Tryptic Soy Blood Agar Base EH Difco 228300, 500g. Used with blood for enhanced reactions of beta-hemolytic organisms after overnight incubation and for cultivation of fastidious microorganisms. Tryptic Soy Blood Agar Base EH Difco 228300 - buy online through Voigt Global Distribution, your dealer distributor for all BBL DIFCO BD Microbiology products.