Showing papers by "Mitsuo Miyazawa published in 2003"

Antimutagenic Activity of Flavonoids from Chrysanthemum morifolium

Abstract: A methanol extract from the flower heads of Chrysanthemum morifolium showed a suppressive effect on umu gene expression of the SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide). The methanol extract was re-extracted with hexane, chloroform, ethyl acetate, butanol, and water. The ethyl acetate fraction showed a suppressive effect. Suppressive compounds in the ethyl acetate fraction were isolated by silica gel column chromatography and identified as the flavonoids acacetin (1), apigenin (2), luteolin (3), and quercetin (4) by EI-MS, IR, and (1)H and 13C NMR spectroscopy. Compounds 1-4 suppressed the furylfuramide-induced SOS response in the umu test. Compounds 1-4 suppressed 60.2, 75.7, 90.0, and 66.6% of the SOS-inducing activity at a concentration of 0.70 micromol/ml. The ID50 (50% inhibitory dose) values of 1-4 were 0.62, 0.55, 0.44, and 0.59 micromol/ml. These compounds had the suppressive effects on umu gene expression of the SOS response against other mutagens, 4-nitroquinolin 1-oxide (4NQO) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), which do not require liver-metabolizing enzymes. These compounds also showed the suppression of SOS-inducing activity against the other mutagens aflatoxin B1 (AfB1) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), which require liver-metabolizing enzymes, and UV irradiation. In addition to the antimutagenic activities of these compounds against furylfuramide, Trp-P-1 and activated Trp-P-1 were also assayed by the Ames test using S. typhimurium TA100.

Antimutagenic activity of phenylpropanoids from clove (Syzygium aromaticum).

Abstract: Phenylpropanoids that possess antimutagenic activity were isolated from the buds of clove (Syzygium aromaticum). The isolated compounds suppressed the expression of the umu gene following the induction of SOS response in the Salmonella typhimurium TA1535/pSK1002 that have been treated with various mutagens. The suppressive compounds were mainly localized in the ethyl acetate extract fraction of the processed clove. This ethyl acetate fraction was further fractionated by silica gel column chromatography, which resulted in the purification and subsequent identification of the suppressive compounds. Electron impact mass spectrometry, IR, and (1)H and (13)C NMR spectroscopy were then used to delineate the structures of the compounds that confer the observed antimutagenic activity. The secondary suppressive compounds were identified as dehydrodieugenol (1) and trans-coniferyl aldehyde (2). When using 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) as the mutagen, compound 1 suppressed 58% of the umu gene expression as compared to the controls at a concentration of 0.60 micromol/mL, with an ID(50) (50% inhibitory dose) value of 0.48 micromol/mL, and compound 2 suppressed 63% of the umu gene expression as compared to the controls at a concentration of 1.20 micromol/mL, with an ID(50) value of 0.76 micromol/mL. Additionally, compounds 1 and 2 were tested for their ability to suppress the mutagenic activity of other well-known mutagens such as 4-nitroquinolin 1-oxide (4NQO) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), which do not require liver metabolizing enzymes, and aflatoxin B(1) (AfB(1)) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), which require liver metabolizing enzymes and activated Trp-P-1 and UV irradiation. Compounds 1 and 2 showed dramatic reductions in their mutagenic potential of all of the aforementioned chemicals or treatment. For the search of the structure-activity relationship, the derivatives of 1 and 2 (1a and 2a-c) were also assayed with all mutagens. Finally, the antimutagenic activities of compounds 1, 1a, 2, and 2a-c against furylfuramide, Trp-P-1, and activated Trp-P-1 were assayed by the Ames test using the S. typhimurium TA100 strain.

Tyrosinase Inhibitor from Black Rice Bran

Abstract: The inhibitor of tyrosinase activity in black rice bran was investigated. The methanol extract from black rice bran was re-extracted with hexane, chloroform, ethyl acetate, or water. The ethyl acetate extract had the most potent inhibition against tyrosinase activity by 80.5% at a concentration of 0.4 mg/mL. Inhibitory compound in the ethyl acetate fraction was isolated by silica gel column chromatography, and identified as protocatechuic acid methyl ester (compound 1) by GC, GC−MS, IR, and 1H and 13C NMR spectroscopy. Compound 1 inhibited 75.4% of tyrosinase activity at a concentration of 0.50 μmol/mL. ID50 (50% inhibition dose) value of compound 1 was 0.28 μmol/mL. To study the structure−activity relationship, protocatechuic acid (2), vanillic acid (3), vanillic acid methyl ester (4), isovanillic acid (5), isovanillic acid methyl ester (6), veratric acid (7), and veratric acid methyl ester (8) were also assayed. Keywords: Black rice bran; tyrosinase activity; protocatechuic acid methyl ester; structure−...

Volatile components from the roots of Scrophularia ningpoensis Hemsl.

Abstract: The composition of the volatile oil from the radix of Scrophularia ningpoensis has been investigated by capillary GC, GC–MS. The oil contained 103 volatile components, of which 3.49% were terpenoids. The main constituents were fatty acids, such as palmitic acid (25.40%), linoleic acid (10.04%), α-linolenic acid (6.06%), γ-linolenic acid (4.82%), cis-palmitoleic acid (3.94%), trans-oleic acid (3.52%), cis-oleic acid (2.67%) and trans-palmitoleic acid (1.20%). Copyright © 2003 John Wiley & Sons, Ltd.

Components of the essential oil from Petasites japonicus

Abstract: The components of the essential oil from the leaves, roots and flower stems of Petasites japonicus were analysed by GC and GC–MS. As a result, 69 compounds, amounting to 84–91% of the total oil, were characterized. The major components of the leaf essential oil were β-caryophyllene (22%) and valencene (15%). The root oil contained angelic acid (18%), eremophilene (10%) and α-phellandrene (10%) as the major components. On the flower stem oil, valencene (12%), α-phellandrene (11%) were the main components. Copyright © 2003 John Wiley & Sons, Ltd.

Roles of human CYP2A6 and 2B6 and rat CYP2C11 and 2B1 in the 10-hydroxylation of (-)-verbenone by liver microsomes.

Abstract: (-)-Verbenone, a monoterpene bicyclic ketone, is a component of the essential oil from rosemary species such as Rosmarinus officinalis L., Verbena triphylla, and Eucalyptus globulus and is used for an herb tea, a spice, and a perfume. In this study, (-)-verbenone was found to be converted to 10-hydroxyverbenone by rat and human liver microsomal cytochrome p450 (p450) enzymes. The product formation was determined by high-performance liquid chromatography with UV detection at 251 nm. There was a good correlation between activities of coumarin 7-hydroxylation and (-)-verbenone 10-hydroxylation catalyzed by liver microsomes of 16 human samples, indicating that CYP2A6 is a principal enzyme in (-)-verbenone 10-hydroxylation in humans. Human recombinant CYP2A6 and CYP2B6 catalyzed (-)verbenone 10-hydroxylation at Vmax values of 15 and 21 nmol/min/nmol p450 with apparent Km values of 16 and 91 microM, respectively. In contrast, rat CYP2A1 and 2A2 did not catalyze (-)-verbenone 10-hydroxylation at all, suggesting that there were species-related differences in the catalytic properties of human and rat CYP2A enzymes in the metabolism of (-)-verbenone. In the rat, recombinant CYP2C11, CYP2B1, and CYP3A2 catalyzed (-)-verbenone 10-hydroxylation with Vmax and Km ratios (ml/min/nmol p450) of 0.73, 0.20, and 0.03, respectively. Male-specific CYP2C11 was a major enzyme in (-)-verbenone 10-hydroxylation by untreated rat livers, and CYP2B1 catalyzed this reaction in liver microsomes of phenobarbital-treated rats. Rat CYP2C12, a female-specific enzyme, did not catalyze (-)verbenone 10-hydroxylation. These results suggest that human CYP2A6 and rat CYP2C11 are the major catalysts in the metabolism of (-)-verbenone by liver microsomes and that there are species-related differences in human and rat CYP2A enzymes and sex-related differences in male and female rats in the metabolism of (-)-verbenone.

Antimutagenic Activity of Sakuranetin from Prunus Jamasakura

Abstract: Sakuranetin (compound 1) from bark of Prunus jamasakura showed a suppressive effect on umu gene expression of SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen furylfuramide. Gene expression was suppressed 83% at a concentration of 0.70 μmol/mL. The ID50 value of compound 1 was 0.30 μmol/mL. This compound showed the suppression of 4NQO, MNNG, Trp-P-1, AfB1, activated Trp-P-1, and UV irradiation-induced SOS response. The methylated derivative (compound 2) of compound 1 showed less suppressive effect against all mutagens than compound 1. The antimutagenic activities of compounds 1 and 2 against furylfuramide, Trp-P-1, and activated Trp-P-1 were assayed by the Ames test using the S. typhimurium TA100 strain.

Volatile components of the rhizomes of Cirsium japonicum DC

Abstract: The chemical composition of the essential oils from the rhizomes of Cirsium japonicum DC. has been investigated by GC and GC–MS. Sixty-seven components were identified in the essential oil, with palmitic acid (14.42%), caryophyllene oxide (12.57%), khusinol (6.31%), pentadecanoic acid (6.28%) and myristic acid (4.66%) as the major components. Terpenoids accounted for about 45.22%, especially sesquiterpenoids, which comprised 42.17% of the essential oil. Copyright © 2002 John Wiley & Sons, Ltd.

Biotransformation of l-menthol by twelve isolates of soil-borne plant pathogenic fungi (Rhizoctonia solani) and classification of fungi

Abstract: The microbial transformation of l-menthol (1) was investigated by using 12 isolates of soil-borne plant pathogenic fungi, Rhizoctonia solani (AG-1-IA Rs24, Joichi-2, RRG97-1; AG-1-IB TR22, R147, 110.4; AG-1-IC F-1, F-4, P-1; AG-1-ID RCP-1, RCP-3, and RCP-7) as a biocatalyst. Rhizoctonia solani F-1, F-4 and P-1 showed 89.7–99.9% yields of converted product from 1, RCP-1, RCP-3, and RCP-7 26.0–26.9% and the other isolates 0.1–12.0%. In the cases of F-1, F-4 and P-1, substrate 1 was converted to (−)-(1S,3R,4S,6S)-6-hydroxymenthol (2), (−)-(1S,3R,4S)-1-hydroxymenthol (3) and (+)-(1S,3R,4R,6S)-6,8-dihydroxymenthol (4), which was a new compound. Substrate 1 was converted to 2 and/or 3 by RRG97-1, 110.4, RCP-1, RCP-3 and RCP-7. The structures of the metabolic products were elucidated on the basis of their spectral data. In addition, metabolic pathways of the biotransformation of 1 by Rhizoctonia solani are discussed. Finally, from the main component analysis and the differences in the yields of converted product from 1, the 12 isolates of Rhizoctonia solani were divided into three groups based on an analysis of the metabolites. Copyright © 2003 Society of Chemical Industry

Suppression of Chemical Mutagens-Induced SOS Response by Phenolic Acids from Black Rice Bran Using Salmonella typhimurium TA1535/pSK1002 umu Test

Abstract: A methanol extract from black rice bran showed a suppressive effect of the SOS-inducing activity on the mutagen 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) in the Salmonella typhimurium TA1535/pSK1002 umu test. The methanol extract was re-extracted with hexane, chloroform, ethylacetate, butanol and water. The ethylacetate fraction showed a suppressive effect. Suppressive compounds in an acidic fraction of the ethylacetate fraction were isolated by silica gel column chromatography and identified as vanillic acid (1) and protocatechuic acid (2) by GC, GC/MS, IR and 1H and 13C NMR spectroscopy. Compounds 1 and 2 suppressed the furylfuramide-induced SOS response in the umu test. Compounds 1 and 2 suppressed 37.7 and 44.5% of the SOS-inducing activity on furylfuramide at a concentration of 1.20 μ mol/mL. These compounds were assayed with other mutagens, 4-nitroquinolin 1-oxide (4NQO) and N -methyl-N ′-nitro-N -nitrosoguanidine (MNNG), which do not require liver metabolizing enzymes. In addition, compounds 1 and 2 were assayed with aflatoxin B1 (AfB1) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), which require liver metabolizing enzymes. These compounds showed suppressive effects of the SOS-inducing activity against furylfuramide, 4NQO, MNNG, AfB1 and Trp-P-1. To research the structure-activity relationship, veratric acid (3) as a similar compound of 1 and methyl esters of 1,2 and 3 (1Me, 2Me and 3Me) were also assayed with all chemical mutagens. Compounds 1Me, 2Me and 3Me exhibited stronger suppressive effects of the SOS-inducing activity against all chemical mutagens than 1,2 and 3.

Helicobacter pylori motility inhibitor

Abstract: PROBLEM TO BE SOLVED: To provide a Helicobacter pylori motility inhibitor as an active ingredient which is safer and has anti-Helicobacter pylori activity with slight side effects. SOLUTION: The Helicobacter pylori motility inhibitor comprises as active ingredient a compound of the general formula[I][ wherein, R 1 is OH, an alkoxy or acyl; R 2 and R 3 are each H, OH, an alkoxy or acyl, or a group of formula:O(CH 2 ) n O( n is 1, 2 or 3 ) with R 1 and R 2 are joined each other at their terminals; R 4 is OH, an alkoxy or acyl; R 5 and R 6 are each H, OH, an alkoxy or acyl, or a group of formula:O(CH 2 ) m O( m is 1, 2 or 3 ) with R 4 and R 5 are joined each other at their terminals ]. COPYRIGHT: (C)2005,JPO&NCIPI

Tyrosinase inhibitor and bleaching cosmetic using the same

Abstract: PROBLEM TO BE SOLVED: To obtain a new tyrosinase inhibitor, and to prepare a bleaching cosmetic which has excellent bleaching effects for preventing or improving abnormal melamine pigmentation in the skin, and the like, little produces side effects, and has excellent safety for the skin. SOLUTION: This tyrosinase inhibitor contains a compound represented by formula (I) (R is H or an alkyl) or its salt as an active ingredient, and the bleaching cosmetic contains the tyrosinase inhibitor. COPYRIGHT: (C)2005,JPO&NCIPI

Convenient Synthesis of Arylmethylenesuccinic Acids via Wittig Reaction

Abstract: A half ester of arylmethylenesuccinic acids were easily prepared by reaction of aromatic aldehydes with 2-carboxy-1-ethoxycarbonylethyltriphenylphosphorane in DMSO at 40°C in good yield. And also, the conversion of this half esters into the corresponding naphthoates were examined.

Lytic activity of l-menthol derivatives against the snow blight disease fungus, Micronectriella nivalis.

Abstract: Lytic activity of l-menthol (1) derivatives [(−)-(1S,3R,4S,6S)-6-hydroxymenthol (2), (−)-(1S,3R,4S)-1-hydroxymenthol (3), and (+)-(1S,3R,4R,6S)-6,8-dihydroxymenthol (4)] against the snow blight disease fungus, Micronectriella nivalis was investigated. Compounds 2, 3, and 4 had 85.0, 63.9, and 81.9% lytic activity, respectively, at a concentration of 0.2 mg/mL. The activity of each of the three compounds increased in a dose−response manner. To study the structure−activity relationship, acetyl esters of 1−4 [(−)-menthyl acetate (1Ac), (−)-6-hydroxymenthyl diacetate (2Ac), (−)-1-hydroxymenthyl 3-monoacetate (3Ac), and (−)-6,8-dihydroxymenthyl 3,6-diacetate (4Ac)] were synthesized with yields of 80.2−99.8% and were also assayed. The acetyl esters of 1Ac, 2Ac, 3Ac, and 4Ac had 51.2, 91.5, 66.0, and 95.2% lytic activity, respectively, at a concentration of 0.2 mg/mL, and these compounds showed further high lytic activity compared with the alcohols of 1−4. These acetyl esters also showed higher lytic activity as...