€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****ACTA PHARMACEUTICA SUECICA***** Malterud KE Faegri A Bacteriostatic and fungistatic activity of C-methylated dihydrochalcones from the fruits of Myrica gale L. In: Acta Pharm Suec (1982) 19(1):43-6 ISSN: 0001-6675 [No Abstract Available] Registry Numbers: 94-41-7 (Chalcone) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****BIOLOGICAL AND PHARMACEUTICAL BULLETIN***** Matsuda H Higashino M Chen W Tosa H Iinuma M Kubo M Studies of cuticle drugs from natural sources. III. Inhibitory effect of Myrica rubra on melanin biosynthesis. In: Biol Pharm Bull (1995 Aug) 18(8):1148-50 ISSN: 0918-6158 The inhibitory effect of a 50% ethanolic extract obtained from the dried leaves and the bark of Myrica rubra, was investigated in vitro on melanin biosynthesis which is closely related to hyperpigmentation. These extracts inhibited tyrosinase activity which converts dopa to dopachrome in the biosynthetic process. Furthermore, the extracts inhibited the production of melanin from dopachrome by autoxidation and also showed superoxide dismutase (SOD)-like activity. After bioassay-guided fractionation, quercetin, myricetin and myricetin 3-O-rhamnoside were isolated from the leaves. As they showed the inhibitory effect on tyrosinase activity, the activity is partially attributable to them in the extract of M. rubra. These results suggested that the leaves or the bark of M. rubra might be used as a whitening agent for the skin. Registry Numbers: EC 1.14.18.1 (Monophenol Monooxygenase) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****CHEMICAL AND PHARMACEUTICAL BULLETIN***** Sakurawi K Yasuda F Tozyo T Nakamura M Sato T Kikuchi J Terui Y Ikenishi Y Iwata T Takahashi K Konoike T Mihara S Fujimoto M Endothelin receptor antagonist triterpenoid, myriceric acid A, isolated from Myrica cerifera, and structure activity relationships of its derivatives. In: Chem Pharm Bull (Tokyo) (1996 Feb) 44(2):343-51 ISSN: 0009-2363 As the first non-peptide endothelin receptor antagonist from a higher plant, a new triterpenoid, myriceric acid A (50-235) (1) was isolated from the bayberry, Myrica cerifera. Myriceric acid A (1) inhibited not only an endothelin-1-induced increase in cytosolic free Ca2+ concentration (IC50 = 11 +/- 2 nM) but [125I]endothelin-1 binding in rat aortic smooth muscle cells (Ki = 66 +/- 15 nM). Two new related triterpenoids, myriceric acid C (6), and myriceric acid D (8), were also isolated. Furthermore, the chemical modification of these natural products led to the synthesis of sulfated derivatives (13, 14, 15) which showed 1.5 to 20 times higher affinity for endothelin receptors. The structure activity relationships of myriceric acids and their derivatives are discussed. Registry Numbers: 7440-70-2 (Calcium) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****EUROPEAN JOURNAL OF PHARMACOLOGY***** Mihara S Fujimoto M The endothelin ETA receptor-specific effect of 50-235, a nonpeptide endothelin antagonist. In: Eur J Pharmacol (1993 Jun 15) 246(1):33-8 ISSN: 0014-2999 We characterized the endothelin receptor antagonist 27-O-caffeoyl myricerone (50-235), isolated from the bayberry Myrica cerifera, using rat aortic smooth muscle A7r5 cells that express ETA receptors and human Girardi heart cells that express ETB receptors. 50-235 concentration-dependently inhibited 125I-ET-1 binding to A7r5 cells with Ki of 51 +/- 12 nM, while it had no effect on 125I-ET-1 and 125I- ET-3 bindings to Girardi heart cells. Also in affinity cross-linking studies with 125I-ET-1, 50-235 inhibited labeling of a protein of M(r) = 67,000 in A7r5 cells, but did not inhibit labeling of two proteins with M(r) values of 70,000 and 46,000 in Girardi heart cells. Functionally, 50-235 inhibited the ET-1-induced increase in cytosolic free Ca2+ concentration ([Ca2+]i) in a dose-dependent manner (IC50 = 11 +/- 2 nM) in A7r5 cells. On the other hand, this compound had no effect on the basal level of [Ca2+]i and the high K(+)- and bombesin-induced increases in [Ca2+]i in A7r5 cells, nor on the ET-1-induced increase in [Ca2+]i in Girardi heart cells. Also, 50- 235 inhibited ET-1-promoted mitogenesis of A7r5 cells. Thus, we conclude that 50-235 is a specific endothelin A receptor antagonist that could be very useful for elucidating the physiological and pathophysiological significance of ET. Registry Numbers: 142877-49-4 (myriceron caffeoyl ester) 7440-09-7 (Potassium) 7440-70-2 (Calcium) 9007-49-2 (DNA) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****FEBS LETTERS***** Fujimoto M Mihara S Nakajima S Ueda M Nakamura M Sakurai K A novel non-peptide endothelin antagonist isolated from bayberry, Myrica cerifera. In: FEBS Lett (1992 Jun 22) 305(1):41-4 ISSN: 0014-5793 A potent non-peptide ET receptor antagonist, myriceron caffeoyl ester (50-235), was isolated from the bayberry, Myrica cerifera. This compound selectively antagonized specific binding of [125I]ET-1, but not of [125I]ET-3, to rat cardiac membranes, ET-1-induced increase in the intracellular free calcium concentration in Swiss 3T3 fibroblasts, and ET-1-induced contraction of rat aortic strips. Thus, 50-235 is the first non-peptide ET(A) receptor antagonist. This compound can be useful for studying the physiological role of endothelin and exploring its role in various diseases. Registry Numbers: 142877-49-4 (myriceron caffeoyl ester) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****FREE RADICAL BIOLOGY AND MEDICINE***** Mathiesen L Malterud KE Sund RB Hydrogen bond formation as basis for radical scavenging activity: a structure-activity study of C-methylated dihydrochalcones from Myrica gale and structurally related acetophenones. In: Free Radic Biol Med (1997) 22(1-2):307-11 ISSN: 0891-5849 A naturally occurring flavonoid, myrigalone B (2',6' -dihydroxy-4'- methoxy-3',5'-dimethyl-dihydrochal-cone) is an effective antioxidant and scavenger of the diphenylpicrylhydrazyl radical, while the closely related angoletin (2',4'-dihydroxy-6'-methoxy-3',5'-dimethyl- dihydrochalcone) is inactive. From NMR spectra, it appears that myrigalone B has a time-averaged conformation in which the substituted aromatic ring is orthogonal to the carbonyl group, while angoletin is coplanar. By donating a phenolic hydrogen in radical scavenging, myrigalone B will lose its symmetrical structure and may thereby change to a coplanar conformation forming a strong intramolecular hydrogen bond between the remaining phenolic hydrogen and the carbonyl group. The energy gain entailed would then appear to be a driving force for the radical scavenging by myrigalone B. Angoletin, being coplanar, lacks this driving force. To verify this hypothesis, the conformation and radical scavenging activity of a series of phenolic acetophenones were studied. All substances that had an orthogonal conformation and could form intramolecular hydrogen bonds by loss of a phenolic hydrogen were DPPH scavengers, while compounds lacking these properties were inactive. From this, we propose that formation of intramolecular hydrogen bonds may lead to radical scavenging activity. Registry Numbers: 1898-66-4 (2,2-diphenyl-1-picrylhydrazyl) 64706-54-3 (Bepridil) 76444-55-8 (angoletin) 94-41-7 (Chalcone) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****JOURNAL OF PHARMACEUTICAL SCIENCES***** Paul BD Rao GS Kapadia GJ Isolation of myricadiol, myricitrin, taraxerol, and taraxerone from Myrica cerifera L. root bark. In: J Pharm Sci (1974 Jun) 63(6):958-9 ISSN: 0022-3549 [No Abstract Available] €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****MICROBIOLOGIA***** Pozuelo Gonzalez JM Gutierrez Manero FJ Llinares Pinel F Bermudez de Castro F [Density and activity of microorganisms of the carbon cycle under the canopy of Myrica gale L.] Densidad y actividad de microorganismos del ciclo del carbono bajo el dosel de Myrica gale L. In: Microbiologia (1992 Apr) 8(1):32-8 ISSN: 0213-4101 (Published in Spanish) Plants, especially actinorhizal, regulate edaphic microflora through various ways, modifying thus nutrients recycling. Myrica gale effect on microorganisms in the carbon cycle is studied in this work by comparing soil samples collected under the canopy in summer and control samples. The results indicate that under M. gale C-organic and N-total concentration and anaerobic cellulolytic, hemicellulolytic and amilolytic density increase, and pH, C/N ratio and aerobic cellulolytic microorganisms density decrease. Microbial activity in soil is also modified. Registry Numbers: 7440-44-0 (Carbon) 7727-37-9 (Nitrogen) 9004-34-6 (Cellulose) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****PHARMACOLOGY AND TOXICOLOGY***** Mathiesen L Malterud KE Nenseter MS Sund RB Inhibition of low density lipoprotein oxidation by myrigalone B, a naturally occurring flavonoid. In: Pharmacol Toxicol (1996 Mar) 78(3):143-6 ISSN: 0901-9928 The influence of myrigalone B, a flavonoid from the fruit exudate of Myrica gale L. on Cu(2+)-induced oxidation of low density lipoprotein from cholesterol fed rabbits was investigated. Myrigalone B was an effective antioxidant, as shown by its ability to dose-dependently prolong the lag time for the formation of conjugated dienes. A 100% increase in lag time corresponds to a myrigalone B concentration of 1.4 +/- 1.1 microM. For alpha-tocopherol, used as a reference, this effect corresponds to a concentration of 1.9 +/- 1.2 microM. Myrigalone B also dose-dependently reduced the maximum rate of formation of conjugated dienes, 1.4 microM causing a 15 +/- 5% reduction, but it had no influence on the maximal amount of conjugated dienes formed. Registry Numbers: 57-88-5 (Cholesterol) 9002-62-4 (Prolactin) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ Malterud KE Diep OH Sund RB C-methylated dihydrochalcones from Myrica gale L: effects as antioxidants and as scavengers of 1,1-diphenyl-2-picrylhydrazyl. In: Pharmacol Toxicol (1996 Feb) 78(2):111-6 ISSN: 0901-9928 A number of isomeric or chemically closely related C-methylated dihydrochalcones, which is a rare substance class, has been isolated from the fruit exudate of Myrica gale L. and subjected to the following tests: 1) inhibition of lipid peroxidation induced by tert- butyl hydroperoxide or bromotrichloromethane in isolated rat hepatocytes, 2) inhibition of peroxidation induced by Fe2+ ions in a cell free system with linolenic acid as substrate, 3) scavenging activity against the diphenylpicrylhydrazyl radical, and 4) inhibition of enzymatic lipid peroxidation in linoleic acid by soybean 15-lipoxy-genase. One of the compounds (myrigalone B = MyB; 2',6'-dihydroxy-4'-methoxy-3',5'-dimethyldihydrochalcone) showed good activity in all tests whereas the others were inactive or slightly active, except that myrigalone A (MyA; 3-(1-oxo-3-phenylpropyl)-1,1,5- trimethylcyclohexane-2,4,6-trione)) like its synthetic analogue MyA* (the polar part of MyA) was nearly as active as MyB in 4). The antioxidant properties of MyB are probably due to its radical scavenging activity and may be related to its conformation, which differs from that of the other compounds. Registry Numbers: EC 1.13.11.33 (Arachidonate 15-Lipoxygenase) 1083-30-3 (dihydrochalcone) 1898-66-4 (2,2-diphenyl-1-picrylhydrazyl) 64706-54-3 (Bepridil) 94-41-7 (Chalcone) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****PLANTA MEDICA***** Mathiesen L Malterud KE Sund RB Antioxidant activity of fruit exudate and C-methylated dihydrochalcones from Myrica gale. In: Planta Med (1995 Dec) 61(6):515-8 ISSN: 0032-0943 Antioxidant and radical scavenging effects were studied of a diethyl ether extract of the fruit exudate of Myrica gale L., and of C- methylated dihydrochalcones isolated from it. Isolated hepatocytes and liver mitochondria from the rat were incubated with tertbutyl hydroperoxide, and lipid peroxidation measured by the yield of thiobarbituric acid reactive substances. The main antioxidant of the extract, myrigalone B (MyB), inhibited lipid peroxidation in hepatocytes with an IC50 value of 23 +/- 1 microM, whereas in mitochondria the value was 5.2 +/- 0.1 microM. The fruit extract itself inhibited peroxidation in hepatocytes with an IC50 value of 7.0 +/- 0.2 microM calculated according to its MyB content, and in mitochondria with an IC50 of 1.7 +/- 0.1 microM. Other myrigalones were considerably less active or inactive as antioxidants. The IC50 of promethazine, an established inhibitor of lipid peroxidation, was 3.8 +/- 0.4 microM in mitochondria./ Both MyB and the fruit extract caused scavenging of the diphenylpicrylhydrazyl (DPPH) radical with IC50 values of 32 +/- 1 microM and 14 +/- 1 microM (as MyB), respectively. Peroxidation in linoleic acid catalyzed by soybean 15- lipoxygenase was inhibited by MyB (IC50 = 23 +/- 1 microM calculated as MyB; corresponding to an extract concentration of 71 +/- 3 microgram(s)/ml). However, the extract content of myrigalone A, itself a fairly potent inhibitor of 15-lipoxygenase, may contribute significantly to the latter effect. Registry Numbers: EC 1.13.11.33 (Arachidonate 15-Lipoxygenase) 1083-30-3 (dihydrochalcone) 1898-66-4 (2,2-diphenyl-1-picrylhydrazyl) 64706-54-3 (Bepridil) 94-41-7 (Chalcone) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ Gafner S Wolfender JL Mavi S Hostettmann K Antifungal and antibacterial chalcones from Myrica serrata. In: Planta Med (1996 Feb) 62(1):67-9 ISSN: 0032-0943 The dichloromethane extract of the leaves of Myrica serrata inhibits growth of Cladosporium cucumerinum, Bacillus subtilis, and Escherichia coli on TLC plates. Activity-guided fractionation led the isolation of 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (1), 2',4'-dihydroxy-6'-methoxy-5'-methylchalcone (aurentiacin A) (2), 2',6'-dihydroxy-4'-methoxy-3',5'-dimethyldihydrochalcone (3), 2'- hydroxy-4',6'-dimethoxy-3'-methyldihydrochalcone (4), and 2', 6'- dihydroxy-4'-methoxy-3'-methyldihydrochalcone (5). In addition, the flavanones demethoxymatteucinol (6) and cryptostrobin (7) were also identified. Registry Numbers: 94-41-7 (Chalcone) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ *****YAKUGAKU ZASSHI. JOURNAL OF THE PHARMACEUTICAL SOCIETY OF JAPAN***** Inoue T Arai Y Nagai M [Diarylheptanoids in the bark of Myrica rubra Sieb. et Zucc.] In: Yakugaku Zasshi (1984 Jan) 104(1):37-41 ISSN: 0031-6903 (Published in Japanese) [No Abstract Available] Registry Numbers: 32492-74-3 (myricanone) 33606-81-4 (myricanol) 90052-02-1 (myricanol-15-glucoside) €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ Inoue T [Constituents of Acer nikoense and Myrica rubra. On diarylheptanoids] In: Yakugaku Zasshi (1993 Mar) 113(3):181-97 ISSN: 0031-6903 (Published in Japanese) The diarylheptanoid constituents of the titled plants and their close plants were reviewed. Many new diarylheptanoids and their glycosides named acerogenin and aceroside were isolated from the stem bark of Acer nikoense, A. griseum and A. triflorum. Myricanone, myricanol and its five new glycosides were isolated from the stem bark of Myrica rubra, and myricanone and galeon, from the stem of M. gale var. tomentosa. The structures of these compounds were determined on the basis of chemical and spectral evidence, and chemotaxonomy of the above plants was briefly discussed. In addition biosynthesis of acerogenin A, revision of the structure for isomyricanone derived from myricanone, and some biological activities of A. nikoense and M. rubra were described. €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€ Ohta S Sakurai N Kamogawa A Yaguchi Y Inoue T Shinoda M [Protective effects of the bark of Myrica rubra Sieb. et Zucc. on experimental liver injuries] In: Yakugaku Zasshi (1992 Apr) 112(4):244-52 ISSN: 0031-6903 (Published in Japanese) The methanol extract from the bark of Myrica rubra SIEB. et ZUCC. showed protective effects on liver injuries induced by carbon tetrachloride (CCl4) and alpha-naphthylisothiocyanate (ANIT) in rats. In this study, the fractions and some compounds from the bark of M. rubra were investigated for the protection against CCl4 inducing liver injuries in rats. The active principles for the protection were recognized in two fractions (M-3 and M-5 Fr. 1) obtained from the methanol extract, and one of the active principles in the fraction (M- 3) was found to be myricanol 5-O-beta-D-(6'-O-galloyl)- glucopyranoside. In addition, these fractions protecting liver injuries induced by CCl4 showed significant protective effects against cholestasis induced by ANIT. €€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€€