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Volume 39, Issue 5
Displaying 1-50 of 60 articles from this issue
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Keiko TANAKA, Tokuji TAKEDA, Koichiro MIYAJIMA1991 Volume 39 Issue 5 Pages 1091-1094
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA mechanism of the cryoprotective effect of saccharides on the denaturation of catalase in the freeze-drying process was studied. Denaturation percents (D%) were measured by changing concentrations of saccharides and catalase. Dependence of D% on a weight ratio of saccharide to catalase suggested that they interact directly with each other. The mode of interaction is probably hydrogen-bonding. An effective number of hydrogen-bonding sites for several saccharides on the surface of the catalase molecule was evaluated by reference to the X-ray analysis data. Glucose, maltose and maltotriose showed a similar protective effect compared on the basis of their weights, and a glucoside group of those saccharides occupied about 5 hydrogen-bonding sites on a catalase molecule at the maximum protection. Saccharides with longer glucoside chains have less protection effect depending on their molecular weights. Judging from the above results, saccharides are bound to catalase as a monomolecualr layer and this layer protects catalase from being denatured instead of the hydration monolayer.View full abstractDownload PDF (705K) -
Hideaki FUJIWARA, Hirofumi YOSHIKAWA, Saburo MURATA, Yoshio SASAKI1991 Volume 39 Issue 5 Pages 1095-1098
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThermodynamic parameters have been measured for alcohol partitioning in the widely used 1-octanol/water system in order to examine thermochemical aspects of partitioning quantitatively. A titration calorimetry is adopted for the experimental procedure, which can afford the partition coefficient and enthalpy (ΔH0p) of partition, and hence the entropy term (ΔS0p) as well, without recourse to the van't Hoff plot after variable temperature experiments. Linear correlations are observed between the observed values of ΔG0p, ΔH0p, and ΔS0p and molar volumes of alcohols. In these correlations, ΔH0p and ΔS0p can clearly discriminate between methyl- and halogen-substituted alcohols whereas ΔG0p cannot. The thermodynamic parameters have also been examined by novel quantitative structure-activity relationship (QSAR) analysis. The enthalpy term ΔH0p is found to afford simple and straightforward correlations with reported biological activities. The origin of this finding is discussed.View full abstractDownload PDF (627K) -
Hideyuki KANNO, Hitoshi YAMAGUCHI, Yoshifumi ICHIKAWA, Sumiro ISODA1991 Volume 39 Issue 5 Pages 1099-1105
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA method for synthesizing 2, 3-(ring fused)-5-(5-tetrazolyl)-4H-pyrimidin-4-one derivative from ethyl 2-(2-tert-butyl-2H-tetrazol-5-yl)-3-(dimethylamino)acrylate (DMTE) (4a) and amino-heterocycles is described. The structure of DMTE, which was prepared from ethyl (2-tert-butyl-2H-tetrazol-5-yl)acetate (3a) with dimethylformamide diethylacetal, was determined by X-ray analysis to be Z form. The reaction of 2-amino-5-methyloxazole (6) with DMTE in acetic acid gave the oxazolo[3, 2-a]pyrimidine derivative (8), heating of which in concentrated sulfuric acid afforded the desired tetrazole derivative (20). Pyrimido[2, 1-b]benzothiazole (21), pyrazolo[1, 5-a]pyrimidine (22 and 23) and [1, 2, 4]triazolo[1, 5-a]pyrimidine (24) derivatives were prepared in a similar manner.View full abstractDownload PDF (843K) -
Masumi TAKEMOTO, Akira KOSHIDA, Keisuke MIYAZIMA, Kunio SUZUKI, Kazuo ...1991 Volume 39 Issue 5 Pages 1106-1111
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn efficient and stereoselective synthesis of optically active clavulones has been accomplished by the use of the unnatural type dichloro Corey lactone 1 as a chiral pool.View full abstractDownload PDF (960K) -
Nobuya KATAGIRI, Makoto MUTO, Masahiro NOMURA, Tohru HIGASHIKAWA, Chik ...1991 Volume 39 Issue 5 Pages 1112-1122
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious carbocyclic ribofuranosyl nucleosides were stereoselectively synthesized through a small number of steps from 2-azabicyclo[2.2.1]hept-5-en-3-ones by the use of sodium borohydride-mediated C-N bond cleavage as a key step. Ready availability of a novel synthetic precursor, (±)-4β-hydroxymethyl-1β-ureidocyclopentane-2α, 3α-diol [(±)-carbocyclic ribofuranosylurea], provides not only facile routes to carbocyclic robofuranosylpyrimidines, but also another route to the corresponding cyclopentylamine, (±)-1β-amino-4β-hydroxymethylcyclopentane-2α, 3α-diol [(±)-carbocyclic ribofuranosylamine], which is useful for the synthesis of the corresponding purine nucleosides.View full abstractDownload PDF (1647K) -
Shigeru OHMIYA, Hajime KUBO, Yuuichi NAKAAZE, Kazuki SAITO, Isamu MURA ...1991 Volume 39 Issue 5 Pages 1123-1125
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new alkaloid (3) was isolated from the stems of Maackia tashiroi (Leguminosae), together with (-)-camoensidine, tashiromine, ammodendrine and six known lupin (quinolizidine) alkaloids. The structure of 3 was characterized as the N15-oxide of (-)-camoensidine, possessing an indolizidine-quinolizidine ring system, by a combination of spectroscopic and chemical methods.View full abstractDownload PDF (565K) -
Kunio HASHIGAKI, Keizo KAN, Nazmul QAIS, Yasuo TAKEUCHI, Masatoshi YAM ...1991 Volume 39 Issue 5 Pages 1126-1131
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel synthetic route to enantiomerically pure 1-benzyltetrahydroisoquinolines (1) was developed via the reaction of oxazolo[2, 3-a]tetrahydroisoquinoline (5) with benzyltriisopropoxytitanium compounds (10). This method was applied to the synthesis of (S)-trimetoquinol (1c; a bronchodilator).View full abstractDownload PDF (913K) -
Yutaka OZAKI, Ikumi OSHIO, Yasue OHSUGA, Shouichi KABURAGI, Zhung-Zhu ...1991 Volume 39 Issue 5 Pages 1132-1136
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1, 2-Benzenediols were synthesized via 1, 1-bis(ethylthio)-3-cyclohexen-2-one derivatives, which were prepared by condensation of 1, 1-bis(ethylthio)-2-propanone with Mannich bases. Regioselective preparation of their monoethers was also achieved.View full abstractDownload PDF (922K) -
Takashi YOSHIDA, Koh-ichi YOKOYAMA, Osamu NAMBA, Takuo OKUDA1991 Volume 39 Issue 5 Pages 1137-1143
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new monomeric hydrolyzable tannin, tirucallin A (7), and two new dimers, tirucallin B (11) and euphorbin F (14), have been isolated, together with six known polyphenols including euphorbin A, from the stems of Euphorbia tirucalli L., and their structures were elucidated by spectral and chemical methods. Euphorbin F (14) possesses dehydrohexahydroxydiphenoyl and valoneoyl groups, and tirucallin A (7) has a dilactonized veloneoyl group. The orientation of the valoneoyl group of euphorbins A and B was revised.View full abstractDownload PDF (883K) -
Ta-Chen LIN, Takashi TANAKA, Gen-ichiro NONAKA, Itsuo NISHIOKA, Tsuong ...1991 Volume 39 Issue 5 Pages 1144-1147
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree novel complex tannins (flavano-ellagitannins), anogeissinin (9) and anogeissuisins A (10) and B (11), have been isolated from the bark of Anogeissus acuminata (ROXB. ex DC.) GUILL. et PERR. var. lanceolata WALL. ex CLARKE (Combretaceae), together with eight known C-glycosidic hydrolyzable tannins. On the basis of spectroscopic and chemical evidence, anogeissinin (9) was shown to have two C-glycosidic ellagitannin (vescalagin) moieties connected to the C-6 and C-8 positions in the (+)-catechin moiety, while anogeissusins A (10) and B (11) have structures in which the dimeric C-glycosidic ellagitannin, castamollinin (8), is attached to the C-8 position of the (+)-catechin and (+)-gallocatechin moieties, respectively.View full abstractDownload PDF (693K) -
Hiroyuki ISHIBASHI, Mami MINO, Manatsu SAKATA, Atsuhiko INADA, Masazum ...1991 Volume 39 Issue 5 Pages 1148-1151
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEthyl 3-chloro-3-(3, 4-dichlorophenylthio)propanoate (8) reacted with electron-rich arenes in the presence of titanium tetrachloride to give the Friedel-Crafts products 10a-13a. Reactions of 8 with 1-trimethylsilylalkynes 14a-d were effected with aluminum chloride to afford the substitution products 15a-d. Some chemical transformations of the products are also described.View full abstractDownload PDF (741K) -
Toshiko WATANABE, Atsushi KOBAYASHI, Michiko NISHIURA, Hiroyuki TAKAHA ...1991 Volume 39 Issue 5 Pages 1152-1156
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new debenzylation method using aluminum chloride in benzene or anisole, which had been developed by us for N-benzyl-2-acyl- and -2-ethoxycarbonylindoles, was applied to benzyl derivatives of other types of indoles and related compounds. Among them, N-benzyl derivatives of fully aromatized indoles, carbazoles and β-carbolines, and some benzamides were debenzylated successfully, whereas those of oxindoles and heterocyclic amides were not. As to the effect of a p-substituent on the benzyl group, it was found that an electron-donating substituent accelerates deprotection, whereas an electron-attracting substituent delays or prevents deprotection.View full abstractDownload PDF (735K) -
Takashi YOSHIDA, Tong CHOU, Muneto MATSUDA, Taeko YASUHARA, Kazufumi Y ...1991 Volume 39 Issue 5 Pages 1157-1162
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new antitumor trimeric hydrolyzable tannins, woodfordin D (5) and oenothein A (13), were isolated from the dried flowers of Woodfordia fruticosa, and their macrocyclic structures, which have a novel constituent unit (woodfordinoyl group) connecting the monomers, have been elucidated on the basis of spectral and chemical evidence, Oenothein A (13) was also isolated from the leaves of Oenothera biennis.View full abstractDownload PDF (831K) -
Miyoji HANAOKA, Won Jea CHO, Shuji YOSHIDA, Chisato MUKAI1991 Volume 39 Issue 5 Pages 1163-1166
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn efficient and biomimetic introduction of an oxy functionality at the C-10 position in the benzo[c]phenanthridine skeleton was developed by regioselective oxygenation with salcomine-oxygen. This biomimetic procedure was successfully applied to a synthesis of 2, 3, 7, 8, 10-pentaoxygenated benzo[c]phenanthridine alkaloids, chelilutine (8) and sanguilutine (18), from the corresponding 2, 3, 7, 8-tetraoxygenated benzo[c]phenanthridines.View full abstractDownload PDF (739K) -
Reduction of Five-Membered α, β-Unsaturated Lactones and Related Compounds with the Ni2+/BH-4 SystemNobuhiro ABE, Fumiko FUJISAKI, Kunihiro SUMOTO, Seiji MIYANO1991 Volume 39 Issue 5 Pages 1167-1170
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reductions of an α, β-unsaturated lactone (5) and lactam (7) with the Ni2+/BH-4 system resulted in the formation of cis-hydrogenated products (8a and 9a) with high stereoselectivity. The cis products (8a and 9a) were easily isomerized to the corresponding trans isomers (8b and 9b, respectively) by refluxing with sodium methoxide in anhydrous methanol. Isotope labeling studies with methyl cinnamate as the substrate indicated that the reduction with this reducing system poceeds stepwise via a carbon-nickel intermediate.View full abstractDownload PDF (645K) -
Isao KITAGAWA, Youichi FUKUDA, Toshio TANIYAMA, Masayuki YOSHIKAWA1991 Volume 39 Issue 5 Pages 1171-1176
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn iridoid alcohol, rehmaglutin A, and two chlorinated iridoids, rehmaglutins B and D, were isolated from the less polar fraction of Chinese Rehmanniae Radix [the dried root of Rehmannia glutinosa LIBOSCH. (Kan-jio in Japanese)], together with rehmaglutin C, rehmaionoside C, jio-cerebroside, and acteoside. The absolute configurations of rehmaglutins A, B, and D were established on the basis of chemical and spectral evidence which included the chemical derivations of rehmaglutins from the known iridoid glycoside catalpol and the application of the bezoate chirality method.View full abstractDownload PDF (989K) -
Motomasa KOBAYASHI, Nam Kyung LEE, Hirotaka SHIBUYA, Takefumi MOMOSE, ...1991 Volume 39 Issue 5 Pages 1177-1184
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive tridecapeptide lactones, named theonellapeptolides Ia (1), Ib (2), Ic (3), Id (4), and Ie (5), were isolated from the Okinawan marine sponge Theonella swinhoei. Following the structure elucidation of theonellapeptolide Id (4), the structures of theonellapeptolides Ia (1), Ib (2), Ic (3), and Ie (5) were determined on the basis of chemical and physicochemical evidence including high performance liquid chromatography and circlar dichroism combined analysis of the amino acid compositions. Theonellapeptolides Ib (2), Ic (3), Id (4), and Ie (5) exhibit moderate cytotoxic activity towards for L1210 in vitro (IC50 1.6, 1.3, 2.4, and 1.4 μg/ml, respectively), and theonellapeptolide Ie (5) exhibits ion-transport activities for Na+ and K+ ions.View full abstractDownload PDF (973K) -
Kazuko YOSHIKAWA, Shigenobu ARIHARA, Jen-Der WANG, Takao NARUI, Toru O ...1991 Volume 39 Issue 5 Pages 1185-1188
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new fibrinolytic saponins, lucyosides N and P, were isolated from the seeds of Luffa cylindrica ROEM. (Cucurbitaceae). On the basis of chemical and spectral evidence, lucyoside N was characterized as 3-O-β-D-galactopyranosyl-(1→2)-β-glucuronopyranosyl-28-O-β-D-xylopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→3)]-α-L-rhamnopyranosyl-(1→2)-α-arabinopyranosyl quillaic acid. Lucyoside P was characterized as a gypsogenin glycoside with the same sugar moiety as lucyoside N.View full abstractDownload PDF (710K) -
Akimori WADA, Syuichi HIRAI, Miyoji HANAOKA1991 Volume 39 Issue 5 Pages 1189-1192
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new route is described for the synthesis of pyrido[4, 3-d]pyrimidin-5(6H)-ones. Treatment of methl 2, 4-dimethoxy-6-methyl-5-pyrimidinecarboxylate with lithium diisopropylamine in tetrahydrofuran at -70°C under nitrogen followed by reaction with diaryl imines afforded cycloaddition products. The cycloadducts were aromatized to the corresponding pyrido[3, 4-d]pyrimidin-5(6H)-ones by treatment with N-bromosuccinimide via a benzylic bromination-dehydrobromination sequence.View full abstractDownload PDF (702K) -
Yukio FUJITA, Yoshiaki YOSHIKUNI, Tomoko SOTOMATSU, Tamiki MORI, Takay ...1991 Volume 39 Issue 5 Pages 1193-1198
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of N-phenyl-Δ8-dihydroabietamide analogs were prepared and tested for hypocholesterolemic activity. The effects of substituents of the phenyl moiety on the activities were quantitatively analyzed by using various substituent parameters. The activities were enhanced by the electron-donating effect of ortho and para substituents and the bulkiness of ortho substituents. A combination of 2, 6-dimethylaniline with resin acids other than Δ8-dihydroabietic acid produced lower activities than N-(2, 6-dimethylphenyl)-Δ8-dihydroabietamide, abietane-type carboxamides being somewhat stronger than pimarane-type carboxamides. The conversion of the carboxamide group to other groups resulted in more or less of a decrease in activity, giving evidence that the carboxamide group is important to hypocholesterolemic activity.View full abstractDownload PDF (829K) -
Norikazu TAMURA, Yoshihiro MATSUSHITA, Toshi IWAMA, Setsuo HARADA, Sho ...1991 Volume 39 Issue 5 Pages 1199-1212
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(S)-2-Amino-3-(2, 5-dihydro-5-oxo-4-isoxazolyl)propanoic acid (TAN-950 A (1)) is a novel amino acid antibiotic which shows a high affinity for glutamate receptors of the central nervous system. To improve the affinity for glutamate receptors, the structure-activity relationships of TAN-950 A derivatives 6a-o, 15a-o were investigated. Optically active TAN-950 A analogs 15a-h were synthesized starting with methyl (S)- and (R)-N-Boc-pyroglutamate (8) via acylation at the C-4 position followed by isoxazolone formation with hydroxylamine and subsequent deprotection reactions. The lactam 16, prepared from (RS)-aminoadipic acid, and dimethyl esters 19 of (R)- and (S)-aspartic acid were converted to (RS)-3-methyl-homo-TAN-950 A (15i) and optically active nor-TAN-950 A derivatives 15j-o, respectively, utilizing a similar sequence of reactions.Most of TAN-950 A derivatives 6a-o, 15a-o showed an affinity for glutamate receptors. The 3-alkyl derivatives 15b, d-g, especially, showed a high affinity for the quisqualate subtype-receptor and had a strong activiting effect on the hippocampal neurons (glutamate agonistic activity). The (R)-enantiomer 15a of TAN-950 A had increased selectivity for the N-methyl-D-aspartate (NMDA) subtype-receptor. This selectivity was further enhanced by removal of the methylene group in the amino acid moiety of 15a. The most potent and selective NMDA agonistic activity was observed with (R)-3-methyl-nor-TAN-950 A (15m).View full abstractDownload PDF (1716K) -
Yusuke SASAKI, Akihiro AMBO, Kenji SUZUKI1991 Volume 39 Issue 5 Pages 1213-1216
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPresumable dermorphin precursor peptide derivatives comprized of 35 amino acids and their fragments, which are based on the amino acid sequence determined by recombinant deoxyribonucleic acid (DNA) techniques, were synthesized by the solid phase method. A 35-residue peptide amide containing L-Ala2-dermorphin sequence at the N-terminus (1) as well as its D-Ala2 isomer (2) and the C-terminal 20-residue peptide amide were found to be unexpectedly stable against aminopeptidase M digestion and in rat brain membrane fractions mixture, suggesting that the C-terminal Glu-rich moiety of 1 and 2 serves to protect from enzymatic breakdown. In the opioid receptor binding assay, 2 showed 40 and 25-fold higher affinities than 1 for μ and δ-receptors, respectively. The N-terminal 15-residue peptide fragment of 2 showed greatly increased affinities for both receptors, being one half of those of dermorphin, whereas that of 1 showed low affinities. Opioid receptor binding properties of these synthetic peptides may be useful in investigation of the processing to dermorphin.View full abstractDownload PDF (612K) -
Chisako YAMAGAMI, Narao TAKAO1991 Volume 39 Issue 5 Pages 1217-1221
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe retention behavior of monosubstituted pyrazines was investigated by comparing the hydrophobic contribution of each substituent (κ) to the capacity factor obtaiend from reversed-phase high-performance liquid chromatography (HPLC), using a C18 capsule-type column and methanol-water eluents of various compositions. The mobile phase dependency of κ showed that the retention mechanism varied with the substituent, especially in mobile phases with very high water content, due to the intervention of the selective solute-solvent interactions. Under such circumstances, the capacity factor (log k') obtaiend from HPLC methods correlated very poorly with the octanol-water partition coefficient (log P). The log k' for pyrazines with only alkyl and/or alkoxy groups was measured and the correlation with log P was examined. An excellent linear correlation was obtained with the eluent containing about 30% methanol. However, at other methanol concentrations, the log k' values of the alkyl and alkoxy derivatives correlated with log P by two separated linear equations. The use of log kW (log k' at 100% water), which has so far been considered to be the best index of hydrophobicity, failed to simulate log P.View full abstractDownload PDF (739K) -
Tomoo AOYAMA, Hiroshi ICHIKAWA1991 Volume 39 Issue 5 Pages 1222-1228
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIntroducing a forgetting process in the learning phase of the neural network resulted in localizing the connections in the weight matrices. Such weight matrices, reconstructed weight matrices, indicated the active neurons in the network and were used to analyze the relationships between the input and output data. The relationship between the adaptive least-squares (ALS) method and the neural network led to the conclusion that the operation of the ALS method is, indeed, a restricted operation of the neural network.View full abstractDownload PDF (983K) -
Mohamed S. KAMEL, Kazuhiro OHTANI, Tomonori KUROKAWA, Mahmoud H. ASSAF ...1991 Volume 39 Issue 5 Pages 1229-1233
Published: 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn aqueous extract of mesocarps of the fruits of Balanites aegyptiaca exhibited a prominent antidiabetic activity by oral administraction in streptozotocin induced diabetic mice. From one of the active fractions of this extract, two new steroidal saponins were isolated, and their structures were determined as 26-O-β-D-glucopyranosyl-(25R)-furost-5-ene-3β, 22, 26-triol 3-O-[α-L-rhamnopyranosyl-(1→2)]-[β-D-xylopyranosyl-(1→3)]-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranoside and its 22-methyl ether. In addition, two known saponins, 26-O-β-D-glucopyranosyl-(25R)-furost-5-ene-3β, 22, 26-triol 3-O-(2, 4-di-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside and its methyl ether were isolated and identified. It was revealed that the individual saponins did not show antidiabetic activity, while the recombination of these saponins resulted in significant activity. From an ethanolic extract of the epicarps, two known flavonol glycosides, isorhamnetin-3-O-robinobioside and isorhamnetin-3-O-rutinoside were isolated and identified.View full abstractDownload PDF (803K) -
Hiroaki TAKAYANAGI, Haruo OGURA, Yaeko KONDA, Mieko URANO, Yoshihiro H ...1991 Volume 39 Issue 5 Pages 1234-1237
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe crystal and molecular structures of hancokinol and hancolupenone from Cynanchum hancokianum have been determined by X-ray analysis. In the case of hancokinol, among four molecules related on a 4-fold rotation axis, hydrogen bondings between the hydroxyl groups of neighboring molecules are observed.View full abstractDownload PDF (548K) -
Tsutomu HATANO, Toshiyuki FUKUDA, Toshio MIYASE, Tadataka NORO, Takuo ...1991 Volume 39 Issue 5 Pages 1238-1243
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new phenolic compounds, glicoricone (3) and licofuranone (4), were isolated from a species of licorice brought from the northwestern region of China, and their structures were assigned.Among the twelve licorice constituents examined for the inhibition of monoamine oxidase (MAO), six compounds, 3, 4, genistein (6), licopyranocoumarin (7), licocoumarone (14) and glycyrrhisoflavone (15), inhibited the enzyme with the IC50 (concentration required for 50% inhibition of the enzyme activity) values of 6.0×10-5-1.4×10<-4> M. Glycyrrhizin (1) also inhibited MAO with the IC50 value of 1.6×10<-4>M.View full abstractDownload PDF (824K) -
Shunsuke TOYOKAWA, Tadahiro TAKEDA, Yukio KATO, Katsumi WAKABAYASHI, Y ...1991 Volume 39 Issue 5 Pages 1244-1249
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe complete amino acid sequence of a new abortifacient protein, karasurin, was determined. Karasurin, which was isolated from fresh root tubers of Trichosanthes kirilowii MAXIMOWICZ var. japonicum KITAMURA (Cucurbitaceae), was a highly basic protein with pI 10.1 and molecular weight of 28000. Intact karasurin was cleaved with cyanogen bromide, lysyl endopeptidase, formic acid and 2-(2'-nitrophenyl-sulfenyl)-3-methyl-3-bromoindolenine (BNPS-skatole), respectively. Cleavages with N-bromosuccinimide (NBS), trypsin and pepsin were performed for the fragments. The resultant peptide fragments were separated by gel filtration chromatography, reversed-phase high performance liquid chromatography (HPLC) or gel filtration HPLC following sequence analyses by automated Edman methods. Karasurin consists of 246 or 247 amino acid residues with a calculated molecular weight of 27144 or 27215 differing only at the C-terminus with the addition of alanyl residue. Two C-terminal sequences were identified as Asn-Asn-Met-OH and Asn-Asn-Met-Ala-OH by sequence analyses and hydrazinolysis, but there was no micro-heterogeniety in other peptides analysed. The sequence of karasurin revealed a considerable similarity to that of trichosanthin and α-trichosanthin, which are known as abortifacient, ribosome-inactivating and anti human immunodeficiency virus (HIV) (the virus causing aquired immunodeficiency syndrome (AIDS)) proteins, with 93% and 98% identity, respectively.View full abstractDownload PDF (858K) -
Xiao-hong ZHOU, Ryoji KASAI, Masayuki YOSHIKAWA, Isao KITAGAWA, Osamu ...1991 Volume 39 Issue 5 Pages 1250-1252
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSaikosaponins, the active principles of Bupleuri Radix, are generally sparingly soluble in water. The solubilizing effect of Ginseng saponins on saikosaponin-b1 (Sb1) which is formed from saikosaponin-a (Sa) by mild acid treatment, was investigated. It was revealed that the significant increase of the water-solubility of Sb1 with Ginseng saponin mixture was due mainly to malonyl-ginsenosides. Some solubilizing effect was also observed with ginsenoside-Ro (Ro). No solubilizing effect was found with the neutral dammarane saponins, while the effects of malonyl-ginsenosides and Ro were remarkably potentiated in the presence of these neutral dammarane saponins. The water-solubility of Sa was also increased in the presence of malonyl-ginsenosides under cooperation with the neutral dammarane saponins.View full abstractDownload PDF (571K) -
Teruhisa HIRAYAMA, Shinji MIURA, Yasuo MORI, Midori UETA, Eri TAGAMI, ...1991 Volume 39 Issue 5 Pages 1253-1257
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHigh-performance liquid chromatographic determination of several 2-alkenals, specially acrolein, crotonaldehyde, 2-pentenal, 2-hexenal, 2-heptenal, 2-octenal and 2-nonenal, were studied using the precolumn derivatization reagent 2, 4-diaminotoluene. After the selective condensation of these 2-alkenals to form fluorescent 7-amino-6-methylquinoline derivatives, separation of these compounds was achieved on a ODS column (150×4 mm i.d.) with a linear gradient system of acetonitrile and 50 mM mono-ammonium phosphate containing 5 mM sodium 1-octanesulfonate (from 20% acetonitrile to 60% acetonitrile in 1 h), and the separated quinoline derivatives were detected with a fluorescence monitor (396 nm for excitation and 485 nm for emission). There autooxidized unsaturated fatty acid methyl esters and five autooxidized edible oils were subsequently assayed for acrolein (C3), crotonaldehyde (C4), 2-pentenal (C5), 2-heptenal (C7), 2-octenal (C8) and 2-nonenal (C9). The peak of 2-hexenal was interfered with the unknown peak derived from oxidized lipids. Their detection limits (S/N=2) were 10, 10, 25, 25, 50, 50 pg for acrolein, crotonaldehyde, 2-pentenal, 2-heptenal, 2-octenal and 2-nonenal, respectively.View full abstractDownload PDF (757K) -
Hisami SHINOHARA, Naohito OHNO, Toshiro YADOMAE1991 Volume 39 Issue 5 Pages 1258-1262
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe buffer extracts (3S) of sclerotia of Sclerotinia sclerotiorum IFO 9395 contained mitogenic substance(s) to murine splenocytes (Shinohara et al. Chem. Pharm. Bull., 38, 2219 (1990)). Although the native 3S was slightly mitogenic, heating of 3S induced significant mitogenic activity. To isolate the mitogen, we separated 3S by ion-exchange and gel filtration chromatographies. The isolated mitogen, named sclerogen, has a molecular mass of 32 kilodaltons (kDa) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and the isoelectric point (pI) of 5.9 by chromatofocusing. Sclerogen was significantly mitogenic in vitro against murine splenocytes after heat denaturation, and also showed the augmentation of the primary mixed lymphocyte reaction (MLR) in vitro. However, sclerogen did not show the activation of an alternative pathway of complement and hemagglutination activity. These results suggest that sclerogen is a unique mitogen which differs from lectins and shows mitogenicity after heat denaturation.View full abstractDownload PDF (858K) -
Yoshie KITAMURA, Yasuro SUGIMOTO, Tomoyo SAMEJIMA, Kyoko HAYASHIDA, Hi ...1991 Volume 39 Issue 5 Pages 1263-1266
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSRoot cultures of Duboisia myoporoides and D. leichhardtii have been established from granular tissues isolated from a culture line of callus. The granular tissues easily differentiated roots which vigorously grew in liquid Murashige-Skoog medium supplemented with indole-3-butyric acid (IBA) (2 mg/l) and gibberellic acid (1 mg/l).These cultured roots produced atropine, scopolamine and nicotine. Furthermore, anabasine and nornicotine were detected in root cultures of D. myoporoides, and apoatropine in D. leichhardtii root cultures. A high concentration (7-10% (w/v)) of sucrose in the medium was effective in improving both root growth and tropane alkaloid production.View full abstractDownload PDF (1235K) -
Hiroko KOZUKA, Takafumi WATANABE, Shuichi HORIE, Junji YAMADA, Tetsuya ...1991 Volume 39 Issue 5 Pages 1267-1271
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe profile of the changes in the peroxisomal fatty acid oxidation activity in rat liver was compared with that in microsomal ω-oxidation under various conditions such as a 2-week administration of phenoxyacetic acid derivatives and perfluorinated compounds, short and long-term administration of clofibrate and bezafibrate, high-fat diet feeding, starvation and diabetes. The results were summarized as follows : 1) when phenoxyacetic acid derivatives and perfluorinated compounds were administered, there was a significant correlation in the increase of the activities between peroxisomal fatty acid oxidation and microsomal ω-oxidation. 2) On the long-term adiministration (79 weeks) of peroxisome proliferators the activities of the enzymes were significantly reduced, but the levels were still higher than the control level in a similar manner. 3) On high-fat diet feeding the patterns of the changes in the activaties of peroxisomal fatty acid oxidation, carnitine acetyltransferase and microsomal ω-oxidation were similar to each other, differing from the changes in the activities of microsomal aminopyrin demethylase and mitochondrial carnitine palmitoyltransferase. 4) Under starved and diabetic conditions, co-induction of peroxisomal fatty acid oxidation and microsomal ω-oxidation was observed. From these results it is suggested that 1) the biosynthesis of these enzymes would be regulated on the gene expression of the nearby domain and 2) peroxisomal fatty acid oxidation and microsomal ω-oxidation were co-operatively regulated in order to achieve fatty acid metabolism smoothly.View full abstractDownload PDF (836K) -
Akira KAMEI, Misao KATO1991 Volume 39 Issue 5 Pages 1272-1276
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo study the contribution of glycation or the Maillard reaction to the spontaneous coloration of human crystalline lens in aging, we determined 1-deoxyfructosyl adduct and the fluorescent material, which are produced in the early stage of glycation, in the proteins of normal and colored human lenses of different ages. The amount of both glycation products in the lens increased significantly in proportion to aging or the advance of lens coloration. The insolubility of lens protein also increased with the advance of glycation. In addition, the present study showed that glucose and glucose-6-phosphate have higher reactivities with human lens protein than fructose and glucose-1-phosphate.This paper demonstrates that the deeper colored or older aged lens contains larger amounts of glycation products, and that glycation between lens protein and various sugars in vivo may be a serious factor in human lens coloration or insolubilization of lens protein.View full abstractDownload PDF (943K) -
Masumi UEDA, Yasuhiko NAKAMURA, Hirokazu MAKITA, Yu IMASATO, Yoshiaki ...1991 Volume 39 Issue 5 Pages 1277-1281
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe characteristics of agglomerated crystals of enoxacin prepared by a spherical crystallization technique with the acetone-ammonia water-dichloromethane solvent system were investigated. Enoxacin forms a sesquihydrate, but has two different pseudopolymorphs, i.e. anhydrate and trihydrate. The crystalline form of the resultant agglomerates could be controlled by selecting the composition ratio of the three solvents and their mixing procedure. In order to obtain the sesquihydrous agglomerates, the mixing of an ammonia water solution of enoxacin with acetone in the first stage was required. When ammonia concentration in ammonia water used as a bridging liquid was higher, agglomerated crystals became smaller in size and less spherical in shape. The average size of agglomerates decreased with an increase in agitation speed and with a decrease in the ammonia water fraction in the solvent system. Primary crystals composing the agglomerates grew larger in size in the solvent system where the crystallization rate was reduced, resulting in less spherical agglomerates. Spherically agglomerated crystals prepared with a low fraction of ammonia water improved their flowability and packability without much delay in their dissolution rate, as compared with the primary crystals.View full abstractDownload PDF (1016K) -
Eiji HAYAKAWA, Kunitoshi FURUYA, Tokuyuki KURODA, Masuo MORIYAMA, Akir ...1991 Volume 39 Issue 5 Pages 1282-1286
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe viscosity of doxorubicin aqueous solution as a function of pH, ionic strenght, and temperature was studied in detail. The viscosity increased in the presence of NaCl and maximum viscosity was observed at pH 5 to 7 in the pH profiles. When NaCl was added to various concentrations of doxorubicin aqueous solution, the viscosity suddenly increased when the NaCl concentration exceeded a certain level. This concentration for critical gel formation was found to be inversely correlated with the logarithmic doxorubicin concentration.The viscosity of doxorubicin aqueous solution was decreased with rising temperature. The analysis of viscosity on temperature-dependence revealed two gel structures at 20 to 30°C. Activation energy of the viscous flow at lower temperatures was about 15 kcal/mol and that at higher temperatures was about 60 kcal/mol.The viscosity of doxorubicin aqueous solution also increased in the presence of various cations or anions. This increase in the viscosity caused by monovalent cations or anions was in almost inverse correlation with the lyotropic series, which showed that those ions having a weaker dehydration ability induce a higher viscosity of doxorubicin aqueous solution and promote gel formation. In the viscosity increase caused by monovalent cations or anions, a mechanism involving hydration and self-association owing to π-π stacking of doxorubicin molecules was strongly suggested.In the case of bivalent or trivalent cations, those cations having a stronger chelation ability caused a larger increase in the viscosity of doxorubicin aqueous solution, which indicated that self-association due to intermolecular chelation could be the mechanism of gel formation.View full abstractDownload PDF (742K) -
Takuya KUKITA, Akemi YAMAGUCHI, Akihiko OKAMOTO, Masami NEMOTO, Hirosh ...1991 Volume 39 Issue 5 Pages 1287-1291
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe interaction between polyethylene containers and bromhexine·HCl solid dosage forms prepared by different methods was studied. It was found that bromhexine·HCl tablets prepared by the wet method (kneading) had more drug remaining than those prepared by the dry method. The sorption of drug to polyethylene was influenced by the kneading solvents used, and the most effective solvent in preventing sorption was methanol, which has high solubility for bromhexine·HCl. A group mixture of bromhexine·HCl with crystalline cellulose was effective inhibiting the sorption of bromhexine to polyethylene. This was explained in terms of the monomolecular dispersion of bromhexine molecules within the network of cellulose molecules in the ground mixture.View full abstractDownload PDF (730K) -
Esterase-like Activity of Human Serum Albumin. VII. Reaction with p-Nitrophenyl 4-Guanidino-benzoateYukihisa KURONO, Makoto MIYAJIMA, Takeshi TSUJI, Taishi YANO, Toshimas ...1991 Volume 39 Issue 5 Pages 1292-1294
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of p-nitrophenyl 4-guanidinobenzoate (NPGB) with human serum albumin (HSA) was examined kinetically at various pH's and 25°C. The Michaelis constant (Ks in M) and the catlystic rate constant (k2 in s-1) were determiend. The ratio of k2 to k0 (hydrolysis rate constant of NPGB in s-1) at pH 7.4 was 75.6, indicating the esterase-like activity of HSA. The effects of the reversible binding of site-specific drugs and the chemical modification by site-specific reagents on the HSA activity indicated that HSA has multiple reactive sites towards NPGB. Results of the reaction in the presence of excess NPGB over HSA also suggested the existence of multiple active sites. The pH-profile for k2 showed inflection points at about pH 6.0 and pH 10.0, suggesting the involvement of groups with pKa's of 6.0 and 10.0 in HSA.View full abstractDownload PDF (533K) -
Tomoyuki KOSHI, Takahiro TORII, Koichi ARAI, Toshiyuki EDANO, Mitsuter ...1991 Volume 39 Issue 5 Pages 1295-1297
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe produced a monoclonal antibody to endothelin (ET)-1, tested cross-reactivities with the related peptides by enzyme immunoassay, and invenstigated the effects of the antibody on ET-1- or ET-2-inducced vasocontriction of rat isolated thoracic aorta. The antibody recognized ET-1, ET-2 and ET-3, and the immunoreactive site proved to be the N-terminal region but not the C-terminal region of ET-1. Moreover, at an approximate molar-equivalent concentration, the antibody absorbed ET-1 and ET-2, and significantly inhibited ET-1- and ET-2-induced vasoconstriction notwithstanding the presence of the endothelin receptor.View full abstractDownload PDF (534K) -
Ryuichi OKUNAKA, Takao HONDA, Maiko KONDO, Yasumitsu TAMURA, Yasuyuki ...1991 Volume 39 Issue 5 Pages 1298-1301
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of homophthalic anhydride (1) and aldehydes in the presence of a strong base was studied. Reaction of 1 and benzaldehyde in the presence of NaH in anhydrous tetrahydrofuran (THF) at low temperature (0°C-room temperature) followed by treatment with diazomethane gave the cycloadduct, trans-4-methoxycarbonyl-3-phenyl-3, 4-dihydrocoumarin, and the reaction at 50°C gave, after similar work-up, the C-4 methylene condensed product, methyl 2-(2-methoxycarbonylphenyl)-3-phenylacrylate, selectively. Treatment of homophthalic anhydride having a terminal aldehyde group in the side chain at the C-4 position with NaH in anhydrous THF at low temperature resulted in intramolecular cycloaddition in fair yield.View full abstractDownload PDF (615K) -
Hirotaka SHIBUYA, Nobutoshi MURAKAMI, Fukiko SHIMADA, Isao KITAGAWA1991 Volume 39 Issue 5 Pages 1302-1304
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSConstant-current electrolysis of geranyl acetate (2) in CH3CN-H2O afforded eight oxidation products (3-10) which were presumed to be formed through initial oxidation of the double bond at C6-C7. Based on the results of electrolysis of 2 in CH3CN-H218O, we have found that the oxygen atom(s) in the products (3-10) is(are) derived from water used as the reaction medium.View full abstractDownload PDF (635K) -
Kiyoshi IKEDA, Kouki KAWAI, Kazuo ACHIWA1991 Volume 39 Issue 5 Pages 1305-1309
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe syntheses of novel penta-O-acetyl-N-glycoloylneuraminyl- and penta-O-acetyl-3-deoxy-D-glycero-D-galacto-2-nonulopyranosonic acid-(α 2→6)-D-glucosamine-4-phosphate analogues of lipid A containing sialic acid in place of 3-deoxy-D-manno-2-octulosonic acid are described. Preliminary examination of the biological activity revealed that two synthetic disaccharides showed mitogenic activities and weak antitumor activities.View full abstractDownload PDF (778K) -
Mizuo MIZUNO, Munekiyo OKA, Toshiyuki TANAKA, Hirobumi YAMAMOTO, Munek ...1991 Volume 39 Issue 5 Pages 1310-1311
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChemical constituents, in particular, aristololactam derivatives of nine Aristolochia species (A. shimadai, A. manshuriensis, A. cucurbitifolia, A. westlandii, A onoei, A. kaempferi, A. liukiuensis, A. debilis and A. tagara) were analyzed by means of high performance liquid chromatography. The results chemotaxonomically suggested their subgenera, and sometimeas their sections are restricted by the relative content of aristololactam derivatives.View full abstractDownload PDF (375K) -
Toshiyuki KAJI, Tomohiro HAYASHI, Miezi NSIMBA, Kayoko KAGA, Naoko EJI ...1991 Volume 39 Issue 5 Pages 1312-1314
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe investigated the effect of a hot water extract from Gardenia fruit (Gardenia jasminoides ELLIS) (GFE), which has a stimulatory effect on endothelial cell proliferation, on the proliferation of A10 cells, an established cell line of vascular smooth muscle cell from murine aorta in a culture system. GFE did not change the number of A10 cells after a 48 h culture. GFE significantly increased the incorporation of [3H]thymidine and [14C]leucine into the acid-soluble fraction of bovine aortic endothelial cell layers, but significantly decreased that of A10 cells. These results suggested that GFE stimulates the proliferation of endothelial cells but not of A10 cells. In the endothelial cell culture, GFE significantly increased the accumulation of basic fibroblast growth factor, which is an autocrine for endothelial cell proliferation in medium and low-affinity (glycosaminoglycans-binding) fractions, while A10 cells did not produce a significant amount of the factor. Since it is postulated that a selective stimulation of endothelial cell proliferation by increasing the production of basic fibroblast growth factor is appropriate for prevention of arteriosclerosis and thrombosis, GFE may contain a beneficial component as a useful drug.View full abstractDownload PDF (515K) -
Ikuo KUSHIDA, Ayumi TANAKA, Yoshinori KIDANI, Junzo HIROSE, Tadao SAKA ...1991 Volume 39 Issue 5 Pages 1315-1316
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to determine a micro amount of cis- and trans-platin (cis- and trans-diamminedichloroplatinum(II)) separately, we have utilized the trans effect of SCN-.cis-Platin reacted with potassium thiocyanate to give anionic [Pt(SCN)4]2- which was extracted into nitroethane as an ion pair with zephiramine. On the other hand, trans-platin gave neutral trans-[Pt(SCN)2(NH3)2] under the same conditions, which was not extracted into nitroethane. Therefore, it is possible to determine cis- and trans-platin, separately, by the solvent extraction method. In the determination of the mixture of cis- and trans-platin (4.00×10-6 and 2.67×10-6M, respectively), the recovery of each platinum complex was 94±4 and 101±10% for cis- and trans-platin, respectively.View full abstractDownload PDF (452K) -
Kazumi SASAMOTO, Riko ZENKO, Keihei UENO, Yousuke OHKURA1991 Volume 39 Issue 5 Pages 1317-1319
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe chemiluminescence assay of urinary N-acetyl-β-D-glucosaminidase using o-aminophthalylhydrazido-N-acetyl-β-D-glucosaminide as the substrate was examined. Under optimized conditions, a linear chemiluminescence response to the standard N-acetyl-β-D-glucosaminidase (NAGase) of different concentrations was observed with a correlation coefficient of 0.999 over the range of 0.3 to 20 I.U./l. The present method was compared with the prevalent method using p-nitrophenyl-N-acetyl-β-D-glucosaminide in the assay of 20 urine samples from healthy subjects, and the correlation coefficient of 0.891 was obtaiend.View full abstractDownload PDF (514K) -
Takafumi WATANABE, Hiroki ITOGA, Sumito OKAWA, Hiroshi TAMURA, Tetsuya ...1991 Volume 39 Issue 5 Pages 1320-1322
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe in vivo effect of nicardipine, a well-known calcium antagonist, on microsomal ω-oxidation of laurate in clofibrate-treated rat liver was studied. The 15.3-fold induction of the activity by 2 weeks administration of 0.25% clofibrate in the diet was markedly suppressed to about 6-fold by co-administration of nicardipine at 100mg/kg body weight. Similarly, the induction of peroxisomal β-oxidation and carnitine acetyltransferase activities were also suppressed by this simultaneous administration by more than 50%. Although clofibrate also induced the activity of reduced nicotineamide adenine dinucleotide phosphate (NADPH)-cytochrome c reductase and increased the hepatic content of cytochrome P-450, no suppressive effect of nicardipine was observed. Contarily, nicardipine induced the reductase activity and increased the hepatic content of cytochromes P-450 and b5. These results provide the first demonstration of a calcium antagonist, e.g. nicardipine acting as inhibitor of the induction of microsomal ω-oxidation, in association with the inhibition of peroxisome proliferation in animals. The suppression of drug-induced peroxisome proliferation and microsomal ω-oxidation by the calcium antagonist may help in elucidating the causal relationship of the induction mechanisms between peroxisomal and microsomal enzymes.View full abstractDownload PDF (541K) -
Masaya IWAMOTO, Keijiro UCHINO, Toshikatsu TOUKAIRIN, Kiyomi KAWAGUCHI ...1991 Volume 39 Issue 5 Pages 1323-1324
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew 5'-nucleotidase inhibitors named NF-86I, NF86II were recently isolated from the seeds of Areca catechu L. NF-86I and NF86II showed inhibitory effects on the growth of Streptococcus mutans MT8148(c) and Streptococcus mutans MT6715(g), respectively. In addition, these inhibitors could inhibit insoluble glucan formation from sucrose. NF-86I and NF-86II were found to be polyphenolic substances. Some polyphenols such as tannic acid bind non-specifically to proteins (tannic activity). The 5'-nucleotidase inhibitors that we isolated did not show any such activity. However, the growth inhibitory activity and the inhibitory effect on water-insoluble glucan production were equal to tannic acid. It is therefore considered that these inhibitors bind specifically to the bacterial cell surface. Our findings suggest that the 5'-nucleotidase inhibitors NF-86I and NF-86II may be useful anti-plaque preventing agents.View full abstractDownload PDF (493K) -
Yuki SAKAI-TOMITA, Yuki MITANI, Masaaki TSUDA, Tomofusa TSUCHIYA1991 Volume 39 Issue 5 Pages 1325-1327
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn antibiotic formycin A inhibited growth of Vibrio parahaemolyticus under certain conditions, which suggested that formycin A was taken up by cells under these conditions. We found that formycin A was transported via the adenosine transport system which we previously reported as a Na+-coupled contransport system. We isolated many formycin A resistant mutants, and about half of them grew very poorly on adenosine as a sole source of carbon. Judging from their reversion frequencies, these mutants seemed to have single mutations. Respiration driven uptake of 14C-adenosine was not observed in such mutants; also, Na+ uptake induced by the addition of adenosine or formycin A to a cell suspension was completely abolished in them. Thus we conclude that these mutants possess a defect in the Na+/adenosine cotransport system, and have become formycin A resistant.View full abstractDownload PDF (587K) -
Susumu KIMURA, Teruko IMAI, Masaki OTAGIRI1991 Volume 39 Issue 5 Pages 1328-1329
Published: May 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe dissolution behavior of ibuprofen from a kneaded mixture with low-molecular gelatin (LM gelatin) has been studied in comparison to kneaded mixtures prepared with other additives. Their in vivo absorption behaviors were also examined. The LM gelatin markedly enhanced the dissolution rate of ibuprofen compared to that with polyethylene glycol (PEG) 6000, dextran T10 or pullulan. Oral administrations of the kneaded mixture to beagle dogs showed the LM gelatin to be most effective in accelerating the absorption rate of ibuprofen among the additives used.View full abstractDownload PDF (415K)