Process for the preparation of Limulina lysate

Claim 1

In a process for the preparation of Limulina lysate comprising extracting the blood of horseshoe crabs (Limulina) into an isotonic buffer solution containing an agent which inhibits the agglutination of amebocyte, separating the amebocyte from said solution, breaking the amebocyte, and recovering Limulina lysate, the improvement comprising: (A) the addition of methyl derivatives of xanthine, or the acid addition or alkali salts thereof, having the formula ##EQU2## in which R 1 , R 2 , and R 3 each represent a hydrogen atom or a methyl group, at least one of R 1 , R 2 , and R 3 being a methyl group, as the agglutination-inhibiting agent of the amebocyte, the agglutination-inhibiting agent being present at a concentration of 0.5 to 2 mM in the mixture of the isotonic buffer solution and the blood; with an optional step of (B) further extracting the amebocyte content with 20 to 50 ml, per the amount of amebocyte obtained from 100 ml of the initially extracted blood, of an extraction solvent having a pH of 6.0 to 8.0 and containing at least one alkaline earth metal ion and, optionally, an alkali metal ion, with the provisos that the alkaline earth metal ions are present at a concentration of from 2 to 60 mM and the alkali metal ions are present at a concentration of from 10 to 150 mM, and a further optional step of (C) freeze-drying the so-obtained Limulina lysate containing extraction solution.