Technological and functional studies of candidate´s microorganisms for probiotic products to prevent urognital infections inwomen

ESTEBAN VERA PINGITORE; MARIA SILVINA JUAREZ TOMAS; FERNANDO SESMA; MARIA ELENA FÁTIMA NADER

Sevilla. España

Simposio; Biomicroworld II; 2007

BioMicroworld Formatex

Template for abstracts submitted to BioMicroWorld2007 E. Vera Pingitore1, M. S. Juárez Tomás1, and M. E. Nader-Macías*,1 1CERELA (Centro de Referencia para Lactobacilos), Chacabuco 145, C.P. 4000, Tucumán, Argentina The infections in the female urogenital tract constitute a serious social problem and of public health, because their high prevalence (around 1 billion of persons per year in the world) and the high health-care costs involved (Reid and Bruce, 2006). These infections cause high morbi-mortality rates in women and children new born, mainly in countries where the AIDS (acquired immunodeficiency syndrome) is a prevalent disease (Reid et al., 2005). The use of probiotic to prevent urogenital infections can be an effective alternative to the antibiotic therapy. Probiotic microorganisms, such as lactobacilli, can be able to restore the balance of urogenital microflora.  In order to select probiotic microorganisms to be included in vaginal probiotic products, in previous works human vaginal Lactobacillus strains were isolated and identified. These microorganisms were characterized in terms of potentially probiotic properties and growth performances. The main objective of our research group is the design of a probiotic pharmaceutical product containing different Lactobacillus strains combined with salivaricin, a bacteriocin produced by Lactobacillus salivarius CRL 1328. For the pharmaceutical industry must be considered a commercial point of view, a method for large-scale production of concentrated cultures and bacteriocin in a form suitable for product applications and long stability, is highly desirable. A properly lyophilized formulation can maintain adequate physical and chemical stability of bacteria and protein during shipping and long-term storage, even at ambient temperatures. The aims of this work were to study the effects of different protective agents on: a) the expression of beneficial characteristics (auto-aggregation capability; production of lactic acid, hydrogen peroxide, and bacteriocin) of six freeze-dried vaginal lactobacilli, during two years of storage; b) stability of salivaricin during liophilization and storage at different temperatures, in presence of several lyoprotectors. For the first objective, Lactobacillus cells were freeze-dried in the following protectors: 12% (w/v) sucrose, 12% lactose, 6% reconstituted skim milk (RSM), and 6% RSM added with 12% sucrose or 12% lactose, and stored at 7°C. At different storage times, lyophilized cultures were rehydrated and grown in LAPTg broth during 24 h at 37°C before testing each probiotic property. For the recovery of salivaricin activity after freeze-drying, the following substances were examined: 5% sucrose, 4% sodium glutamate, 4% mannitol + 1% sucrose, 5% RSM, 5% sucrose + 0.5% PEG, 0.4% Tween 80 , 2% ascorbic acid. To know the protective efficience during subsequent storage in dried state of bacteriocin, samples were kept at 25ºC, 4ºC and ?20ºC for eight months. In all the samples the proteins concentration, inhibitory activity and weight were determined. In the present research, the six vaginal lactobacilli evaluated conserved their capabilities of antimicrobial substances production or auto-aggregation, after the freeze-drying process and during the storage for 2 years. In the case of bacteriocin, lactic acid or H2O2 producers, the variation of levels of inhibitory substances depended on the Lactobacillus strains, protective media and storage time. However, the extent of auto-aggregation of L. johnsonii CRL 1294 was high in all the conditions assayed and storage times. RSM no fué bueno en general. Los liofilizados pierden la mayor parte de su act en el primer mes y luego se mantienen relativamente estables Keywords keyword; keyword