Abstract

LACZESKI, Margarita E; NOVOSAK, Marina G  and  VERGARA, Marta I. Five Years´ Experience in Conservation of Streptococcus agalactiae: Comparison of Two Alternative Methodologies. Rev. cienc. tecnol. [online]. 2016, n.25, pp.11-14. ISSN 1851-7587.

Streptococcus agalactiae (GBS) is responsible for severe neonatal disease and other pathologies. Currently, there is a need to conserve it to carry on studies involving the search for genes of virulence and antimicrobial resistance, epidemiological studies, biotechnological developments and shipments to referral centers. The aim of this study was to compare two methods of conservation of Streptococcus agalactiae: Trypticase Soy Agar (ATS-S) to 7‰ at room temperature and darkness and skim milk at 20% at -80 .C (LD-80). One hundred and fifty strains were evaluated at three, twelve to sixty months. After shelf viability, purity, antigenic and genetic stability were verified. Recovery rates were: 100%, 80% and 15.33% for ATS-S and 100%, 100% and 98.66% for LD-80 for each period studied. Significant differences (p <0.05) were found between the two methods after the twelfth month. We conclude that LD-80 is highly effective to conserve GBS strains with recovery rates nearly a 100%.

Keywords : Streptococcus agalactiae; Preservation media; Trypticase Soy Agar; Skim milk.

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