Determination of Rennin and Bovine Pepsins in Commercial Rennets and Abomasal Juices

Abstract

A DEAE cellulose column chromatographic method is described to separate and to titrate rennin and bovine pepsin II from a mixture. Microgranular DEAE cellulose was equilibrated in .02 ~ piperazine buffer pH 5.3 and was placed on a 1 X 8 cm column. The enzyme solution was poured on the column, as such, or, if necessary, after dialysis against the same buffer. Elution of enzymes was by a linear gradient of NaCI (100 ml of .15 ~,~ NaC1 in the t~rst chamber and 100 ml of .5 M NaC1 in the second chamber). The flow was about 80 rnl per hour. Rennin was eluted in the first fraction and pepsin II in the second fraction. This method was used to determine the enzymatic composition of several commercial rennet preparations and abomasal juices collected from fistulated calves. 1641