Microalgae cryopreservation using algal exopolysaccharide as a cryoprotectant

• Grant number: 23/04395-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2023
• End date: May 31, 2024
• Field of knowledge: Biological Sciences - Botany - Applied Botany
• Principal Investigator: Inessa Lacativa Bagatini
• Grantee: Ana Luiza Bortolozzo
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Microalgae have a wide range of applications, but are still little explored considering theirgreat diversity. Culture collections are fundamental to maintain the diversity and for providing isolated organisms and substrates for biotechnological studies and commercialapplications. Metabolically active cultures and cryopreservation are the most commonlyused maintenance methods in culture collections, and, in particular, cryopreservation has a numberof advantages, such as reducing contamination, reducing the costs of long-term maintenance, in addition, it preserves the morphological, physiological, biochemical andgenetic microalgae properties. However, the cryoprotective agents (CPA) commonly used affect the viability of the organisms, as they have a certain toxicity. Alternatively, natural CPAs, aspolysaccharides produced by bacteria, have been tested in microalgae to increase thisviability. In this work, we intend to test extracellular polysaccharides (EPSs) from microalgae from the Culture Collection of Freshwater Microalgae from Federal University of São Carlos (CCMA-UFSCar), as CPA in different concentrations (10%, 15% and 20%), to optimize the cell viability after cryopreservation, when compared to the control, 5% dimethylsulfoxide(DMSO). We aim to obtain a new, less toxic CPA for the cryopreservation of populations sensitive to DMSO and other commonly used cryoprotectants, helping to maintain a cryopreserved bank and to conserve biodiversity and the biotechnologicalpotential of microalgae.