Serna-Galvis Efraim A, Silva-Agredo Javier, Giraldo-Aguirre Ana L, Flórez-Acosta Oscar A, Torres-Palma Ricardo A
Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia.
Grupo de Diseño y Formulación de Medicamentos, Cosméticos y Afines (DYFOMECO), Facultad de Ciencias Farmacéuticas y Alimentarias, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia.
Ultrason Sonochem. 2016 Jul;31:276-83. doi: 10.1016/j.ultsonch.2016.01.007. Epub 2016 Jan 7.
This work studies the sonochemical degradation of a penicillinic antibiotic (oxacillin) in simulated pharmaceutical wastewater. High frequency ultrasound was applied to water containing the antibiotic combined with mannitol or calcium carbonate. In the presence of additives, oxacillin was efficiently removed through sonochemical action. For comparative purposes, the photo-Fenton, TiO2 photocatalysis and electrochemical oxidation processes were also tested. Therefore, the evolution of the antibiotic and its associated antimicrobial activity (AA) were monitored. A high inhibition was found for the other three oxidation processes in the elimination of the antimicrobial activity caused by the additives; while for the ultrasonic treatment, a negligible effect was observed. The sonochemical process was able to completely degrade the antibiotic, generating solutions without AA. In fact, the elimination of antimicrobial activity showed an excellent performance adjusted to exponential kinetic-type decay. The main sonogenerated organic by-products were determined by means of HPLC-MS. Four intermediaries were identified and they have modified the penicillinic structure, which is the moiety responsible for the antimicrobial activity. Additionally, the possible oxacillin sonodegradation mechanism was proposed based on the evolution of the by-products and their chemical structure. Furthermore, the high-frequency ultrasound action over 120 min readily removed oxacillin and eliminated its antimicrobial activity. However, the pollutant was not mineralized even after a long period of ultrasonic irradiation (360 min). Interestingly, the previously sonicated water containing oxacillin and both additives was completely mineralized using non-adapted microorganisms from a municipal wastewater treatment plant. These results show that the sonochemical treatment transformed the initial pollutant into substances that are biotreatable with a typical aerobic biological system.
本研究探讨了在模拟制药废水中，青霉素类抗生素（苯唑西林）的声化学降解情况。将高频超声应用于含有抗生素并添加了甘露醇或碳酸钙的水中。在添加剂存在的情况下，苯唑西林通过声化学作用被有效去除。为作比较，还测试了光芬顿法、二氧化钛光催化法和电化学氧化法。因此，监测了抗生素及其相关抗菌活性（AA）的变化。发现其他三种氧化过程在消除添加剂引起的抗菌活性方面有很高的抑制作用；而对于超声处理，观察到的影响可忽略不计。声化学过程能够完全降解抗生素，产生无抗菌活性的溶液。事实上，抗菌活性的消除表现出符合指数动力学类型衰减的优异性能。主要的声致有机副产物通过高效液相色谱 - 质谱法测定。鉴定出四种中间体，它们改变了青霉素结构，而青霉素结构是负责抗菌活性的部分。此外，根据副产物的演变及其化学结构，提出了苯唑西林可能的声降解机制。此外，120分钟以上的高频超声作用能迅速去除苯唑西林并消除其抗菌活性。然而，即使经过长时间的超声辐照（360分钟），污染物也未矿化。有趣的是，使用来自城市污水处理厂的未驯化微生物，可将先前含有苯唑西林和两种添加剂的超声处理后的水完全矿化。这些结果表明，声化学处理将初始污染物转化为可通过典型好氧生物系统进行生物处理的物质。
