58911-04-9Relevant academic research and scientific papers
Preparation of calibration standards of N1-H paralytic shellfish toxin analogues by large-scale culture of cyanobacterium Anabaena circinalis (TA04)
Watanabe, Ryuichi,Suzuki, Toshiyuki,Oshima, Yasukatsu
, p. 466 - 477 (2011)
Mouse bioassay is the official testing method to quantify paralytic shellfish toxins (PSTs) in bivalves. A number of alternative analytical methods have been reported. Some methods have been evaluated by a single laboratory validation. Among the different types of methods, chemical analyses are capable of identifying and quantifying the toxins, however a shortage of the necessary calibration standards hampers implementation of the chemical analyses in routine monitoring of PSTs in bivalves. In our present study, we studied preparation of major PST analogues as calibrants by large-scale cultivation of toxic freshwater cyanobacteria Anabaena circinalis TA04. The cells were steadily grown in 10 L bottle for 28 days. The primary N1-H toxins, C1/C2, were produced at a concentration of 1.3 ± 0.1 μmol/L. The intracellular and extracellular toxins occupied 80% and 20%, respectively. Over 220 μmol of the toxins was obtained from approximately 200 L of the culture over six months, demonstrating that it is sufficient to prepare saxitoxin analogues. The toxins were chemically converted to six N1-H analogues. Preparation of the analogues was carried out at relatively high yields (50-90%). The results indicate that our preparation method is useful to produce N1-H toxins. In our present study, detailed conditions for preparation of one of the rare N1-H analogues, gonyautoxin-5, were investigated.
DECARBAMOYLSAXITOXIN AND METHOD FOR PRODUCING ANALOG THEREOF
-
Paragraph 0125, (2017/03/08)
PROBLEM TO BE SOLVED: To provide a production method of an intermediate compound useful for efficiently producing decarbamoylsaxitoxin and an analog thereof. SOLUTION: A method for producing a compound represented by Formula (4) comprises a step I of treating a compound represented by Formula (2) and the like under a basic condition to produce a compound represented by Formula (3) and the like and a step II of reacting the compound represented by Formula (3) and the like with a compound having an SH group to produce a compound represented by Formula (4) and the like. The compound represented by Formula (4) can be utilized as a sample compound for toxicity evaluation of shellfish. (R1 is H or a hydroxyl group; R4 is an amino group or the like; and R5 is an univalent organic group) SELECTED DRAWING: None COPYRIGHT: (C)2017,JPO&INPIT
