Novobiocin Antimicrobic Supplement BD Difco™ 6 x 10 ml. Contains 20 mg of novobiocin. May be used with:- EC Medium Modified (Cat. No. 234020) or- Rappaport-Vassiliadis (MRSV) Medium Semisolid Modification (Cat. No. 218681) or- Brilliant Green Agar (Cat. No. 228530).