Results 141 to 150 of about 3,742 (170)

Tetrodotoxin and its analogues in extracts from the toad Atelopus oxyrhynchus (family: Bufonidae)

Toxicon, 1992
Tetrodotoxin and its analogues, 4-epitetrodotoxin and 4,9-anhydrotetrodotoxin, were detected in the toad Atelopus oxyrhynchus by HPLC analysis. The toxin and its analogues were still present in a specimen which lived 3.5 years in captivity.
Mari Yotsu-Yamashita, D Mebs, Takeshi Yasumoto   +2 more
exaly   +3 more sources

Variability of tetrodotoxin and of its analogues in the red-spotted newt, Notophthalmus viridescens (Amphibia: Urodela: Salamandridae)

Toxicon, 2012
Efts and adult specimens (n = 142) of the red-spotted newt Notophthalmus viridescens from various locations in Canada and USA were analyzed for the presence of tetrodotoxin (TTX) and of its analogues 6-epitetrodotoxin and 11-oxotetrodotoxin. Considerable individual variations in toxin levels were found within and among populations from New Hampshire ...
Mari Yotsu-Yamashita, Kenneth L Krysko, Christian Melaun   +2 more
exaly   +3 more sources

The voltage-gated sodium ion channel inhibitory activities of a new tetrodotoxin analogue, 4,4a-anhydrotetrodotoxin, and three other analogues evaluated by colorimetric cell-based assay

Toxicon, 2016
The voltage-gated sodium ion channel inhibitory activities of four tetrodotoxin analogues were evaluated for their ability to reduce the cytotoxicity of ouabain and veratridine in mouse neuroblastoma Neuro-2a cells. EC50 of the novel analogue, 4,4a-anhydrotetrodotoxin purified from pufferfish, was 750 fold larger than that of tetrodotoxin, supporting ...
Keiichi Konoki, Mari Yotsu-Yamashita
exaly   +3 more sources

Occurrence of 11-oxotetrodotoxin in the red-spotted newt, Notophthalmus viridescens, and further studies on the levels of tetrodotoxin and its analogues in the newt's efts

Toxicon, 2003
An analogue of tetrodotoxin (TTX), 11-oxoTTX, was semi-purified from the red-spotted newt, Notophthalmus viridescens, and identified by ESI-MS and 1H NMR spectra. The levels of TTX, 11-oxoTTX and 6-epiTTX in early stage of development (efts) of this newt were investigated by a post-column fluorescent-HPLC system, and compared with those of adult newts.
Mari Yotsu-Yamashita
exaly   +3 more sources

Synthesis of the 8-Deoxy Analogue of 4,9-Anhydro-10-hemiketal-5-deoxy-tetrodotoxin, a Proposed Biosynthetic Precursor of Tetrodotoxin

Organic Letters, 2021
Despite decades of research, the biosynthesis of tetrodotoxin, also known as a puffer fish toxin, remains an unsolved mystery. We disclose a synthesis of the 8-deoxy analogue of 4,9-anhydro-10-hemiketal-5-deoxy-tetrodotoxin, a possible biosynthetic precursor of tetrodotoxin isolated from the Japanese toxic newt, by an intramolecular radical cyclization
Tadachika Miyasaka, Masaatsu Adachi, Toshio Nishikawa   +2 more
openaire   +2 more sources

Changes in Tissue Distribution of Tetrodotoxin and Its Analogues in Association with Maturation in the Toxic Flatworm, Planocera multitentaculata

Marine Biotechnology, 2022
The toxic flatworm, Planocera multitentaculata, possesses highly concentrated tetrodotoxin (TTX), also known as pufferfish toxin, throughout its life cycle, including the egg and larval stages. Additionally, TTX analogues, 5,6,11-trideoxyTTX and 11-norTTX-6(S)-ol, have also been detected in the flatworm.
Hikaru, Oyama, Masaaki, Ito, Rei, Suo, Naoko, Goto-Inoue, Mizuki, Morisasa, Tsukasa, Mori, Haruo, Sugita, Tetsushi, Mori, Ryota, Nakahigashi, Masaatsu, Adachi, Toshio, Nishikawa, Shiro, Itoi   +11 more
openaire   +2 more sources

Tetrodotoxin and Its Analogues in Food: Recent Updates on Sample Preparation and Analytical Methods Since 2012

Journal of Agricultural and Food Chemistry, 2022
Tetrodotoxin (TTX), found in various organisms including pufferfish, is an extremely potent marine toxin responsible for numerous food poisoning accidents. Due to its serious toxicity and public health threat, detecting TTX and its analogues in diverse food matrices with a simple, fast, efficient method has become a worldwide concern.
Cong Hu, Yuan Zhang, Yu Zhou, Yang-jia-yi Xiang, Zhi-fei Liu, Zhi-hong Wang, Xue-song Feng   +6 more
openaire   +2 more sources

Total Synthesis of Chiriquitoxin, an Analogue of Tetrodotoxin Isolated from the Skin of a Dart Frog

Chemistry – A European Journal, 2014
AbstractThe first total synthesis of chiriquitoxin, the most structurally complex analogue of tetrodotoxin isolated from a Costa Rican dart frog, has been accomplished from a newly designed intermediate for a variety of tetrodotoxin derivatives. The synthesis includes the third total synthesis of tetrodotoxin in this laboratory, and its intermediate ...
Masaatsu, Adachi, Takuya, Imazu, Ryo, Sakakibara, Yoshiki, Satake, Minoru, Isobe, Toshio, Nishikawa   +5 more
openaire   +2 more sources

The occurrence of 11-oxotetrodotoxin, a rare tetrodotoxin analogue, in the brachycephalidae frog Brachycephalus ephippium

Toxicon, 2003
11-oxoTTX is an analogue 4-5 times more toxic than TTX itself, been rare even in marine animals. Two ions at m/z 320 and 336 corresponding to TTX and 11-oxoTTX (M+H(+)), respectively, were detected in the Brachycephalidae frog Brachycephalus ephippium extracts.
Osmindo R, Pires, Antonio, Sebben, Elisabeth Ferroni, Schwartz, Carlos, Bloch, Rodrigo A V, Morales, Carlos A, Schwartz   +5 more
openaire   +2 more sources

Tetrodotoxin and analogues in two local pufferfish species from Inhaca Island – South of Mozambique: First report in the Mozambican coast

Toxicon, 2022
Tetrodotoxins (TTXs) were investigated in two local pufferfish species, Diodon hystrix and Arothron hispidus, from Mozambican coast. TTX and analogues 4-epiTTX, 4,9-anhydroTTX, 11-deoxyTTX, and 11-norTTX-6-(R/S)-ol were found in both species and high level of TTX was found in A. hispidus (9522.0 μg TTX kg-1) than in D. hystrix (350.9 μg TTX kg-1).
Isidro José Tamele, Ilário Timba, Pedro Reis Costa, Vitor Vasconcelos   +3 more
openaire   +2 more sources