FURTHER STUDIES ON A BOVINE PLASMA MEDIUM THAT CAN BE HEAT STERILIZED FOR LACTOBACILLI Nuevos Estudios Sobre un Medio de Cultivo de Plasma de Bovino que puede

Preparation and efficiency of a bovine plasma medium (BPM), based on liquid or powder bovine blood plasma that can be heat sterilized, is described. Protein, amino acids, and pH of the medium were analyzed, The efficiency of the BPM was compared against a commercial medium (MRS) using L. plan-tarum, L. casei. L. bulgaricus and L. acidophilus. Individual ef-fect of minerals and yeast extract were also tested. Results shown that BPM either from liquid or powder bovine plasma can be prepared by heat sterilization, remaining clear and with-out any turbidity if the pH is previously adjusted to 11. Final pH, protein and amino acid contents were similar when the BPM was prepared by either liquid or powder bovine plasma. When the efficiency of the new medium was compared against com-mercial MRS, no differences in the growth of the different Lac-tobacilli were observed. Mineral supplementation, was more ef-ficient than yeast extract for Lactobacilli growth in BPM. Even without minerals and yeast extract supplementation, an impor-tant growth of Lactobacilli was observed when liquid or powder bovine plasma was used as a source of protein. It is concluded that new low cost, practical medium has been developed for the propagation of Lactobacilli