Stability Analyses by HPLC-MS of Guanitoxin Isolated from Sphaerospermopsis torques-reginae
Stability Analyses by HPLC-MS of Guanitoxin Isolated from Sphaerospermopsis torques-reginae
复制标题
DOI：
10.21577/0103-5053.20210053
复制
发表时间：
2021-08-01
影响因子：
1.4
通讯作者：
Pinto, Ernani
中科院分区：
文献类型：
--
作者：
Fernandes, Kelly A.;Dörr, Felipe Augusto;Pinto, Ernani
鸟苷毒素（Guanitoxin，GNT）是由淡水蓝藻产生的一种天然有机磷化合物，它能抑制乙酰胆碱酯酶的活性位点，阻止胆碱酯酶的水解，从而引起神经肌肉系统的严重紊乱。尽管具有像合成有机磷酸盐一样的化学结构，但仍然没有用于环境和淡水监测的分析标准。因此，本研究考察了GNT在不同储存条件、pH值和温度下的稳定性。该毒素由蓝细菌Sphaerospermopsis torques-reginae产生，并通过液相色谱-质谱联用（LC-MS）和LC-MS/MS进行监测，以鉴定和验证其稳定性。形成的主要降解产物是毒素的羟基-氨基-胍基衍生物。结果还表明，GNT在酸性介质（pH = 3.0）中稳定，但在室温（> 23 ℃）下可在96 h内逐渐降解。S.含GNT的Torques-reginae在低于4 ℃的冰箱中储存时保持稳定。此外，当从新鲜S. torques-reginae细胞比来自冻干材料。因此，这里所示的结果有助于有价值的信息的研究，目的是在原水和蓝藻水华样品中的GNT的分离，鉴定和监测。
Guanitoxin (GNT) is a natural organophosphate produced by some species of freshwater cyanobacteria, which inhibits the active site of acetylcholinesterase, preventing the hydrolysis of cholinesterases and consequently causing serious disturbances in the neuromuscular system. Despite having a chemical structure like synthetic organophosphates, there is still no analytical standard available for environmental and freshwater monitoring. Therefore, this study investigated the stability of GNT under different storage conditions, pH, and temperature. The toxin is produced by the cyanobacterium Sphaerospermopsis torques-reginae and monitored by liquid chromatography coupled to mass spectrometry (LC-MS) and LC-MS/MS for the identification and verification of its stability. The main degradation product formed is the hydroxy-amino-guanidinic derivative of the toxin. The results also indicate that GNT is stable in acidic medium (pH = 3.0), but can gradually degrade at room temperature (> 23 oC) over a period of 96 h. Lyophilized biomass of S. torques-reginae containing GNT remained stable when stored in a refrigerator below 4 oC. In addition, the extraction yield is higher when prepared from fresh S. torques-reginae cells than from lyophilized material. Thus, the results shown here contribute with valuable information for studies that aim at the isolation, identification, and monitoring of GNT in samples of raw water and cyanobacterial blooms.