Results 121 to 130 of about 543 (149)

Isolation, Chemistry, and Biochemistry of Ptaquiloside, a Bracken Carcinogen

Angewandte Chemie International Edition, 1998
A toxic and yet edible plant, bracken shows a carcinogenicity that has been a long-standing problem. This review provides an account of the isolation, structure, and reactivity of ptaquiloside (1), a bracken carcinogen. The elimination of glucose from 1 results in the formation of an ultimate carcinogen that alkylates the adenine and guanine residues ...
Kiyoyuki Yamada, Makoto Ojika, Hideo Kigoshi   +2 more
openaire   +1 more source

Ptaquiloside, a novel norsesquiterpene glucoside from bracken, var.

Tetrahedron Letters, 1983
Abstract An unstable norsesquiterpene glucoside with a novel illudane skeleton, ptaquiloside ( 1 ) has been isolated from bracken fern, Pteridium aquilinum var. latiusculum and the planar structure has been established on the basis of spectral and chemical means.
Haruki Niwa, Makoto Ojika, Kazumasa Wakamatsu, Kiyoyuki Yamada, Iwao Hirono, Kazuhiro Matsushita   +5 more
openaire   +1 more source

Genotoxic activity and inhibition of soil respiration by ptaquiloside, a bracken fern carcinogen

Environmental Toxicology and Chemistry, 2005
Abstract Ptaquiloside (PTA) is a natural toxin produced by bracken (Pteridium aquilinum [L.] Kuhn). Assessment of PTA toxicity is needed because PTA deposited from bracken to soil may leach to surface and groundwater. Inhibition of soil respiration and genotoxic activity of PTA was determined by a soil microbial carbon transformation ...
Schmidt, Bjørn, Rasmussen, Lars Holm, Svendsen, Gitte Winkel, Ingerslev, Flemming, Hansen, Hans Christian Bruun   +4 more
openaire   +2 more sources

Ptaquiloside, the Major Toxin of Bracken, and Related Terpene Glycosides: Chemistry, Biology and Ecology

ChemInform, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Kiyoyuki, Yamada, Makoto, Ojika, Hideo, Kigoshi   +2 more
openaire   +2 more sources

Cytotoxicity studies of quercetin, shikimate, cyclohexanecarboxylate and ptaquiloside.

Veterinary and human toxicology, 1996
A study was carried out to determine the cytotoxic effects of quercetin, shikimate, cyclohexane-carboxylate and ptaquiloside on Chinese hamster ovary (CHO), mouse fibroblast (3T3) and normal rat kidney (NRK) cells by cell growth inhibition assay of monolayers grown in 96-well plates.
A J, Ngomuo, R S, Jones
openaire   +1 more source

Screening for Ptaquiloside in Ferns: Using Herbarium Specimens for Qualitative Mapping Purposes

Phytochemical Analysis, 2017
AbstractIntroductionPtaquiloside (PTA) is a noxious carcinogen found widespread in Bracken (Pteridium sp.) but with scattered and unresolved distribution outside the genus. The carcinogen causes Bovine Enzootic Haematuria among cattle all‐over the World and is under suspicion of causing human cancers.ObjectiveTo set‐up a methodology for large‐scale ...
Lars Holm Rasmussen, Henrik Ærenlund Pedersen   +1 more
openaire   +3 more sources

Microbial degradation and impact of Bracken toxin ptaquiloside on microbial communities in soil

Chemosphere, 2007
The carcinogenic and toxic ptaquiloside (PTA) is a major secondary metabolite in Bracken fern (Pteridium aquilinum (L.) Kuhn) and was hypothesized to influence microbial communities in soil below Bracken stands. Soil and Bracken tissue were sampled at field sites in Denmark (DK) and New Zealand (NZ).
Engel, Pernille, Brandt, Kristian Koefoed, Rasmussen, Lars Holm, Ovesen, Rikke Gleerup, Sørensen, Jan   +4 more
openaire   +3 more sources

Stereocontrolled total synthesis of (±)-ptaquilosin, the aglycone of ptaquiloside, a bracken carcinogen

Tetrahedron Letters, 1989
Abstract Starting from α-allyl-δ-valerolactone, stereocontrolled synthesis of ptaquilosin (2), the aglycone of a bracken carcinogen ptaquiloside (1) has been achieved in racemic form, which includes a novel deformylation-hydroxylation reaction (21 → 23) as one of the key steps.
Hideo Kigoshi, Akihiko Sawada, Yoshisuke Nakayama, Haruki Niwa, Kiyoyuki Yamada   +4 more
openaire   +1 more source

Carcinogenicity in rats of ptaquiloside isolated from bracken.

Gan, 1985
The nature of the carcinogen present in bracken fern has not yet been elucidated. Very recently, we succeeded in isolating ptaquiloside, a novel norsesquiterpene glucoside of the illudane type, from bracken. Ptaquiloside was shown to be a carcinogenic principle of bracken fern. It induces mammary cancer and multiple ileal tumors in high incidences when
I, Hirono, S, Aiso, T, Yamaji, H, Mori, K, Yamada, H, Niwa, M, Ojika, K, Wakamatsu, H, Kigoshi, K, Niiyama   +9 more
openaire   +1 more source

Structure of ptaquiloside tetraacetate, C28H38O12

Acta Crystallographica Section C Crystal Structure Communications, 1984
S. Ohba, Y. Saito, I. Hirono, H. Niwa, M. Ojika, K. Wakamatsu, K. Yamada   +6 more
openaire   +1 more source