Casein Soyabean Digest HiCynthâ„¢ Agar (Soyabean Casein Digest HiCynthâ„¢ Agar) (Tryptone Soya HiCynthâ„¢ Agar) is a widely used medium, which supports the growth of wide variety of organisms even that of fastidious ones such as Neisseria, Listeria, and Brucella etc. Tryptone Soya Agar conforms as per USP (6) and is used in microbial limit test and antimicrobial preservative - effective. It is a modification of Soyabean Casein digest Agar prepared by completely replacing animal peptones with chemically defined peptones to avoid BSE/TSE risks associated with animal peptones.