Emi Ohta

Endogenous pine wood nematicidal substances in pines, Pinus massoniana, P. strobus and P. palustris

Abstract The presence of the repellents and nematicides to the pine wood nematode, Bursaphelenchus xylophilus, was found in the heartwood and bark of Pinus massoniana, P. strobus and P. palustris, which have a resistance to the pine wood nematode. The heartwood of P. massoniana contained a repellent, α-humulene and two nematicidal substances, pinosylvin monomethylether (PSM) and (−)-nortrachelogenin for the nematode. The bark of the pine contained two nematicides, methyl ferulate and (+)-pinoresinol. PSM, which showed the highest nematicidal activity (LD50 was 4 ppm), was also contained in the heartwood of P. strobus and the heartwood and bark of P. palustris. The resistance of these pines to the pine wood nematode is considered to be attributed to the presence of these endogenously defending substances. Further, the relationship between the structure and the nematicidal activity was elucidated for PSM and methyl ferulate. Moreover, PSM showed little anti-acetylcholinesterase activity.

C-Geranylated Chalcones from the Stems of Angelica keiskei with Superoxide-Scavenging Activity

An ethyl acetate-soluble fraction of a methanol extract from the stems of Angelica keiskei was subjected to chromatographic separation to give three new chalcones, designated as xanthokeismins A-C (1-3), in addition to a known chalcone, xanthoangelol B (4). The structures of 1-3 were determined on the basis of the analysis of their spectroscopic data. Compounds 1-4 exhibited potent superoxide-scavenging activity.

Novel norsesterterpenes, which inhibit gastrulation of the starfish embryo, from the marine sponge Rhopaloeides sp.

Abstract Two new norsesterterpenes, rhopaloic acids B ( 2 ) and C ( 3 ), have been isolated from the marine sponge Rhopaloeides sp. together with the known rhopaloic acid A ( 1 ). Their structures have been elucidated by spectroscopic methods. Compounds 1, 2, and 3 potently inhibited gastrulation of the starfish ( Asterina pectinifera ) embryo, whereas hydrogenation or esterification resulted in loss of the inhibitory activity. Furthermore, methacrylic acid ( 9 ) did not affect embryonic development. these results suggest that the α-exo-methylene carboxyl functionality attached to a tetrahydropyran ring is essential for the inhibitory activity of 1–3 . The structures of rhopaloic acid B ( 2 ) and rhopaloic acid C ( 3 ) were determined on the basis of their spectroscopic data. Download full-size image

Ancorinoside A Mg salt from the marine sponge, Ancorina sp., which specifically inhibits blastulation of starfish embryos

Abstract A new tetramic acid Mg salt, ancorinoside A Mg salt, has been isolated from the marine sponge Ancorina sp. together with the known ancorinoside A. The structure of ancorinoside A Mg salt has been established on the basis of spectroscopic and chemical investigations and chemical correlations. Ancorinoside A Mg salt potently inhibited blastulation of the starfish (Asterina pectinifera) embryo.

Bioactive jatrophane diterpenes from Euphorbia guyoniana

Chromatographic investigation of the methylenechloride/methanol extract of the aerial parts of Euphorbia guyoniana afforded two jatrophane diterpenes, designated guyonianins E and F, in addition to a known jatrophane diterpene. The structures of the compounds were determined by comprehensive NMR analyses, including DEPT, COSY, HMQC, HMBC, NOESY and HRMS. These compounds exhibited cytotoxicity against human embryonic kidney 293 (HEK293) cells with IC(50) values of 35-100 microM.

Circulating free DNA as non-invasive diagnostic biomarker for childhood solid tumors.

PURPOSE Our aims are to determine circulating free DNA (cfDNA) in childhood solid tumor patients who underwent surgical intervention and to analyze any relationships with clinical parameters. METHODS Fourty-four consenting children admitted with solid tumors between 2010 and 2014 were recruited. CfDNAs isolated from 0.5mL plasma obtained before and 1-30days after surgery were analyzed by next-generation sequencing (NGS: IonTorrent Cancer Hotspot panel) and by gene amplification analysis using a digital PCR (dPCR) platform. RESULTS Total amounts of cfDNA were 54-825ng and were significantly associated with stage of disease. In cfDNA, 15 mutations or deletions (2 ALK, 2 TP53, 1 WT1, 3 CTNNB1, 1 APC, 1 KIT, 1 RET, 1 CDNK2AT, and 3 SMARCB1) were identified. In 10 neuroblastoma suspected cases, 2 showed high copy numbers of MYCN using dPCR. The positive rate in our cohort was 36%, and all of these aberrations were detected in the original tumors. None of the aberrations were detectable in cfDNA after surgery except for three cases whose tumors remained after surgery. CONCLUSIONS These data demonstrate the feasibility and potential utility of mutation/deletion/amplification screening in cfDNA using NGS and dPCR for the detection of tumor biomarkers in children with solid tumors. These markers also have the potential utility to evaluate complete resection after surgery.

Piericidins C5 and C6: new 4-pyridinol compounds produced by Streptomyces sp. and Nocardioides sp.

Piericidins C5 (1) and C6 (2), two new members of the piericidin family, were isolated from a Streptomyces sp. and a Nocardioides sp., together with known piericidins C1 (3), C2 (4), C3 (5), C4 (6), D1 (7), and A3 (8). The structures were determined on the basis of their spectroscopic data. Both new compounds inhibited cell division of fertilized starfish (Asterina pectinifera) eggs at the minimum inhibitory concentration of 0.09 microg/mL.

Exiguamide, a new spirocyclic sesquiterpene from the marine sponge Geodia exigua that inhibits cell fate specification during sea urchin embryogenesis

A new nitrogen-containing bicyclic spirosesquiterpene designated exiguamide which inhibited cell fate specification during sea urchin embryogenesis has been isolated from the marine sponge Geodia exigua. Its structure was determined by interpretation of spectral data and X-ray crystallographic analysis.

Dorsamin-A’s, Glycerolipids Carrying a Dehydrophenylalanine Ester Moiety from the Seed-Eating Larvae of the Bruchid Beetle Bruchidius dorsalis

Using a TLC autographic assay for radical-scavenging activity with the ABTS radical, the presence of lipophilic antioxidants in the larvae of the wild bruchid seed beetle Bruchidius dorsalis was detected. Assay-guided fractionation of the CHCl3-soluble fraction of the larvae resulted in the isolation of new glycerolipids, designated dorsamin-A763, -A737, -A765, -A739, and -A767, comprising 1,2-diacyl-sn-glycero-3-dehydrophenylalanine ester structural units. The ABTS radical scavenging activity of the dorsamin-As was comparable with or stronger than that of Trolox.

A C31-secodammarane-type triterpenic acid, 12-deoxy alnustic acid, from the female flowers of alnus pendula

Abstract A new C 31- -secodammarane-type triterpenic acid, 12-deoxy alnustic acid, was isolated from the female flowers of Alnus pendula . Its structure was elucidated to be (20S)-20-hydroxy-24-methylene-3,4-secodainmar-4(28)-en-3-oic acid by a combination of chemical and spectroscopic methods.