Criopreservation of germplasm of freshwater microalgae: methodology development

• Grant number: 11/18327-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2012
• End date: December 31, 2016
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Armando Augusto Henriques Vieira
• Grantee: Letícia Piton Tessarolli
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 11/50054-4 - Biodiversity of freshwater microalgae: germplasm bank and obtaining of molecular markers of cryopreserved species, AP.BTA.TEM
• Associated scholarship(s): 14/23605-8 - Exploring functionality and stability of cryopreserved algae, BE.EP.DR

Abstract

Microalgae cultures collections are important to obtain data on organisms, including information on their physiology, genetics and phylogeny. The maintenance of cultures 'in vitro' is a widely applied technique, however, for some groups, it is noted the loss of morphological and physiological characteristics with time, which may represent detriment to economic and industrial applications, that need stable and standardized inocula, ensuring the productivity and consistency of the end products, besides the high investment of time and financial support for its maintenance. Cryopreservation is an interesting alternative, seeing that frozen cells do not perform DNA replication or thermal movement. Cryopreserved cultures are also beneficial because they require less maintenance, reducing the sources of contaminants. To achieve the objectives of cryopreservation of algal species it is necessary to apply basic theoretical knowledge about algal physiology, as well as physical and chemical pathways, modifying and applying to reach the desired practical result. In this project we will apply the widely known techniques (single step freezing, two steps freezing, vitrification, encapsulation, etc.) seeking the best cost-benefit analysis which could apply to different species, and aiming at the higher viability of cells after thawing. In addition, tests will be performed to assess the genetic stability after freezing. Beyond the study of techniques, we will analyze selected genres of algae for determination of biochemical characteristics of cultures which may act as helpers of the freezing process, including the search for natural cryoprotectants.