Preparation of Calibration Standards of N1-H Paralytic Shellfish Toxin Analogues by Large-Scale Culture of Cyanobacterium Anabaena circinalis (TA04)
作者:Ryuichi Watanabe、Toshiyuki Suzuki、Yasukatsu Oshima
DOI:10.3390/md9030466
日期:——
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.
小鼠生物测定是量化双壳贝类中麻痹性贝类毒素 (PST) 的官方检测方法。据报道,有许多替代分析方法。有些方法已通过单一实验室验证进行评估。在不同类型的方法中,化学分析法能够鉴定和量化毒素,但由于缺乏必要的校准标准,阻碍了化学分析法在双壳贝类中麻痹性贝类毒素常规监测中的应用。在本研究中,我们研究了通过大规模培养有毒淡水蓝藻 Anabaena circinalis TA04 制备主要 PST 类似物作为校准物的方法。细胞在 10 升的瓶中稳定生长 28 天。产生的主要 N1-H 毒素 C1/C2 的浓度为 1.3 ± 0.1 µmol/L。细胞内和细胞外毒素分别占 80% 和 20%。在 6 个月的时间里,从大约 200 升培养液中获得了超过 220 µmol 的毒素,这表明它足以制备沙西毒素类似物。这些毒素通过化学方法转化为六种 N1-H 类似物。类似物的制备收率相对较高(50-90%)。结果表明,我们的制备方法有助于生产 N1-H 毒素。在本研究中,我们研究了制备一种罕见的 N1-H 类似物--龙葵毒素-5 的详细条件。