Isolation, Identification and Partial Characterization of a Lactobacillus casei Strain with Bile Salt Hydrolase Activity from Pulque.

The aim of this study was to isolate, from pulque, Lactobacillus spp. capable of survival in simulated gastrointestinal stress conditions. Nine Gram-positive rods were isolated; however, only one strain (J57) shared identity with Lactobacillus and was registered as Lactobacillus casei J57 (GenBank accession: JN182264). The other strains were identified as Bacillus spp. The most significant observation during the test of tolerance to simulated gastrointestinal conditions (acidity, gastric juice and bile salts) was that L. casei J57 showed a rapid decrease (p ≤ 0.05) in the viable population at 0 h. Bile salts were the stress condition that most affected its survival, from which deoxycholic acid and the mix of bile salts (oxgall) were the most toxic. L. casei J57 showed bile salt hydrolase activity over primary and secondary bile salts as follows: 44.91, 671.72, 45.27 and 61.57 U/mg to glycocholate, taurocholate, glycodeoxycholate and taurodeoxycholate. In contrast, the control strain (L. casei Shirota) only showed activity over tauroconjugates. These results suggest that L. casei J57 shows potential for probiotic applications.

Desarrollo de la produccion de inmunoglobulinas humanas especificas. I.Titulacion de la antitoxina tetanica en el proceso de obtencion de la inmunoglobulina humana normal. / Development of the production of specific human immunoglobulins. I. Titration of tetanus antitoxin during the process for obtention of human normal immunoglobulin

Este es un estudio preliminar en el desarrollo de inmunoglobulinas especificas. En este primer trabajo se determino el titulo de antitoxina tetanica por el metodo de Ipsen en varias etapas del proceso de produccion de inmunoglobulina humana normal inespecifica por las tecnicas 6 y 9 de Cohn a partir de plasma. El estudio se efectuo en tres lotes de produccion (A, B y C). Los niveles de antitoxina en unidades internacionales de antitoxina por mililitro (UIA/ml) de cada lote, desde la materia prima hasta el producto terminado, fueron: lote A: 0.069, 0.102, 3.251 y 5.848; B; 0.140, 0.177 y 12.53; lote C:0.182 0.204, 0.331 y 3.31. Tambien se estudiaron las variaciones de volumen del producto, la concentracion de proteinas y la pureza electroforetica en cada etapa. El fraccionamiente por el metodo 6 y 9 de Cohn aumento entre 18 y 89.5 veces la potencia del producto. Estos aumentos estan de acuerdo con los requerimientos minimos de la Organizacion Mundial de la Salud que fijan un aumento minino de 10 veces