Transformation Pathways of the Recalcitrant Pharmaceutical Compound Carbamazepine by the White-Rot Fungus Pleurotus ostreatus: Effects of Growth Conditions.
Transformation Pathways of the Recalcitrant Pharmaceutical Compound Carbamazepine by the White-Rot Fungus Pleurotus ostreatus: Effects of Growth Conditions.
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DOI：
10.1021/acs.est.5b02222
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发表时间：
2015-09
影响因子：
11.4
通讯作者：
Naama Golan-Rozen;B. Seiwert;Christina Riemenschneider;T. Reemtsma;B. Chefetz;Y. Hadar
中科院分区：
文献类型：
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作者：
Naama Golan-Rozen;B. Seiwert;Christina Riemenschneider;T. Reemtsma;B. Chefetz;Y. Hadar
广泛使用的抗惊厥药物卡马西平在许多环境利基中具有顽固性，因此对废水处理提出了挑战。我们跟踪了白腐菌平菇在液体培养中对卡马西平的分解情况，并与木质纤维为底物的固态发酵进行了比较，在固态发酵中，不同的酶系统具有活性。采用LC-Q-TOF-MS联用技术鉴定卡马西平代谢物。在液体培养中，卡马西平只能转化为10，11-环氧卡马西平和10，11-二羟基卡马西平。在固态发酵过程中，卡马西平的代谢导致另外22种转化产物的产生，其中一些是有毒的。在固态发酵条件下，10，11-环氧卡马西平通过吖啶途径和10，11-二羟基卡马西平途径进一步代谢。后者通过5条亚途径进一步代谢。以~(14)C-羰基标记卡马西平为底物，培养63天后，~(14)C-CO_2释放量为初始放射性的17.4%。以代谢产物(10，11-环氧卡马西平、10，11-二羟基卡马西平和吖啶)为主要底物，跟踪它们在不同时间点的命运，对所提出的途径进行了验证。这项工作突出了生长条件对外源物质转化途径的影响。更好地了解生物修复处理过程中污染物的去向对于建立这类技术很重要。
The widely used anticonvulsant pharmaceutical carbamazepine is recalcitrant in many environmental niches and thus poses a challenge in wastewater treatment. We followed the decomposition of carbamazepine by the white-rot fungus Pleurotus ostreatus in liquid culture compared to solid-state fermentation on lignocellulosic substrate where different enzymatic systems are active. Carbamazepine metabolites were identified using liquid chromatography-high-resolution mass spectrometry (LC-Q-TOF-MS). In liquid culture, carbamazepine was only transformed to 10,11-epoxy carbamazepine and 10,11-dihydroxy carbamazepine as a dead-end product. During solid-state fermentation, carbamazepine metabolism resulted in the generation of an additional 22 transformation products, some of which are toxic. Under solid-state-fermentation conditions, 10,11-epoxy carbamazepine was further metabolized via acridine and 10,11-dihydroxy carbamazepine pathways. The latter was further metabolized via five subpathways. When (14)C-carbonyl-labeled carbamazepine was used as the substrate, (14)C-CO2 release amounted to 17.4% of the initial radioactivity after 63 days of incubation. The proposed pathways were validated using metabolites (10,11-epoxy carbamazepine, 10,11-dihydroxy carbamazepine, and acridine) as primary substrates and following their fate at different time points. This work highlights the effect of growth conditions on the transformation pathways of xenobiotics. A better understanding of the fate of pollutants during bioremediation treatments is important for establishment of such technologies.