Magnetic　cross-linked　enzyme　aggregates　(M-CLEAs)　were　prepared　for　Cerrena　laccase　and　used　in　antibiotic　treatment.　Of　the　seven　antibiotics　examined　in　this　study,　Cerrena　laccase　M-CLEAs　were　most　effective　in　degradation　of　tetracycline　(TC)　and　oxytetracycline　(OTC),　followed　by　ampicillin,　sulfamethoxazole　and　erythromycin.　The　redox　mediator　ABTS　was　not　able　to　improve　efficiencies　of　degradation　of　TC　and　OTC.　Cerrena　laccase　at　40　U/mL　eliminated　100　μg/mL　TC　at　pH　6　and　25　°C　in　48　h　in　the　absence　of　a　redox　mediator,　with　over　80%　degradation　occurring　within　the　first　12　h.　Laccase　treatment　also　significantly　suppressed　the　antimicrobial　activity　of　TC　and　OTC.　Three　TC　transformation　products,　the　levels　of　which　initially　increased　and　subsequently　decreased　during　laccase　treatment　were　identified　by　using　LC-TOF　MS.　A　mechanism　of　laccase-mediated　TC　oxidation　was　proposed　based　on　the　identified　intermediates.　©　2016　Elsevier　B.V.