为了比较不同废水中残留抗生素及其相关物质的抑菌活性,利用建立的废水残留效价测定方法优选出抑菌活性强、效价线性范围宽的参照抗生素进行抗生素生产废水效价当量测定。以金黄色葡萄球菌(革兰氏阳性菌)作为标准菌株,通过不同抗生素的效价标准曲线从20种抗生素中优选出线性范围宽、抑菌能力强和便宜易得的红霉素作为标准参照抗生素。对土霉素和螺旋霉素2种生产废水的残留效价进行测定,发现用红霉素效价当量与土霉素/螺旋霉素效价当量表征呈显著正相关(p〈0.01),表明红霉素可以作为标准参照抗生素。利用此方法测定了4类不同抗生素生产废水的红霉素效价当量(平均值分别为土霉素生产废水11.40 mg·L-1,螺旋霉素生产废水1.66 mg·L-1,磺胺甲恶唑生产废水0.56 mg·L-1,6-氨基青霉烷酸生产废水0 mg·L-1),与几种抗生素本身的抑菌能力的排序一致。
To assess the residual antibacterial potencies of antibiotics and related substances in antibiotic production wastewater effluents,a real-time quantitative method was developed that was based on potency equiva- lent values. In this research,Staphylococcus aureus was used as the standard bacterial strain for testing and eryth- romycin (ERM) was selected as the standard reference antibiotic among 20 different antibiotics because of its high potency and wide linear concentration-response range in standard curves. Residual potencies of oxytetracy- cline and spiramycin in wastewater were determined and ERM equivalent quantities (ERM EQ) were significant- ly correlated with oxytettracycline/spiramycin equivalent quantities (P 〈 0.01 ), which supports the validity of employing ERM as the standard reference antibiotic. This method was then used to determine the ERM EQ values for four different antibiotic production wastewater samples. The average value for oxytetraeycline production wastewater was 11.40 mg · L-1, the average value for spiramycin production wastewater was 1.66 mg · L-t, the average value for sulfamethoxazole production wastewater was 0.56 mg· L-1, and the average value for 6-amin- openicillanic acid was 0 mg · L-1. The values were in accordance with the antibacterial potencies of these four antibiotics.