Naofumi KITABATA ...
    2001 Volume 65 Issue 6 Pages 1438-1440
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    The major food allergen, ovomucoid (molecular weight of 28 kDa) could be detected in 12 of 37 human breast milk samples by using three types of enzymelinked immunosorbent assay. By gel-filtration, ovomucoid in breast milk was only eluted in the fractions corresponding to a molecular weight of about 450 kDa, suggesting its occurrence as an immune complex with IgA. In fact, almost the same elution profile as that for ovomucoid was obtained for its immune complex with IgA by gel-filtration.
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  • Kaeko MUROTA, Noriko MATSUI, Teruo KAWADA, Nobuyuki TAKAHASHI, Tohru F ...
    2001 Volume 65 Issue 6 Pages 1441-1443
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    We investigated the influence of glycerol esters on oleic acid uptake into IEC-6 cells. Monoolein, especially 2-monoacylglycerol, significantly inhibited the cellular uptake. Although diolein slightly inhibited the oleic acid uptake, triolein, glycerol and monooctanoate had no effect. These results suggest that after lipid digestion in the intestine, long-chain fatty acid uptake may be influenced by another digestive product, 2-monoacylglycerol.
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  • Mitsuru YOSHIDA, Hiroshi ONO, Yoshiko MORI, Yoshihiro CHUDA, Koichi ON ...
    2001 Volume 65 Issue 6 Pages 1444-1446
    Published: 2001
    Released on J-STAGE: July 31, 2002
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    Bisphenol A was oxidized to monoquinone and bisquinone derivatives by Fremy’s salt, a radical oxidant, though salcomine and alkali did not catalyze the oxidation by molecular oxygen. Bisphenol A, bisphenol B, and 3,4'-(1-methylethylidene)bisphenol were converted to their monoquinone derivatives in the presence of tyrosinase at 25°C at pH 6.5, but not to the bisquinone derivatives under these conditions.
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Microbiology & Fermentation Technology
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